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• Suspended Laptop Cannot Wake Up - Ubuntu

  - by Zack

  I've got an ASUS G73JH, and whenever I suspend it or hibernate it, it will not wake up. The screen stays backlight but is black. The fan remains running, however the HDD does not, not disk activity is noticeable (audibly (It's not a SSD)). I can't: Awaken it with the keyboard Awaken it with the mouse Soft power-off by pressing the power button Change virtual screens by pressing Ctrl-Alt-# Restart X by pressing Ctrl-Alt-Backspace I have to hold down the power button and shut it down that way, and this seems a little unreasonable. Is there a place I could look for more detail as to what's causing this? Is there a known quick-fix to this issue? Nothing is logged as happening when the system is in "suspend" mode. Here's what happened immediately before and after the suspend "happened," note the time gap: May 4 17:46:13 tofu NetworkManager: <info> (eth0): carrier now OFF (device state 1) May 4 17:48:57 tofu kernel: imklog 4.2.0, log source = /proc/kmsg started. This one's kinda long, here's what happened immediately before the suspend, I'm not sure if it'll help but if you can find a use for it: May 4 17:46:10 tofu anacron[3353]: Anacron 2.3 started on 2010-05-04 May 4 17:46:10 tofu anacron[3353]: Normal exit (0 jobs run) May 4 17:46:10 tofu kernel: [ 2241.775927] CPU0 attaching NULL sched-domain. May 4 17:46:10 tofu kernel: [ 2241.775958] CPU1 attaching NULL sched-domain. May 4 17:46:10 tofu kernel: [ 2241.775987] CPU2 attaching NULL sched-domain. May 4 17:46:10 tofu kernel: [ 2241.776138] CPU3 attaching NULL sched-domain. May 4 17:46:10 tofu kernel: [ 2241.776168] CPU4 attaching NULL sched-domain. May 4 17:46:10 tofu kernel: [ 2241.776197] CPU5 attaching NULL sched-domain. May 4 17:46:10 tofu kernel: [ 2241.776200] CPU6 attaching NULL sched-domain. May 4 17:46:10 tofu kernel: [ 2241.776229] CPU7 attaching NULL sched-domain. May 4 17:46:10 tofu kernel: [ 2241.919611] CPU0 attaching sched-domain: May 4 17:46:10 tofu kernel: [ 2241.919668] domain 0: span 0,4 level SIBLING May 4 17:46:10 tofu kernel: [ 2241.919699] groups: 0 (cpu_power = 589) 4 (cpu_power = 589) May 4 17:46:10 tofu kernel: [ 2241.919733] domain 1: span 0-7 level MC May 4 17:46:10 tofu kernel: [ 2241.919762] groups: 0,4 (cpu_power = 1178) 1,5 (cpu_power = 1178) 2,6 (cpu_power = 1178) 3,7 (cpu_power = 1178) May 4 17:46:10 tofu kernel: [ 2241.919850] CPU1 attaching sched-domain: May 4 17:46:10 tofu kernel: [ 2241.919852] domain 0: span 1,5 level SIBLING May 4 17:46:10 tofu kernel: [ 2241.919881] groups: 1 (cpu_power = 589) 5 (cpu_power = 589) May 4 17:46:10 tofu kernel: [ 2241.919912] domain 1: span 0-7 level MC May 4 17:46:10 tofu kernel: [ 2241.919915] groups: 1,5 (cpu_power = 1178) 2,6 (cpu_power = 1178) 3,7 (cpu_power = 1178) 0,4 (cpu_power = 1178) May 4 17:46:10 tofu kernel: [ 2241.920003] CPU2 attaching sched-domain: May 4 17:46:10 tofu kernel: [ 2241.920005] domain 0: span 2,6 level SIBLING May 4 17:46:10 tofu kernel: [ 2241.920033] groups: 2 (cpu_power = 589) 6 (cpu_power = 589) May 4 17:46:10 tofu kernel: [ 2241.920065] domain 1: span 0-7 level MC May 4 17:46:10 tofu kernel: [ 2241.920093] groups: 2,6 (cpu_power = 1178) 3,7 (cpu_power = 1178) 0,4 (cpu_power = 1178) 1,5 (cpu_power = 1178) May 4 17:46:10 tofu kernel: [ 2241.920155] CPU3 attaching sched-domain: May 4 17:46:10 tofu kernel: [ 2241.920157] domain 0: span 3,7 level SIBLING May 4 17:46:10 tofu kernel: [ 2241.920185] groups: 3 (cpu_power = 589) 7 (cpu_power = 589) May 4 17:46:10 tofu kernel: [ 2241.920217] domain 1: span 0-7 level MC May 4 17:46:10 tofu kernel: [ 2241.920245] groups: 3,7 (cpu_power = 1178) 0,4 (cpu_power = 1178) 1,5 (cpu_power = 1178) 2,6 (cpu_power = 1178) May 4 17:46:10 tofu kernel: [ 2241.920307] CPU4 attaching sched-domain: May 4 17:46:10 tofu kernel: [ 2241.920335] domain 0: span 0,4 level SIBLING May 4 17:46:10 tofu kernel: [ 2241.920337] groups: 4 (cpu_power = 589) 0 (cpu_power = 589) May 4 17:46:10 tofu kernel: [ 2241.920368] domain 1: span 0-7 level MC May 4 17:46:10 tofu kernel: [ 2241.920397] groups: 0,4 (cpu_power = 1178) 1,5 (cpu_power = 1178) 2,6 (cpu_power = 1178) 3,7 (cpu_power = 1178) May 4 17:46:10 tofu kernel: [ 2241.920459] CPU5 attaching sched-domain: May 4 17:46:10 tofu kernel: [ 2241.920487] domain 0: span 1,5 level SIBLING May 4 17:46:10 tofu kernel: [ 2241.920489] groups: 5 (cpu_power = 589) 1 (cpu_power = 589) May 4 17:46:10 tofu kernel: [ 2241.920520] domain 1: span 0-7 level MC May 4 17:46:10 tofu kernel: [ 2241.920549] groups: 1,5 (cpu_power = 1178) 2,6 (cpu_power = 1178) 3,7 (cpu_power = 1178) 0,4 (cpu_power = 1178) May 4 17:46:10 tofu kernel: [ 2241.920611] CPU6 attaching sched-domain: May 4 17:46:10 tofu kernel: [ 2241.920639] domain 0: span 2,6 level SIBLING May 4 17:46:10 tofu kernel: [ 2241.920641] groups: 6 (cpu_power = 589) 2 (cpu_power = 589) May 4 17:46:10 tofu kernel: [ 2241.920699] domain 1: span 0-7 level MC May 4 17:46:10 tofu kernel: [ 2241.920701] groups: 2,6 (cpu_power = 1178) 3,7 (cpu_power = 1178) 0,4 (cpu_power = 1178) 1,5 (cpu_power = 1178) May 4 17:46:10 tofu kernel: [ 2241.920762] CPU7 attaching sched-domain: May 4 17:46:10 tofu kernel: [ 2241.920791] domain 0: span 3,7 level SIBLING May 4 17:46:10 tofu kernel: [ 2241.920793] groups: 7 (cpu_power = 589) 3 (cpu_power = 589) May 4 17:46:10 tofu kernel: [ 2241.920851] domain 1: span 0-7 level MC May 4 17:46:10 tofu kernel: [ 2241.920853] groups: 3,7 (cpu_power = 1178) 0,4 (cpu_power = 1178) 1,5 (cpu_power = 1178) 2,6 (cpu_power = 1178) May 4 17:46:12 tofu NetworkManager: <info> Sleeping... May 4 17:46:12 tofu NetworkManager: <info> (wlan0): now unmanaged May 4 17:46:12 tofu NetworkManager: <info> (wlan0): device state change: 8 -> 1 (reason 37) May 4 17:46:12 tofu NetworkManager: <info> (wlan0): deactivating device (reason: 37). May 4 17:46:12 tofu NetworkManager: <info> (wlan0): canceled DHCP transaction, dhcp client pid 1984 May 4 17:46:12 tofu kernel: [ 2244.084515] wlan0: deauthenticating from 68:7f:74:23:02:ae by local choice (reason=3) May 4 17:46:12 tofu avahi-daemon[1176]: Withdrawing address record for 192.168.1.2 on wlan0. May 4 17:46:12 tofu avahi-daemon[1176]: Leaving mDNS multicast group on interface wlan0.IPv4 with address 192.168.1.2. May 4 17:46:12 tofu avahi-daemon[1176]: Interface wlan0.IPv4 no longer relevant for mDNS. May 4 17:46:12 tofu NetworkManager: <info> Policy set 'Auto eth0' (eth0) as default for routing and DNS. May 4 17:46:12 tofu NetworkManager: <info> (wlan0): cleaning up... May 4 17:46:12 tofu NetworkManager: <info> (wlan0): taking down device. May 4 17:46:12 tofu avahi-daemon[1176]: Withdrawing address record for 2002:4c6e:638a:0:1e4b:d6ff:fe78:951d on wlan0. May 4 17:46:12 tofu wpa_supplicant[1212]: CTRL-EVENT-DISCONNECTED - Disconnect event - remove keys May 4 17:46:13 tofu NetworkManager: <info> (eth0): now unmanaged May 4 17:46:13 tofu NetworkManager: <info> (eth0): device state change: 8 -> 1 (reason 37) May 4 17:46:13 tofu NetworkManager: <info> (eth0): deactivating device (reason: 37). May 4 17:46:13 tofu NetworkManager: <info> (eth0): canceled DHCP transaction, dhcp client pid 1559 May 4 17:46:13 tofu NetworkManager: <WARN> check_one_route(): (eth0) error -34 returned from rtnl_route_del(): Sucess#012 May 4 17:46:13 tofu avahi-daemon[1176]: Withdrawing address record for 192.168.1.3 on eth0. May 4 17:46:13 tofu avahi-daemon[1176]: Leaving mDNS multicast group on interface eth0.IPv4 with address 192.168.1.3. May 4 17:46:13 tofu avahi-daemon[1176]: Interface eth0.IPv4 no longer relevant for mDNS. May 4 17:46:13 tofu NetworkManager: <info> (eth0): cleaning up... May 4 17:46:13 tofu NetworkManager: <info> (eth0): taking down device. May 4 17:46:13 tofu avahi-daemon[1176]: Withdrawing address record for 2002:4c6e:638a:0:4a5b:39ff:fe0b:325d on eth0. May 4 17:46:13 tofu NetworkManager: <info> (eth0): carrier now OFF (device state 1)

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• Slow filesystem access

  - by danneh3826

  I'm trying to diagnose a slow filesystem issue on a server I look after. It's been ongoing for quite some time, and I've run out of ideas as to what I can try. Here's the thick of it. The server itself is a Dell Poweredge T310. It has 4 SAS hard drives in it, configured at RAID5, and is running Citrix XenServer 5.6. The VM is a (relatively) old Debian 5.0.6 installation. It's given 4 cores, and 4Gb's of RAM. It has 3 volumes. A 10Gb volume (ext3) for the system, 980Gb volume (xfs) for data (~94% full), and another 200Gb volume (xfs) for data (~13% full). Now here's the weird thing. Read/write access to the 980Gb volume is really slow. I might get 5Mb/s out of it if I'm lucky. At first I figured it was actually disk access in the system, or at a hypervisor level, but ruled that out entirely as other VMs on the same host are running perfectly fine (a good couple hundred Mb/s disk r/w access). So then I started to target this particular VM. I started thinking it was XFS, but to prove it I wasn't going to attempt to change the filesystem on the 980Gb drive, with years and years of billions of files on there. So I provisioned the 200Gb drive, and did the same read/write test (basically dd), and got a good couple hundred Mb/s r/w access to it. So that ruled out the VM, the hardware, and the filesystem type. There's also a lot of these in /var/log/kern.log; (sorry, this is quite long) Sep 4 10:16:59 uriel kernel: [32571790.564689] httpd: page allocation failure. order:5, mode:0x4020 Sep 4 10:16:59 uriel kernel: [32571790.564693] Pid: 7318, comm: httpd Not tainted 2.6.32-4-686-bigmem #1 Sep 4 10:16:59 uriel kernel: [32571790.564696] Call Trace: Sep 4 10:16:59 uriel kernel: [32571790.564705] [<c1092a4d>] ? __alloc_pages_nodemask+0x476/0x4e0 Sep 4 10:16:59 uriel kernel: [32571790.564711] [<c1092ac3>] ? __get_free_pages+0xc/0x17 Sep 4 10:16:59 uriel kernel: [32571790.564716] [<c10b632e>] ? __kmalloc+0x30/0x128 Sep 4 10:16:59 uriel kernel: [32571790.564722] [<c11dd774>] ? pskb_expand_head+0x4f/0x157 Sep 4 10:16:59 uriel kernel: [32571790.564727] [<c11ddbbf>] ? __pskb_pull_tail+0x41/0x1fb Sep 4 10:16:59 uriel kernel: [32571790.564732] [<c11e4882>] ? dev_queue_xmit+0xe4/0x38e Sep 4 10:16:59 uriel kernel: [32571790.564738] [<c1205902>] ? ip_finish_output+0x0/0x5c Sep 4 10:16:59 uriel kernel: [32571790.564742] [<c12058c7>] ? ip_finish_output2+0x187/0x1c2 Sep 4 10:16:59 uriel kernel: [32571790.564747] [<c1204dc8>] ? ip_local_out+0x15/0x17 Sep 4 10:16:59 uriel kernel: [32571790.564751] [<c12055a9>] ? ip_queue_xmit+0x31e/0x379 Sep 4 10:16:59 uriel kernel: [32571790.564758] [<c1279a90>] ? _spin_lock_bh+0x8/0x1e Sep 4 10:16:59 uriel kernel: [32571790.564767] [<eda15a8d>] ? __nf_ct_refresh_acct+0x66/0xa4 [nf_conntrack] Sep 4 10:16:59 uriel kernel: [32571790.564773] [<c103bf42>] ? _local_bh_enable_ip+0x16/0x6e Sep 4 10:16:59 uriel kernel: [32571790.564779] [<c1214593>] ? tcp_transmit_skb+0x595/0x5cc Sep 4 10:16:59 uriel kernel: [32571790.564785] [<c1005c4f>] ? xen_restore_fl_direct_end+0x0/0x1 Sep 4 10:16:59 uriel kernel: [32571790.564791] [<c12165ea>] ? tcp_write_xmit+0x7a3/0x874 Sep 4 10:16:59 uriel kernel: [32571790.564796] [<c121203a>] ? tcp_ack+0x1611/0x1802 Sep 4 10:16:59 uriel kernel: [32571790.564801] [<c10055ec>] ? xen_force_evtchn_callback+0xc/0x10 Sep 4 10:16:59 uriel kernel: [32571790.564806] [<c121392f>] ? tcp_established_options+0x1d/0x8b Sep 4 10:16:59 uriel kernel: [32571790.564811] [<c1213be4>] ? tcp_current_mss+0x38/0x53 Sep 4 10:16:59 uriel kernel: [32571790.564816] [<c1216701>] ? __tcp_push_pending_frames+0x1e/0x50 Sep 4 10:16:59 uriel kernel: [32571790.564821] [<c1212246>] ? tcp_data_snd_check+0x1b/0xd2 Sep 4 10:16:59 uriel kernel: [32571790.564825] [<c1212de3>] ? tcp_rcv_established+0x5d0/0x626 Sep 4 10:16:59 uriel kernel: [32571790.564831] [<c121902c>] ? tcp_v4_do_rcv+0x15f/0x2cf Sep 4 10:16:59 uriel kernel: [32571790.564835] [<c1219561>] ? tcp_v4_rcv+0x3c5/0x5c0 Sep 4 10:16:59 uriel kernel: [32571790.564841] [<c120197e>] ? ip_local_deliver_finish+0x10c/0x18c Sep 4 10:16:59 uriel kernel: [32571790.564846] [<c12015a4>] ? ip_rcv_finish+0x2c4/0x2d8 Sep 4 10:16:59 uriel kernel: [32571790.564852] [<c11e3b71>] ? netif_receive_skb+0x3bb/0x3d6 Sep 4 10:16:59 uriel kernel: [32571790.564864] [<ed823efc>] ? xennet_poll+0x9b8/0xafc [xen_netfront] Sep 4 10:16:59 uriel kernel: [32571790.564869] [<c11e40ee>] ? net_rx_action+0x96/0x194 Sep 4 10:16:59 uriel kernel: [32571790.564874] [<c103bd4c>] ? __do_softirq+0xaa/0x151 Sep 4 10:16:59 uriel kernel: [32571790.564878] [<c103be24>] ? do_softirq+0x31/0x3c Sep 4 10:16:59 uriel kernel: [32571790.564883] [<c103befa>] ? irq_exit+0x26/0x58 Sep 4 10:16:59 uriel kernel: [32571790.564890] [<c118ff9f>] ? xen_evtchn_do_upcall+0x12c/0x13e Sep 4 10:16:59 uriel kernel: [32571790.564896] [<c1008c3f>] ? xen_do_upcall+0x7/0xc Sep 4 10:16:59 uriel kernel: [32571790.564899] Mem-Info: Sep 4 10:16:59 uriel kernel: [32571790.564902] DMA per-cpu: Sep 4 10:16:59 uriel kernel: [32571790.564905] CPU 0: hi: 0, btch: 1 usd: 0 Sep 4 10:16:59 uriel kernel: [32571790.564908] CPU 1: hi: 0, btch: 1 usd: 0 Sep 4 10:16:59 uriel kernel: [32571790.564911] CPU 2: hi: 0, btch: 1 usd: 0 Sep 4 10:16:59 uriel kernel: [32571790.564914] CPU 3: hi: 0, btch: 1 usd: 0 Sep 4 10:16:59 uriel kernel: [32571790.564916] Normal per-cpu: Sep 4 10:16:59 uriel kernel: [32571790.564919] CPU 0: hi: 186, btch: 31 usd: 175 Sep 4 10:16:59 uriel kernel: [32571790.564922] CPU 1: hi: 186, btch: 31 usd: 165 Sep 4 10:16:59 uriel kernel: [32571790.564925] CPU 2: hi: 186, btch: 31 usd: 30 Sep 4 10:16:59 uriel kernel: [32571790.564928] CPU 3: hi: 186, btch: 31 usd: 140 Sep 4 10:16:59 uriel kernel: [32571790.564931] HighMem per-cpu: Sep 4 10:16:59 uriel kernel: [32571790.564933] CPU 0: hi: 186, btch: 31 usd: 159 Sep 4 10:16:59 uriel kernel: [32571790.564936] CPU 1: hi: 186, btch: 31 usd: 22 Sep 4 10:16:59 uriel kernel: [32571790.564939] CPU 2: hi: 186, btch: 31 usd: 24 Sep 4 10:16:59 uriel kernel: [32571790.564942] CPU 3: hi: 186, btch: 31 usd: 13 Sep 4 10:16:59 uriel kernel: [32571790.564947] active_anon:485974 inactive_anon:121138 isolated_anon:0 Sep 4 10:16:59 uriel kernel: [32571790.564948] active_file:75215 inactive_file:79510 isolated_file:0 Sep 4 10:16:59 uriel kernel: [32571790.564949] unevictable:0 dirty:516 writeback:15 unstable:0 Sep 4 10:16:59 uriel kernel: [32571790.564950] free:230770 slab_reclaimable:36661 slab_unreclaimable:21249 Sep 4 10:16:59 uriel kernel: [32571790.564952] mapped:20016 shmem:29450 pagetables:5600 bounce:0 Sep 4 10:16:59 uriel kernel: [32571790.564958] DMA free:2884kB min:72kB low:88kB high:108kB active_anon:0kB inactive_anon:0kB active_file:5692kB inactive_file:724kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:15872kB mlocked:0kB dirty:8kB writeback:0kB mapped:0kB shmem:0kB slab_reclaimable:5112kB slab_unreclaimable:156kB kernel_stack:56kB pagetables:0kB unstable:0kB bounce:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? no Sep 4 10:16:59 uriel kernel: [32571790.564964] lowmem_reserve[]: 0 698 4143 4143 Sep 4 10:16:59 uriel kernel: [32571790.564977] Normal free:143468kB min:3344kB low:4180kB high:5016kB active_anon:56kB inactive_anon:2068kB active_file:131812kB inactive_file:131728kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:715256kB mlocked:0kB dirty:156kB writeback:0kB mapped:308kB shmem:4kB slab_reclaimable:141532kB slab_unreclaimable:84840kB kernel_stack:1928kB pagetables:22400kB unstable:0kB bounce:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? no Sep 4 10:16:59 uriel kernel: [32571790.564983] lowmem_reserve[]: 0 0 27559 27559 Sep 4 10:16:59 uriel kernel: [32571790.564995] HighMem free:776728kB min:512kB low:4636kB high:8760kB active_anon:1943840kB inactive_anon:482484kB active_file:163356kB inactive_file:185588kB unevictable:0kB isolated(anon):0kB isolated(file):0kB present:3527556kB mlocked:0kB dirty:1900kB writeback:60kB mapped:79756kB shmem:117796kB slab_reclaimable:0kB slab_unreclaimable:0kB kernel_stack:0kB pagetables:0kB unstable:0kB bounce:0kB writeback_tmp:0kB pages_scanned:0 all_unreclaimable? no Sep 4 10:16:59 uriel kernel: [32571790.565001] lowmem_reserve[]: 0 0 0 0 Sep 4 10:16:59 uriel kernel: [32571790.565011] DMA: 385*4kB 16*8kB 3*16kB 9*32kB 6*64kB 2*128kB 1*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 2900kB Sep 4 10:16:59 uriel kernel: [32571790.565032] Normal: 21505*4kB 6508*8kB 273*16kB 24*32kB 3*64kB 0*128kB 0*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 143412kB Sep 4 10:16:59 uriel kernel: [32571790.565054] HighMem: 949*4kB 8859*8kB 7063*16kB 6186*32kB 4631*64kB 727*128kB 6*256kB 0*512kB 0*1024kB 0*2048kB 0*4096kB = 776604kB Sep 4 10:16:59 uriel kernel: [32571790.565076] 198980 total pagecache pages Sep 4 10:16:59 uriel kernel: [32571790.565079] 14850 pages in swap cache Sep 4 10:16:59 uriel kernel: [32571790.565082] Swap cache stats: add 2556273, delete 2541423, find 82961339/83153719 Sep 4 10:16:59 uriel kernel: [32571790.565085] Free swap = 250592kB Sep 4 10:16:59 uriel kernel: [32571790.565087] Total swap = 385520kB Sep 4 10:16:59 uriel kernel: [32571790.575454] 1073152 pages RAM Sep 4 10:16:59 uriel kernel: [32571790.575458] 888834 pages HighMem Sep 4 10:16:59 uriel kernel: [32571790.575461] 11344 pages reserved Sep 4 10:16:59 uriel kernel: [32571790.575463] 1090481 pages shared Sep 4 10:16:59 uriel kernel: [32571790.575465] 737188 pages non-shared Now, I've no idea what this means. There's plenty of free memory; total used free shared buffers cached Mem: 4247232 3455904 791328 0 5348 736412 -/+ buffers/cache: 2714144 1533088 Swap: 385520 131004 254516 Though now I see the swap is relatively low in size, but would that matter? I've been starting to think about fragmentation, or inode usage on that large partition, but a recent fsck on it showed is as only like 0.5% fragmented. Which leaves me with inode usage, but how much of an effect really would a large inode table or filesystem TOC have? I've love to hear people's opinions on this. It's driving me potty! df -h output; Filesystem Size Used Avail Use% Mounted on /dev/xvda1 9.5G 6.6G 2.4G 74% / tmpfs 2.1G 0 2.1G 0% /lib/init/rw udev 10M 520K 9.5M 6% /dev tmpfs 2.1G 0 2.1G 0% /dev/shm /dev/xvdb 980G 921G 59G 94% /data

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• What is auto-mounting my media volume?

  - by user285277

  Something is repeatedly mounting my "media" share, doing something with it, then quietly un-mounting it with no notifications at the user level. from the little I can gleaned from the console messages below, I thought I'd managed to stop it, if not understand it last night when I followed instructions for deleting all traces of the Google Update Daemon. I've not been using any Google apps whatsoever, so I was surprised to see that in Console. What's more surprising, and perhaps a little distressing, is that the same thing occurred this evening, when the Google Daemon is long gone. I don't have that log because I can't recall precisely what time it occurred. I'll do a search and provide it if you wish, though. In the meantime, any help with this would be extremely appreciated. I've asked over at Apple Discussions but I think it might be a little deeper than those manning the boards this weekend are comfortable with. It's certainly beyond my meager skills. With apologies in advance if this is more lines thank you need. Please note that I've transformed the Google links a little because the forum here requires more reputation points before one can post more than two links. 12/27/13 10:47:31.000 PM kernel[0]: memorystatus_thread: idle exiting pid 53629 [distnoted] 12/27/13 10:48:10.433 PM com.apple.Preview.TrustedBookmarksService[53640]: Failed to resolve bookmark data at index: 0; not stale; error: The file doesn’t exist. 12/27/13 10:48:10.434 PM com.apple.Preview.TrustedBookmarksService[53640]: Failed to resolve bookmark data at index: 1; not stale; error: The file doesn’t exist. 12/27/13 10:48:10.950 PM com.apple.SecurityServer[17]: Session 103257 created 12/27/13 10:48:34.328 PM com.apple.Preview.TrustedBookmarksService[53640]: Failed to resolve bookmark data at index: 2; not stale; error: The file doesn’t exist. 12/27/13 10:48:34.000 PM kernel[0]: AFP_VFS afpfs_mount: /Volumes/Media Archive-1, pid 53641 12/27/13 10:48:34.000 PM kernel[0]: AFP_VFS afpfs_mount : succeeded on volume 0xffffff80d6355008 /Volumes/Media Archive-1 (error = 0, retval = 0) 12/27/13 10:49:32.000 PM kernel[0]: wlEvent: en0 en0 Link DOWN virtIf = 0 12/27/13 10:49:32.000 PM kernel[0]: AirPort: Link Down on en0. Reason 8 (Disassociated because station leaving). 12/27/13 10:49:32.000 PM kernel[0]: en0::IO80211Interface::postMessage bssid changed 12/27/13 10:49:33.681 PM configd[16]: network changed: v4(en0-:10.0.1.12) DNS- Proxy- SMB 12/27/13 10:49:33.697 PM configd[16]: network changed: DNS* Proxy 12/27/13 10:49:35.475 PM KernelEventAgent[57]: tid 00000000 received event(s) VQ_NOTRESP (1) 12/27/13 10:49:35.000 PM kernel[0]: ASP_TCP Disconnect: triggering reconnect by bumping reconnTrigger from curr value 0 on so 0xffffff802176b4a0 12/27/13 10:49:35.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect started /Volumes/Media Archive-1 prevTrigger 0 currTrigger 1 12/27/13 10:49:35.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: doing reconnect on /Volumes/Media Archive-1 12/27/13 10:49:35.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: posting to KEA EINPROGRESS for /Volumes/Media Archive-1 12/27/13 10:49:35.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: Max reconnect time: 600 secs, Connect timeout: 15 secs for /Volumes/Media Archive-1 12/27/13 10:49:35.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: connect to the server /Volumes/Media Archive-1 12/27/13 10:49:35.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: connect on /Volumes/Media Archive-1 failed 65. 12/27/13 10:49:35.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: sleep for 1 seconds and then try again 12/27/13 10:49:35.479 PM KernelEventAgent[57]: tid 00000000 type 'afpfs', mounted on '/Volumes/Media Archive-1', from '//Me@Capsule._afpovertcp._tcp.local/Media%20Archive', not responding 12/27/13 10:49:35.487 PM KernelEventAgent[57]: tid 00000000 found 1 filesystem(s) with problem(s) 12/27/13 10:49:36.692 PM com.bourgeoisbits.cloak.agent[14503]: NetworkProfile: (null), (null), (null) (Connected: NO, Airport: NO, Open: NO) [trusted] 12/27/13 10:49:36.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: connect to the server /Volumes/Media Archive-1 12/27/13 10:49:36.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: connect on /Volumes/Media Archive-1 failed 65. 12/27/13 10:49:36.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: sleep for 2 seconds and then try again 12/27/13 10:49:38.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: connect to the server /Volumes/Media Archive-1 12/27/13 10:49:38.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: connect on /Volumes/Media Archive-1 failed 65. 12/27/13 10:49:38.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: sleep for 4 seconds and then try again 12/27/13 10:49:41.000 PM kernel[0]: CODE SIGNING: cs_invalid_page(0x1000): p=53662[GoogleSoftwareUp] clearing CS_VALID 12/27/13 10:49:42.102 PM GoogleSoftwareUpdateDaemon[53663]: -[KeystoneDaemon logServiceState] GoogleSoftwareUpdate daemon (1.1.0.3659) vending: com.google.Keystone.Daemon.UpdateEngine: 2 connection(s) com.google.Keystone.Daemon.Administration: 0 connection(s) 12/27/13 10:49:42.113 PM GoogleSoftwareUpdateDaemon[53663]: -[KSUpdateEngine updateProductID:] KSUpdateEngine updating product ID: "com.google.Keystone" 12/27/13 10:49:42.116 PM GoogleSoftwareUpdateDaemon[53663]: -[KSCheckAction performAction] KSCheckAction checking 1 ticket(s). 12/27/13 10:49:42.121 PM GoogleSoftwareUpdateDaemon[53663]: -[KSUpdateCheckAction performAction] KSUpdateCheckAction starting update check for ticket(s): {( <KSTicket:0x531870 productID=com.google.Keystone version=1.1.0.3659 xc=<KSPathExistenceChecker:0x5302d0 path=/Library/Google/GoogleSoftwareUpdate/GoogleSoftwareUpdate.bundle/> serverType=Omaha url=htt[PeeEs]://tools.google.com/service/update2 creationDate=2012-08-12 14:47:10 > )} Using server: <KSOmahaServer:0x534340 engine=<KSDaemonUpdateEngine:0x52e530> params={ EngineVersion = "1.1.0.3659"; ActivesInfo = { "com.google.talkplugin" = { LastRollCallPingDate = 2013-10-06 07:00:00 +0000; }; "com.google.Keystone" = { LastRollCallPingDate = 2013-10-06 07:00:00 +0000; LastActivePingDate = 2013-10-06 07:00:00 +0000; LastActiveDate = 2013-12-28 03:49:42 +0000; }; "com.google.picasa" = { LastActiveDate = 2012-08-29 10:15:42 +0000; }; }; UserInitiated = 0; IsSystem = 1; OmahaOSVersion = "10.8.5_i486"; Identity = KeystoneDaemon; AllowedSubdomains = ( ".omaha.sandbox.google.com", ".tools.google.com", ".www.google.com", ".corp.google.com" ); } > 12/27/13 10:49:42.130 PM GoogleSoftwareUpdateDaemon[53663]: -[KSUpdateCheckAction performAction] KSUpdateCheckAction running KSServerUpdateRequest: <KSOmahaServerUpdateRequest:0x1a31a90 server=<KSOmahaServer:0x534340> url="htt[PeeEs]://tools.google.com/service/update2" runningFetchers=0 tickets=1 activeTickets=1 rollCallTickets=1 body= <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <o:gupdate xmlns:o="htt[Pee]://www.google.com/update2/request" protocol="2.0" version="KeystoneDaemon-1.1.0.3659" ismachine="1"> <o:os platform="mac" version="MacOSX" sp="10.8.5_i486"></o:os> <o:app appid="com.google.Keystone" version="1.1.0.3659" lang="en-us" installage="502" brand="GGLG"> <o:ping r="82" a="82"></o:ping> <o:updatecheck></o:updatecheck> </o:app> </o:gupdate> > 12/27/13 10:49:42.291 PM GoogleSoftwareUpdateDaemon[53663]: -[KSOutOfProcessFetcher(PrivateMethods) helperDidTerminate:] The Internet connection appears to be offline. [NSURLErrorDomain:-1009] 12/27/13 10:49:42.291 PM GoogleSoftwareUpdateDaemon[53663]: -[KSServerUpdateRequest(PrivateMethods) fetcher:failedWithError:] KSServerUpdateRequest fetch failed. (productIDs: com.google.Keystone) [com.google.UpdateEngine.CoreErrorDomain:702 - 'htt[PeeEs]://tools.google.com/service/update2'] (The Internet connection appears to be offline. [NSURLErrorDomain:-1009]) 12/27/13 10:49:42.292 PM GoogleSoftwareUpdateDaemon[53663]: -[KSUpdateCheckAction(PrivateMethods) finishAction] KSUpdateCheckAction found updates: {( )} 12/27/13 10:49:42.295 PM GoogleSoftwareUpdateDaemon[53663]: -[KSPrefetchAction performAction] KSPrefetchAction no updates to prefetch. 12/27/13 10:49:42.295 PM GoogleSoftwareUpdateDaemon[53663]: -[KSMultiUpdateAction performAction] KSSilentUpdateAction had no updates to apply. 12/27/13 10:49:42.296 PM GoogleSoftwareUpdateDaemon[53663]: -[KSMultiUpdateAction performAction] KSPromptAction had no updates to apply. 12/27/13 10:49:42.299 PM GoogleSoftwareUpdateDaemon[53663]: -[KSUpdateEngine(PrivateMethods) updateFinish] KSUpdateEngine update processing complete. 12/27/13 10:49:42.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: connect to the server /Volumes/Media Archive-1 12/27/13 10:49:42.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: connect on /Volumes/Media Archive-1 failed 65. 12/27/13 10:49:42.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: sleep for 8 seconds and then try again 12/27/13 10:49:43.152 PM GoogleSoftwareUpdateDaemon[53663]: -[KSUpdateEngine updateAllProducts] KSUpdateEngine updating all installed products. 12/27/13 10:49:43.153 PM GoogleSoftwareUpdateDaemon[53663]: -[KSCheckAction performAction] KSCheckAction checking 2 ticket(s). 12/27/13 10:49:43.158 PM GoogleSoftwareUpdateDaemon[53663]: -[KSUpdateCheckAction performAction] KSUpdateCheckAction starting update check for ticket(s): {( <KSTicket:0x18367a0 productID=com.google.Keystone version=1.1.0.3659 xc=<KSPathExistenceChecker:0x1837e10 path=/Library/Google/GoogleSoftwareUpdate/GoogleSoftwareUpdate.bundle/> serverType=Omaha url=htt[PeeEs]://tools.google.com/service/update2 creationDate=2012-08-12 14:47:10 >, <KSTicket:0x1834750 productID=com.google.talkplugin version=4.7.0.15362 xc=<KSPathExistenceChecker:0x1833890 path=/Library/Application Support/Google/GoogleTalkPlugin.app> serverType=Omaha url=htt[PeeEs]://tools.google.com/service/update2 creationDate=2012-08-12 14:47:10 > )} Using server: <KSOmahaServer:0x52e930 engine=<KSDaemonUpdateEngine:0x52e530> params={ EngineVersion = "1.1.0.3659"; ActivesInfo = { "com.google.talkplugin" = { LastRollCallPingDate = 2013-10-06 07:00:00 +0000; }; "com.google.Keystone" = { LastRollCallPingDate = 2013-10-06 07:00:00 +0000; LastActivePingDate = 2013-10-06 07:00:00 +0000; LastActiveDate = 2013-12-28 03:49:42 +0000; }; "com.google.picasa" = { LastActiveDate = 2012-08-29 10:15:42 +0000; }; }; UserInitiated = 0; IsSystem = 1; OmahaOSVersion = "10.8.5_i486"; Identity = KeystoneDaemon; AllowedSubdomains = ( ".omaha.sandbox.google.com", ".tools.google.com", ".www.google.com", ".corp.google.com" ); } > 12/27/13 10:49:43.159 PM GoogleSoftwareUpdateDaemon[53663]: -[KSUpdateCheckAction performAction] KSUpdateCheckAction running KSServerUpdateRequest: <KSOmahaServerUpdateRequest:0x53a210 server=<KSOmahaServer:0x52e930> url="htt[PeeEs]://tools.google.com/service/update2" runningFetchers=0 tickets=2 activeTickets=1 rollCallTickets=2 body= <?xml version="1.0" encoding="UTF-8" standalone="yes"?> <o:gupdate xmlns:o="htt[Pee]://www.google.com/update2/request" protocol="2.0" version="KeystoneDaemon-1.1.0.3659" ismachine="1"> <o:os platform="mac" version="MacOSX" sp="10.8.5_i486"></o:os> <o:app appid="com.google.Keystone" version="1.1.0.3659" lang="en-us" installage="502" brand="GGLG"> <o:ping r="82" a="82"></o:ping> <o:updatecheck></o:updatecheck> </o:app> <o:app appid="com.google.talkplugin" version="4.7.0.15362" lang="en-us" installage="502" brand="GGLG"> <o:ping r="82"></o:ping> <o:updatecheck></o:updatecheck> </o:app> </o:gupdate> > 12/27/13 10:49:43.243 PM GoogleSoftwareUpdateDaemon[53663]: -[KSOutOfProcessFetcher(PrivateMethods) helperDidTerminate:] The Internet connection appears to be offline. [NSURLErrorDomain:-1009] 12/27/13 10:49:43.243 PM GoogleSoftwareUpdateDaemon[53663]: -[KSServerUpdateRequest(PrivateMethods) fetcher:failedWithError:] KSServerUpdateRequest fetch failed. (productIDs: com.google.Keystone, ... (2)) [com.google.UpdateEngine.CoreErrorDomain:702 - 'htt[PeeEs]://tools.google.com/service/update2'] (The Internet connection appears to be offline. [NSURLErrorDomain:-1009]) 12/27/13 10:49:43.244 PM GoogleSoftwareUpdateDaemon[53663]: -[KSUpdateCheckAction(PrivateMethods) finishAction] KSUpdateCheckAction found updates: {( )} 12/27/13 10:49:43.247 PM GoogleSoftwareUpdateDaemon[53663]: -[KSPrefetchAction performAction] KSPrefetchAction no updates to prefetch. 12/27/13 10:49:43.248 PM GoogleSoftwareUpdateDaemon[53663]: -[KSMultiUpdateAction performAction] KSSilentUpdateAction had no updates to apply. 12/27/13 10:49:43.248 PM GoogleSoftwareUpdateDaemon[53663]: -[KSMultiUpdateAction performAction] KSPromptAction had no updates to apply. 12/27/13 10:49:43.250 PM GoogleSoftwareUpdateDaemon[53663]: -[KSUpdateEngine(PrivateMethods) updateFinish] KSUpdateEngine update processing complete. 12/27/13 10:49:45.570 PM GoogleSoftwareUpdateDaemon[53663]: -[KeystoneDaemon logServiceState] GoogleSoftwareUpdate daemon (1.1.0.3659) vending: com.google.Keystone.Daemon.UpdateEngine: 1 connection(s) com.google.Keystone.Daemon.Administration: 0 connection(s) 12/27/13 10:49:50.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: connect to the server /Volumes/Media Archive-1 12/27/13 10:49:50.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: connect on /Volumes/Media Archive-1 failed 65. 12/27/13 10:49:50.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: sleep for 10 seconds and then try again 12/27/13 10:49:53.828 PM KernelEventAgent[57]: tid 00000000 unmounting 1 filesystems 12/27/13 10:49:53.000 PM kernel[0]: AFP_VFS afpfs_unmount: /Volumes/Media Archive-1, flags 524288, pid 57 12/27/13 10:49:54.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: get the reconnect token 12/27/13 10:49:54.000 PM kernel[0]: AFP_VFS afpfs_DoReconnect: GetReconnectToken failed 32 /Volumes/Media Archive-1 12/27/13 10:49:54.000 PM kernel[0]: AFP_VFS afpfs_unmount : afpfs_DoReconnect sent signal for unmount to proceed 12/27/13 10:50:12.104 PM GoogleSoftwareUpdateDaemon[53663]: -[KeystoneDaemon main] GoogleSoftwareUpdateDaemon inactive, shutdown. 12/27/13 10:50:29.396 PM Dock[93157]: no information back from LS about running process

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• Alternate way to create a clone of a UNIX System

  - by Spirit

  THE STORY: (If you don't like to read much, down below is the question :) ) Where I work we have two HP RP2470 servers same hardware same number of hard drives same everything :). One of them is a production server and runs HP-UX 11.00. The poor ba***rd hasn't been turned off for years and now I have to make a clone of it on the other server - just in case, for redundancy. The problem is simple (or not simple) as I have to make the the other server exactly the same. However the old version of OS (UX 11.00 is a history now) and the old software running on it, have made my task almost impossible. On the production server there is also a cloning/recover utility Ignite-UX. I tried many times to create a recovery tape with it. Then when I load the tape on the backup server, it succeeds with the loading of the tape (no errors no warnings) but on the next restart it fails to load the OS :S and drops into HP`s ISL prompt. --- THE QUESTION: Is there an alternate way to create a clone of the Unix System? The environment is: 1. 2x HP RP2470 Servers (non-Intel), same hardware, same number od HDDs (two each of them) same everything. 2. OS running: HP-UX 11.00 The production server has to be cloned without downtime - sadly :( as I hope that they will reconsider on this one For example (like on Windows platforms), if you try to copy an entire HDD with Windows inside on another HDD, and then put that HDD on another PC it will still work, as long as the hardware is the same. Can I do something like that with a Unix system? Can I somehow COPY the contents of the entire HDD, put those on another HDD, and then just load the HDD into the other server? (If you haven't read the story the servers are exactly the same) Will it work? Can it be done with ordinary commands like cp or dump or something like that? Does any one have a similar experience? --- UPDATE: 26.01.2012 NOTE: The update is related to "The Story". If you haven't read that part then you can skip this update. This is just a short update on the recover logs from the Ignite Tape.. someone with more exp. might notice something.. ... --- READING CONTENTS OF THE IGNITE TAPE --- --- OUTPUT OMITED --- ... ... x ./configure3, 413696 bytes, 808 tape blocks x ./monitor_bpr, 20480 bytes, 40 tape blocks * Download_mini-system: Complete * Loading_software: Begin * Installing boot area on disk. * Enabling swap areas. * Backing up LVM configuration for "vg00". * Processing the archive source (Recovery Archive). * Wed Jan 25 15:27:32 EST 2012: Starting archive load of the source (Recovery Archive). * Positioning the tape (/dev/rmt/0mn). * Archive extraction from tape is beginning. Please wait. * Wed Jan 25 15:39:52 EST 2012: Completed archive load of the source (Recovery Archive). * Executing user specified script: "/opt/ignite/data/scripts/os_arch_post_l". * Running in recovery mode (os_arch_post_l). * Running the ioinit command ("/sbin/ioinit -c") * Creating device files via the insf command. insf: Installing special files for sdisk instance 0 address 0/0/1/1.15.0 insf: Installing special files for sdisk instance 1 address 0/0/2/0.1.0 insf: Installing special files for sdisk instance 2 address 0/0/2/1.15.0 insf: Installing special files for stape instance 0 address 0/0/1/0.3.0 insf: Installing special files for btlan instance 0 address 0/0/0/0 insf: Installing special files for btlan instance 1 address 0/2/0/0 insf: Installing special files for pseudo driver dlpi insf: Installing special files for pseudo driver kepd insf: Installing special files for pseudo driver framebuf insf: Installing special files for pseudo driver sad * Running "/opt/upgrade/bin/tlinstall -v" and correcting transition link permissions. * Constructing the bootconf file. * Setting primary boot path to "0/0/1/1.15.0". * Executing: "/var/adm/sw/products/PHSS_20146/pfiles/iux_postload". * Executing: "/var/adm/sw/products/PHSS_25982/pfiles/iux_postload". NOTE: tlinstall is searching filesystem - please be patient NOTE: Successfully completed * Loading_software: Complete * Build_Kernel: Begin NOTE: Since the /stand/vmunix kernel is already in place, the kernel will not be re-built. Note that no mod_kernel directives will be processed. * Build_Kernel: Complete * Boot_From_Client_Disk: Begin * Rebooting machine as expected. NOTE: Rebooting system. sync'ing disks (0 buffers to flush): 0 buffers not flushed 0 buffers still dirty Closing open logical volumes... Done Console reset done. Boot device reset done. ********** VIRTUAL FRONT PANEL ********** System Boot detected ***************************************** LEDs: RUN ATTENTION FAULT REMOTE POWER FLASH OFF OFF ON ON LED State: Running non-OS code. (i.e. Boot or Diagnostics) ... ... ... --- SERVER IS PERFORMING POST SEQUENCE HERE --- --- OUTPUT OMITED --- ... ... ... ***************************************** ************ EARLY BOOT VFP ************* End of early boot detected ***************************************** Firmware Version 43.50 Duplex Console IO Dependent Code (IODC) revision 1 ------------------------------------------------------------------------------ (c) Copyright 1995-2002, Hewlett-Packard Company, All rights reserved ------------------------------------------------------------------------------ Processor Speed State CoProcessor State Cache Size Number State Inst Data --------- -------- --------------------- ----------------- ------------ 0 650 MHz Active Functional 750 KB 1.5 MB 1 650 MHz Idle Functional 750 KB 1.5 MB Central Bus Speed (in MHz) : 120 Available Memory : 2097152 KB Good Memory Required : 16140 KB Primary boot path: 0/0/1/1.15 Alternate boot path: 0/0/2/1.15 Console path: 0/0/4/1.643 Keyboard path: 0/0/4/0.0 Processor is starting autoboot process. To discontinue, press any key within 10 seconds. 10 seconds expired. Proceeding... Trying Primary Boot Path ------------------------ Booting... Boot IO Dependent Code (IODC) revision 1 HARD Booted. ISL Revision A.00.38 OCT 26, 1994 ISL booting hpux ISL>

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• After connecting wlan0 to bridge interface (and then removing it), can't connect to AP

  - by gmonk

  I'm on a laptop running Debian Jessie with kernel 3.13-1-amd64; lspci shows that my wireless NIC + driver is 04:00.0 Network controller: Intel Corporation Wireless 3160 (rev 83) Subsystem: Intel Corporation Dual Band Wireless-AC 3160 Kernel driver in use: iwlwifi This has been working without any problems, until I tried creating a bridge for lxc containers to use. I did the same thing as this person here: How-to set up a network bridge on a laptop for LXC use? -- and ended up having the same problem as this poster did, so I decided to "undo" my actions. This hasn't been successful. Actions taken so far: To configure the bridge: #> ip link add type veth #> iw dev wlan0 set 4addr on #> ifconfig veth0 up #> brctl addbr br0 #> brctl addif br0 wlan0 #> brctl addif br0 veth0 #> ifconfig br0 192.168.0.4/24 #> ifconfig wlan0 0.0.0.0 To "deconfigure": #> brctl delif br0 wlan0 #> brctl delif br0 veth0 #> iw dev wlan0 set 4addr off #> ifconfig veth0 down #> ifconfig wlan0 down #> ifconfig br0 down #> brctl delbr br0 Now, dmesg and /var/log/syslog show repeated attempts at connecting to the AP that was working before, which fail after authentication: May 27 09:16:01 myhostname kernel: [11350.757172] wlan0: authenticate with 00:18:f8:54:a3:d6 May 27 09:16:01 myhostname kernel: [11350.759036] wlan0: send auth to 00:18:f8:54:a3:d6 (try 1/3) May 27 09:16:01 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: scanning -> authenticating May 27 09:16:01 myhostname wpa_supplicant[8946]: wlan0: Trying to associate with 00:18:f8:54:a3:d6 (SSID='myaccesspoint' freq=2437 MHz) May 27 09:16:01 myhostname kernel: [11350.762615] wlan0: authenticated May 27 09:16:01 myhostname kernel: [11350.762753] iwlwifi 0000:04:00.0 wlan0: disabling HT as WMM/QoS is not supported by the AP May 27 09:16:01 myhostname kernel: [11350.762755] iwlwifi 0000:04:00.0 wlan0: disabling VHT as WMM/QoS is not supported by the AP May 27 09:16:01 myhostname kernel: [11350.765080] wlan0: associate with 00:18:f8:54:a3:d6 (try 1/3) May 27 09:16:01 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: authenticating -> associating May 27 09:16:01 myhostname kernel: [11350.767474] wlan0: RX AssocResp from 00:18:f8:54:a3:d6 (capab=0x411 status=12 aid=0) May 27 09:16:01 myhostname kernel: [11350.767476] wlan0: 00:18:f8:54:a3:d6 denied association (code=12) May 27 09:16:01 myhostname wpa_supplicant[8946]: wlan0: CTRL-EVENT-ASSOC-REJECT bssid=00:18:f8:54:a3:d6 status_code=12 May 27 09:16:01 myhostname kernel: [11350.788475] wlan0: deauthenticating from 00:18:f8:54:a3:d6 by local choice (reason=3) May 27 09:16:01 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: associating -> disconnected May 27 09:16:01 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: disconnected -> scanning May 27 09:16:02 myhostname dhclient: DHCPDISCOVER on wlan0 to 255.255.255.255 port 67 interval 14 May 27 09:16:04 myhostname wpa_supplicant[8946]: wlan0: SME: Trying to authenticate with 00:18:f8:54:a3:d6 (SSID='myaccesspoint' freq=2437 MHz) May 27 09:16:04 myhostname kernel: [11354.559579] wlan0: authenticate with 00:18:f8:54:a3:d6 May 27 09:16:04 myhostname kernel: [11354.561458] wlan0: send auth to 00:18:f8:54:a3:d6 (try 1/3) May 27 09:16:04 myhostname wpa_supplicant[8946]: wlan0: Trying to associate with 00:18:f8:54:a3:d6 (SSID='myaccesspoint' freq=2437 MHz) May 27 09:16:04 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: scanning -> associating May 27 09:16:04 myhostname kernel: [11354.563445] wlan0: authenticated May 27 09:16:04 myhostname kernel: [11354.563631] iwlwifi 0000:04:00.0 wlan0: disabling HT as WMM/QoS is not supported by the AP May 27 09:16:04 myhostname kernel: [11354.563633] iwlwifi 0000:04:00.0 wlan0: disabling VHT as WMM/QoS is not supported by the AP May 27 09:16:04 myhostname kernel: [11354.565727] wlan0: associate with 00:18:f8:54:a3:d6 (try 1/3) May 27 09:16:04 myhostname wpa_supplicant[8946]: wlan0: Associated with 00:18:f8:54:a3:d6 May 27 09:16:04 myhostname kernel: [11354.568091] wlan0: RX AssocResp from 00:18:f8:54:a3:d6 (capab=0x411 status=0 aid=9) May 27 09:16:04 myhostname kernel: [11354.569030] wlan0: associated May 27 09:16:04 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: associating -> associated May 27 09:16:05 myhostname kernel: [11354.978204] wlan0: deauthenticated from 00:18:f8:54:a3:d6 (Reason: 15) May 27 09:16:05 myhostname wpa_supplicant[8946]: wlan0: CTRL-EVENT-DISCONNECTED bssid=00:18:f8:54:a3:d6 reason=15 May 27 09:16:05 myhostname kernel: [11354.992729] cfg80211: Calling CRDA to update world regulatory domain May 27 09:16:05 myhostname kernel: [11354.995004] cfg80211: World regulatory domain updated: May 27 09:16:05 myhostname kernel: [11354.995005] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp) May 27 09:16:05 myhostname kernel: [11354.995006] cfg80211: (2402000 KHz - 2472000 KHz @ 40000 KHz), (N/A, 2000 mBm) May 27 09:16:05 myhostname kernel: [11354.995007] cfg80211: (2457000 KHz - 2482000 KHz @ 40000 KHz), (N/A, 2000 mBm) May 27 09:16:05 myhostname kernel: [11354.995007] cfg80211: (2474000 KHz - 2494000 KHz @ 20000 KHz), (N/A, 2000 mBm) May 27 09:16:05 myhostname kernel: [11354.995008] cfg80211: (5170000 KHz - 5250000 KHz @ 80000 KHz), (N/A, 2000 mBm) May 27 09:16:05 myhostname kernel: [11354.995009] cfg80211: (5735000 KHz - 5835000 KHz @ 80000 KHz), (N/A, 2000 mBm) May 27 09:16:05 myhostname kernel: [11354.995010] cfg80211: (57240000 KHz - 63720000 KHz @ 2160000 KHz), (N/A, 0 mBm) May 27 09:16:05 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: associated -> disconnected May 27 09:16:05 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: disconnected -> scanning May 27 09:16:09 myhostname wpa_supplicant[8946]: wlan0: SME: Trying to authenticate with 00:18:f8:54:a3:d6 (SSID='myaccesspoint' freq=2437 MHz) May 27 09:16:09 myhostname kernel: [11358.763968] wlan0: authenticate with 00:18:f8:54:a3:d6 May 27 09:16:09 myhostname kernel: [11358.765796] wlan0: send auth to 00:18:f8:54:a3:d6 (try 1/3) May 27 09:16:09 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: scanning -> authenticating May 27 09:16:09 myhostname wpa_supplicant[8946]: wlan0: Trying to associate with 00:18:f8:54:a3:d6 (SSID='myaccesspoint' freq=2437 MHz) May 27 09:16:09 myhostname kernel: [11358.769957] wlan0: authenticated May 27 09:16:09 myhostname kernel: [11358.770102] iwlwifi 0000:04:00.0 wlan0: disabling HT as WMM/QoS is not supported by the AP May 27 09:16:09 myhostname kernel: [11358.770104] iwlwifi 0000:04:00.0 wlan0: disabling VHT as WMM/QoS is not supported by the AP May 27 09:16:09 myhostname kernel: [11358.770846] wlan0: associate with 00:18:f8:54:a3:d6 (try 1/3) May 27 09:16:09 myhostname kernel: [11358.773358] wlan0: RX AssocResp from 00:18:f8:54:a3:d6 (capab=0x411 status=12 aid=0) May 27 09:16:09 myhostname kernel: [11358.773361] wlan0: 00:18:f8:54:a3:d6 denied association (code=12) May 27 09:16:09 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: authenticating -> associating May 27 09:16:09 myhostname wpa_supplicant[8946]: wlan0: CTRL-EVENT-ASSOC-REJECT bssid=00:18:f8:54:a3:d6 status_code=12 May 27 09:16:09 myhostname kernel: [11358.802187] wlan0: deauthenticating from 00:18:f8:54:a3:d6 by local choice (reason=3) May 27 09:16:09 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: associating -> disconnected May 27 09:16:09 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: disconnected -> scanning May 27 09:16:12 myhostname wpa_supplicant[8946]: wlan0: SME: Trying to authenticate with 00:18:f8:54:a3:d6 (SSID='myaccesspoint' freq=2437 MHz) May 27 09:16:12 myhostname kernel: [11362.573442] wlan0: authenticate with 00:18:f8:54:a3:d6 May 27 09:16:12 myhostname kernel: [11362.575270] wlan0: send auth to 00:18:f8:54:a3:d6 (try 1/3) May 27 09:16:12 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: scanning -> authenticating May 27 09:16:12 myhostname wpa_supplicant[8946]: wlan0: Trying to associate with 00:18:f8:54:a3:d6 (SSID='myaccesspoint' freq=2437 MHz) May 27 09:16:12 myhostname kernel: [11362.580334] wlan0: authenticated May 27 09:16:12 myhostname kernel: [11362.580503] iwlwifi 0000:04:00.0 wlan0: disabling HT as WMM/QoS is not supported by the AP May 27 09:16:12 myhostname kernel: [11362.580516] iwlwifi 0000:04:00.0 wlan0: disabling VHT as WMM/QoS is not supported by the AP May 27 09:16:12 myhostname kernel: [11362.583508] wlan0: associate with 00:18:f8:54:a3:d6 (try 1/3) May 27 09:16:12 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: authenticating -> associating May 27 09:16:12 myhostname wpa_supplicant[8946]: wlan0: Associated with 00:18:f8:54:a3:d6 May 27 09:16:12 myhostname kernel: [11362.585908] wlan0: RX AssocResp from 00:18:f8:54:a3:d6 (capab=0x411 status=0 aid=9) May 27 09:16:12 myhostname kernel: [11362.586781] wlan0: associated May 27 09:16:12 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: associating -> associated May 27 09:16:13 myhostname kernel: [11362.947693] wlan0: deauthenticated from 00:18:f8:54:a3:d6 (Reason: 15) May 27 09:16:13 myhostname wpa_supplicant[8946]: wlan0: CTRL-EVENT-DISCONNECTED bssid=00:18:f8:54:a3:d6 reason=15 May 27 09:16:13 myhostname kernel: [11362.973461] cfg80211: Calling CRDA to update world regulatory domain May 27 09:16:13 myhostname kernel: [11362.975673] cfg80211: World regulatory domain updated: May 27 09:16:13 myhostname kernel: [11362.975675] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp) May 27 09:16:13 myhostname kernel: [11362.975676] cfg80211: (2402000 KHz - 2472000 KHz @ 40000 KHz), (N/A, 2000 mBm) May 27 09:16:13 myhostname kernel: [11362.975677] cfg80211: (2457000 KHz - 2482000 KHz @ 40000 KHz), (N/A, 2000 mBm) May 27 09:16:13 myhostname kernel: [11362.975678] cfg80211: (2474000 KHz - 2494000 KHz @ 20000 KHz), (N/A, 2000 mBm) May 27 09:16:13 myhostname kernel: [11362.975678] cfg80211: (5170000 KHz - 5250000 KHz @ 80000 KHz), (N/A, 2000 mBm) May 27 09:16:13 myhostname kernel: [11362.975679] cfg80211: (5735000 KHz - 5835000 KHz @ 80000 KHz), (N/A, 2000 mBm) May 27 09:16:13 myhostname kernel: [11362.975679] cfg80211: (57240000 KHz - 63720000 KHz @ 2160000 KHz), (N/A, 0 mBm) May 27 09:16:13 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: associated -> disconnected May 27 09:16:13 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: disconnected -> scanning May 27 09:16:14 myhostname NetworkManager[13992]: <warn> Activation (wlan0/wireless): association took too long. May 27 09:16:14 myhostname NetworkManager[13992]: <info> (wlan0): device state change: config -> failed (reason 'no-secrets') [50 120 7] May 27 09:16:14 myhostname NetworkManager[13992]: <info> Marking connection 'Auto myaccesspoint' invalid. May 27 09:16:14 myhostname NetworkManager[13992]: <warn> Activation (wlan0) failed for connection 'Auto myaccesspoint' May 27 09:16:14 myhostname NetworkManager[13992]: <info> (wlan0): device state change: failed -> disconnected (reason 'none') [120 30 0] May 27 09:16:14 myhostname NetworkManager[13992]: <info> (wlan0): deactivating device (reason 'none') [0] May 27 09:16:14 myhostname NetworkManager[13992]: <info> (wlan0): supplicant interface state: scanning -> disconnected The things that jump out at me are "deauthenticating ... by local choice( reason=3)" and the lines that contain "(reason=15)". I've tried various fixes: iwconfig wlan0 power off killing wpa_supplicant connecting with iwconfig + dhclient instead of gnome's network -manager explicitly configuring wlan0 in /etc/network/interfaces creating a /etc/wpa_supplicant.conf file ...but nothing seems to work. I'm not sure what I did wrong, or what step I've skipped in trying to get wlan0 back as a non-bridged device -- I removed it from the bridge and then deleted the bridge itself. Any ideas?

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• How do I prevent TCP connection freezes over an OpenVPN network?

  - by Jason R

  New details added at the end of this question; it's possible that I'm zeroing in on the cause. I have a UDP OpenVPN-based VPN set up in tap mode (I need tap because I need the VPN to pass multicast packets, which doesn't seem to be possible with tun networks) with a handful of clients across the Internet. I've been experiencing frequent TCP connection freezes over the VPN. That is, I will establish a TCP connection (e.g. an SSH connection, but other protocols have similar issues), and at some point during the session, it seems that traffic will cease being transmitted over that TCP session. This seems to be related to points at which large data transfers occur, such as if I execute an ls command in an SSH session, or if I cat a long log file. Some Google searches turn up a number of answers like this previous one on Server Fault, indicating that the likely culprit is an MTU issue: that during periods of high traffic, the VPN is trying to send packets that get dropped somewhere in the pipes between the VPN endpoints. The above-linked answer suggests using the following OpenVPN configuration settings to mitigate the problem: fragment 1400 mssfix This should limit the MTU used on the VPN to 1400 bytes and fix the TCP maximum segment size to prevent the generation of any packets larger than that. This seems to mitigate the problem a bit, but I still frequently see the freezes. I've tried a number of sizes as arguments to the fragment directive: 1200, 1000, 576, all with similar results. I can't think of any strange network topology between the two ends that could trigger such a problem: the VPN server is running on a pfSense machine connected directly to the Internet, and my client is also connected directly to the Internet at another location. One other strange piece of the puzzle: if I run the tracepath utility, then that seems to band-aid the problem. A sample run looks like: [~]$ tracepath -n 192.168.100.91 1: 192.168.100.90 0.039ms pmtu 1500 1: 192.168.100.91 40.823ms reached 1: 192.168.100.91 19.846ms reached Resume: pmtu 1500 hops 1 back 64 The above run is between two clients on the VPN: I initiated the trace from 192.168.100.90 to the destination of 192.168.100.91. Both clients were configured with fragment 1200; mssfix; in an attempt to limit the MTU used on the link. The above results would seem to suggest that tracepath was able to detect a path MTU of 1500 bytes between the two clients. I would assume that it would be somewhat smaller due to the fragmentation settings specified in the OpenVPN configuration. I found that result somewhat strange. Even stranger, however: if I have a TCP connection in the stalled state (e.g. an SSH session with a directory listing that froze in the middle), then executing the tracepath command shown above causes the connection to start up again! I can't figure out any reasonable explanation for why this would be the case, but I feel like this might be pointing toward a solution to ultimately eradicate the problem. Does anyone have any recommendations for other things to try? Edit: I've come back and looked at this a bit further, and have found only more confounding information: I set the OpenVPN connection to fragment at 1400 bytes, as shown above. Then, I connected to the VPN from across the Internet and used Wireshark to look at the UDP packets that were sent to the VPN server while the stall occurred. None were greater than the specified 1400 byte count, so the fragmentation seems to be functioning properly. To verify that even a 1400-byte MTU would be sufficient, I pinged the VPN server using the following (Linux) command: ping <host> -s 1450 -M do This (I believe) sends a 1450-byte packet with fragmentation disabled (I at least verified that it didn't work if I set it to an obviously-too-large value like 1600 bytes). These seem to work just fine; I get replies back from the host with no issue. So, maybe this isn't an MTU issue at all. I'm just confused as to what else it might be! Edit 2: The rabbit hole just keeps getting deeper: I've now isolated the problem a bit more. It seems to be related to the exact OS that the VPN client uses. I have successfully duplicated the problem on at least three Ubuntu machines (versions 12.04 through 13.04). I can reliably duplicate an SSH connection freeze within a minute or so by just cat-ing a large log file. However, if I do the same test using a CentOS 6 machine as a client, then I don't see the problem! I've tested using the exact same OpenVPN client version as I was using on the Ubuntu machines. I can cat log files for hours without seeing the connection freeze. This seems to provide some insight as to the ultimate cause, but I'm just not sure what that insight is. I have examined the traffic over the VPN using Wireshark. I'm not a TCP expert, so I'm not sure what to make of the gory details, but the gist is that at some point, a UDP packet gets dropped due to the limited bandwidth of the Internet link, causing TCP retransmissions inside the VPN tunnel. On the CentOS client, these retransmissions occur properly and things move on happily. At some point with the Ubuntu clients, though, the remote end starts retransmitting the same TCP segment over and over (with the transmit delay increasing between each retransmission). The client sends what looks like a valid TCP ACK to each retransmission, but the remote end still continues to transmit the same TCP segment periodically. This extends ad infinitum and the connection stalls. My question here would be: Does anyone have any recommendations for how to troubleshoot and/or determine the root cause of the TCP issue? It's as if the remote end isn't accepting the ACK messages sent by the VPN client. One common difference between the CentOS node and the various Ubuntu releases is that Ubuntu has a much more recent Linux kernel version (from 3.2 in Ubuntu 12.04 to 3.8 in 13.04). A pointer to some new kernel bug maybe? I'm assuming that if that were so, then I wouldn't be the only one experiencing the problem; I don't think this seems like a particularly exotic setup.

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• Network throughput issue (ARP-related)

  - by Joel Coel

  The small college where I work is having some very strange network issues. I'm looking for any advice or ideas here. We were fine over the summer, but the trouble began few days after students returned to campus in force for the fall term. Symptoms The main symptom is that internet access will work, but it's very slow... often to the point of timeouts. As an example, a typical result from Speedtest.net will return .4Mbps download, but allow 3 to 8 Mbps upload speed. Lesser symptoms may include severely limited performance transferring data to and from our file server, or even in some cases the inability to log in to the computer (cannot reach the domain controller). The issue crosses multiple vlans, and has effected devices on nearly every vlan we operate. The issue does not impact all machines on the network. An unaffected machine will typically see at least 11Mbps download from speedtest.net, and perhaps much more depending on larger campus traffic patterns at the time. There is one variation on the larger issue. We have one vlan where users were unable to log into nearly all of the machines at all. IT staff would log in using a local administrator account (or in some cases cached credentials), and from there a release/renew or pinging the gateway would allow the machine to work... for a while. Complicating this issue is that this vlan covers our computer labs, which use software called Deep Freeze to completely reset the hard drives after a reboot. It could just the same issue manifesting differently because of stale data on machines that have not permanently altered low-level info for weeks. We were able to solve this, however, by creating a new vlan and moving the labs over to the new vlan wholesale. Instigations Eventually we noticed that the effected machines all had recent dhcp leases. We can predict when a machine will become "slow" by watching when a dhcp lease comes up for renewal. We played with setting the lease time very short for a test vlan, but all that did was remove our ability to predict when the machine would become slow. Machines with static IPs have pretty much always worked normally. Manually releasing/renewing an address will never cause a machine to become slow. In fact, in some cases this process has fixed a machine in that state. Most of the time, though, it doesn't help. We also noticed that mobile machines like laptops are likely to become slow when they cross to new vlans. Wireless on campus is divided up into "zones", where each zone maps to a small set of buildings. Moving to a new building can place you in a zone, thereby causing you to get a new address. A machine resuming from sleep mode is also very likely to be slow. Mitigations Sometimes, but not always, clearing the arp cache on an effected machine will allow it to work normally again. As already mentioned, releasing/renewing a local machine's IP address can fix that machine, but it's not guaranteed. Pinging the default gateway can also sometimes help with a slow machine. What seems to help most to mitigate the issue is clearing the arp cache on our core layer-3 switch. This switch is used for our dhcp system as the default gateway on all vlans, and it handles inter-vlan routing. The model is a 3Com 4900SX. To try to mitigate the issue, we have the cache timeout set on the switch all the way down to the lowest possible time, but it hasn't helped. I also put together a script that runs every few minutes to automatically connect to the switch and reset the cache. Unfortunately, this does not always work, and can even cause some machines to end up in the slow state for a short time (though these seem to correct themselves after a few minutes). We currently have a scheduled job that runs every 10 minutes to force the core switch to clear it's ARP cache, but this is far from perfect or desirable. Reproduction We now have a test machine that we can force into the slow state at will. It is connected to a switch with ports set up for each of our vlans. We make the machine slow by connecting to different vlans, and after a new connection or two it will be slow. It's also worth noting in this section that this has happened before at the start of prior terms, but in the past the problem has gone away on it's own after a few days. It solved itself before we had a chance to do much diagnostic work... hence why we've allowed it to drag so long into the term this time 'round; the expectation was this would be a short-lived situation. Other Factors It's worth mentioning that we have had about half a dozen switches just outright fail over the last year. These are mainly 2003/2004-era 3Coms (mostly 4200's) that were all put in at about the same time. They should still be covered under warranty, buy HP has made getting service somewhat difficult. Mostly in power supplies that have failed, but in a couple cases we have used a power supply from a switch with a failed mainboard to bring a switch with a failed power supply back to life. We do have UPS devices on all but three of four switches now, but that was not the case when I started two and a half years ago. Severe budget constraints (we were on the Dept. of Ed's financially challenged institutions list a couple years back) have forced me to look to the likes of Netgear and TrendNet for replacements, but so far these low-end models seem to be holding their own. It's also worth mentioning that the big change on our network this summer was migrating from a single cross-campus wireless SSID to the zoned approach mentioned earlier. I don't think this is the source of the issue, as like I've said: we've seen this before. However, it's possible this is exacerbating the issue, and may be much of the reason it's been so hard to isolate. Diagnosis At first it seemed clear to us, given the timing and persistent nature of the problem, that the source of the issue was an infected (or malicious) student machine doing ARP cache poisoning. However, repeated attempts to isolate the source have failed. Those attempts include numerous wireshark packet traces, and even taking entire buildings offline for brief periods. We have not been able even to find a smoking gun bad ARP entry. My current best guess is an overloaded or failing core switch, but I'm not sure on how to test for this, and the cost of replacing it blindly is steep. Again, any ideas appreciated.

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• MySQL hangs if connection comes from outside the LAN

  - by Subito

  I have a MySQL Server operating just fine if I access him from his local LAN (192.168.100.0/24). If I try to access hin from another LAN (192.168.113.0/24 in this case) it hangs for a really long time before delivering the result. SHOW PROCESSLIST; shows this process in Sleep, State empty. If I strace -p this process I get the following Output (23512 is the PID of the corresponding mysqld process): Process 23512 attached - interrupt to quit restart_syscall(<... resuming interrupted call ...>) = 1 fcntl(10, F_GETFL) = 0x2 (flags O_RDWR) fcntl(10, F_SETFL, O_RDWR|O_NONBLOCK) = 0 accept(10, {sa_family=AF_INET, sin_port=htons(51696), sin_addr=inet_addr("192.168.113.4")}, [16]) = 33 fcntl(10, F_SETFL, O_RDWR) = 0 rt_sigaction(SIGCHLD, {SIG_DFL, [CHLD], SA_RESTORER|SA_RESTART, 0x7f9ce7ca34f0}, {SIG_DFL, [CHLD], SA_RESTORER|SA_RESTART, 0x7f9ce7ca34f0}, ) = 0 getpeername(33, {sa_family=AF_INET, sin_port=htons(51696), sin_addr=inet_addr("192.168.113.4")}, [16]) = 0 getsockname(33, {sa_family=AF_INET, sin_port=htons(3306), sin_addr=inet_addr("192.168.100.190")}, [16]) = 0 open("/etc/hosts.allow", O_RDONLY) = 64 fstat(64, {st_mode=S_IFREG|0644, st_size=580, ...}) = 0 mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f9ce9839000 read(64, "# /etc/hosts.allow: list of host"..., 4096) = 580 read(64, "", 4096) = 0 close(64) = 0 munmap(0x7f9ce9839000, 4096) = 0 open("/etc/hosts.deny", O_RDONLY) = 64 fstat(64, {st_mode=S_IFREG|0644, st_size=880, ...}) = 0 mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f9ce9839000 read(64, "# /etc/hosts.deny: list of hosts"..., 4096) = 880 read(64, "", 4096) = 0 close(64) = 0 munmap(0x7f9ce9839000, 4096) = 0 getsockname(33, {sa_family=AF_INET, sin_port=htons(3306), sin_addr=inet_addr("192.168.100.190")}, [16]) = 0 fcntl(33, F_SETFL, O_RDONLY) = 0 fcntl(33, F_GETFL) = 0x2 (flags O_RDWR) setsockopt(33, SOL_SOCKET, SO_RCVTIMEO, "\36\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", 16) = 0 setsockopt(33, SOL_SOCKET, SO_SNDTIMEO, "<\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", 16) = 0 fcntl(33, F_SETFL, O_RDWR|O_NONBLOCK) = 0 setsockopt(33, SOL_IP, IP_TOS, [8], 4) = 0 setsockopt(33, SOL_TCP, TCP_NODELAY, [1], 4) = 0 futex(0x7f9cea5c9564, FUTEX_WAKE_OP_PRIVATE, 1, 1, 0x7f9cea5c9560, {FUTEX_OP_SET, 0, FUTEX_OP_CMP_GT, 1}) = 1 futex(0x7f9cea5c6fe0, FUTEX_WAKE_PRIVATE, 1) = 1 poll([{fd=10, events=POLLIN}, {fd=12, events=POLLIN}], 2, -1) = 1 ([{fd=10, revents=POLLIN}]) fcntl(10, F_GETFL) = 0x2 (flags O_RDWR) fcntl(10, F_SETFL, O_RDWR|O_NONBLOCK) = 0 accept(10, {sa_family=AF_INET, sin_port=htons(51697), sin_addr=inet_addr("192.168.113.4")}, [16]) = 31 fcntl(10, F_SETFL, O_RDWR) = 0 rt_sigaction(SIGCHLD, {SIG_DFL, [CHLD], SA_RESTORER|SA_RESTART, 0x7f9ce7ca34f0}, {SIG_DFL, [CHLD], SA_RESTORER|SA_RESTART, 0x7f9ce7ca34f0}, ) = 0 getpeername(31, {sa_family=AF_INET, sin_port=htons(51697), sin_addr=inet_addr("192.168.113.4")}, [16]) = 0 getsockname(31, {sa_family=AF_INET, sin_port=htons(3306), sin_addr=inet_addr("192.168.100.190")}, [16]) = 0 open("/etc/hosts.allow", O_RDONLY) = 33 fstat(33, {st_mode=S_IFREG|0644, st_size=580, ...}) = 0 mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f9ce9839000 read(33, "# /etc/hosts.allow: list of host"..., 4096) = 580 read(33, "", 4096) = 0 close(33) = 0 munmap(0x7f9ce9839000, 4096) = 0 open("/etc/hosts.deny", O_RDONLY) = 33 fstat(33, {st_mode=S_IFREG|0644, st_size=880, ...}) = 0 mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f9ce9839000 read(33, "# /etc/hosts.deny: list of hosts"..., 4096) = 880 read(33, "", 4096) = 0 close(33) = 0 munmap(0x7f9ce9839000, 4096) = 0 getsockname(31, {sa_family=AF_INET, sin_port=htons(3306), sin_addr=inet_addr("192.168.100.190")}, [16]) = 0 fcntl(31, F_SETFL, O_RDONLY) = 0 fcntl(31, F_GETFL) = 0x2 (flags O_RDWR) setsockopt(31, SOL_SOCKET, SO_RCVTIMEO, "\36\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", 16) = 0 setsockopt(31, SOL_SOCKET, SO_SNDTIMEO, "<\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0", 16) = 0 fcntl(31, F_SETFL, O_RDWR|O_NONBLOCK) = 0 setsockopt(31, SOL_IP, IP_TOS, [8], 4) = 0 setsockopt(31, SOL_TCP, TCP_NODELAY, [1], 4) = 0 futex(0x7f9cea5c9564, FUTEX_WAKE_OP_PRIVATE, 1, 1, 0x7f9cea5c9560, {FUTEX_OP_SET, 0, FUTEX_OP_CMP_GT, 1}) = 1 futex(0x7f9cea5c6fe0, FUTEX_WAKE_PRIVATE, 1) = 1 poll([{fd=10, events=POLLIN}, {fd=12, events=POLLIN}], 2, -1^C <unfinished ...> Process 23512 detached This output repeats itself until the answer gets send. It could take up to 15 Minutes until the request gets served. In the local LAN its a matter of Milliseconds. Why is this and how can I debug this further? [Edit] tcpdump shows a ton of this: 14:49:44.103107 IP cassandra-test.mysql > 192.168.X.6.64626: Flags [S.], seq 1434117703, ack 1793610733, win 14600, options [mss 1460,nop,nop,sackOK,nop,wscale 7], length 0 14:49:44.135187 IP 192.168.X.6.64625 > cassandra-test.mysql: Flags [P.], seq 106:145, ack 182, win 4345, length 39 14:49:44.135293 IP cassandra-test.mysql > 192.168.X.6.64625: Flags [P.], seq 182:293, ack 145, win 115, length 111 14:49:44.167025 IP 192.168.X.6.64624 > cassandra-test.mysql: Flags [.], ack 444, win 4280, length 0 14:49:44.168933 IP 192.168.X.6.64626 > cassandra-test.mysql: Flags [.], ack 1, win 4390, length 0 14:49:44.169088 IP cassandra-test.mysql > 192.168.X.6.64626: Flags [P.], seq 1:89, ack 1, win 115, length 88 14:49:44.169672 IP 192.168.X.6.64625 > cassandra-test.mysql: Flags [P.], seq 145:171, ack 293, win 4317, length 26 14:49:44.169726 IP cassandra-test.mysql > 192.168.X.6.64625: Flags [P.], seq 293:419, ack 171, win 115, length 126 14:49:44.275111 IP 192.168.X.6.64626 > cassandra-test.mysql: Flags [P.], seq 1:74, ack 89, win 4368, length 73 14:49:44.275131 IP cassandra-test.mysql > 192.168.X.6.64626: Flags [.], ack 74, win 115, length 0 14:49:44.275149 IP 192.168.X.6.64625 > cassandra-test.mysql: Flags [P.], seq 171:180, ack 419, win 4286, length 9 14:49:44.275189 IP cassandra-test.mysql > 192.168.X.6.64626: Flags [P.], seq 89:100, ack 74, win 115, length 11 14:49:44.275264 IP 192.168.X.6.64625 > cassandra-test.mysql: Flags [P.], seq 180:185, ack 419, win 4286, length 5 14:49:44.275281 IP cassandra-test.mysql > 192.168.X.6.64625: Flags [.], ack 185, win 115, length 0 14:49:44.275295 IP cassandra-test.mysql > 192.168.X.6.64625: Flags [F.], seq 419, ack 185, win 115, length 0 14:49:44.275650 IP 192.168.X.6.64625 > cassandra-test.mysql: Flags [F.], seq 185, ack 419, win 4286, length 0 14:49:44.275660 IP cassandra-test.mysql > 192.168.X.6.64625: Flags [.], ack 186, win 115, length 0 14:49:44.275910 IP 192.168.X.6.64627 > cassandra-test.mysql: Flags [S], seq 2336421549, win 8192, options [mss 1351,nop,wscale 2,nop,nop,sackOK], length 0 14:49:44.275921 IP cassandra-test.mysql > 192.168.X.6.64627: Flags [S.], seq 3289359778, ack 2336421550, win 14600, options [mss 1460,nop,nop,sackOK,nop,wscale 7], length 0

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• A free standing ASP.NET Pager Web Control

  - by Rick Strahl

  Paging in ASP.NET has been relatively easy with stock controls supporting basic paging functionality. However, recently I built an MVC application and one of the things I ran into was that I HAD TO build manual paging support into a few of my pages. Dealing with list controls and rendering markup is easy enough, but doing paging is a little more involved. I ended up with a small but flexible component that can be dropped anywhere. As it turns out the task of creating a semi-generic Pager control for MVC was fairly easily. Now I’m back to working in Web Forms and thought to myself that the way I created the pager in MVC actually would also work in ASP.NET – in fact quite a bit easier since the whole thing can be conveniently wrapped up into an easily reusable control. A standalone pager would provider easier reuse in various pages and a more consistent pager display regardless of what kind of 'control’ the pager is associated with. Why a Pager Control? At first blush it might sound silly to create a new pager control – after all Web Forms has pretty decent paging support, doesn’t it? Well, sort of. Yes the GridView control has automatic paging built in and the ListView control has the related DataPager control. The built in ASP.NET paging has several issues though: Postback and JavaScript requirements If you look at paging links in ASP.NET they are always postback links with javascript:__doPostback() calls that go back to the server. While that works fine and actually has some benefit like the fact that paging saves changes to the page and post them back, it’s not very SEO friendly. Basically if you use javascript based navigation nosearch engine will follow the paging links which effectively cuts off list content on the first page. The DataPager control does support GET based links via the QueryStringParameter property, but the control is effectively tied to the ListView control (which is the only control that implements IPageableItemContainer). DataSource Controls required for Efficient Data Paging Retrieval The only way you can get paging to work efficiently where only the few records you display on the page are queried for and retrieved from the database you have to use a DataSource control - only the Linq and Entity DataSource controls  support this natively. While you can retrieve this data yourself manually, there’s no way to just assign the page number and render the pager based on this custom subset. Other than that default paging requires a full resultset for ASP.NET to filter the data and display only a subset which can be very resource intensive and wasteful if you’re dealing with largish resultsets (although I’m a firm believer in returning actually usable sets :-}). If you use your own business layer that doesn’t fit an ObjectDataSource you’re SOL. That’s a real shame too because with LINQ based querying it’s real easy to retrieve a subset of data that is just the data you want to display but the native Pager functionality doesn’t support just setting properties to display just the subset AFAIK. DataPager is not Free Standing The DataPager control is the closest thing to a decent Pager implementation that ASP.NET has, but alas it’s not a free standing component – it works off a related control and the only one that it effectively supports from the stock ASP.NET controls is the ListView control. This means you can’t use the same data pager formatting for a grid and a list view or vice versa and you’re always tied to the control. Paging Events In order to handle paging you have to deal with paging events. The events fire at specific time instances in the page pipeline and because of this you often have to handle data binding in a way to work around the paging events or else end up double binding your data sources based on paging. Yuk. Styling The GridView pager is a royal pain to beat into submission for styled rendering. The DataPager control has many more options and template layout and it renders somewhat cleaner, but it too is not exactly easy to get a decent display for. Not a Generic Solution The problem with the ASP.NET controls too is that it’s not generic. GridView, DataGrid use their own internal paging, ListView can use a DataPager and if you want to manually create data layout – well you’re on your own. IOW, depending on what you use you likely have very different looking Paging experiences. So, I figured I’ve struggled with this once too many and finally sat down and built a Pager control. The Pager Control My goal was to create a totally free standing control that has no dependencies on other controls and certainly no requirements for using DataSource controls. The idea is that you should be able to use this pager control without any sort of data requirements at all – you should just be able to set properties and be able to display a pager. The Pager control I ended up with has the following features: Completely free standing Pager control – no control or data dependencies Complete manual control – Pager can render without any data dependency Easy to use: Only need to set PageSize, ActivePage and TotalItems Supports optional filtering of IQueryable for efficient queries and Pager rendering Supports optional full set filtering of IEnumerable<T> and DataTable Page links are plain HTTP GET href Links Control automatically picks up Page links on the URL and assigns them (automatic page detection no page index changing events to hookup) Full CSS Styling support On the downside there’s no templating support for the control so the layout of the pager is relatively fixed. All elements however are stylable and there are options to control the text, and layout options such as whether to display first and last pages and the previous/next buttons and so on. To give you an idea what the pager looks like, here are two differently styled examples (all via CSS):   The markup for these two pagers looks like this: <ww:Pager runat="server" id="ItemPager" PageSize="5" PageLinkCssClass="gridpagerbutton" SelectedPageCssClass="gridpagerbutton-selected" PagesTextCssClass="gridpagertext" CssClass="gridpager" RenderContainerDiv="true" ContainerDivCssClass="gridpagercontainer" MaxPagesToDisplay="6" PagesText="Item Pages:" NextText="next" PreviousText="previous" /> <ww:Pager runat="server" id="ItemPager2" PageSize="5" RenderContainerDiv="true" MaxPagesToDisplay="6" /> The latter example uses default style settings so it there’s not much to set. The first example on the other hand explicitly assigns custom styles and overrides a few of the formatting options. Styling The styling is based on a number of CSS classes of which the the main pager, pagerbutton and pagerbutton-selected classes are the important ones. Other styles like pagerbutton-next/prev/first/last are based on the pagerbutton style. The default styling shown for the red outlined pager looks like this: .pagercontainer { margin: 20px 0; background: whitesmoke; padding: 5px; } .pager { float: right; font-size: 10pt; text-align: left; } .pagerbutton,.pagerbutton-selected,.pagertext { display: block; float: left; text-align: center; border: solid 2px maroon; min-width: 18px; margin-left: 3px; text-decoration: none; padding: 4px; } .pagerbutton-selected { font-size: 130%; font-weight: bold; color: maroon; border-width: 0px; background: khaki; } .pagerbutton-first { margin-right: 12px; } .pagerbutton-last,.pagerbutton-prev { margin-left: 12px; } .pagertext { border: none; margin-left: 30px; font-weight: bold; } .pagerbutton a { text-decoration: none; } .pagerbutton:hover { background-color: maroon; color: cornsilk; } .pagerbutton-prev { background-image: url(images/prev.png); background-position: 2px center; background-repeat: no-repeat; width: 35px; padding-left: 20px; } .pagerbutton-next { background-image: url(images/next.png); background-position: 40px center; background-repeat: no-repeat; width: 35px; padding-right: 20px; margin-right: 0px; } Yup that’s a lot of styling settings although not all of them are required. The key ones are pagerbutton, pager and pager selection. The others (which are implicitly created by the control based on the pagerbutton style) are for custom markup of the ‘special’ buttons. In my apps I tend to have two kinds of pages: Those that are associated with typical ‘grid’ displays that display purely tabular data and those that have a more looser list like layout. The two pagers shown above represent these two views and the pager and gridpager styles in my standard style sheet reflect these two styles. Configuring the Pager with Code Finally lets look at what it takes to hook up the pager. As mentioned in the highlights the Pager control is completely independent of other controls so if you just want to display a pager on its own it’s as simple as dropping the control and assigning the PageSize, ActivePage and either TotalPages or TotalItems. So for this markup: <ww:Pager runat="server" id="ItemPagerManual" PageSize="5" MaxPagesToDisplay="6" /> I can use code as simple as: ItemPagerManual.PageSize = 3; ItemPagerManual.ActivePage = 4;ItemPagerManual.TotalItems = 20; Note that ActivePage is not required - it will automatically use any Page=x query string value and assign it, although you can override it as I did above. TotalItems can be any value that you retrieve from a result set or manually assign as I did above. A more realistic scenario based on a LINQ to SQL IQueryable result is even easier. In this example, I have a UserControl that contains a ListView control that renders IQueryable data. I use a User Control here because there are different views the user can choose from with each view being a different user control. This incidentally also highlights one of the nice features of the pager: Because the pager is independent of the control I can put the pager on the host page instead of into each of the user controls. IOW, there’s only one Pager control, but there are potentially many user controls/listviews that hold the actual display data. The following code demonstrates how to use the Pager with an IQueryable that loads only the records it displays: protected voidPage_Load(objectsender, EventArgs e) {     Category = Request.Params["Category"] ?? string.Empty;     IQueryable<wws_Item> ItemList = ItemRepository.GetItemsByCategory(Category);     // Update the page and filter the list down     ItemList = ItemPager.FilterIQueryable<wws_Item>(ItemList); // Render user control with a list view Control ulItemList = LoadControl("~/usercontrols/" + App.Configuration.ItemListType + ".ascx"); ((IInventoryItemListControl)ulItemList).InventoryItemList = ItemList; phItemList.Controls.Add(ulItemList); // placeholder } The code uses a business object to retrieve Items by category as an IQueryable which means that the result is only an expression tree that hasn’t execute SQL yet and can be further filtered. I then pass this IQueryable to the FilterIQueryable() helper method of the control which does two main things: Filters the IQueryable to retrieve only the data displayed on the active page Sets the Totaltems property and calculates TotalPages on the Pager and that’s it! When the Pager renders it uses those values, plus the PageSize and ActivePage properties to render the Pager. In addition to IQueryable there are also filter methods for IEnumerable<T> and DataTable, but these versions just filter the data by removing rows/items from the entire already retrieved data. Output Generated and Paging Links The output generated creates pager links as plain href links. Here’s what the output looks like: <div id="ItemPager" class="pagercontainer"> <div class="pager"> <span class="pagertext">Pages: </span><a href="http://localhost/WestWindWebStore/itemlist.aspx?Page=1" class="pagerbutton" />1</a> <a href="http://localhost/WestWindWebStore/itemlist.aspx?Page=2" class="pagerbutton" />2</a> <a href="http://localhost/WestWindWebStore/itemlist.aspx?Page=3" class="pagerbutton" />3</a> <span class="pagerbutton-selected">4</span> <a href="http://localhost/WestWindWebStore/itemlist.aspx?Page=5" class="pagerbutton" />5</a> <a href="http://localhost/WestWindWebStore/itemlist.aspx?Page=6" class="pagerbutton" />6</a> <a href="http://localhost/WestWindWebStore/itemlist.aspx?Page=20" class="pagerbutton pagerbutton-last" />20</a>&nbsp;<a href="http://localhost/WestWindWebStore/itemlist.aspx?Page=3" class="pagerbutton pagerbutton-prev" />Prev</a>&nbsp;<a href="http://localhost/WestWindWebStore/itemlist.aspx?Page=5" class="pagerbutton pagerbutton-next" />Next</a></div> <br clear="all" /> </div> </div> The links point back to the current page and simply append a Page= page link into the page. When the page gets reloaded with the new page number the pager automatically detects the page number and automatically assigns the ActivePage property which results in the appropriate page to be displayed. The code shown in the previous section is all that’s needed to handle paging. Note that HTTP GET based paging is different than the Postback paging ASP.NET uses by default. Postback paging preserves modified page content when clicking on pager buttons, but this control will simply load a new page – no page preservation at this time. The advantage of not using Postback paging is that the URLs generated are plain HTML links that a search engine can follow where __doPostback() links are not. Pager with a Grid The pager also works in combination with grid controls so it’s easy to bypass the grid control’s paging features if desired. In the following example I use a gridView control and binds it to a DataTable result which is also filterable by the Pager control. The very basic plain vanilla ASP.NET grid markup looks like this: <div style="width: 600px; margin: 0 auto;padding: 20px; "> <asp:DataGrid runat="server" AutoGenerateColumns="True" ID="gdItems" CssClass="blackborder" style="width: 600px;"> <AlternatingItemStyle CssClass="gridalternate" /> <HeaderStyle CssClass="gridheader" /> </asp:DataGrid> <ww:Pager runat="server" ID="Pager" CssClass="gridpager" ContainerDivCssClass="gridpagercontainer" PageLinkCssClass="gridpagerbutton" SelectedPageCssClass="gridpagerbutton-selected" PageSize="8" RenderContainerDiv="true" MaxPagesToDisplay="6" /> </div> and looks like this when rendered: using custom set of CSS styles. The code behind for this code is also very simple: protected void Page_Load(object sender, EventArgs e) { string category = Request.Params["category"] ?? ""; busItem itemRep = WebStoreFactory.GetItem(); var items = itemRep.GetItemsByCategory(category) .Select(itm => new {Sku = itm.Sku, Description = itm.Description}); // run query into a DataTable for demonstration DataTable dt = itemRep.Converter.ToDataTable(items,"TItems"); // Remove all items not on the current page dt = Pager.FilterDataTable(dt,0); // bind and display gdItems.DataSource = dt; gdItems.DataBind(); } A little contrived I suppose since the list could already be bound from the list of elements, but this is to demonstrate that you can also bind against a DataTable if your business layer returns those. Unfortunately there’s no way to filter a DataReader as it’s a one way forward only reader and the reader is required by the DataSource to perform the bindings.  However, you can still use a DataReader as long as your business logic filters the data prior to rendering and provides a total item count (most likely as a second query). Control Creation The control itself is a pretty brute force ASP.NET control. Nothing clever about this other than some basic rendering logic and some simple calculations and update routines to determine which buttons need to be shown. You can take a look at the full code from the West Wind Web Toolkit’s Repository (note there are a few dependencies). To give you an idea how the control works here is the Render() method: /// <summary> /// overridden to handle custom pager rendering for runtime and design time /// </summary> /// <param name="writer"></param> protected override void Render(HtmlTextWriter writer) { base.Render(writer); if (TotalPages == 0 && TotalItems > 0) TotalPages = CalculateTotalPagesFromTotalItems(); if (DesignMode) TotalPages = 10; // don't render pager if there's only one page if (TotalPages < 2) return; if (RenderContainerDiv) { if (!string.IsNullOrEmpty(ContainerDivCssClass)) writer.AddAttribute("class", ContainerDivCssClass); writer.RenderBeginTag("div"); } // main pager wrapper writer.WriteBeginTag("div"); writer.AddAttribute("id", this.ClientID); if (!string.IsNullOrEmpty(CssClass)) writer.WriteAttribute("class", this.CssClass); writer.Write(HtmlTextWriter.TagRightChar + "\r\n"); // Pages Text writer.WriteBeginTag("span"); if (!string.IsNullOrEmpty(PagesTextCssClass)) writer.WriteAttribute("class", PagesTextCssClass); writer.Write(HtmlTextWriter.TagRightChar); writer.Write(this.PagesText); writer.WriteEndTag("span"); // if the base url is empty use the current URL FixupBaseUrl(); // set _startPage and _endPage ConfigurePagesToRender(); // write out first page link if (ShowFirstAndLastPageLinks && _startPage != 1) { writer.WriteBeginTag("a"); string pageUrl = StringUtils.SetUrlEncodedKey(BaseUrl, QueryStringPageField, (1).ToString()); writer.WriteAttribute("href", pageUrl); if (!string.IsNullOrEmpty(PageLinkCssClass)) writer.WriteAttribute("class", PageLinkCssClass + " " + PageLinkCssClass + "-first"); writer.Write(HtmlTextWriter.SelfClosingTagEnd); writer.Write("1"); writer.WriteEndTag("a"); writer.Write("&nbsp;"); } // write out all the page links for (int i = _startPage; i < _endPage + 1; i++) { if (i == ActivePage) { writer.WriteBeginTag("span"); if (!string.IsNullOrEmpty(SelectedPageCssClass)) writer.WriteAttribute("class", SelectedPageCssClass); writer.Write(HtmlTextWriter.TagRightChar); writer.Write(i.ToString()); writer.WriteEndTag("span"); } else { writer.WriteBeginTag("a"); string pageUrl = StringUtils.SetUrlEncodedKey(BaseUrl, QueryStringPageField, i.ToString()).TrimEnd('&'); writer.WriteAttribute("href", pageUrl); if (!string.IsNullOrEmpty(PageLinkCssClass)) writer.WriteAttribute("class", PageLinkCssClass); writer.Write(HtmlTextWriter.SelfClosingTagEnd); writer.Write(i.ToString()); writer.WriteEndTag("a"); } writer.Write("\r\n"); } // write out last page link if (ShowFirstAndLastPageLinks && _endPage < TotalPages) { writer.WriteBeginTag("a"); string pageUrl = StringUtils.SetUrlEncodedKey(BaseUrl, QueryStringPageField, TotalPages.ToString()); writer.WriteAttribute("href", pageUrl); if (!string.IsNullOrEmpty(PageLinkCssClass)) writer.WriteAttribute("class", PageLinkCssClass + " " + PageLinkCssClass + "-last"); writer.Write(HtmlTextWriter.SelfClosingTagEnd); writer.Write(TotalPages.ToString()); writer.WriteEndTag("a"); } // Previous link if (ShowPreviousNextLinks && !string.IsNullOrEmpty(PreviousText) && ActivePage > 1) { writer.Write("&nbsp;"); writer.WriteBeginTag("a"); string pageUrl = StringUtils.SetUrlEncodedKey(BaseUrl, QueryStringPageField, (ActivePage - 1).ToString()); writer.WriteAttribute("href", pageUrl); if (!string.IsNullOrEmpty(PageLinkCssClass)) writer.WriteAttribute("class", PageLinkCssClass + " " + PageLinkCssClass + "-prev"); writer.Write(HtmlTextWriter.SelfClosingTagEnd); writer.Write(PreviousText); writer.WriteEndTag("a"); } // Next link if (ShowPreviousNextLinks && !string.IsNullOrEmpty(NextText) && ActivePage < TotalPages) { writer.Write("&nbsp;"); writer.WriteBeginTag("a"); string pageUrl = StringUtils.SetUrlEncodedKey(BaseUrl, QueryStringPageField, (ActivePage + 1).ToString()); writer.WriteAttribute("href", pageUrl); if (!string.IsNullOrEmpty(PageLinkCssClass)) writer.WriteAttribute("class", PageLinkCssClass + " " + PageLinkCssClass + "-next"); writer.Write(HtmlTextWriter.SelfClosingTagEnd); writer.Write(NextText); writer.WriteEndTag("a"); } writer.WriteEndTag("div"); if (RenderContainerDiv) { if (RenderContainerDivBreak) writer.Write("<br clear=\"all\" />\r\n"); writer.WriteEndTag("div"); } } As I said pretty much brute force rendering based on the control’s property settings of which there are quite a few: You can also see the pager in the designer above. unfortunately the VS designer (both 2010 and 2008) fails to render the float: left CSS styles properly and starts wrapping after margins are applied in the special buttons. Not a big deal since VS does at least respect the spacing (the floated elements overlay). Then again I’m not using the designer anyway :-}. Filtering Data What makes the Pager easy to use is the filter methods built into the control. While this functionality is clearly not the most politically correct design choice as it violates separation of concerns, it’s very useful for typical pager operation. While I actually have filter methods that do something similar in my business layer, having it exposed on the control makes the control a lot more useful for typical databinding scenarios. Of course these methods are optional – if you have a business layer that can provide filtered page queries for you can use that instead and assign the TotalItems property manually. There are three filter method types available for IQueryable, IEnumerable and for DataTable which tend to be the most common use cases in my apps old and new. The IQueryable version is pretty simple as it can simply rely on on .Skip() and .Take() with LINQ: /// <summary> /// <summary> /// Queries the database for the ActivePage applied manually /// or from the Request["page"] variable. This routine /// figures out and sets TotalPages, ActivePage and /// returns a filtered subset IQueryable that contains /// only the items from the ActivePage. /// </summary> /// <param name="query"></param> /// <param name="activePage"> /// The page you want to display. Sets the ActivePage property when passed. /// Pass 0 or smaller to use ActivePage setting. /// </param> /// <returns></returns> public IQueryable<T> FilterIQueryable<T>(IQueryable<T> query, int activePage) where T : class, new() { ActivePage = activePage < 1 ? ActivePage : activePage; if (ActivePage < 1) ActivePage = 1; TotalItems = query.Count(); if (TotalItems <= PageSize) { ActivePage = 1; TotalPages = 1; return query; } int skip = ActivePage - 1; if (skip > 0) query = query.Skip(skip * PageSize); _TotalPages = CalculateTotalPagesFromTotalItems(); return query.Take(PageSize); } The IEnumerable<T> version simply  converts the IEnumerable to an IQuerable and calls back into this method for filtering. The DataTable version requires a little more work to manually parse and filter records (I didn’t want to add the Linq DataSetExtensions assembly just for this): /// <summary> /// Filters a data table for an ActivePage. /// /// Note: Modifies the data set permanently by remove DataRows /// </summary> /// <param name="dt">Full result DataTable</param> /// <param name="activePage">Page to display. 0 to use ActivePage property </param> /// <returns></returns> public DataTable FilterDataTable(DataTable dt, int activePage) { ActivePage = activePage < 1 ? ActivePage : activePage; if (ActivePage < 1) ActivePage = 1; TotalItems = dt.Rows.Count; if (TotalItems <= PageSize) { ActivePage = 1; TotalPages = 1; return dt; } int skip = ActivePage - 1; if (skip > 0) { for (int i = 0; i < skip * PageSize; i++ ) dt.Rows.RemoveAt(0); } while(dt.Rows.Count > PageSize) dt.Rows.RemoveAt(PageSize); return dt; } Using the Pager Control The pager as it is is a first cut I built a couple of weeks ago and since then have been tweaking a little as part of an internal project I’m working on. I’ve replaced a bunch of pagers on various older pages with this pager without any issues and have what now feels like a more consistent user interface where paging looks and feels the same across different controls. As a bonus I’m only loading the data from the database that I need to display a single page. With the preset class tags applied too adding a pager is now as easy as dropping the control and adding the style sheet for styling to be consistent – no fuss, no muss. Schweet. Hopefully some of you may find this as useful as I have or at least as a baseline to build ontop of… Resources The Pager is part of the West Wind Web & Ajax Toolkit Pager.cs Source Code (some toolkit dependencies) Westwind.css base stylesheet with .pager and .gridpager styles Pager Example Page © Rick Strahl, West Wind Technologies, 2005-2010Posted in ASP.NET  

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• SimpleMembership, Membership Providers, Universal Providers and the new ASP.NET 4.5 Web Forms and ASP.NET MVC 4 templates

  - by Jon Galloway

  The ASP.NET MVC 4 Internet template adds some new, very useful features which are built on top of SimpleMembership. These changes add some great features, like a much simpler and extensible membership API and support for OAuth. However, the new account management features require SimpleMembership and won't work against existing ASP.NET Membership Providers. I'll start with a summary of top things you need to know, then dig into a lot more detail. Summary: SimpleMembership has been designed as a replacement for traditional the previous ASP.NET Role and Membership provider system SimpleMembership solves common problems people ran into with the Membership provider system and was designed for modern user / membership / storage needs SimpleMembership integrates with the previous membership system, but you can't use a MembershipProvider with SimpleMembership The new ASP.NET MVC 4 Internet application template AccountController requires SimpleMembership and is not compatible with previous MembershipProviders You can continue to use existing ASP.NET Role and Membership providers in ASP.NET 4.5 and ASP.NET MVC 4 - just not with the ASP.NET MVC 4 AccountController The existing ASP.NET Role and Membership provider system remains supported as is part of the ASP.NET core ASP.NET 4.5 Web Forms does not use SimpleMembership; it implements OAuth on top of ASP.NET Membership The ASP.NET Web Site Administration Tool (WSAT) is not compatible with SimpleMembership The following is the result of a few conversations with Erik Porter (PM for ASP.NET MVC) to make sure I had some the overall details straight, combined with a lot of time digging around in ILSpy and Visual Studio's assembly browsing tools. SimpleMembership: The future of membership for ASP.NET The ASP.NET Membership system was introduces with ASP.NET 2.0 back in 2005. It was designed to solve common site membership requirements at the time, which generally involved username / password based registration and profile storage in SQL Server. It was designed with a few extensibility mechanisms - notably a provider system (which allowed you override some specifics like backing storage) and the ability to store additional profile information (although the additional  profile information was packed into a single column which usually required access through the API). While it's sometimes frustrating to work with, it's held up for seven years - probably since it handles the main use case (username / password based membership in a SQL Server database) smoothly and can be adapted to most other needs (again, often frustrating, but it can work). The ASP.NET Web Pages and WebMatrix efforts allowed the team an opportunity to take a new look at a lot of things - e.g. the Razor syntax started with ASP.NET Web Pages, not ASP.NET MVC. The ASP.NET Web Pages team designed SimpleMembership to (wait for it) simplify the task of dealing with membership. As Matthew Osborn said in his post Using SimpleMembership With ASP.NET WebPages: With the introduction of ASP.NET WebPages and the WebMatrix stack our team has really be focusing on making things simpler for the developer. Based on a lot of customer feedback one of the areas that we wanted to improve was the built in security in ASP.NET. So with this release we took that time to create a new built in (and default for ASP.NET WebPages) security provider. I say provider because the new stuff is still built on the existing ASP.NET framework. So what do we call this new hotness that we have created? Well, none other than SimpleMembership. SimpleMembership is an umbrella term for both SimpleMembership and SimpleRoles. Part of simplifying membership involved fixing some common problems with ASP.NET Membership. Problems with ASP.NET Membership ASP.NET Membership was very obviously designed around a set of assumptions: Users and user information would most likely be stored in a full SQL Server database or in Active Directory User and profile information would be optimized around a set of common attributes (UserName, Password, IsApproved, CreationDate, Comment, Role membership...) and other user profile information would be accessed through a profile provider Some problems fall out of these assumptions. Requires Full SQL Server for default cases The default, and most fully featured providers ASP.NET Membership providers (SQL Membership Provider, SQL Role Provider, SQL Profile Provider) require full SQL Server. They depend on stored procedure support, and they rely on SQL Server cache dependencies, they depend on agents for clean up and maintenance. So the main SQL Server based providers don't work well on SQL Server CE, won't work out of the box on SQL Azure, etc. Note: Cory Fowler recently let me know about these Updated ASP.net scripts for use with Microsoft SQL Azure which do support membership, personalization, profile, and roles. But the fact that we need a support page with a set of separate SQL scripts underscores the underlying problem. Aha, you say! Jon's forgetting the Universal Providers, a.k.a. System.Web.Providers! Hold on a bit, we'll get to those... Custom Membership Providers have to work with a SQL-Server-centric API If you want to work with another database or other membership storage system, you need to to inherit from the provider base classes and override a bunch of methods which are tightly focused on storing a MembershipUser in a relational database. It can be done (and you can often find pretty good ones that have already been written), but it's a good amount of work and often leaves you with ugly code that has a bunch of System.NotImplementedException fun since there are a lot of methods that just don't apply. Designed around a specific view of users, roles and profiles The existing providers are focused on traditional membership - a user has a username and a password, some specific roles on the site (e.g. administrator, premium user), and may have some additional "nice to have" optional information that can be accessed via an API in your application. This doesn't fit well with some modern usage patterns: In OAuth and OpenID, the user doesn't have a password Often these kinds of scenarios map better to user claims or rights instead of monolithic user roles For many sites, profile or other non-traditional information is very important and needs to come from somewhere other than an API call that maps to a database blob What would work a lot better here is a system in which you were able to define your users, rights, and other attributes however you wanted and the membership system worked with your model - not the other way around. Requires specific schema, overflow in blob columns I've already mentioned this a few times, but it bears calling out separately - ASP.NET Membership focuses on SQL Server storage, and that storage is based on a very specific database schema. SimpleMembership as a better membership system As you might have guessed, SimpleMembership was designed to address the above problems. Works with your Schema As Matthew Osborn explains in his Using SimpleMembership With ASP.NET WebPages post, SimpleMembership is designed to integrate with your database schema: All SimpleMembership requires is that there are two columns on your users table so that we can hook up to it – an “ID” column and a “username” column. The important part here is that they can be named whatever you want. For instance username doesn't have to be an alias it could be an email column you just have to tell SimpleMembership to treat that as the “username” used to log in. Matthew's example shows using a very simple user table named Users (it could be named anything) with a UserID and Username column, then a bunch of other columns he wanted in his app. Then we point SimpleMemberhip at that table with a one-liner: WebSecurity.InitializeDatabaseFile("SecurityDemo.sdf", "Users", "UserID", "Username", true); No other tables are needed, the table can be named anything we want, and can have pretty much any schema we want as long as we've got an ID and something that we can map to a username. Broaden database support to the whole SQL Server family While SimpleMembership is not database agnostic, it works across the SQL Server family. It continues to support full SQL Server, but it also works with SQL Azure, SQL Server CE, SQL Server Express, and LocalDB. Everything's implemented as SQL calls rather than requiring stored procedures, views, agents, and change notifications. Note that SimpleMembership still requires some flavor of SQL Server - it won't work with MySQL, NoSQL databases, etc. You can take a look at the code in WebMatrix.WebData.dll using a tool like ILSpy if you'd like to see why - there places where SQL Server specific SQL statements are being executed, especially when creating and initializing tables. It seems like you might be able to work with another database if you created the tables separately, but I haven't tried it and it's not supported at this point. Note: I'm thinking it would be possible for SimpleMembership (or something compatible) to run Entity Framework so it would work with any database EF supports. That seems useful to me - thoughts? Note: SimpleMembership has the same database support - anything in the SQL Server family - that Universal Providers brings to the ASP.NET Membership system. Easy to with Entity Framework Code First The problem with with ASP.NET Membership's system for storing additional account information is that it's the gate keeper. That means you're stuck with its schema and accessing profile information through its API. SimpleMembership flips that around by allowing you to use any table as a user store. That means you're in control of the user profile information, and you can access it however you'd like - it's just data. Let's look at a practical based on the AccountModel.cs class in an ASP.NET MVC 4 Internet project. Here I'm adding a Birthday property to the UserProfile class. [Table("UserProfile")] public class UserProfile { [Key] [DatabaseGeneratedAttribute(DatabaseGeneratedOption.Identity)] public int UserId { get; set; } public string UserName { get; set; } public DateTime Birthday { get; set; } } Now if I want to access that information, I can just grab the account by username and read the value. var context = new UsersContext(); var username = User.Identity.Name; var user = context.UserProfiles.SingleOrDefault(u => u.UserName == username); var birthday = user.Birthday; So instead of thinking of SimpleMembership as a big membership API, think of it as something that handles membership based on your user database. In SimpleMembership, everything's keyed off a user row in a table you define rather than a bunch of entries in membership tables that were out of your control. How SimpleMembership integrates with ASP.NET Membership Okay, enough sales pitch (and hopefully background) on why things have changed. How does this affect you? Let's start with a diagram to show the relationship (note: I've simplified by removing a few classes to show the important relationships): So SimpleMembershipProvider is an implementaiton of an ExtendedMembershipProvider, which inherits from MembershipProvider and adds some other account / OAuth related things. Here's what ExtendedMembershipProvider adds to MembershipProvider: The important thing to take away here is that a SimpleMembershipProvider is a MembershipProvider, but a MembershipProvider is not a SimpleMembershipProvider. This distinction is important in practice: you cannot use an existing MembershipProvider (including the Universal Providers found in System.Web.Providers) with an API that requires a SimpleMembershipProvider, including any of the calls in WebMatrix.WebData.WebSecurity or Microsoft.Web.WebPages.OAuth.OAuthWebSecurity. However, that's as far as it goes. Membership Providers still work if you're accessing them through the standard Membership API, and all of the core stuff  - including the AuthorizeAttribute, role enforcement, etc. - will work just fine and without any change. Let's look at how that affects you in terms of the new templates. Membership in the ASP.NET MVC 4 project templates ASP.NET MVC 4 offers six Project Templates: Empty - Really empty, just the assemblies, folder structure and a tiny bit of basic configuration. Basic - Like Empty, but with a bit of UI preconfigured (css / images / bundling). Internet - This has both a Home and Account controller and associated views. The Account Controller supports registration and login via either local accounts and via OAuth / OpenID providers. Intranet - Like the Internet template, but it's preconfigured for Windows Authentication. Mobile - This is preconfigured using jQuery Mobile and is intended for mobile-only sites. Web API - This is preconfigured for a service backend built on ASP.NET Web API. Out of these templates, only one (the Internet template) uses SimpleMembership. ASP.NET MVC 4 Basic template The Basic template has configuration in place to use ASP.NET Membership with the Universal Providers. You can see that configuration in the ASP.NET MVC 4 Basic template's web.config: <profile defaultProvider="DefaultProfileProvider"> <providers> <add name="DefaultProfileProvider" type="System.Web.Providers.DefaultProfileProvider, System.Web.Providers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" connectionStringName="DefaultConnection" applicationName="/" /> </providers> </profile> <membership defaultProvider="DefaultMembershipProvider"> <providers> <add name="DefaultMembershipProvider" type="System.Web.Providers.DefaultMembershipProvider, System.Web.Providers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" connectionStringName="DefaultConnection" enablePasswordRetrieval="false" enablePasswordReset="true" requiresQuestionAndAnswer="false" requiresUniqueEmail="false" maxInvalidPasswordAttempts="5" minRequiredPasswordLength="6" minRequiredNonalphanumericCharacters="0" passwordAttemptWindow="10" applicationName="/" /> </providers> </membership> <roleManager defaultProvider="DefaultRoleProvider"> <providers> <add name="DefaultRoleProvider" type="System.Web.Providers.DefaultRoleProvider, System.Web.Providers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" connectionStringName="DefaultConnection" applicationName="/" /> </providers> </roleManager> <sessionState mode="InProc" customProvider="DefaultSessionProvider"> <providers> <add name="DefaultSessionProvider" type="System.Web.Providers.DefaultSessionStateProvider, System.Web.Providers, Version=1.0.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" connectionStringName="DefaultConnection" /> </providers> </sessionState> This means that it's business as usual for the Basic template as far as ASP.NET Membership works. ASP.NET MVC 4 Internet template The Internet template has a few things set up to bootstrap SimpleMembership: \Models\AccountModels.cs defines a basic user account and includes data annotations to define keys and such \Filters\InitializeSimpleMembershipAttribute.cs creates the membership database using the above model, then calls WebSecurity.InitializeDatabaseConnection which verifies that the underlying tables are in place and marks initialization as complete (for the application's lifetime) \Controllers\AccountController.cs makes heavy use of OAuthWebSecurity (for OAuth account registration / login / management) and WebSecurity. WebSecurity provides account management services for ASP.NET MVC (and Web Pages) WebSecurity can work with any ExtendedMembershipProvider. There's one in the box (SimpleMembershipProvider) but you can write your own. Since a standard MembershipProvider is not an ExtendedMembershipProvider, WebSecurity will throw exceptions if the default membership provider is a MembershipProvider rather than an ExtendedMembershipProvider. Practical example: Create a new ASP.NET MVC 4 application using the Internet application template Install the Microsoft ASP.NET Universal Providers for LocalDB NuGet package Run the application, click on Register, add a username and password, and click submit You'll get the following execption in AccountController.cs::Register: To call this method, the "Membership.Provider" property must be an instance of "ExtendedMembershipProvider". This occurs because the ASP.NET Universal Providers packages include a web.config transform that will update your web.config to add the Universal Provider configuration I showed in the Basic template example above. When WebSecurity tries to use the configured ASP.NET Membership Provider, it checks if it can be cast to an ExtendedMembershipProvider before doing anything else. So, what do you do? Options: If you want to use the new AccountController, you'll either need to use the SimpleMembershipProvider or another valid ExtendedMembershipProvider. This is pretty straightforward. If you want to use an existing ASP.NET Membership Provider in ASP.NET MVC 4, you can't use the new AccountController. You can do a few things: Replace  the AccountController.cs and AccountModels.cs in an ASP.NET MVC 4 Internet project with one from an ASP.NET MVC 3 application (you of course won't have OAuth support). Then, if you want, you can go through and remove other things that were built around SimpleMembership - the OAuth partial view, the NuGet packages (e.g. the DotNetOpenAuthAuth package, etc.) Use an ASP.NET MVC 4 Internet application template and add in a Universal Providers NuGet package. Then copy in the AccountController and AccountModel classes. Create an ASP.NET MVC 3 project and upgrade it to ASP.NET MVC 4 using the steps shown in the ASP.NET MVC 4 release notes. None of these are particularly elegant or simple. Maybe we (or just me?) can do something to make this simpler - perhaps a NuGet package. However, this should be an edge case - hopefully the cases where you'd need to create a new ASP.NET but use legacy ASP.NET Membership Providers should be pretty rare. Please let me (or, preferably the team) know if that's an incorrect assumption. Membership in the ASP.NET 4.5 project template ASP.NET 4.5 Web Forms took a different approach which builds off ASP.NET Membership. Instead of using the WebMatrix security assemblies, Web Forms uses Microsoft.AspNet.Membership.OpenAuth assembly. I'm no expert on this, but from a bit of time in ILSpy and Visual Studio's (very pretty) dependency graphs, this uses a Membership Adapter to save OAuth data into an EF managed database while still running on top of ASP.NET Membership. Note: There may be a way to use this in ASP.NET MVC 4, although it would probably take some plumbing work to hook it up. How does this fit in with Universal Providers (System.Web.Providers)? Just to summarize: Universal Providers are intended for cases where you have an existing ASP.NET Membership Provider and you want to use it with another SQL Server database backend (other than SQL Server). It doesn't require agents to handle expired session cleanup and other background tasks, it piggybacks these tasks on other calls. Universal Providers are not really, strictly speaking, universal - at least to my way of thinking. They only work with databases in the SQL Server family. Universal Providers do not work with Simple Membership. The Universal Providers packages include some web config transforms which you would normally want when you're using them. What about the Web Site Administration Tool? Visual Studio includes tooling to launch the Web Site Administration Tool (WSAT) to configure users and roles in your application. WSAT is built to work with ASP.NET Membership, and is not compatible with Simple Membership. There are two main options there: Use the WebSecurity and OAuthWebSecurity API to manage the users and roles Create a web admin using the above APIs Since SimpleMembership runs on top of your database, you can update your users as you would any other data - via EF or even in direct database edits (in development, of course)

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• Building applications with WPF, MVVM and Prism(aka CAG)

  - by skjagini

  In this article I am going to walk through an application using WPF and Prism (aka composite application guidance, CAG) which simulates engaging a taxi (cab).  The rules are simple, the app would have3 screens A login screen to authenticate the user An information screen. A screen to engage the cab and roam around and calculating the total fare Metered Rate of Fare The meter is required to be engaged when a cab is occupied by anyone $3.00 upon entry $0.35 for each additional unit The unit fare is: one-fifth of a mile, when the cab is traveling at 6 miles an hour or more; or 60 seconds when not in motion or traveling at less than 12 miles per hour. Night surcharge of $.50 after 8:00 PM & before 6:00 AM Peak hour Weekday Surcharge of $1.00 Monday - Friday after 4:00 PM & before 8:00 PM New York State Tax Surcharge of $.50 per ride. Example: Friday (2010-10-08) 5:30pm Start at Lexington Ave & E 57th St End at Irving Pl & E 15th St Start = $3.00 Travels 2 miles at less than 6 mph for 15 minutes = $3.50 Travels at more than 12 mph for 5 minutes = $1.75 Peak hour Weekday Surcharge = $1.00 (ride started at 5:30 pm) New York State Tax Surcharge = $0.50 Before we dive into the app, I would like to give brief description about the framework.  If you want to jump on to the source code, scroll all the way to the end of the post. MVVM MVVM pattern is in no way related to the usage of PRISM in your application and should be considered if you are using WPF irrespective of PRISM or not. Lets say you are not familiar with MVVM, your typical UI would involve adding some UI controls like text boxes, a button, double clicking on the button,  generating event handler, calling a method from business layer and updating the user interface, it works most of the time for developing small scale applications. The problem with this approach is that there is some amount of code specific to business logic wrapped in UI specific code which is hard to unit test it, mock it and MVVM helps to solve the exact problem. MVVM stands for Model(M) – View(V) – ViewModel(VM),  based on the interactions with in the three parties it should be called VVMM,  MVVM sounds more like MVC (Model-View-Controller) so the name. Why it should be called VVMM: View – View Model - Model WPF allows to create user interfaces using XAML and MVVM takes it to the next level by allowing complete separation of user interface and business logic. In WPF each view will have a property, DataContext when set to an instance of a class (which happens to be your view model) provides the data the view is interested in, i.e., view interacts with view model and at the same time view model interacts with view through DataContext. Sujith, if view and view model are interacting directly with each other how does MVVM is helping me separation of concerns? Well, the catch is DataContext is of type Object, since it is of type object view doesn’t know exact type of view model allowing views and views models to be loosely coupled. View models aggregate data from models (data access layer, services, etc) and make it available for views through properties, methods etc, i.e., View Models interact with Models. PRISM Prism is provided by Microsoft Patterns and Practices team and it can be downloaded from codeplex for source code,  samples and documentation on msdn.  The name composite implies, to compose user interface from different modules (views) without direct dependencies on each other, again allowing  loosely coupled development. Well Sujith, I can already do that with user controls, why shall I learn another framework?  That’s correct, you can decouple using user controls, but you still have to manage some amount of coupling, like how to do you communicate between the controls, how do you subscribe/unsubscribe, loading/unloading views dynamically. Prism is not a replacement for user controls, provides the following features which greatly help in designing the composite applications. Dependency Injection (DI)/ Inversion of Control (IoC) Modules Regions Event Aggregator  Commands Simply put, MVVM helps building a single view and Prism helps building an application using the views There are other open source alternatives to Prism, like MVVMLight, Cinch, take a look at them as well. Lets dig into the source code.  1. Solution The solution is made of the following projects Framework: Holds the common functionality in building applications using WPF and Prism TaxiClient: Start up project, boot strapping and app styling TaxiCommon: Helps with the business logic TaxiModules: Holds the meat of the application with views and view models TaxiTests: To test the application 2. DI / IoC Dependency Injection (DI) as the name implies refers to injecting dependencies and Inversion of Control (IoC) means the calling code has no direct control on the dependencies, opposite of normal way of programming where dependencies are passed by caller, i.e inversion; aside from some differences in terminology the concept is same in both the cases. The idea behind DI/IoC pattern is to reduce the amount of direct coupling between different components of the application, the higher the dependency the more tightly coupled the application resulting in code which is hard to modify, unit test and mock.  Initializing Dependency Injection through BootStrapper TaxiClient is the starting project of the solution and App (App.xaml)  is the starting class that gets called when you run the application. From the App’s OnStartup method we will invoke BootStrapper.   namespace TaxiClient { /// <summary> /// Interaction logic for App.xaml /// </summary> public partial class App : Application { protected override void OnStartup(StartupEventArgs e) { base.OnStartup(e);   (new BootStrapper()).Run(); } } } BootStrapper is your contact point for initializing the application including dependency injection, creating Shell and other frameworks. We are going to use Unity for DI and there are lot of open source DI frameworks like Spring.Net, StructureMap etc with different feature set  and you can choose a framework based on your preferences. Note that Prism comes with in built support for Unity, for example we are deriving from UnityBootStrapper in our case and for any other DI framework you have to extend the Prism appropriately   namespace TaxiClient { public class BootStrapper: UnityBootstrapper { protected override IModuleCatalog CreateModuleCatalog() { return new ConfigurationModuleCatalog(); } protected override DependencyObject CreateShell() { Framework.FrameworkBootStrapper.Run(Container, Application.Current.Dispatcher);   Shell shell = new Shell(); shell.ResizeMode = ResizeMode.NoResize; shell.Show();   return shell; } } } Lets take a look into  FrameworkBootStrapper to check out how to register with unity container. namespace Framework { public class FrameworkBootStrapper { public static void Run(IUnityContainer container, Dispatcher dispatcher) { UIDispatcher uiDispatcher = new UIDispatcher(dispatcher); container.RegisterInstance<IDispatcherService>(uiDispatcher);   container.RegisterType<IInjectSingleViewService, InjectSingleViewService>( new ContainerControlledLifetimeManager());   . . . } } } In the above code we are registering two components with unity container. You shall observe that we are following two different approaches, RegisterInstance and RegisterType.  With RegisterInstance we are registering an existing instance and the same instance will be returned for every request made for IDispatcherService   and with RegisterType we are requesting unity container to create an instance for us when required, i.e., when I request for an instance for IInjectSingleViewService, unity will create/return an instance of InjectSingleViewService class and with RegisterType we can configure the life time of the instance being created. With ContaienrControllerLifetimeManager, the unity container caches the instance and reuses for any subsequent requests, without recreating a new instance. Lets take a look into FareViewModel.cs and it’s constructor. The constructor takes one parameter IEventAggregator and if you try to find all references in your solution for IEventAggregator, you will not find a single location where an instance of EventAggregator is passed directly to the constructor. The compiler still finds an instance and works fine because Prism is already configured when used with Unity container to return an instance of EventAggregator when requested for IEventAggregator and in this particular case it is called constructor injection. public class FareViewModel:ObservableBase, IDataErrorInfo { ... private IEventAggregator _eventAggregator;   public FareViewModel(IEventAggregator eventAggregator) { _eventAggregator = eventAggregator; InitializePropertyNames(); InitializeModel(); PropertyChanged += OnPropertyChanged; } ... 3. Shell Shells are very similar in operation to Master Pages in asp.net or MDI in Windows Forms. And shells contain regions which display the views, you can have as many regions as you wish in a given view. You can also nest regions. i.e, one region can load a view which in itself may contain other regions. We have to create a shell at the start of the application and are doing it by overriding CreateShell method from BootStrapper From the following Shell.xaml you shall notice that we have two content controls with Region names as ‘MenuRegion’ and ‘MainRegion’.  The idea here is that you can inject any user controls into the regions dynamically, i.e., a Menu User Control for MenuRegion and based on the user action you can load appropriate view into MainRegion.    <Window x:Class="TaxiClient.Shell" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:Regions="clr-namespace:Microsoft.Practices.Prism.Regions;assembly=Microsoft.Practices.Prism" Title="Taxi" Height="370" Width="800"> <Grid Margin="2"> <ContentControl Regions:RegionManager.RegionName="MenuRegion" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch" />   <ContentControl Grid.Row="1" Regions:RegionManager.RegionName="MainRegion" HorizontalAlignment="Stretch" VerticalAlignment="Stretch" HorizontalContentAlignment="Stretch" VerticalContentAlignment="Stretch" /> <!--<Border Grid.ColumnSpan="2" BorderThickness="2" CornerRadius="3" BorderBrush="LightBlue" />-->   </Grid> </Window> 4. Modules Prism provides the ability to build composite applications and modules play an important role in it. For example if you are building a Mortgage Loan Processor application with 3 components, i.e. customer’s credit history,  existing mortgages, new home/loan information; and consider that the customer’s credit history component involves gathering data about his/her address, background information, job details etc. The idea here using Prism modules is to separate the implementation of these 3 components into their own visual studio projects allowing to build components with no dependency on each other and independently. If we need to add another component to the application, the component can be developed by in house team or some other team in the organization by starting with a new Visual Studio project and adding to the solution at the run time with very little knowledge about the application. Prism modules are defined by implementing the IModule interface and each visual studio project to be considered as a module should implement the IModule interface.  From the BootStrapper.cs you shall observe that we are overriding the method by returning a ConfiguratingModuleCatalog which returns the modules that are registered for the application using the app.config file  and you can also add module using code. Lets take a look into configuration file.   <?xml version="1.0"?> <configuration> <configSections> <section name="modules" type="Microsoft.Practices.Prism.Modularity.ModulesConfigurationSection, Microsoft.Practices.Prism"/> </configSections> <modules> <module assemblyFile="TaxiModules.dll" moduleType="TaxiModules.ModuleInitializer, TaxiModules" moduleName="TaxiModules"/> </modules> </configuration> Here we are adding TaxiModules project to our solution and TaxiModules.ModuleInitializer implements IModule interface   5. Module Mapper With Prism modules you can dynamically add or remove modules from the regions, apart from that Prism also provides API to control adding/removing the views from a region within the same module. Taxi Information Screen: Engage the Taxi Screen: The sample application has two screens, ‘Taxi Information’ and ‘Engage the Taxi’ and they both reside in same module, TaxiModules. ‘Engage the Taxi’ is again made of two user controls, FareView on the left and TotalView on the right. We have created a Shell with two regions, MenuRegion and MainRegion with menu loaded into MenuRegion. We can create a wrapper user control called EngageTheTaxi made of FareView and TotalView and load either TaxiInfo or EngageTheTaxi into MainRegion based on the user action. Though it will work it tightly binds the user controls and for every combination of user controls, we need to create a dummy wrapper control to contain them. Instead we can apply the principles we learned so far from Shell/regions and introduce another template (LeftAndRightRegionView.xaml) made of two regions Region1 (left) and Region2 (right) and load  FareView and TotalView dynamically.  To help with loading of the views dynamically I have introduce an helper an interface, IInjectSingleViewService,  idea suggested by Mike Taulty, a must read blog for .Net developers. using System; using System.Collections.Generic; using System.ComponentModel;   namespace Framework.PresentationUtility.Navigation {   public interface IInjectSingleViewService : INotifyPropertyChanged { IEnumerable<CommandViewDefinition> Commands { get; } IEnumerable<ModuleViewDefinition> Modules { get; }   void RegisterViewForRegion(string commandName, string viewName, string regionName, Type viewType); void ClearViewFromRegion(string viewName, string regionName); void RegisterModule(string moduleName, IList<ModuleMapper> moduleMappers); } } The Interface declares three methods to work with views: RegisterViewForRegion: Registers a view with a particular region. You can register multiple views and their regions under one command.  When this particular command is invoked all the views registered under it will be loaded into their regions. ClearViewFromRegion: To unload a specific view from a region. RegisterModule: The idea is when a command is invoked you can load the UI with set of controls in their default position and based on the user interaction, you can load different contols in to different regions on the fly.  And it is supported ModuleViewDefinition and ModuleMappers as shown below. namespace Framework.PresentationUtility.Navigation { public class ModuleViewDefinition { public string ModuleName { get; set; } public IList<ModuleMapper> ModuleMappers; public ICommand Command { get; set; } }   public class ModuleMapper { public string ViewName { get; set; } public string RegionName { get; set; } public Type ViewType { get; set; } } } 6. Event Aggregator Prism event aggregator enables messaging between components as in Observable pattern, Notifier notifies the Observer which receives notification it is interested in. When it comes to Observable pattern, Observer has to unsubscribes for notifications when it no longer interested in notifications, which allows the Notifier to remove the Observer’s reference from it’s local cache. Though .Net has managed garbage collection it cannot remove inactive the instances referenced by an active instance resulting in memory leak, keeping the Observers in memory as long as Notifier stays in memory.  Developers have to be very careful to unsubscribe when necessary and it often gets overlooked, to overcome these problems Prism Event Aggregator uses weak references to cache the reference (Observer in this case)  and releases the reference (memory) once the instance goes out of scope. Using event aggregator is very simple, declare a generic type of CompositePresenationEvent by inheriting from it. using Microsoft.Practices.Prism.Events; using TaxiCommon.BAO;   namespace TaxiCommon.CompositeEvents { public class TaxiOnMoveEvent:CompositePresentationEvent<TaxiOnMove> { } }   TaxiOnMove.cs includes the properties which we want to exchange between the parties, FareView and TotalView. using System;   namespace TaxiCommon.BAO { public class TaxiOnMove { public TimeSpan MinutesAtTweleveMPH { get; set; } public double MilesAtSixMPH { get; set; } } }   Lets take a look into FareViewodel (Notifier) and how it raises the event.  Here we are raising the event by getting the event through GetEvent<..>() and publishing it with the payload private void OnAddMinutes(object obj) { TaxiOnMove payload = new TaxiOnMove(); if(MilesAtSixMPH != null) payload.MilesAtSixMPH = MilesAtSixMPH.Value; if(MinutesAtTweleveMPH != null) payload.MinutesAtTweleveMPH = new TimeSpan(0,0,MinutesAtTweleveMPH.Value,0);   _eventAggregator.GetEvent<TaxiOnMoveEvent>().Publish(payload); ResetMinutesAndMiles(); } And TotalViewModel(Observer) subscribes to notifications by getting the event through GetEvent<..>() namespace TaxiModules.ViewModels { public class TotalViewModel:ObservableBase { .... private IEventAggregator _eventAggregator;   public TotalViewModel(IEventAggregator eventAggregator) { _eventAggregator = eventAggregator; ... }   private void SubscribeToEvents() { _eventAggregator.GetEvent<TaxiStartedEvent>() .Subscribe(OnTaxiStarted, ThreadOption.UIThread,false,(filter) => true); _eventAggregator.GetEvent<TaxiOnMoveEvent>() .Subscribe(OnTaxiMove, ThreadOption.UIThread, false, (filter) => true); _eventAggregator.GetEvent<TaxiResetEvent>() .Subscribe(OnTaxiReset, ThreadOption.UIThread, false, (filter) => true); }   ... private void OnTaxiMove(TaxiOnMove taxiOnMove) { OnMoveFare fare = new OnMoveFare(taxiOnMove); Fares.Add(fare); SetTotalFare(new []{fare}); }   .... 7. MVVM through example In this section we are going to look into MVVM implementation through example.  I have all the modules declared in a single project, TaxiModules, again it is not necessary to have them into one project. Once the user logs into the application, will be greeted with the ‘Engage the Taxi’ screen which is made of two user controls, FareView.xaml and TotalView.Xaml. As you can see from the solution explorer, each of them have their own code behind files and  ViewModel classes, FareViewMode.cs, TotalViewModel.cs Lets take a look in to the FareView and how it interacts with FareViewModel using MVVM implementation. FareView.xaml acts as a view and FareViewMode.cs is it’s view model. The FareView code behind class   namespace TaxiModules.Views { /// <summary> /// Interaction logic for FareView.xaml /// </summary> public partial class FareView : UserControl { public FareView(FareViewModel viewModel) { InitializeComponent(); this.Loaded += (s, e) => { this.DataContext = viewModel; }; } } } The FareView is bound to FareViewModel through the data context  and you shall observe that DataContext is of type Object, i.e. the FareView doesn’t really know the type of ViewModel (FareViewModel). This helps separation of View and ViewModel as View and ViewModel are independent of each other, you can bind FareView to FareViewModel2 as well and the application compiles just fine. Lets take a look into FareView xaml file  <UserControl x:Class="TaxiModules.Views.FareView" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:Toolkit="clr-namespace:Microsoft.Windows.Controls;assembly=WPFToolkit" xmlns:Commands="clr-namespace:Microsoft.Practices.Prism.Commands;assembly=Microsoft.Practices.Prism"> <Grid Margin="10" > ....   <Border Style="{DynamicResource innerBorder}" Grid.Row="0" Grid.Column="0" Grid.RowSpan="11" Grid.ColumnSpan="2" Panel.ZIndex="1"/>   <Label Grid.Row="0" Content="Engage the Taxi" Style="{DynamicResource innerHeader}"/> <Label Grid.Row="1" Content="Select the State"/> <ComboBox Grid.Row="1" Grid.Column="1" ItemsSource="{Binding States}" Height="auto"> <ComboBox.ItemTemplate> <DataTemplate> <TextBlock Text="{Binding Name}"/> </DataTemplate> </ComboBox.ItemTemplate> <ComboBox.SelectedItem> <Binding Path="SelectedState" Mode="TwoWay"/> </ComboBox.SelectedItem> </ComboBox> <Label Grid.Row="2" Content="Select the Date of Entry"/> <Toolkit:DatePicker Grid.Row="2" Grid.Column="1" SelectedDate="{Binding DateOfEntry, ValidatesOnDataErrors=true}" /> <Label Grid.Row="3" Content="Enter time 24hr format"/> <TextBox Grid.Row="3" Grid.Column="1" Text="{Binding TimeOfEntry, TargetNullValue=''}"/> <Button Grid.Row="4" Grid.Column="1" Content="Start the Meter" Commands:Click.Command="{Binding StartMeterCommand}" />   <Label Grid.Row="5" Content="Run the Taxi" Style="{DynamicResource innerHeader}"/> <Label Grid.Row="6" Content="Number of Miles &lt;@6mph"/> <TextBox Grid.Row="6" Grid.Column="1" Text="{Binding MilesAtSixMPH, TargetNullValue='', ValidatesOnDataErrors=true}"/> <Label Grid.Row="7" Content="Number of Minutes @12mph"/> <TextBox Grid.Row="7" Grid.Column="1" Text="{Binding MinutesAtTweleveMPH, TargetNullValue=''}"/> <Button Grid.Row="8" Grid.Column="1" Content="Add Minutes and Miles " Commands:Click.Command="{Binding AddMinutesCommand}"/> <Label Grid.Row="9" Content="Other Operations" Style="{DynamicResource innerHeader}"/> <Button Grid.Row="10" Grid.Column="1" Content="Reset the Meter" Commands:Click.Command="{Binding ResetCommand}"/>   </Grid> </UserControl> The highlighted code from the above code shows data binding, for example ComboBox which displays list of states has it’s ItemsSource bound to States property, with DataTemplate bound to Name and SelectedItem  to SelectedState. You might be wondering what are all these properties and how it is able to bind to them.  The answer lies in data context, i.e., when you bound a control, WPF looks for data context on the root object (Grid in this case) and if it can’t find data context it will look into root’s root, i.e. FareView UserControl and it is bound to FareViewModel.  Each of those properties have be declared on the ViewModel for the View to bind correctly. To put simply, View is bound to ViewModel through data context of type object and every control that is bound on the View actually binds to the public property on the ViewModel. Lets look into the ViewModel code (the following code is not an exact copy of FareViewMode.cs, pasted relevant code for this section)   namespace TaxiModules.ViewModels { public class FareViewModel:ObservableBase, IDataErrorInfo { public List<USState> States { get { return USStates.StateList; } }   public USState SelectedState { get { return _selectedState; } set { _selectedState = value; RaisePropertyChanged(_selectedStatePropertyName); } }   public DateTime? DateOfEntry { get { return _dateOfEntry; } set { _dateOfEntry = value; RaisePropertyChanged(_dateOfEntryPropertyName); } }   public TimeSpan? TimeOfEntry { get { return _timeOfEntry; } set { _timeOfEntry = value; RaisePropertyChanged(_timeOfEntryPropertyName); } }   public double? MilesAtSixMPH { get { return _milesAtSixMPH; } set { _milesAtSixMPH = value; RaisePropertyChanged(_distanceAtSixMPHPropertyName); } }   public int? MinutesAtTweleveMPH { get { return _minutesAtTweleveMPH; } set { _minutesAtTweleveMPH = value; RaisePropertyChanged(_minutesAtTweleveMPHPropertyName); } }   public ICommand StartMeterCommand { get { if(_startMeterCommand == null) { _startMeterCommand = new DelegateCommand<object>(OnStartMeter, CanStartMeter); } return _startMeterCommand; } }   public ICommand AddMinutesCommand { get { if(_addMinutesCommand == null) { _addMinutesCommand = new DelegateCommand<object>(OnAddMinutes, CanAddMinutes); } return _addMinutesCommand; } }   public ICommand ResetCommand { get { if(_resetCommand == null) { _resetCommand = new DelegateCommand<object>(OnResetCommand); } return _resetCommand; } }   } private void OnStartMeter(object obj) { _eventAggregator.GetEvent<TaxiStartedEvent>().Publish( new TaxiStarted() { EngagedOn = DateOfEntry.Value.Date + TimeOfEntry.Value, EngagedState = SelectedState.Value });   _isMeterStarted = true; OnPropertyChanged(this,null); } And views communicate user actions like button clicks, tree view item selections, etc using commands. When user clicks on ‘Start the Meter’ button it invokes the method StartMeterCommand, which calls the method OnStartMeter which publishes the event to TotalViewModel using event aggregator  and TaxiStartedEvent. namespace TaxiModules.ViewModels { public class TotalViewModel:ObservableBase { ... private IEventAggregator _eventAggregator;   public TotalViewModel(IEventAggregator eventAggregator) { _eventAggregator = eventAggregator;   InitializePropertyNames(); InitializeModel(); SubscribeToEvents(); }   public decimal? TotalFare { get { return _totalFare; } set { _totalFare = value; RaisePropertyChanged(_totalFarePropertyName); } } .... private void SubscribeToEvents() { _eventAggregator.GetEvent<TaxiStartedEvent>().Subscribe(OnTaxiStarted, ThreadOption.UIThread,false,(filter) => true); _eventAggregator.GetEvent<TaxiOnMoveEvent>().Subscribe(OnTaxiMove, ThreadOption.UIThread, false, (filter) => true); _eventAggregator.GetEvent<TaxiResetEvent>().Subscribe(OnTaxiReset, ThreadOption.UIThread, false, (filter) => true); }   private void OnTaxiStarted(TaxiStarted taxiStarted) { Fares.Add(new EntryFare()); Fares.Add(new StateTaxFare(taxiStarted)); Fares.Add(new NightSurchargeFare(taxiStarted)); Fares.Add(new PeakHourWeekdayFare(taxiStarted));   SetTotalFare(Fares); }   private void SetTotalFare(IEnumerable<IFare> fares) { TotalFare = (_totalFare ?? 0) + TaxiFareHelper.GetTotalFare(fares); } ....   } }   TotalViewModel subscribes to events, TaxiStartedEvent and rest. When TaxiStartedEvent gets invoked it calls the OnTaxiStarted method which sets the total fare which includes entry fee, state tax, nightly surcharge, peak hour weekday fare.   Note that TotalViewModel derives from ObservableBase which implements the method RaisePropertyChanged which we are invoking in Set of TotalFare property, i.e, once we update the TotalFare property it raises an the event that  allows the TotalFare text box to fetch the new value through the data context. ViewModel is communicating with View through data context and it has no knowledge about View, helping in loose coupling of ViewModel and View.   I have attached the source code (.Net 4.0, Prism 4.0, VS 2010) , download and play with it and don’t forget to leave your comments.  

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• ASP.NET Web API Exception Handling

  - by Fredrik N

  When I talk about exceptions in my product team I often talk about two kind of exceptions, business and critical exceptions. Business exceptions are exceptions thrown based on “business rules”, for example if you aren’t allowed to do a purchase. Business exceptions in most case aren’t important to log into a log file, they can directly be shown to the user. An example of a business exception could be "DeniedToPurchaseException”, or some validation exceptions such as “FirstNameIsMissingException” etc. Critical Exceptions are all other kind of exceptions such as the SQL server is down etc. Those kind of exception message need to be logged and should not reach the user, because they can contain information that can be harmful if it reach out to wrong kind of users. I often distinguish business exceptions from critical exceptions by creating a base class called BusinessException, then in my error handling code I catch on the type BusinessException and all other exceptions will be handled as critical exceptions. This blog post will be about different ways to handle exceptions and how Business and Critical Exceptions could be handled. Web API and Exceptions the basics When an exception is thrown in a ApiController a response message will be returned with a status code set to 500 and a response formatted by the formatters based on the “Accept” or “Content-Type” HTTP header, for example JSON or XML. Here is an example:   public IEnumerable<string> Get() { throw new ApplicationException("Error!!!!!"); return new string[] { "value1", "value2" }; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The response message will be: HTTP/1.1 500 Internal Server Error Content-Length: 860 Content-Type: application/json; charset=utf-8 { "ExceptionType":"System.ApplicationException","Message":"Error!!!!!","StackTrace":" at ..."} .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   The stack trace will be returned to the client, this is because of making it easier to debug. Be careful so you don’t leak out some sensitive information to the client. So as long as you are developing your API, this is not harmful. In a production environment it can be better to log exceptions and return a user friendly exception instead of the original exception. There is a specific exception shipped with ASP.NET Web API that will not use the formatters based on the “Accept” or “Content-Type” HTTP header, it is the exception is the HttpResponseException class. Here is an example where the HttpReponseExcetpion is used: // GET api/values [ExceptionHandling] public IEnumerable<string> Get() { throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError)); return new string[] { "value1", "value2" }; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The response will not contain any content, only header information and the status code based on the HttpStatusCode passed as an argument to the HttpResponseMessage. Because the HttpResponsException takes a HttpResponseMessage as an argument, we can give the response a content: public IEnumerable<string> Get() { throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent("My Error Message"), ReasonPhrase = "Critical Exception" }); return new string[] { "value1", "value2" }; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   The code above will have the following response:   HTTP/1.1 500 Critical Exception Content-Length: 5 Content-Type: text/plain; charset=utf-8 My Error Message .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The Content property of the HttpResponseMessage doesn’t need to be just plain text, it can also be other formats, for example JSON, XML etc. By using the HttpResponseException we can for example catch an exception and throw a user friendly exception instead: public IEnumerable<string> Get() { try { DoSomething(); return new string[] { "value1", "value2" }; } catch (Exception e) { throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent("An error occurred, please try again or contact the administrator."), ReasonPhrase = "Critical Exception" }); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   Adding a try catch to every ApiController methods will only end in duplication of code, by using a custom ExceptionFilterAttribute or our own custom ApiController base class we can reduce code duplicationof code and also have a more general exception handler for our ApiControllers . By creating a custom ApiController’s and override the ExecuteAsync method, we can add a try catch around the base.ExecuteAsync method, but I prefer to skip the creation of a own custom ApiController, better to use a solution that require few files to be modified. The ExceptionFilterAttribute has a OnException method that we can override and add our exception handling. Here is an example: using System; using System.Diagnostics; using System.Net; using System.Net.Http; using System.Web.Http; using System.Web.Http.Filters; public class ExceptionHandlingAttribute : ExceptionFilterAttribute { public override void OnException(HttpActionExecutedContext context) { if (context.Exception is BusinessException) { throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent(context.Exception.Message), ReasonPhrase = "Exception" }); } //Log Critical errors Debug.WriteLine(context.Exception); throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent("An error occurred, please try again or contact the administrator."), ReasonPhrase = "Critical Exception" }); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   Note: Something to have in mind is that the ExceptionFilterAttribute will be ignored if the ApiController action method throws a HttpResponseException. The code above will always make sure a HttpResponseExceptions will be returned, it will also make sure the critical exceptions will show a more user friendly message. The OnException method can also be used to log exceptions. By using a ExceptionFilterAttribute the Get() method in the previous example can now look like this: public IEnumerable<string> Get() { DoSomething(); return new string[] { "value1", "value2" }; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } To use the an ExceptionFilterAttribute, we can for example add the ExceptionFilterAttribute to our ApiControllers methods or to the ApiController class definition, or register it globally for all ApiControllers. You can read more about is here. Note: If something goes wrong in the ExceptionFilterAttribute and an exception is thrown that is not of type HttpResponseException, a formatted exception will be thrown with stack trace etc to the client. How about using a custom IHttpActionInvoker? We can create our own IHTTPActionInvoker and add Exception handling to the invoker. The IHttpActionInvoker will be used to invoke the ApiController’s ExecuteAsync method. Here is an example where the default IHttpActionInvoker, ApiControllerActionInvoker, is used to add exception handling: public class MyApiControllerActionInvoker : ApiControllerActionInvoker { public override Task<HttpResponseMessage> InvokeActionAsync(HttpActionContext actionContext, System.Threading.CancellationToken cancellationToken) { var result = base.InvokeActionAsync(actionContext, cancellationToken); if (result.Exception != null && result.Exception.GetBaseException() != null) { var baseException = result.Exception.GetBaseException(); if (baseException is BusinessException) { return Task.Run<HttpResponseMessage>(() => new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent(baseException.Message), ReasonPhrase = "Error" }); } else { //Log critical error Debug.WriteLine(baseException); return Task.Run<HttpResponseMessage>(() => new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent(baseException.Message), ReasonPhrase = "Critical Error" }); } } return result; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } You can register the IHttpActionInvoker with your own IoC to resolve the MyApiContollerActionInvoker, or add it in the Global.asax: GlobalConfiguration.Configuration.Services.Remove(typeof(IHttpActionInvoker), GlobalConfiguration.Configuration.Services.GetActionInvoker()); GlobalConfiguration.Configuration.Services.Add(typeof(IHttpActionInvoker), new MyApiControllerActionInvoker()); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   How about using a Message Handler for Exception Handling? By creating a custom Message Handler, we can handle error after the ApiController and the ExceptionFilterAttribute is invoked and in that way create a global exception handler, BUT, the only thing we can take a look at is the HttpResponseMessage, we can’t add a try catch around the Message Handler’s SendAsync method. The last Message Handler that will be used in the Wep API pipe-line is the HttpControllerDispatcher and this Message Handler is added to the HttpServer in an early stage. The HttpControllerDispatcher will use the IHttpActionInvoker to invoke the ApiController method. The HttpControllerDipatcher has a try catch that will turn ALL exceptions into a HttpResponseMessage, so that is the reason why a try catch around the SendAsync in a custom Message Handler want help us. If we create our own Host for the Wep API we could create our own custom HttpControllerDispatcher and add or exception handler to that class, but that would be little tricky but is possible. We can in a Message Handler take a look at the HttpResponseMessage’s IsSuccessStatusCode property to see if the request has failed and if we throw the HttpResponseException in our ApiControllers, we could use the HttpResponseException and give it a Reason Phrase and use that to identify business exceptions or critical exceptions. I wouldn’t add an exception handler into a Message Handler, instead I should use the ExceptionFilterAttribute and register it globally for all ApiControllers. BUT, now to another interesting issue. What will happen if we have a Message Handler that throws an exception?  Those exceptions will not be catch and handled by the ExceptionFilterAttribute. I found a  bug in my previews blog post about “Log message Request and Response in ASP.NET WebAPI” in the MessageHandler I use to log incoming and outgoing messages. Here is the code from my blog before I fixed the bug:   public abstract class MessageHandler : DelegatingHandler { protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken) { var corrId = string.Format("{0}{1}", DateTime.Now.Ticks, Thread.CurrentThread.ManagedThreadId); var requestInfo = string.Format("{0} {1}", request.Method, request.RequestUri); var requestMessage = await request.Content.ReadAsByteArrayAsync(); await IncommingMessageAsync(corrId, requestInfo, requestMessage); var response = await base.SendAsync(request, cancellationToken); var responseMessage = await response.Content.ReadAsByteArrayAsync(); await OutgoingMessageAsync(corrId, requestInfo, responseMessage); return response; } protected abstract Task IncommingMessageAsync(string correlationId, string requestInfo, byte[] message); protected abstract Task OutgoingMessageAsync(string correlationId, string requestInfo, byte[] message); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   If a ApiController throws a HttpResponseException, the Content property of the HttpResponseMessage from the SendAsync will be NULL. So a null reference exception is thrown within the MessageHandler. The yellow screen of death will be returned to the client, and the content is HTML and the Http status code is 500. The bug in the MessageHandler was solved by adding a check against the HttpResponseMessage’s IsSuccessStatusCode property: public abstract class MessageHandler : DelegatingHandler { protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken) { var corrId = string.Format("{0}{1}", DateTime.Now.Ticks, Thread.CurrentThread.ManagedThreadId); var requestInfo = string.Format("{0} {1}", request.Method, request.RequestUri); var requestMessage = await request.Content.ReadAsByteArrayAsync(); await IncommingMessageAsync(corrId, requestInfo, requestMessage); var response = await base.SendAsync(request, cancellationToken); byte[] responseMessage; if (response.IsSuccessStatusCode) responseMessage = await response.Content.ReadAsByteArrayAsync(); else responseMessage = Encoding.UTF8.GetBytes(response.ReasonPhrase); await OutgoingMessageAsync(corrId, requestInfo, responseMessage); return response; } protected abstract Task IncommingMessageAsync(string correlationId, string requestInfo, byte[] message); protected abstract Task OutgoingMessageAsync(string correlationId, string requestInfo, byte[] message); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } If we don’t handle the exceptions that can occur in a custom Message Handler, we can have a hard time to find the problem causing the exception. The savior in this case is the Global.asax’s Application_Error: protected void Application_Error() { var exception = Server.GetLastError(); Debug.WriteLine(exception); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } I would recommend you to add the Application_Error to the Global.asax and log all exceptions to make sure all kind of exception is handled. Summary There are different ways we could add Exception Handling to the Wep API, we can use a custom ApiController, ExceptionFilterAttribute, IHttpActionInvoker or Message Handler. The ExceptionFilterAttribute would be a good place to add a global exception handling, require very few modification, just register it globally for all ApiControllers, even the IHttpActionInvoker can be used to minimize the modifications of files. Adding the Application_Error to the global.asax is a good way to catch all unhandled exception that can occur, for example exception thrown in a Message Handler.   If you want to know when I have posted a blog post, you can follow me on twitter @fredrikn

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• Metro: Declarative Data Binding

  - by Stephen.Walther

  The goal of this blog post is to describe how declarative data binding works in the WinJS library. In particular, you learn how to use both the data-win-bind and data-win-bindsource attributes. You also learn how to use calculated properties and converters to format the value of a property automatically when performing data binding. By taking advantage of WinJS data binding, you can use the Model-View-ViewModel (MVVM) pattern when building Metro style applications with JavaScript. By using the MVVM pattern, you can prevent your JavaScript code from spinning into chaos. The MVVM pattern provides you with a standard pattern for organizing your JavaScript code which results in a more maintainable application. Using Declarative Bindings You can use the data-win-bind attribute with any HTML element in a page. The data-win-bind attribute enables you to bind (associate) an attribute of an HTML element to the value of a property. Imagine, for example, that you want to create a product details page. You want to show a product object in a page. In that case, you can create the following HTML page to display the product details: <!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>Application1</title> <!-- WinJS references --> <link href="//Microsoft.WinJS.0.6/css/ui-dark.css" rel="stylesheet"> <script src="//Microsoft.WinJS.0.6/js/base.js"></script> <script src="//Microsoft.WinJS.0.6/js/ui.js"></script> <!-- Application1 references --> <link href="/css/default.css" rel="stylesheet"> <script src="/js/default.js"></script> </head> <body> <h1>Product Details</h1> <div class="field"> Product Name: <span data-win-bind="innerText:name"></span> </div> <div class="field"> Product Price: <span data-win-bind="innerText:price"></span> </div> <div class="field"> Product Picture: <br /> <img data-win-bind="src:photo;alt:name" /> </div> </body> </html> The HTML page above contains three data-win-bind attributes – one attribute for each product property displayed. You use the data-win-bind attribute to set properties of the HTML element associated with the data-win-attribute. The data-win-bind attribute takes a semicolon delimited list of element property names and data source property names: data-win-bind=”elementPropertyName:datasourcePropertyName; elementPropertyName:datasourcePropertyName;…” In the HTML page above, the first two data-win-bind attributes are used to set the values of the innerText property of the SPAN elements. The last data-win-bind attribute is used to set the values of the IMG element’s src and alt attributes. By the way, using data-win-bind attributes is perfectly valid HTML5. The HTML5 standard enables you to add custom attributes to an HTML document just as long as the custom attributes start with the prefix data-. So you can add custom attributes to an HTML5 document with names like data-stephen, data-funky, or data-rover-dog-is-hungry and your document will validate. The product object displayed in the page above with the data-win-bind attributes is created in the default.js file: (function () { "use strict"; var app = WinJS.Application; app.onactivated = function (eventObject) { if (eventObject.detail.kind === Windows.ApplicationModel.Activation.ActivationKind.launch) { var product = { name: "Tesla", price: 80000, photo: "/images/TeslaPhoto.png" }; WinJS.Binding.processAll(null, product); } }; app.start(); })(); In the code above, a product object is created with a name, price, and photo property. The WinJS.Binding.processAll() method is called to perform the actual binding (Don’t confuse WinJS.Binding.processAll() and WinJS.UI.processAll() – these are different methods). The first parameter passed to the processAll() method represents the root element for the binding. In other words, binding happens on this element and its child elements. If you provide the value null, then binding happens on the entire body of the document (document.body). The second parameter represents the data context. This is the object that has the properties which are displayed with the data-win-bind attributes. In the code above, the product object is passed as the data context parameter. Another word for data context is view model.  Creating Complex View Models In the previous section, we used the data-win-bind attribute to display the properties of a simple object: a single product. However, you can use binding with more complex view models including view models which represent multiple objects. For example, the view model in the following default.js file represents both a customer and a product object. Furthermore, the customer object has a nested address object: (function () { "use strict"; var app = WinJS.Application; app.onactivated = function (eventObject) { if (eventObject.detail.kind === Windows.ApplicationModel.Activation.ActivationKind.launch) { var viewModel = { customer: { firstName: "Fred", lastName: "Flintstone", address: { street: "1 Rocky Way", city: "Bedrock", country: "USA" } }, product: { name: "Bowling Ball", price: 34.55 } }; WinJS.Binding.processAll(null, viewModel); } }; app.start(); })(); The following page displays the customer (including the customer address) and the product. Notice that you can use dot notation to refer to child objects in a view model such as customer.address.street. <!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>Application1</title> <!-- WinJS references --> <link href="//Microsoft.WinJS.0.6/css/ui-dark.css" rel="stylesheet"> <script src="//Microsoft.WinJS.0.6/js/base.js"></script> <script src="//Microsoft.WinJS.0.6/js/ui.js"></script> <!-- Application1 references --> <link href="/css/default.css" rel="stylesheet"> <script src="/js/default.js"></script> </head> <body> <h1>Customer Details</h1> <div class="field"> First Name: <span data-win-bind="innerText:customer.firstName"></span> </div> <div class="field"> Last Name: <span data-win-bind="innerText:customer.lastName"></span> </div> <div class="field"> Address: <address> <span data-win-bind="innerText:customer.address.street"></span> <br /> <span data-win-bind="innerText:customer.address.city"></span> <br /> <span data-win-bind="innerText:customer.address.country"></span> </address> </div> <h1>Product</h1> <div class="field"> Name: <span data-win-bind="innerText:product.name"></span> </div> <div class="field"> Price: <span data-win-bind="innerText:product.price"></span> </div> </body> </html> A view model can be as complicated as you need and you can bind the view model to a view (an HTML document) by using declarative bindings. Creating Calculated Properties You might want to modify a property before displaying the property. For example, you might want to format the product price property before displaying the property. You don’t want to display the raw product price “80000”. Instead, you want to display the formatted price “$80,000”. You also might need to combine multiple properties. For example, you might need to display the customer full name by combining the values of the customer first and last name properties. In these situations, it is tempting to call a function when performing binding. For example, you could create a function named fullName() which concatenates the customer first and last name. Unfortunately, the WinJS library does not support the following syntax: <span data-win-bind=”innerText:fullName()”></span> Instead, in these situations, you should create a new property in your view model that has a getter. For example, the customer object in the following default.js file includes a property named fullName which combines the values of the firstName and lastName properties: (function () { "use strict"; var app = WinJS.Application; app.onactivated = function (eventObject) { if (eventObject.detail.kind === Windows.ApplicationModel.Activation.ActivationKind.launch) { var customer = { firstName: "Fred", lastName: "Flintstone", get fullName() { return this.firstName + " " + this.lastName; } }; WinJS.Binding.processAll(null, customer); } }; app.start(); })(); The customer object has a firstName, lastName, and fullName property. Notice that the fullName property is defined with a getter function. When you read the fullName property, the values of the firstName and lastName properties are concatenated and returned. The following HTML page displays the fullName property in an H1 element. You can use the fullName property in a data-win-bind attribute in exactly the same way as any other property. <!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>Application1</title> <!-- WinJS references --> <link href="//Microsoft.WinJS.0.6/css/ui-dark.css" rel="stylesheet"> <script src="//Microsoft.WinJS.0.6/js/base.js"></script> <script src="//Microsoft.WinJS.0.6/js/ui.js"></script> <!-- Application1 references --> <link href="/css/default.css" rel="stylesheet"> <script src="/js/default.js"></script> </head> <body> <h1 data-win-bind="innerText:fullName"></h1> <div class="field"> First Name: <span data-win-bind="innerText:firstName"></span> </div> <div class="field"> Last Name: <span data-win-bind="innerText:lastName"></span> </div> </body> </html> Creating a Converter In the previous section, you learned how to format the value of a property by creating a property with a getter. This approach makes sense when the formatting logic is specific to a particular view model. If, on the other hand, you need to perform the same type of formatting for multiple view models then it makes more sense to create a converter function. A converter function is a function which you can apply whenever you are using the data-win-bind attribute. Imagine, for example, that you want to create a general function for displaying dates. You always want to display dates using a short format such as 12/25/1988. The following JavaScript file – named converters.js – contains a shortDate() converter: (function (WinJS) { var shortDate = WinJS.Binding.converter(function (date) { return date.getMonth() + 1 + "/" + date.getDate() + "/" + date.getFullYear(); }); // Export shortDate WinJS.Namespace.define("MyApp.Converters", { shortDate: shortDate }); })(WinJS); The file above uses the Module Pattern, a pattern which is used through the WinJS library. To learn more about the Module Pattern, see my blog entry on namespaces and modules: http://stephenwalther.com/blog/archive/2012/02/22/windows-web-applications-namespaces-and-modules.aspx The file contains the definition for a converter function named shortDate(). This function converts a JavaScript date object into a short date string such as 12/1/1988. The converter function is created with the help of the WinJS.Binding.converter() method. This method takes a normal function and converts it into a converter function. Finally, the shortDate() converter is added to the MyApp.Converters namespace. You can call the shortDate() function by calling MyApp.Converters.shortDate(). The default.js file contains the customer object that we want to bind. Notice that the customer object has a firstName, lastName, and birthday property. We will use our new shortDate() converter when displaying the customer birthday property: (function () { "use strict"; var app = WinJS.Application; app.onactivated = function (eventObject) { if (eventObject.detail.kind === Windows.ApplicationModel.Activation.ActivationKind.launch) { var customer = { firstName: "Fred", lastName: "Flintstone", birthday: new Date("12/1/1988") }; WinJS.Binding.processAll(null, customer); } }; app.start(); })(); We actually use our shortDate converter in the HTML document. The following HTML document displays all of the customer properties: <!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>Application1</title> <!-- WinJS references --> <link href="//Microsoft.WinJS.0.6/css/ui-dark.css" rel="stylesheet"> <script src="//Microsoft.WinJS.0.6/js/base.js"></script> <script src="//Microsoft.WinJS.0.6/js/ui.js"></script> <!-- Application1 references --> <link href="/css/default.css" rel="stylesheet"> <script src="/js/default.js"></script> <script type="text/javascript" src="js/converters.js"></script> </head> <body> <h1>Customer Details</h1> <div class="field"> First Name: <span data-win-bind="innerText:firstName"></span> </div> <div class="field"> Last Name: <span data-win-bind="innerText:lastName"></span> </div> <div class="field"> Birthday: <span data-win-bind="innerText:birthday MyApp.Converters.shortDate"></span> </div> </body> </html> Notice the data-win-bind attribute used to display the birthday property. It looks like this: <span data-win-bind="innerText:birthday MyApp.Converters.shortDate"></span> The shortDate converter is applied to the birthday property when the birthday property is bound to the SPAN element’s innerText property. Using data-win-bindsource Normally, you pass the view model (the data context) which you want to use with the data-win-bind attributes in a page by passing the view model to the WinJS.Binding.processAll() method like this: WinJS.Binding.processAll(null, viewModel); As an alternative, you can specify the view model declaratively in your markup by using the data-win-datasource attribute. For example, the following default.js script exposes a view model with the fully-qualified name of MyWinWebApp.viewModel: (function () { "use strict"; var app = WinJS.Application; app.onactivated = function (eventObject) { if (eventObject.detail.kind === Windows.ApplicationModel.Activation.ActivationKind.launch) { // Create view model var viewModel = { customer: { firstName: "Fred", lastName: "Flintstone" }, product: { name: "Bowling Ball", price: 12.99 } }; // Export view model to be seen by universe WinJS.Namespace.define("MyWinWebApp", { viewModel: viewModel }); // Process data-win-bind attributes WinJS.Binding.processAll(); } }; app.start(); })(); In the code above, a view model which represents a customer and a product is exposed as MyWinWebApp.viewModel. The following HTML page illustrates how you can use the data-win-bindsource attribute to bind to this view model: <!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>Application1</title> <!-- WinJS references --> <link href="//Microsoft.WinJS.0.6/css/ui-dark.css" rel="stylesheet"> <script src="//Microsoft.WinJS.0.6/js/base.js"></script> <script src="//Microsoft.WinJS.0.6/js/ui.js"></script> <!-- Application1 references --> <link href="/css/default.css" rel="stylesheet"> <script src="/js/default.js"></script> </head> <body> <h1>Customer Details</h1> <div data-win-bindsource="MyWinWebApp.viewModel.customer"> <div class="field"> First Name: <span data-win-bind="innerText:firstName"></span> </div> <div class="field"> Last Name: <span data-win-bind="innerText:lastName"></span> </div> </div> <h1>Product</h1> <div data-win-bindsource="MyWinWebApp.viewModel.product"> <div class="field"> Name: <span data-win-bind="innerText:name"></span> </div> <div class="field"> Price: <span data-win-bind="innerText:price"></span> </div> </div> </body> </html> The data-win-bindsource attribute is used twice in the page above: it is used with the DIV element which contains the customer details and it is used with the DIV element which contains the product details. If an element has a data-win-bindsource attribute then all of the child elements of that element are affected. The data-win-bind attributes of all of the child elements are bound to the data source represented by the data-win-bindsource attribute. Summary The focus of this blog entry was data binding using the WinJS library. You learned how to use the data-win-bind attribute to bind the properties of an HTML element to a view model. We also discussed several advanced features of data binding. We examined how to create calculated properties by including a property with a getter in your view model. We also discussed how you can create a converter function to format the value of a view model property when binding the property. Finally, you learned how to use the data-win-bindsource attribute to specify a view model declaratively.

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• Why i disconnect every few seconds? using USB wireless adapter

  - by Rev3rse

  i know it's for ubuntu questions..but mint and ubuntu are very similiar and i had the same problem with linux ubuntu too..so i think this is the right place for my question anyway i don't have experience with drivers and other things,after installing Linux on my machine( i did dist-upgrade btw) everything seem to be great because i didn't have to install any driver, after a while i realized that my connection stop after few minutes(actually it shows that I'm connected but it's not) so i have to reconnect and after few minutes it disconnect again. I'm using Alfa USB wireless adapter AWS036H, and my Linux version is 11 i think the driver i'm using is Realtek i searched in the Internet and i found nothing. these are some outputs of few things people usually ask for: Note: I'm NOT using a laptop. dmsg: [19445.604448] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=2.174.220.77 DST=192.168.1.6 LEN=52 TOS=0x00 PREC=0x00 TTL=104 ID=10466 DF PROTO=TCP SPT=55150 DPT=6881 WINDOW=8192 RES=0x00 SYN URGP=0 [19448.164050] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=192.168.1.254 DST=192.168.1.6 LEN=56 TOS=0x00 PREC=0x00 TTL=255 ID=41982 PROTO=ICMP TYPE=3 CODE=0 [SRC=192.168.1.6 DST=91.189.88.33 LEN=52 TOS=0x00 PREC=0x00 TTL=63 ID=7566 DF PROTO=TCP INCOMPLETE [8 bytes] ] [19465.079565] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=80.128.216.31 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=113 ID=5100 DF PROTO=TCP SPT=50169 DPT=6881 WINDOW=8192 RES=0x00 SYN URGP=0 [19486.270328] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=90.130.13.122 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=109 ID=22207 PROTO=UDP SPT=6881 DPT=6881 LEN=28 [19497.480522] wlan0: deauthenticating from 00:24:c8:4b:46:e0 by local choice (reason=3) [19497.593276] cfg80211: All devices are disconnected, going to restore regulatory settings [19497.593282] cfg80211: Restoring regulatory settings [19497.593346] cfg80211: Calling CRDA to update world regulatory domain [19497.638740] cfg80211: Updating information on frequency 2412 MHz for a 20 MHz width channel with regulatory rule: [19497.638745] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [19497.638749] cfg80211: Updating information on frequency 2417 MHz for a 20 MHz width channel with regulatory rule: [19497.638753] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [19497.638756] cfg80211: Updating information on frequency 2422 MHz for a 20 MHz width channel with regulatory rule: [19497.638760] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [19497.638763] cfg80211: Updating information on frequency 2427 MHz for a 20 MHz width channel with regulatory rule: [19497.638766] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [19497.638770] cfg80211: Updating information on frequency 2432 MHz for a 20 MHz width channel with regulatory rule: [19497.638773] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [19497.638776] cfg80211: Updating information on frequency 2437 MHz for a 20 MHz width channel with regulatory rule: [19497.638780] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [19497.638783] cfg80211: Updating information on frequency 2442 MHz for a 20 MHz width channel with regulatory rule: [19497.638787] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [19497.638790] cfg80211: Updating information on frequency 2447 MHz for a 20 MHz width channel with regulatory rule: [19497.638794] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [19497.638797] cfg80211: Updating information on frequency 2452 MHz for a 20 MHz width channel with regulatory rule: [19497.638801] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [19497.638804] cfg80211: Updating information on frequency 2457 MHz for a 20 MHz width channel with regulatory rule: [19497.638807] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [19497.638811] cfg80211: Updating information on frequency 2462 MHz for a 20 MHz width channel with regulatory rule: [19497.638814] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [19497.638817] cfg80211: Updating information on frequency 2467 MHz for a 20 MHz width channel with regulatory rule: [19497.638821] cfg80211: 2457000 KHz - 2482000 KHz @ KHz), (300 mBi, 2000 mBm) [19497.638824] cfg80211: Updating information on frequency 2472 MHz for a 20 MHz width channel with regulatory rule: [19497.638828] cfg80211: 2457000 KHz - 2482000 KHz @ KHz), (300 mBi, 2000 mBm) [19497.638831] cfg80211: Updating information on frequency 2484 MHz for a 20 MHz width channel with regulatory rule: [19497.638835] cfg80211: 2474000 KHz - 2494000 KHz @ KHz), (300 mBi, 2000 mBm) [19497.638838] cfg80211: World regulatory domain updated: [19497.638841] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp) [19497.638845] cfg80211: (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm) [19497.638848] cfg80211: (2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm) [19497.638852] cfg80211: (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm) [19497.638855] cfg80211: (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm) [19497.638859] cfg80211: (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm) [19513.145150] wlan0: authenticate with 00:24:c8:4b:46:e0 (try 1) [19513.146910] wlan0: authenticated [19513.252775] wlan0: associate with 00:24:c8:4b:46:e0 (try 1) [19513.255149] wlan0: RX AssocResp from 00:24:c8:4b:46:e0 (capab=0x411 status=0 aid=2) [19513.255154] wlan0: associated [19515.675091] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=91.79.8.40 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x20 TTL=110 ID=42720 DF PROTO=TCP SPT=1945 DPT=6881 WINDOW=65535 RES=0x00 SYN URGP=0 [19525.684312] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=78.13.80.169 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=109 ID=49890 DF PROTO=TCP SPT=53401 DPT=6881 WINDOW=16384 RES=0x00 SYN URGP=0 [19551.856766] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=85.228.39.93 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=103 ID=1162 PROTO=UDP SPT=6881 DPT=6881 LEN=28 [19564.623005] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=90.202.21.238 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=114 ID=17881 PROTO=UDP SPT=6881 DPT=6881 LEN=28 [19584.855364] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=2.49.151.87 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=117 ID=31716 PROTO=UDP SPT=6881 DPT=6881 LEN=28 [19604.688647] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=109.225.124.155 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=112 ID=6656 PROTO=UDP SPT=6881 DPT=6881 LEN=28 [19626.362529] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=81.184.50.41 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=114 ID=23241 DF PROTO=TCP SPT=1416 DPT=6881 WINDOW=65535 RES=0x00 SYN URGP=0 [19645.040906] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=92.250.245.244 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=51 ID=0 DF PROTO=TCP SPT=50061 DPT=6881 WINDOW=16384 RES=0x00 SYN URGP=0 [19665.212659] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=87.183.3.18 DST=192.168.1.6 LEN=52 TOS=0x00 PREC=0x00 TTL=111 ID=1689 DF PROTO=TCP SPT=62817 DPT=6881 WINDOW=8192 RES=0x00 SYN URGP=0 [19685.036415] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=78.13.80.169 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=109 ID=50638 DF PROTO=TCP SPT=49624 DPT=6881 WINDOW=16384 RES=0x00 SYN URGP=0 [19705.487915] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=217.122.17.82 DST=192.168.1.6 LEN=56 TOS=0x00 PREC=0x00 TTL=112 ID=19070 DF PROTO=TCP SPT=54795 DPT=6881 WINDOW=8192 RES=0x00 SYN URGP=0 [19726.779185] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=80.88.116.239 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=109 ID=32168 DF PROTO=TCP SPT=57330 DPT=6881 WINDOW=8192 RES=0x00 SYN URGP=0 [19744.755673] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=109.124.5.43 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=113 ID=2288 DF PROTO=TCP SPT=6475 DPT=6881 WINDOW=65535 RES=0x00 SYN URGP=0 [19764.449183] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=79.216.35.19 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=113 ID=4281 PROTO=UDP SPT=6881 DPT=6881 LEN=28 [19784.456189] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=81.82.25.149 DST=192.168.1.6 LEN=52 TOS=0x00 PREC=0x00 TTL=114 ID=1866 DF PROTO=TCP SPT=59507 DPT=6881 WINDOW=8192 RES=0x00 SYN URGP=0 [19804.836687] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=81.56.199.3 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=108 ID=14749 PROTO=UDP SPT=6881 DPT=6881 LEN=28 [19824.812685] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=186.28.7.159 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=107 ID=44686 PROTO=UDP SPT=23418 DPT=6881 LEN=28 [19847.683314] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=78.13.80.169 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=108 ID=63046 DF PROTO=TCP SPT=52192 DPT=6881 WINDOW=16384 RES=0x00 SYN URGP=0 [19884.711455] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=84.146.24.238 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=113 ID=27914 PROTO=UDP SPT=6881 DPT=6881 LEN=28 [19884.983589] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=2.107.130.61 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=112 ID=7742 PROTO=UDP SPT=6881 DPT=6881 LEN=28 [19905.681078] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=95.21.11.121 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=114 ID=31775 PROTO=UDP SPT=6881 DPT=6881 LEN=28 [19926.035707] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=109.76.132.55 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=113 ID=28140 DF PROTO=TCP SPT=51905 DPT=6881 WINDOW=8192 RES=0x00 SYN URGP=0 [19945.668326] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=188.92.0.197 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=113 ID=7865 PROTO=UDP SPT=6881 DPT=6881 LEN=28 [19967.200339] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=83.252.102.172 DST=192.168.1.6 LEN=52 TOS=0x00 PREC=0x00 TTL=105 ID=28408 DF PROTO=TCP SPT=63505 DPT=6881 WINDOW=8192 RES=0x00 SYN URGP=0 [19999.752732] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=79.166.171.200 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=110 ID=36405 PROTO=UDP SPT=6881 DPT=6881 LEN=28 [20007.928719] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=79.235.59.16 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=112 ID=46415 DF PROTO=TCP SPT=4537 DPT=6881 WINDOW=16384 RES=0x00 SYN URGP=0 [20026.181726] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=81.182.169.36 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=106 ID=25126 PROTO=UDP SPT=6881 DPT=6881 LEN=28 [20048.845358] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=87.66.118.104 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=111 ID=18068 DF PROTO=TCP SPT=49928 DPT=6881 WINDOW=8192 RES=0x00 SYN URGP=0 [20064.341857] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=77.2.63.153 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=107 ID=7242 PROTO=UDP SPT=6881 DPT=6881 LEN=28 [20090.093490] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=93.16.17.210 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=108 ID=894 PROTO=UDP SPT=6881 DPT=6881 LEN=28 [20104.443995] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=89.83.235.99 DST=192.168.1.6 LEN=52 TOS=0x00 PREC=0x00 TTL=114 ID=17295 DF PROTO=TCP SPT=58979 DPT=6881 WINDOW=8192 RES=0x00 SYN URGP=0 [20128.625374] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=81.62.91.79 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=107 ID=21793 DF PROTO=TCP SPT=51446 DPT=6881 WINDOW=8192 RES=0x00 SYN URGP=0 [20151.055506] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=84.135.217.213 DST=192.168.1.6 LEN=52 TOS=0x00 PREC=0x00 TTL=112 ID=32452 DF PROTO=TCP SPT=55136 DPT=6881 WINDOW=8192 RES=0x00 SYN URGP=0 [20164.618874] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=91.79.8.40 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x20 TTL=110 ID=47784 DF PROTO=TCP SPT=2422 DPT=6881 WINDOW=65535 RES=0x00 SYN URGP=0 [20184.337745] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=83.252.212.71 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=107 ID=14544 PROTO=UDP SPT=6881 DPT=6881 LEN=28 [20205.007512] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=91.62.158.247 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=110 ID=21562 DF PROTO=TCP SPT=3933 DPT=6881 WINDOW=65535 RES=0x00 SYN URGP=0 [20225.204018] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=84.146.24.238 DST=192.168.1.6 LEN=52 TOS=0x00 PREC=0x00 TTL=113 ID=15045 DF PROTO=TCP SPT=49630 DPT=6881 WINDOW=8192 RES=0x00 SYN URGP=0 [20244.842290] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=82.82.190.168 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=112 ID=23741 DF PROTO=TCP SPT=50766 DPT=6881 WINDOW=8192 RES=0x00 SYN URGP=0 [20266.701649] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=88.153.108.124 DST=192.168.1.6 LEN=48 TOS=0x02 PREC=0x00 TTL=111 ID=206 DF PROTO=TCP SPT=2451 DPT=6881 WINDOW=65535 RES=0x00 SYN URGP=0 [20286.305414] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=78.240.86.73 DST=192.168.1.6 LEN=52 TOS=0x00 PREC=0x00 TTL=107 ID=325 DF PROTO=TCP SPT=65184 DPT=6881 WINDOW=8192 RES=0x00 SYN URGP=0 [20294.293989] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=192.168.1.254 DST=192.168.1.6 LEN=56 TOS=0x00 PREC=0x00 TTL=255 ID=43133 PROTO=ICMP TYPE=3 CODE=0 [SRC=192.168.1.6 DST=91.189.88.33 LEN=52 TOS=0x00 PREC=0x00 TTL=63 ID=56899 DF PROTO=TCP INCOMPLETE [8 bytes] ] [20294.297015] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=192.168.1.254 DST=192.168.1.6 LEN=56 TOS=0x00 PREC=0x00 TTL=255 ID=43134 PROTO=ICMP TYPE=3 CODE=0 [SRC=192.168.1.6 DST=91.189.88.40 LEN=52 TOS=0x00 PREC=0x00 TTL=63 ID=12080 DF PROTO=TCP INCOMPLETE [8 bytes] ] [20294.297242] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=192.168.1.254 DST=192.168.1.6 LEN=56 TOS=0x00 PREC=0x00 TTL=255 ID=43135 PROTO=ICMP TYPE=3 CODE=0 [SRC=192.168.1.6 DST=91.189.88.33 LEN=52 TOS=0x00 PREC=0x00 TTL=63 ID=25195 DF PROTO=TCP INCOMPLETE [8 bytes] ] [20295.478338] wlan0: deauthenticating from 00:24:c8:4b:46:e0 by local choice (reason=3) [20295.552735] cfg80211: All devices are disconnected, going to restore regulatory settings [20295.552742] cfg80211: Restoring regulatory settings [20295.552748] cfg80211: Calling CRDA to update world regulatory domain [20295.680635] cfg80211: Updating information on frequency 2412 MHz for a 20 MHz width channel with regulatory rule: [20295.680641] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [20295.680644] cfg80211: Updating information on frequency 2417 MHz for a 20 MHz width channel with regulatory rule: [20295.680648] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [20295.680652] cfg80211: Updating information on frequency 2422 MHz for a 20 MHz width channel with regulatory rule: [20295.680655] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [20295.680658] cfg80211: Updating information on frequency 2427 MHz for a 20 MHz width channel with regulatory rule: [20295.680662] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [20295.680665] cfg80211: Updating information on frequency 2432 MHz for a 20 MHz width channel with regulatory rule: [20295.680669] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [20295.680672] cfg80211: Updating information on frequency 2437 MHz for a 20 MHz width channel with regulatory rule: [20295.680676] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [20295.680679] cfg80211: Updating information on frequency 2442 MHz for a 20 MHz width channel with regulatory rule: [20295.680683] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [20295.680687] cfg80211: Updating information on frequency 2447 MHz for a 20 MHz width channel with regulatory rule: [20295.680690] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [20295.680693] cfg80211: Updating information on frequency 2452 MHz for a 20 MHz width channel with regulatory rule: [20295.680697] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [20295.680700] cfg80211: Updating information on frequency 2457 MHz for a 20 MHz width channel with regulatory rule: [20295.680704] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [20295.680708] cfg80211: Updating information on frequency 2462 MHz for a 20 MHz width channel with regulatory rule: [20295.680711] cfg80211: 2402000 KHz - 2472000 KHz @ KHz), (300 mBi, 2000 mBm) [20295.680715] cfg80211: Updating information on frequency 2467 MHz for a 20 MHz width channel with regulatory rule: [20295.680718] cfg80211: 2457000 KHz - 2482000 KHz @ KHz), (300 mBi, 2000 mBm) [20295.680722] cfg80211: Updating information on frequency 2472 MHz for a 20 MHz width channel with regulatory rule: [20295.680725] cfg80211: 2457000 KHz - 2482000 KHz @ KHz), (300 mBi, 2000 mBm) [20295.680728] cfg80211: Updating information on frequency 2484 MHz for a 20 MHz width channel with regulatory rule: [20295.680732] cfg80211: 2474000 KHz - 2494000 KHz @ KHz), (300 mBi, 2000 mBm) [20295.680736] cfg80211: World regulatory domain updated: [20295.680738] cfg80211: (start_freq - end_freq @ bandwidth), (max_antenna_gain, max_eirp) [20295.680742] cfg80211: (2402000 KHz - 2472000 KHz @ 40000 KHz), (300 mBi, 2000 mBm) [20295.680745] cfg80211: (2457000 KHz - 2482000 KHz @ 20000 KHz), (300 mBi, 2000 mBm) [20295.680749] cfg80211: (2474000 KHz - 2494000 KHz @ 20000 KHz), (300 mBi, 2000 mBm) [20295.680752] cfg80211: (5170000 KHz - 5250000 KHz @ 40000 KHz), (300 mBi, 2000 mBm) [20295.680756] cfg80211: (5735000 KHz - 5835000 KHz @ 40000 KHz), (300 mBi, 2000 mBm) [20306.009341] wlan0: authenticate with 00:24:c8:4b:46:e0 (try 1) [20306.011225] wlan0: authenticated [20306.118095] wlan0: associate with 00:24:c8:4b:46:e0 (try 1) [20306.120963] wlan0: RX AssocResp from 00:24:c8:4b:46:e0 (capab=0x411 status=0 aid=2) [20306.120967] wlan0: associated [20307.364427] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=87.91.101.130 DST=192.168.1.6 LEN=64 TOS=0x00 PREC=0x00 TTL=49 ID=36839 DF PROTO=TCP SPT=62492 DPT=6881 WINDOW=65535 RES=0x00 SYN URGP=0 [20310.914290] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=192.168.1.254 DST=192.168.1.6 LEN=56 TOS=0x00 PREC=0x00 TTL=255 ID=43180 PROTO=ICMP TYPE=3 CODE=0 [SRC=192.168.1.6 DST=91.189.88.33 LEN=52 TOS=0x00 PREC=0x00 TTL=63 ID=56900 DF PROTO=TCP INCOMPLETE [8 bytes] ] [20310.936634] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=192.168.1.254 DST=192.168.1.6 LEN=56 TOS=0x00 PREC=0x00 TTL=255 ID=43181 PROTO=ICMP TYPE=3 CODE=0 [SRC=192.168.1.6 DST=91.189.88.40 LEN=52 TOS=0x00 PREC=0x00 TTL=63 ID=12081 DF PROTO=TCP INCOMPLETE [8 bytes] ] [20310.939017] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=192.168.1.254 DST=192.168.1.6 LEN=56 TOS=0x00 PREC=0x00 TTL=255 ID=43182 PROTO=ICMP TYPE=3 CODE=0 [SRC=192.168.1.6 DST=91.189.88.33 LEN=52 TOS=0x00 PREC=0x00 TTL=63 ID=25196 DF PROTO=TCP INCOMPLETE [8 bytes] ] [20325.941050] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=217.118.78.99 DST=192.168.1.6 LEN=48 TOS=0x00 PREC=0x00 TTL=113 ID=4407 PROTO=UDP SPT=2970 DPT=6881 LEN=28 [20328.801724] [UFW BLOCK] IN=wlan0 OUT= MAC=00:c0:ca:44:62:d1:00:24:c8:4b:46:e0:08:00 SRC=192.168.1.254 DST=192.168.1.6 LEN=56 TOS=0x00 PREC=0x00 TTL=255 ID=43196 PROTO=ICMP TYPE=3 CODE=0 [SRC=192.168.1.6 DST=91.189.88.33 LEN=52 TOS=0x00 PREC=0x00 TTL=63 ID=56901 DF PROTO=TCP INCOMPLETE [8 bytes] ] ... inxi -N Network: Card-1 Realtek RTL8101E/RTL8102E PCI Express Fast Ethernet controller driver r8169 Card-2 Realtek RTL-8139/8139C/8139C+ driver 8139too /usr/lib/linuxmint/mintWifi/mintWifi.py ------------------------- * I. scanning WIFI PCI devices... ------------------------- * II. querying ndiswrapper... ------------------------- * III. querying iwconfig... lo no wireless extensions. eth0 no wireless extensions. eth1 no wireless extensions. wlan0 IEEE 802.11bg ESSID:"Home" Mode:Managed Frequency:2.437 GHz Access Point: 00:24:C8:4B:46:E0 Bit Rate=54 Mb/s Tx-Power=20 dBm Retry long limit:7 RTS thr:off Fragment thr:off Power Management:off Link Quality=68/70 Signal level=-42 dBm Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0 Tx excessive retries:0 Invalid misc:1132 Missed beacon:0 ------------------------- * IV. querying ifconfig... eth0 Link encap:Ethernet HWaddr 00:1f:d0:c9:b8:8e UP BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) Interrupt:43 Base address:0x4000 eth1 Link encap:Ethernet HWaddr 00:0e:2e:77:88:16 UP BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) Interrupt:19 Base address:0xd000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:10696 errors:0 dropped:0 overruns:0 frame:0 TX packets:10696 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:3823011 (3.8 MB) TX bytes:3823011 (3.8 MB) wlan0 Link encap:Ethernet HWaddr 00:c0:ca:44:62:d1 inet addr:192.168.1.6 Bcast:255.255.255.255 Mask:255.255.255.0 inet6 addr: fe80::2c0:caff:fe44:62d1/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:90424 errors:0 dropped:0 overruns:0 frame:0 TX packets:65201 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:98024465 (98.0 MB) TX bytes:10345450 (10.3 MB) ------------------------- * V. querying DHCP... lspci 00:00.0 Host bridge: Intel Corporation 82G33/G31/P35/P31 Express DRAM Controller (rev 10) 00:01.0 PCI bridge: Intel Corporation 82G33/G31/P35/P31 Express PCI Express Root Port (rev 10) 00:1b.0 Audio device: Intel Corporation N10/ICH 7 Family High Definition Audio Controller (rev 01) 00:1c.0 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 1 (rev 01) 00:1c.1 PCI bridge: Intel Corporation N10/ICH 7 Family PCI Express Port 2 (rev 01) 00:1d.0 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #1 (rev 01) 00:1d.1 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #2 (rev 01) 00:1d.2 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #3 (rev 01) 00:1d.3 USB Controller: Intel Corporation N10/ICH 7 Family USB UHCI Controller #4 (rev 01) 00:1d.7 USB Controller: Intel Corporation N10/ICH 7 Family USB2 EHCI Controller (rev 01) 00:1e.0 PCI bridge: Intel Corporation 82801 PCI Bridge (rev e1) 00:1f.0 ISA bridge: Intel Corporation 82801GB/GR (ICH7 Family) LPC Interface Bridge (rev 01) 00:1f.2 IDE interface: Intel Corporation N10/ICH7 Family SATA IDE Controller (rev 01) 00:1f.3 SMBus: Intel Corporation N10/ICH 7 Family SMBus Controller (rev 01) 01:00.0 VGA compatible controller: nVidia Corporation G96 [GeForce 9400 GT] (rev a1) 03:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8101E/RTL8102E PCI Express Fast Ethernet controller (rev 02) 04:01.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL-8139/8139C/8139C+ (rev 10) lsmod Module Size Used by ipt_REJECT 12512 1 ipt_LOG 12784 5 xt_limit 12541 7 xt_tcpudp 12531 8 ipt_addrtype 12535 4 xt_state 12514 7 ip6table_filter 12711 1 ip6_tables 22545 1 ip6table_filter nf_nat_irc 12542 0 nf_conntrack_irc 13138 1 nf_nat_irc nf_nat_ftp 12548 0 nf_nat 24827 2 nf_nat_irc,nf_nat_ftp nf_conntrack_ipv4 19024 9 nf_nat nf_defrag_ipv4 12649 1 nf_conntrack_ipv4 nf_conntrack_ftp 13106 1 nf_nat_ftp nf_conntrack 69744 7 xt_state,nf_nat_irc,nf_conntrack_irc,nf_nat_ftp,nf_nat,nf_conntrack_ipv4,nf_conntrack_ftp iptable_filter 12706 1 ip_tables 18125 1 iptable_filter x_tables 21907 10 ipt_REJECT,ipt_LOG,xt_limit,xt_tcpudp,ipt_addrtype,xt_state,ip6table_filter,ip6_tables,iptable_filter,ip_tables nls_utf8 12493 10 udf 83795 1 crc_itu_t 12627 1 udf usb_storage 43946 1 uas 17676 0 snd_seq_dummy 12686 0 cryptd 19801 0 aes_i586 16956 1 aes_generic 38023 1 aes_i586 binfmt_misc 13213 1 dm_crypt 22463 0 vesafb 13449 1 nvidia 9766978 44 arc4 12473 2 rtl8187 56206 0 mac80211 257001 1 rtl8187 cfg80211 156212 2 rtl8187,mac80211 ppdev 12849 0 snd_hda_codec_realtek 255882 1 parport_pc 32111 1 psmouse 73312 0 eeprom_93cx6 12653 1 rtl8187 snd_hda_intel 24113 5 snd_hda_codec 90901 2 snd_hda_codec_realtek,snd_hda_intel snd_hwdep 13274 1 snd_hda_codec snd_pcm 80042 3 snd_hda_intel,snd_hda_codec snd_seq_midi 13132 0 snd_rawmidi 25269 1 snd_seq_midi snd_seq_midi_event 14475 1 snd_seq_midi snd_seq 51291 3 snd_seq_dummy,snd_seq_midi,snd_seq_midi_event snd_timer 28659 2 snd_pcm,snd_seq snd_seq_device 14110 4 snd_seq_dummy,snd_seq_midi,snd_rawmidi,snd_seq joydev 17322 0 snd 55295 18 snd_hda_codec_realtek,snd_hda_intel,snd_hda_codec,snd_hwdep,snd_pcm,snd_rawmidi,snd_seq,snd_timer,snd_seq_device serio_raw 12990 0 soundcore 12600 1 snd snd_page_alloc 14073 2 snd_hda_intel,snd_pcm lp 13349 0 parport 36746 3 ppdev,parport_pc,lp usbhid 41704 0 hid 77084 1 usbhid dm_raid45 88410 0 xor 21860 1 dm_raid45 btrfs 527388 0 zlib_deflate 26594 1 btrfs libcrc32c 12543 1 btrfs 8139too 23208 0 8139cp 22497 0 r8169 42534 0 floppy 60032 0

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• Node.js Adventure - When Node Flying in Wind

  - by Shaun

  In the first post of this series I mentioned some popular modules in the community, such as underscore, async, etc.. I also listed a module named “Wind (zh-CN)”, which is created by one of my friend, Jeff Zhao (zh-CN). Now I would like to use a separated post to introduce this module since I feel it brings a new async programming style in not only Node.js but JavaScript world. If you know or heard about the new feature in C# 5.0 called “async and await”, or you learnt F#, you will find the “Wind” brings the similar async programming experience in JavaScript. By using “Wind”, we can write async code that looks like the sync code. The callbacks, async stats and exceptions will be handled by “Wind” automatically and transparently.   What’s the Problem: Dense “Callback” Phobia Let’s firstly back to my second post in this series. As I mentioned in that post, when we wanted to read some records from SQL Server we need to open the database connection, and then execute the query. In Node.js all IO operation are designed as async callback pattern which means when the operation was done, it will invoke a function which was taken from the last parameter. For example the database connection opening code would be like this. 1: sql.open(connectionString, function(error, conn) { 2: if(error) { 3: // some error handling code 4: } 5: else { 6: // connection opened successfully 7: } 8: }); And then if we need to query the database the code would be like this. It nested in the previous function. 1: sql.open(connectionString, function(error, conn) { 2: if(error) { 3: // some error handling code 4: } 5: else { 6: // connection opened successfully 7: conn.queryRaw(command, function(error, results) { 8: if(error) { 9: // failed to execute this command 10: } 11: else { 12: // records retrieved successfully 13: } 14: }; 15: } 16: }); Assuming if we need to copy some data from this database to another then we need to open another connection and execute the command within the function under the query function. 1: sql.open(connectionString, function(error, conn) { 2: if(error) { 3: // some error handling code 4: } 5: else { 6: // connection opened successfully 7: conn.queryRaw(command, function(error, results) { 8: if(error) { 9: // failed to execute this command 10: } 11: else { 12: // records retrieved successfully 13: target.open(targetConnectionString, function(error, t_conn) { 14: if(error) { 15: // connect failed 16: } 17: else { 18: t_conn.queryRaw(copy_command, function(error, results) { 19: if(error) { 20: // copy failed 21: } 22: else { 23: // and then, what do you want to do now... 24: } 25: }; 26: } 27: }; 28: } 29: }; 30: } 31: }); This is just an example. In the real project the logic would be more complicated. This means our application might be messed up and the business process will be fragged by many callback functions. I would like call this “Dense Callback Phobia”. This might be a challenge how to make code straightforward and easy to read, something like below. 1: try 2: { 3: // open source connection 4: var s_conn = sqlConnect(s_connectionString); 5: // retrieve data 6: var results = sqlExecuteCommand(s_conn, s_command); 7: 8: // open target connection 9: var t_conn = sqlConnect(t_connectionString); 10: // prepare the copy command 11: var t_command = getCopyCommand(results); 12: // execute the copy command 13: sqlExecuteCommand(s_conn, t_command); 14: } 15: catch (ex) 16: { 17: // error handling 18: }   What’s the Problem: Sync-styled Async Programming Similar as the previous problem, the callback-styled async programming model makes the upcoming operation as a part of the current operation, and mixed with the error handling code. So it’s very hard to understand what on earth this code will do. And since Node.js utilizes non-blocking IO mode, we cannot invoke those operations one by one, as they will be executed concurrently. For example, in this post when I tried to copy the records from Windows Azure SQL Database (a.k.a. WASD) to Windows Azure Table Storage, if I just insert the data into table storage one by one and then print the “Finished” message, I will see the message shown before the data had been copied. This is because all operations were executed at the same time. In order to make the copy operation and print operation executed synchronously I introduced a module named “async” and the code was changed as below. 1: async.forEach(results.rows, 2: function (row, callback) { 3: var resource = { 4: "PartitionKey": row[1], 5: "RowKey": row[0], 6: "Value": row[2] 7: }; 8: client.insertEntity(tableName, resource, function (error) { 9: if (error) { 10: callback(error); 11: } 12: else { 13: console.log("entity inserted."); 14: callback(null); 15: } 16: }); 17: }, 18: function (error) { 19: if (error) { 20: error["target"] = "insertEntity"; 21: res.send(500, error); 22: } 23: else { 24: console.log("all done."); 25: res.send(200, "Done!"); 26: } 27: }); It ensured that the “Finished” message will be printed when all table entities had been inserted. But it cannot promise that the records will be inserted in sequence. It might be another challenge to make the code looks like in sync-style? 1: try 2: { 3: forEach(row in rows) { 4: var entity = { /* ... */ }; 5: tableClient.insert(tableName, entity); 6: } 7:  8: console.log("Finished"); 9: } 10: catch (ex) { 11: console.log(ex); 12: }   How “Wind” Helps “Wind” is a JavaScript library which provides the control flow with plain JavaScript for asynchronous programming (and more) without additional pre-compiling steps. It’s available in NPM so that we can install it through “npm install wind”. Now let’s create a very simple Node.js application as the example. This application will take some website URLs from the command arguments and tried to retrieve the body length and print them in console. Then at the end print “Finish”. I’m going to use “request” module to make the HTTP call simple so I also need to install by the command “npm install request”. The code would be like this. 1: var request = require("request"); 2:  3: // get the urls from arguments, the first two arguments are `node.exe` and `fetch.js` 4: var args = process.argv.splice(2); 5:  6: // main function 7: var main = function() { 8: for(var i = 0; i < args.length; i++) { 9: // get the url 10: var url = args[i]; 11: // send the http request and try to get the response and body 12: request(url, function(error, response, body) { 13: if(!error && response.statusCode == 200) { 14: // log the url and the body length 15: console.log( 16: "%s: %d.", 17: response.request.uri.href, 18: body.length); 19: } 20: else { 21: // log error 22: console.log(error); 23: } 24: }); 25: } 26: 27: // finished 28: console.log("Finished"); 29: }; 30:  31: // execute the main function 32: main(); Let’s execute this application. (I made them in multi-lines for better reading.) 1: node fetch.js 2: "http://www.igt.com/us-en.aspx" 3: "http://www.igt.com/us-en/games.aspx" 4: "http://www.igt.com/us-en/cabinets.aspx" 5: "http://www.igt.com/us-en/systems.aspx" 6: "http://www.igt.com/us-en/interactive.aspx" 7: "http://www.igt.com/us-en/social-gaming.aspx" 8: "http://www.igt.com/support.aspx" Below is the output. As you can see the finish message was printed at the beginning, and the pages’ length retrieved in a different order than we specified. This is because in this code the request command, console logging command are executed asynchronously and concurrently. Now let’s introduce “Wind” to make them executed in order, which means it will request the websites one by one, and print the message at the end.   First of all we need to import the “Wind” package and make sure the there’s only one global variant named “Wind”, and ensure it’s “Wind” instead of “wind”. 1: var Wind = require("wind");   Next, we need to tell “Wind” which code will be executed asynchronously so that “Wind” can control the execution process. In this case the “request” operation executed asynchronously so we will create a “Task” by using a build-in helps function in “Wind” named Wind.Async.Task.create. 1: var requestBodyLengthAsync = function(url) { 2: return Wind.Async.Task.create(function(t) { 3: request(url, function(error, response, body) { 4: if(error || response.statusCode != 200) { 5: t.complete("failure", error); 6: } 7: else { 8: var data = 9: { 10: uri: response.request.uri.href, 11: length: body.length 12: }; 13: t.complete("success", data); 14: } 15: }); 16: }); 17: }; The code above created a “Task” from the original request calling code. In “Wind” a “Task” means an operation will be finished in some time in the future. A “Task” can be started by invoke its start() method, but no one knows when it actually will be finished. The Wind.Async.Task.create helped us to create a task. The only parameter is a function where we can put the actual operation in, and then notify the task object it’s finished successfully or failed by using the complete() method. In the code above I invoked the request method. If it retrieved the response successfully I set the status of this task as “success” with the URL and body length. If it failed I set this task as “failure” and pass the error out.   Next, we will change the main() function. In “Wind” if we want a function can be controlled by Wind we need to mark it as “async”. This should be done by using the code below. 1: var main = eval(Wind.compile("async", function() { 2: })); When the application is running, Wind will detect “eval(Wind.compile(“async”, function” and generate an anonymous code from the body of this original function. Then the application will run the anonymous code instead of the original one. In our example the main function will be like this. 1: var main = eval(Wind.compile("async", function() { 2: for(var i = 0; i < args.length; i++) { 3: try 4: { 5: var result = $await(requestBodyLengthAsync(args[i])); 6: console.log( 7: "%s: %d.", 8: result.uri, 9: result.length); 10: } 11: catch (ex) { 12: console.log(ex); 13: } 14: } 15: 16: console.log("Finished"); 17: })); As you can see, when I tried to request the URL I use a new command named “$await”. It tells Wind, the operation next to $await will be executed asynchronously, and the main thread should be paused until it finished (or failed). So in this case, my application will be pause when the first response was received, and then print its body length, then try the next one. At the end, print the finish message.   Finally, execute the main function. The full code would be like this. 1: var request = require("request"); 2: var Wind = require("wind"); 3:  4: var args = process.argv.splice(2); 5:  6: var requestBodyLengthAsync = function(url) { 7: return Wind.Async.Task.create(function(t) { 8: request(url, function(error, response, body) { 9: if(error || response.statusCode != 200) { 10: t.complete("failure", error); 11: } 12: else { 13: var data = 14: { 15: uri: response.request.uri.href, 16: length: body.length 17: }; 18: t.complete("success", data); 19: } 20: }); 21: }); 22: }; 23:  24: var main = eval(Wind.compile("async", function() { 25: for(var i = 0; i < args.length; i++) { 26: try 27: { 28: var result = $await(requestBodyLengthAsync(args[i])); 29: console.log( 30: "%s: %d.", 31: result.uri, 32: result.length); 33: } 34: catch (ex) { 35: console.log(ex); 36: } 37: } 38: 39: console.log("Finished"); 40: })); 41:  42: main().start();   Run our new application. At the beginning we will see the compiled and generated code by Wind. Then we can see the pages were requested one by one, and at the end the finish message was printed. Below is the code Wind generated for us. As you can see the original code, the output code were shown. 1: // Original: 2: function () { 3: for(var i = 0; i < args.length; i++) { 4: try 5: { 6: var result = $await(requestBodyLengthAsync(args[i])); 7: console.log( 8: "%s: %d.", 9: result.uri, 10: result.length); 11: } 12: catch (ex) { 13: console.log(ex); 14: } 15: } 16: 17: console.log("Finished"); 18: } 19:  20: // Compiled: 21: /* async << function () { */ (function () { 22: var _builder_$0 = Wind.builders["async"]; 23: return _builder_$0.Start(this, 24: _builder_$0.Combine( 25: _builder_$0.Delay(function () { 26: /* var i = 0; */ var i = 0; 27: /* for ( */ return _builder_$0.For(function () { 28: /* ; i < args.length */ return i < args.length; 29: }, function () { 30: /* ; i ++) { */ i ++; 31: }, 32: /* try { */ _builder_$0.Try( 33: _builder_$0.Delay(function () { 34: /* var result = $await(requestBodyLengthAsync(args[i])); */ return _builder_$0.Bind(requestBodyLengthAsync(args[i]), function (result) { 35: /* console.log("%s: %d.", result.uri, result.length); */ console.log("%s: %d.", result.uri, result.length); 36: return _builder_$0.Normal(); 37: }); 38: }), 39: /* } catch (ex) { */ function (ex) { 40: /* console.log(ex); */ console.log(ex); 41: return _builder_$0.Normal(); 42: /* } */ }, 43: null 44: ) 45: /* } */ ); 46: }), 47: _builder_$0.Delay(function () { 48: /* console.log("Finished"); */ console.log("Finished"); 49: return _builder_$0.Normal(); 50: }) 51: ) 52: ); 53: /* } */ })   How Wind Works Someone may raise a big concern when you find I utilized “eval” in my code. Someone may assume that Wind utilizes “eval” to execute some code dynamically while “eval” is very low performance. But I would say, Wind does NOT use “eval” to run the code. It only use “eval” as a flag to know which code should be compiled at runtime. When the code was firstly been executed, Wind will check and find “eval(Wind.compile(“async”, function”. So that it knows this function should be compiled. Then it utilized parse-js to analyze the inner JavaScript and generated the anonymous code in memory. Then it rewrite the original code so that when the application was running it will use the anonymous one instead of the original one. Since the code generation was done at the beginning of the application was started, in the future no matter how long our application runs and how many times the async function was invoked, it will use the generated code, no need to generate again. So there’s no significant performance hurt when using Wind.   Wind in My Previous Demo Let’s adopt Wind into one of my previous demonstration and to see how it helps us to make our code simple, straightforward and easy to read and understand. In this post when I implemented the functionality that copied the records from my WASD to table storage, the logic would be like this. 1, Open database connection. 2, Execute a query to select all records from the table. 3, Recreate the table in Windows Azure table storage. 4, Create entities from each of the records retrieved previously, and then insert them into table storage. 5, Finally, show message as the HTTP response. But as the image below, since there are so many callbacks and async operations, it’s very hard to understand my logic from the code. Now let’s use Wind to rewrite our code. First of all, of course, we need the Wind package. Then we need to include the package files into project and mark them as “Copy always”. Add the Wind package into the source code. Pay attention to the variant name, you must use “Wind” instead of “wind”. 1: var express = require("express"); 2: var async = require("async"); 3: var sql = require("node-sqlserver"); 4: var azure = require("azure"); 5: var Wind = require("wind"); Now we need to create some async functions by using Wind. All async functions should be wrapped so that it can be controlled by Wind which are open database, retrieve records, recreate table (delete and create) and insert entity in table. Below are these new functions. All of them are created by using Wind.Async.Task.create. 1: sql.openAsync = function (connectionString) { 2: return Wind.Async.Task.create(function (t) { 3: sql.open(connectionString, function (error, conn) { 4: if (error) { 5: t.complete("failure", error); 6: } 7: else { 8: t.complete("success", conn); 9: } 10: }); 11: }); 12: }; 13:  14: sql.queryAsync = function (conn, query) { 15: return Wind.Async.Task.create(function (t) { 16: conn.queryRaw(query, function (error, results) { 17: if (error) { 18: t.complete("failure", error); 19: } 20: else { 21: t.complete("success", results); 22: } 23: }); 24: }); 25: }; 26:  27: azure.recreateTableAsync = function (tableName) { 28: return Wind.Async.Task.create(function (t) { 29: client.deleteTable(tableName, function (error, successful, response) { 30: console.log("delete table finished"); 31: client.createTableIfNotExists(tableName, function (error, successful, response) { 32: console.log("create table finished"); 33: if (error) { 34: t.complete("failure", error); 35: } 36: else { 37: t.complete("success", null); 38: } 39: }); 40: }); 41: }); 42: }; 43:  44: azure.insertEntityAsync = function (tableName, entity) { 45: return Wind.Async.Task.create(function (t) { 46: client.insertEntity(tableName, entity, function (error, entity, response) { 47: if (error) { 48: t.complete("failure", error); 49: } 50: else { 51: t.complete("success", null); 52: } 53: }); 54: }); 55: }; Then in order to use these functions we will create a new function which contains all steps for data copying. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: } 4: catch (ex) { 5: console.log(ex); 6: res.send(500, "Internal error."); 7: } 8: })); Let’s execute steps one by one with the “$await” keyword introduced by Wind so that it will be invoked in sequence. First is to open the database connection. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: } 7: catch (ex) { 8: console.log(ex); 9: res.send(500, "Internal error."); 10: } 11: })); Then retrieve all records from the database connection. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: // retrieve all records from database 7: var results = $await(sql.queryAsync(conn, "SELECT * FROM [Resource]")); 8: console.log("records selected. count = %d", results.rows.length); 9: } 10: catch (ex) { 11: console.log(ex); 12: res.send(500, "Internal error."); 13: } 14: })); After recreated the table, we need to create the entities and insert them into table storage. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: // retrieve all records from database 7: var results = $await(sql.queryAsync(conn, "SELECT * FROM [Resource]")); 8: console.log("records selected. count = %d", results.rows.length); 9: if (results.rows.length > 0) { 10: // recreate the table 11: $await(azure.recreateTableAsync(tableName)); 12: console.log("table created"); 13: // insert records in table storage one by one 14: for (var i = 0; i < results.rows.length; i++) { 15: var entity = { 16: "PartitionKey": results.rows[i][1], 17: "RowKey": results.rows[i][0], 18: "Value": results.rows[i][2] 19: }; 20: $await(azure.insertEntityAsync(tableName, entity)); 21: console.log("entity inserted"); 22: } 23: } 24: } 25: catch (ex) { 26: console.log(ex); 27: res.send(500, "Internal error."); 28: } 29: })); Finally, send response back to the browser. 1: var copyRecords = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: // retrieve all records from database 7: var results = $await(sql.queryAsync(conn, "SELECT * FROM [Resource]")); 8: console.log("records selected. count = %d", results.rows.length); 9: if (results.rows.length > 0) { 10: // recreate the table 11: $await(azure.recreateTableAsync(tableName)); 12: console.log("table created"); 13: // insert records in table storage one by one 14: for (var i = 0; i < results.rows.length; i++) { 15: var entity = { 16: "PartitionKey": results.rows[i][1], 17: "RowKey": results.rows[i][0], 18: "Value": results.rows[i][2] 19: }; 20: $await(azure.insertEntityAsync(tableName, entity)); 21: console.log("entity inserted"); 22: } 23: // send response 24: console.log("all done"); 25: res.send(200, "All done!"); 26: } 27: } 28: catch (ex) { 29: console.log(ex); 30: res.send(500, "Internal error."); 31: } 32: })); If we compared with the previous code we will find now it became more readable and much easy to understand. It’s very easy to know what this function does even though without any comments. When user go to URL “/was/copyRecords” we will execute the function above. The code would be like this. 1: app.get("/was/copyRecords", function (req, res) { 2: copyRecords(req, res).start(); 3: }); And below is the logs printed in local compute emulator console. As we can see the functions executed one by one and then finally the response back to me browser.   Scaffold Functions in Wind Wind provides not only the async flow control and compile functions, but many scaffold methods as well. We can build our async code more easily by using them. I’m going to introduce some basic scaffold functions here. In the code above I created some functions which wrapped from the original async function such as open database, create table, etc.. All of them are very similar, created a task by using Wind.Async.Task.create, return error or result object through Task.complete function. In fact, Wind provides some functions for us to create task object from the original async functions. If the original async function only has a callback parameter, we can use Wind.Async.Binding.fromCallback method to get the task object directly. For example the code below returned the task object which wrapped the file exist check function. 1: var Wind = require("wind"); 2: var fs = require("fs"); 3:  4: fs.existsAsync = Wind.Async.Binding.fromCallback(fs.exists); In Node.js a very popular async function pattern is that, the first parameter in the callback function represent the error object, and the other parameters is the return values. In this case we can use another build-in function in Wind named Wind.Async.Binding.fromStandard. For example, the open database function can be created from the code below. 1: sql.openAsync = Wind.Async.Binding.fromStandard(sql.open); 2:  3: /* 4: sql.openAsync = function (connectionString) { 5: return Wind.Async.Task.create(function (t) { 6: sql.open(connectionString, function (error, conn) { 7: if (error) { 8: t.complete("failure", error); 9: } 10: else { 11: t.complete("success", conn); 12: } 13: }); 14: }); 15: }; 16: */ When I was testing the scaffold functions under Wind.Async.Binding I found for some functions, such as the Azure SDK insert entity function, cannot be processed correctly. So I personally suggest writing the wrapped method manually.   Another scaffold method in Wind is the parallel tasks coordination. In this example, the steps of open database, retrieve records and recreated table should be invoked one by one, but it can be executed in parallel when copying data from database to table storage. In Wind there’s a scaffold function named Task.whenAll which can be used here. Task.whenAll accepts a list of tasks and creates a new task. It will be returned only when all tasks had been completed, or any errors occurred. For example in the code below I used the Task.whenAll to make all copy operation executed at the same time. 1: var copyRecordsInParallel = eval(Wind.compile("async", function (req, res) { 2: try { 3: // connect to the windows azure sql database 4: var conn = $await(sql.openAsync(connectionString)); 5: console.log("connection opened"); 6: // retrieve all records from database 7: var results = $await(sql.queryAsync(conn, "SELECT * FROM [Resource]")); 8: console.log("records selected. count = %d", results.rows.length); 9: if (results.rows.length > 0) { 10: // recreate the table 11: $await(azure.recreateTableAsync(tableName)); 12: console.log("table created"); 13: // insert records in table storage in parallal 14: var tasks = new Array(results.rows.length); 15: for (var i = 0; i < results.rows.length; i++) { 16: var entity = { 17: "PartitionKey": results.rows[i][1], 18: "RowKey": results.rows[i][0], 19: "Value": results.rows[i][2] 20: }; 21: tasks[i] = azure.insertEntityAsync(tableName, entity); 22: } 23: $await(Wind.Async.Task.whenAll(tasks)); 24: // send response 25: console.log("all done"); 26: res.send(200, "All done!"); 27: } 28: } 29: catch (ex) { 30: console.log(ex); 31: res.send(500, "Internal error."); 32: } 33: })); 34:  35: app.get("/was/copyRecordsInParallel", function (req, res) { 36: copyRecordsInParallel(req, res).start(); 37: });   Besides the task creation and coordination, Wind supports the cancellation solution so that we can send the cancellation signal to the tasks. It also includes exception solution which means any exceptions will be reported to the caller function.   Summary In this post I introduced a Node.js module named Wind, which created by my friend Jeff Zhao. As you can see, different from other async library and framework, adopted the idea from F# and C#, Wind utilizes runtime code generation technology to make it more easily to write async, callback-based functions in a sync-style way. By using Wind there will be almost no callback, and the code will be very easy to understand. Currently Wind is still under developed and improved. There might be some problems but the author, Jeff, should be very happy and enthusiastic to learn your problems, feedback, suggestion and comments. You can contact Jeff by - Email: [email protected] - Group: https://groups.google.com/d/forum/windjs - GitHub: https://github.com/JeffreyZhao/wind/issues   Source code can be download here.   Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

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• New features of C# 4.0

  This article covers New features of C# 4.0. Article has been divided into below sections. Introduction. Dynamic Lookup. Named and Optional Arguments. Features for COM interop. Variance. Relationship with Visual Basic. Resources. Other interested readings… 22 New Features of Visual Studio 2008 for .NET Professionals 50 New Features of SQL Server 2008 IIS 7.0 New features Introduction It is now close to a year since Microsoft Visual C# 3.0 shipped as part of Visual Studio 2008. In the VS Managed Languages team we are hard at work on creating the next version of the language (with the unsurprising working title of C# 4.0), and this document is a first public description of the planned language features as we currently see them. Please be advised that all this is in early stages of production and is subject to change. Part of the reason for sharing our plans in public so early is precisely to get the kind of feedback that will cause us to improve the final product before it rolls out. Simultaneously with the publication of this whitepaper, a first public CTP (community technology preview) of Visual Studio 2010 is going out as a Virtual PC image for everyone to try. Please use it to play and experiment with the features, and let us know of any thoughts you have. We ask for your understanding and patience working with very early bits, where especially new or newly implemented features do not have the quality or stability of a final product. The aim of the CTP is not to give you a productive work environment but to give you the best possible impression of what we are working on for the next release. The CTP contains a number of walkthroughs, some of which highlight the new language features of C# 4.0. Those are excellent for getting a hands-on guided tour through the details of some common scenarios for the features. You may consider this whitepaper a companion document to these walkthroughs, complementing them with a focus on the overall language features and how they work, as opposed to the specifics of the concrete scenarios. C# 4.0 The major theme for C# 4.0 is dynamic programming. Increasingly, objects are “dynamic” in the sense that their structure and behavior is not captured by a static type, or at least not one that the compiler knows about when compiling your program. Some examples include a. objects from dynamic programming languages, such as Python or Ruby b. COM objects accessed through IDispatch c. ordinary .NET types accessed through reflection d. objects with changing structure, such as HTML DOM objects While C# remains a statically typed language, we aim to vastly improve the interaction with such objects. A secondary theme is co-evolution with Visual Basic. Going forward we will aim to maintain the individual character of each language, but at the same time important new features should be introduced in both languages at the same time. They should be differentiated more by style and feel than by feature set. The new features in C# 4.0 fall into four groups: Dynamic lookup Dynamic lookup allows you to write method, operator and indexer calls, property and field accesses, and even object invocations which bypass the C# static type checking and instead gets resolved at runtime. Named and optional parameters Parameters in C# can now be specified as optional by providing a default value for them in a member declaration. When the member is invoked, optional arguments can be omitted. Furthermore, any argument can be passed by parameter name instead of position. COM specific interop features Dynamic lookup as well as named and optional parameters both help making programming against COM less painful than today. On top of that, however, we are adding a number of other small features that further improve the interop experience. Variance It used to be that an IEnumerable<string> wasn’t an IEnumerable<object>. Now it is – C# embraces type safe “co-and contravariance” and common BCL types are updated to take advantage of that. Dynamic Lookup Dynamic lookup allows you a unified approach to invoking things dynamically. With dynamic lookup, when you have an object in your hand you do not need to worry about whether it comes from COM, IronPython, the HTML DOM or reflection; you just apply operations to it and leave it to the runtime to figure out what exactly those operations mean for that particular object. This affords you enormous flexibility, and can greatly simplify your code, but it does come with a significant drawback: Static typing is not maintained for these operations. A dynamic object is assumed at compile time to support any operation, and only at runtime will you get an error if it wasn’t so. Oftentimes this will be no loss, because the object wouldn’t have a static type anyway, in other cases it is a tradeoff between brevity and safety. In order to facilitate this tradeoff, it is a design goal of C# to allow you to opt in or opt out of dynamic behavior on every single call. The dynamic type C# 4.0 introduces a new static type called dynamic. When you have an object of type dynamic you can “do things to it” that are resolved only at runtime: dynamic d = GetDynamicObject(…); d.M(7); The C# compiler allows you to call a method with any name and any arguments on d because it is of type dynamic. At runtime the actual object that d refers to will be examined to determine what it means to “call M with an int” on it. The type dynamic can be thought of as a special version of the type object, which signals that the object can be used dynamically. It is easy to opt in or out of dynamic behavior: any object can be implicitly converted to dynamic, “suspending belief” until runtime. Conversely, there is an “assignment conversion” from dynamic to any other type, which allows implicit conversion in assignment-like constructs: dynamic d = 7; // implicit conversion int i = d; // assignment conversion Dynamic operations Not only method calls, but also field and property accesses, indexer and operator calls and even delegate invocations can be dispatched dynamically: dynamic d = GetDynamicObject(…); d.M(7); // calling methods d.f = d.P; // getting and settings fields and properties d[“one”] = d[“two”]; // getting and setting thorugh indexers int i = d + 3; // calling operators string s = d(5,7); // invoking as a delegate The role of the C# compiler here is simply to package up the necessary information about “what is being done to d”, so that the runtime can pick it up and determine what the exact meaning of it is given an actual object d. Think of it as deferring part of the compiler’s job to runtime. The result of any dynamic operation is itself of type dynamic. Runtime lookup At runtime a dynamic operation is dispatched according to the nature of its target object d: COM objects If d is a COM object, the operation is dispatched dynamically through COM IDispatch. This allows calling to COM types that don’t have a Primary Interop Assembly (PIA), and relying on COM features that don’t have a counterpart in C#, such as indexed properties and default properties. Dynamic objects If d implements the interface IDynamicObject d itself is asked to perform the operation. Thus by implementing IDynamicObject a type can completely redefine the meaning of dynamic operations. This is used intensively by dynamic languages such as IronPython and IronRuby to implement their own dynamic object models. It will also be used by APIs, e.g. by the HTML DOM to allow direct access to the object’s properties using property syntax. Plain objects Otherwise d is a standard .NET object, and the operation will be dispatched using reflection on its type and a C# “runtime binder” which implements C#’s lookup and overload resolution semantics at runtime. This is essentially a part of the C# compiler running as a runtime component to “finish the work” on dynamic operations that was deferred by the static compiler. Example Assume the following code: dynamic d1 = new Foo(); dynamic d2 = new Bar(); string s; d1.M(s, d2, 3, null); Because the receiver of the call to M is dynamic, the C# compiler does not try to resolve the meaning of the call. Instead it stashes away information for the runtime about the call. This information (often referred to as the “payload”) is essentially equivalent to: “Perform an instance method call of M with the following arguments: 1. a string 2. a dynamic 3. a literal int 3 4. a literal object null” At runtime, assume that the actual type Foo of d1 is not a COM type and does not implement IDynamicObject. In this case the C# runtime binder picks up to finish the overload resolution job based on runtime type information, proceeding as follows: 1. Reflection is used to obtain the actual runtime types of the two objects, d1 and d2, that did not have a static type (or rather had the static type dynamic). The result is Foo for d1 and Bar for d2. 2. Method lookup and overload resolution is performed on the type Foo with the call M(string,Bar,3,null) using ordinary C# semantics. 3. If the method is found it is invoked; otherwise a runtime exception is thrown. Overload resolution with dynamic arguments Even if the receiver of a method call is of a static type, overload resolution can still happen at runtime. This can happen if one or more of the arguments have the type dynamic: Foo foo = new Foo(); dynamic d = new Bar(); var result = foo.M(d); The C# runtime binder will choose between the statically known overloads of M on Foo, based on the runtime type of d, namely Bar. The result is again of type dynamic. The Dynamic Language Runtime An important component in the underlying implementation of dynamic lookup is the Dynamic Language Runtime (DLR), which is a new API in .NET 4.0. The DLR provides most of the infrastructure behind not only C# dynamic lookup but also the implementation of several dynamic programming languages on .NET, such as IronPython and IronRuby. Through this common infrastructure a high degree of interoperability is ensured, but just as importantly the DLR provides excellent caching mechanisms which serve to greatly enhance the efficiency of runtime dispatch. To the user of dynamic lookup in C#, the DLR is invisible except for the improved efficiency. However, if you want to implement your own dynamically dispatched objects, the IDynamicObject interface allows you to interoperate with the DLR and plug in your own behavior. This is a rather advanced task, which requires you to understand a good deal more about the inner workings of the DLR. For API writers, however, it can definitely be worth the trouble in order to vastly improve the usability of e.g. a library representing an inherently dynamic domain. Open issues There are a few limitations and things that might work differently than you would expect. · The DLR allows objects to be created from objects that represent classes. However, the current implementation of C# doesn’t have syntax to support this. · Dynamic lookup will not be able to find extension methods. Whether extension methods apply or not depends on the static context of the call (i.e. which using clauses occur), and this context information is not currently kept as part of the payload. · Anonymous functions (i.e. lambda expressions) cannot appear as arguments to a dynamic method call. The compiler cannot bind (i.e. “understand”) an anonymous function without knowing what type it is converted to. One consequence of these limitations is that you cannot easily use LINQ queries over dynamic objects: dynamic collection = …; var result = collection.Select(e => e + 5); If the Select method is an extension method, dynamic lookup will not find it. Even if it is an instance method, the above does not compile, because a lambda expression cannot be passed as an argument to a dynamic operation. There are no plans to address these limitations in C# 4.0. Named and Optional Arguments Named and optional parameters are really two distinct features, but are often useful together. Optional parameters allow you to omit arguments to member invocations, whereas named arguments is a way to provide an argument using the name of the corresponding parameter instead of relying on its position in the parameter list. Some APIs, most notably COM interfaces such as the Office automation APIs, are written specifically with named and optional parameters in mind. Up until now it has been very painful to call into these APIs from C#, with sometimes as many as thirty arguments having to be explicitly passed, most of which have reasonable default values and could be omitted. Even in APIs for .NET however you sometimes find yourself compelled to write many overloads of a method with different combinations of parameters, in order to provide maximum usability to the callers. Optional parameters are a useful alternative for these situations. Optional parameters A parameter is declared optional simply by providing a default value for it: public void M(int x, int y = 5, int z = 7); Here y and z are optional parameters and can be omitted in calls: M(1, 2, 3); // ordinary call of M M(1, 2); // omitting z – equivalent to M(1, 2, 7) M(1); // omitting both y and z – equivalent to M(1, 5, 7) Named and optional arguments C# 4.0 does not permit you to omit arguments between commas as in M(1,,3). This could lead to highly unreadable comma-counting code. Instead any argument can be passed by name. Thus if you want to omit only y from a call of M you can write: M(1, z: 3); // passing z by name or M(x: 1, z: 3); // passing both x and z by name or even M(z: 3, x: 1); // reversing the order of arguments All forms are equivalent, except that arguments are always evaluated in the order they appear, so in the last example the 3 is evaluated before the 1. Optional and named arguments can be used not only with methods but also with indexers and constructors. Overload resolution Named and optional arguments affect overload resolution, but the changes are relatively simple: A signature is applicable if all its parameters are either optional or have exactly one corresponding argument (by name or position) in the call which is convertible to the parameter type. Betterness rules on conversions are only applied for arguments that are explicitly given – omitted optional arguments are ignored for betterness purposes. If two signatures are equally good, one that does not omit optional parameters is preferred. M(string s, int i = 1); M(object o); M(int i, string s = “Hello”); M(int i); M(5); Given these overloads, we can see the working of the rules above. M(string,int) is not applicable because 5 doesn’t convert to string. M(int,string) is applicable because its second parameter is optional, and so, obviously are M(object) and M(int). M(int,string) and M(int) are both better than M(object) because the conversion from 5 to int is better than the conversion from 5 to object. Finally M(int) is better than M(int,string) because no optional arguments are omitted. Thus the method that gets called is M(int). Features for COM interop Dynamic lookup as well as named and optional parameters greatly improve the experience of interoperating with COM APIs such as the Office Automation APIs. In order to remove even more of the speed bumps, a couple of small COM-specific features are also added to C# 4.0. Dynamic import Many COM methods accept and return variant types, which are represented in the PIAs as object. In the vast majority of cases, a programmer calling these methods already knows the static type of a returned object from context, but explicitly has to perform a cast on the returned value to make use of that knowledge. These casts are so common that they constitute a major nuisance. In order to facilitate a smoother experience, you can now choose to import these COM APIs in such a way that variants are instead represented using the type dynamic. In other words, from your point of view, COM signatures now have occurrences of dynamic instead of object in them. This means that you can easily access members directly off a returned object, or you can assign it to a strongly typed local variable without having to cast. To illustrate, you can now say excel.Cells[1, 1].Value = "Hello"; instead of ((Excel.Range)excel.Cells[1, 1]).Value2 = "Hello"; and Excel.Range range = excel.Cells[1, 1]; instead of Excel.Range range = (Excel.Range)excel.Cells[1, 1]; Compiling without PIAs Primary Interop Assemblies are large .NET assemblies generated from COM interfaces to facilitate strongly typed interoperability. They provide great support at design time, where your experience of the interop is as good as if the types where really defined in .NET. However, at runtime these large assemblies can easily bloat your program, and also cause versioning issues because they are distributed independently of your application. The no-PIA feature allows you to continue to use PIAs at design time without having them around at runtime. Instead, the C# compiler will bake the small part of the PIA that a program actually uses directly into its assembly. At runtime the PIA does not have to be loaded. Omitting ref Because of a different programming model, many COM APIs contain a lot of reference parameters. Contrary to refs in C#, these are typically not meant to mutate a passed-in argument for the subsequent benefit of the caller, but are simply another way of passing value parameters. It therefore seems unreasonable that a C# programmer should have to create temporary variables for all such ref parameters and pass these by reference. Instead, specifically for COM methods, the C# compiler will allow you to pass arguments by value to such a method, and will automatically generate temporary variables to hold the passed-in values, subsequently discarding these when the call returns. In this way the caller sees value semantics, and will not experience any side effects, but the called method still gets a reference. Open issues A few COM interface features still are not surfaced in C#. Most notably these include indexed properties and default properties. As mentioned above these will be respected if you access COM dynamically, but statically typed C# code will still not recognize them. There are currently no plans to address these remaining speed bumps in C# 4.0. Variance An aspect of generics that often comes across as surprising is that the following is illegal: IList<string> strings = new List<string>(); IList<object> objects = strings; The second assignment is disallowed because strings does not have the same element type as objects. There is a perfectly good reason for this. If it were allowed you could write: objects[0] = 5; string s = strings[0]; Allowing an int to be inserted into a list of strings and subsequently extracted as a string. This would be a breach of type safety. However, there are certain interfaces where the above cannot occur, notably where there is no way to insert an object into the collection. Such an interface is IEnumerable<T>. If instead you say: IEnumerable<object> objects = strings; There is no way we can put the wrong kind of thing into strings through objects, because objects doesn’t have a method that takes an element in. Variance is about allowing assignments such as this in cases where it is safe. The result is that a lot of situations that were previously surprising now just work. Covariance In .NET 4.0 the IEnumerable<T> interface will be declared in the following way: public interface IEnumerable<out T> : IEnumerable { IEnumerator<T> GetEnumerator(); } public interface IEnumerator<out T> : IEnumerator { bool MoveNext(); T Current { get; } } The “out” in these declarations signifies that the T can only occur in output position in the interface – the compiler will complain otherwise. In return for this restriction, the interface becomes “covariant” in T, which means that an IEnumerable<A> is considered an IEnumerable<B> if A has a reference conversion to B. As a result, any sequence of strings is also e.g. a sequence of objects. This is useful e.g. in many LINQ methods. Using the declarations above: var result = strings.Union(objects); // succeeds with an IEnumerable<object> This would previously have been disallowed, and you would have had to to some cumbersome wrapping to get the two sequences to have the same element type. Contravariance Type parameters can also have an “in” modifier, restricting them to occur only in input positions. An example is IComparer<T>: public interface IComparer<in T> { public int Compare(T left, T right); } The somewhat baffling result is that an IComparer<object> can in fact be considered an IComparer<string>! It makes sense when you think about it: If a comparer can compare any two objects, it can certainly also compare two strings. This property is referred to as contravariance. A generic type can have both in and out modifiers on its type parameters, as is the case with the Func<…> delegate types: public delegate TResult Func<in TArg, out TResult>(TArg arg); Obviously the argument only ever comes in, and the result only ever comes out. Therefore a Func<object,string> can in fact be used as a Func<string,object>. Limitations Variant type parameters can only be declared on interfaces and delegate types, due to a restriction in the CLR. Variance only applies when there is a reference conversion between the type arguments. For instance, an IEnumerable<int> is not an IEnumerable<object> because the conversion from int to object is a boxing conversion, not a reference conversion. Also please note that the CTP does not contain the new versions of the .NET types mentioned above. In order to experiment with variance you have to declare your own variant interfaces and delegate types. COM Example Here is a larger Office automation example that shows many of the new C# features in action. using System; using System.Diagnostics; using System.Linq; using Excel = Microsoft.Office.Interop.Excel; using Word = Microsoft.Office.Interop.Word; class Program { static void Main(string[] args) { var excel = new Excel.Application(); excel.Visible = true; excel.Workbooks.Add(); // optional arguments omitted excel.Cells[1, 1].Value = "Process Name"; // no casts; Value dynamically excel.Cells[1, 2].Value = "Memory Usage"; // accessed var processes = Process.GetProcesses() .OrderByDescending(p =&gt; p.WorkingSet) .Take(10); int i = 2; foreach (var p in processes) { excel.Cells[i, 1].Value = p.ProcessName; // no casts excel.Cells[i, 2].Value = p.WorkingSet; // no casts i++; } Excel.Range range = excel.Cells[1, 1]; // no casts Excel.Chart chart = excel.ActiveWorkbook.Charts. Add(After: excel.ActiveSheet); // named and optional arguments chart.ChartWizard( Source: range.CurrentRegion, Title: "Memory Usage in " + Environment.MachineName); //named+optional chart.ChartStyle = 45; chart.CopyPicture(Excel.XlPictureAppearance.xlScreen, Excel.XlCopyPictureFormat.xlBitmap, Excel.XlPictureAppearance.xlScreen); var word = new Word.Application(); word.Visible = true; word.Documents.Add(); // optional arguments word.Selection.Paste(); } } The code is much more terse and readable than the C# 3.0 counterpart. Note especially how the Value property is accessed dynamically. This is actually an indexed property, i.e. a property that takes an argument; something which C# does not understand. However the argument is optional. Since the access is dynamic, it goes through the runtime COM binder which knows to substitute the default value and call the indexed property. Thus, dynamic COM allows you to avoid accesses to the puzzling Value2 property of Excel ranges. Relationship with Visual Basic A number of the features introduced to C# 4.0 already exist or will be introduced in some form or other in Visual Basic: · Late binding in VB is similar in many ways to dynamic lookup in C#, and can be expected to make more use of the DLR in the future, leading to further parity with C#. · Named and optional arguments have been part of Visual Basic for a long time, and the C# version of the feature is explicitly engineered with maximal VB interoperability in mind. · NoPIA and variance are both being introduced to VB and C# at the same time. VB in turn is adding a number of features that have hitherto been a mainstay of C#. As a result future versions of C# and VB will have much better feature parity, for the benefit of everyone. Resources All available resources concerning C# 4.0 can be accessed through the C# Dev Center. Specifically, this white paper and other resources can be found at the Code Gallery site. Enjoy! span.fullpost {display:none;}

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• Deploy ASP.NET Web Applications with Web Deployment Projects

  - by Ben Griswold

  One may quickly build and deploy an ASP.NET web application via the Publish option in Visual Studio.  This option works great for most simple deployment scenarios but it won’t always cut it.  Let’s say you need to automate your deployments. Or you have environment-specific configuration settings. Or you need to execute pre/post build operations when you do your builds.  If so, you should consider using Web Deployment Projects. The Web Deployment Project type doesn’t come out-of-the-box with Visual Studio 2008.  You’ll need to Download Visual Studio® 2008 Web Deployment Projects – RTW and install if you want to follow along with this tutorial. I’ve created a shiny new ASP.NET MVC project.  Web Deployment Projects work with websites, web applications and MVC projects so feel free to go with any web project type you’d like.  Once your web application is in place, it’s time to add the Web Deployment project.  You can hunt and peck around the File > New > New Project… dialogue as long as you’d like, but you aren’t going to find what you need.  Instead, select the web project and then choose the “Add Web Deployment Project…” hiding behind the Build menu option. I prefer to name my projects based on the environment in which I plan to deploy.  In this case, I’ll be rolling to the QA machine. Don’t expect too much to happen at this point.  A seemingly empty project with a funny icon will be added to your solution.  That’s it. I want to take a minute and talk about configuration settings before we continue.  Some of the common settings which might change from environment to environment are appSettings, connectionStrings and mailSettings.  Here’s a look at my updated web.config: <appSettings>   <add key="MvcApplication293.Url" value="http://localhost:50596/" />     </appSettings> <connectionStrings>   <add name="ApplicationServices"        connectionString="data source=.\SQLEXPRESS;Integrated Security=SSPI;AttachDBFilename=|DataDirectory|aspnetdb.mdf;User Instance=true"        providerName="System.Data.SqlClient"/> </connectionStrings>   <system.net>   <mailSettings>     <smtp from="[email protected]">         <network host="server.com" userName="username" password="password" port="587" defaultCredentials="false"/>     </smtp>   </mailSettings> </system.net> I want to update these values prior to deploying to the QA environment.  There are variations to this approach, but I like to maintain environment-specific settings for each of the web.config sections in the Config/[Environment] project folders.  I’ve provided a screenshot of the QA environment settings below. It may be obvious what one should include in each of the three files.  Basically, it is a copy of the associated web.config section with updated setting values.  For example, the AppSettings.config file may include a reference to the QA web url, the DB.config would include the QA database server and login information and the StmpSettings.config would include a QA Stmp server and user information. <?xml version="1.0" encoding="utf-8" ?> <appSettings>   <add key="MvcApplication293.Url" value="http://qa.MvcApplicatinon293.com/" /> </appSettings> AppSettings.config  <?xml version="1.0" encoding="utf-8" ?> <connectionStrings>   <add name="ApplicationServices"        connectionString="server=QAServer;integrated security=SSPI;database=MvcApplication293"        providerName="System.Data.SqlClient"/>   </connectionStrings> Db.config  <?xml version="1.0" encoding="utf-8" ?> <smtp from="[email protected]">     <network host="qaserver.com" userName="qausername" password="qapassword" port="587" defaultCredentials="false"/> </smtp> SmtpSettings.config  I think our web project is ready to deploy.  Now, it’s time to concentrate on the Web Deployment Project itself.  Right-click on the project file and open the Property Pages. The first thing to call out is the Configuration dropdown.  I only deploy a project which is built in Release Mode so I only setup the Web Deployment Project for this mode.  (This is when you change the Configuration selection to “Release.”)  I typically keep the Output Folder default value – .\Release\.  When the application is built, all artifacts will be dropped in the .\Release\ folder relative to the Web Deployment Project root.  The final option may be up for some debate.  I like to roll out updatable websites so I select the “Allow this precompiled site to be updatable” option.  I really do like to follow standard SDLC processes when I release my software but there are those times when you just have to make a hotfix to production and I like to keep this option open if need be.  If you are strongly opposed to this idea, please, by all means, don’t check the box. The next tab is boring.  I don’t like to deploy a crazy number of DLLs so I merge all outputs to a single assembly.  Again, you may have another option and feel free to change this selection if you so wish. If you follow my lead, take care when choosing a single assembly name.  The Assembly Name can not be the same as the website or any other project in your solution otherwise you’ll receive a circular reference build error.  In other words, I can’t name the assembly MvcApplication293 or my output window would start yelling at me. Remember when we called out our QA configuration files?  Click on the Deployment tab and you’ll see how where going to use them.  Notice the Web.config file section replacements value.  All this does is swap called out web.config sections with the content of the Config\QA\* files.  You can reduce or extend this list as you deem fit.  Did you see the “Use external configuration source file” option?  You know how you can point any of your web.config sections to an external file via the configSource attribute?  This option allows you to leverage that technique and instead of replacing the content of the sections, you will replace the configSource attribute value instead. <appSettings configSource="Config\QA\AppSettings.config" /> Go ahead and Apply your changes.  I’d like to take a look at the project file we just updated.  Right-click on the Web Deployment Project and select “Open Project File.” One of the first configuration blocks reflects core Release build settings.  There are a couple of points I’d like to call out here: DebugSymbols=false ensures the compilation debug attribute in your web.config is flipped to false as part of build process.  There’s some crumby (more likely old) documentation which implies you need a ToggleDebugCompilation task to make this happen.  Nope. Just make sure the DebugSymbols is set to false.  EnableUpdateable implies a single dll for the web application rather than a dll for each object and and empty view file. I think updatable applications are cleaner and include the benefit (or risk based on your perspective) that portions of the application can be updated directly on the server.  I called this out earlier but I wanted to reiterate. <PropertyGroup Condition=" '$(Configuration)|$(Platform)' == 'Release|AnyCPU' ">     <DebugSymbols>false</DebugSymbols>     <OutputPath>.\Release</OutputPath>     <EnableUpdateable>true</EnableUpdateable>     <UseMerge>true</UseMerge>     <SingleAssemblyName>MvcApplication293</SingleAssemblyName>     <DeleteAppCodeCompiledFiles>true</DeleteAppCodeCompiledFiles>     <UseWebConfigReplacement>true</UseWebConfigReplacement>     <ValidateWebConfigReplacement>true</ValidateWebConfigReplacement>     <DeleteAppDataFolder>true</DeleteAppDataFolder>   </PropertyGroup> The next section is self-explanatory.  The content merely reflects the replacement value you provided via the Property Pages. <ItemGroup Condition="'$(Configuration)|$(Platform)' == 'Release|AnyCPU'">     <WebConfigReplacementFiles Include="Config\QA\AppSettings.config">       <Section>appSettings</Section>     </WebConfigReplacementFiles>     <WebConfigReplacementFiles Include="Config\QA\Db.config">       <Section>connectionStrings</Section>     </WebConfigReplacementFiles>     <WebConfigReplacementFiles Include="Config\QA\SmtpSettings.config">       <Section>system.net/mailSettings/smtp</Section>     </WebConfigReplacementFiles>   </ItemGroup> You’ll want to extend the ItemGroup section to include the files you wish to exclude from the build.  The sample ExcludeFromBuild nodes exclude all obj, svn, csproj, user, pdb artifacts from the build. Enough though they files aren’t included in your web project, you’ll need to exclude them or they’ll show up along with required deployment artifacts.  <ItemGroup Condition="'$(Configuration)|$(Platform)' == 'Release|AnyCPU'">     <WebConfigReplacementFiles Include="Config\QA\AppSettings.config">       <Section>appSettings</Section>     </WebConfigReplacementFiles>     <WebConfigReplacementFiles Include="Config\QA\Db.config">       <Section>connectionStrings</Section>     </WebConfigReplacementFiles>     <WebConfigReplacementFiles Include="Config\QA\SmtpSettings.config">       <Section>system.net/mailSettings/smtp</Section>     </WebConfigReplacementFiles>     <ExcludeFromBuild Include="$(SourceWebPhysicalPath)\obj\**\*.*" />     <ExcludeFromBuild Include="$(SourceWebPhysicalPath)\**\.svn\**\*.*" />     <ExcludeFromBuild Include="$(SourceWebPhysicalPath)\**\.svn\**\*" />     <ExcludeFromBuild Include="$(SourceWebPhysicalPath)\**\*.csproj" />     <ExcludeFromBuild Include="$(SourceWebPhysicalPath)\**\*.user" />     <ExcludeFromBuild Include="$(SourceWebPhysicalPath)\bin\*.pdb" />     <ExcludeFromBuild Include="$(SourceWebPhysicalPath)\Notes.txt" />   </ItemGroup> Pre/post build and Pre/post merge tasks are added to the final code block.  By default, your project file should look like the following – a completely commented out section. <!– To modify your build process, add your task inside one of        the targets below and uncomment it. Other similar extension        points exist, see Microsoft.WebDeployment.targets.   <Target Name="BeforeBuild">   </Target>   <Target Name="BeforeMerge">   </Target>   <Target Name="AfterMerge">   </Target>   <Target Name="AfterBuild">   </Target>   –> Update the section to remove all temporary Config folders and files after the build.  <!– To modify your build process, add your task inside one of        the targets below and uncomment it. Other similar extension        points exist, see Microsoft.WebDeployment.targets.     <Target Name="BeforeMerge">   </Target>   <Target Name="AfterMerge">   </Target>     <Target Name="BeforeBuild">      </Target>       –>   <Target Name="AfterBuild">     <!– WebConfigReplacement requires the Config files. Remove after build. –>     <RemoveDir Directories="$(OutputPath)\Config" />   </Target> That’s it for setup.  Save the project file, flip the solution to Release Mode and build.  If there’s an issue, consult the Output window for details.  If all went well, you will find your deployment artifacts in your Web Deployment Project folder like so. Both the code source and published application will be there. Inside the Release folder you will find your “published files” and you’ll notice the Config folder is no where to be found.  In the Source folder, all project files are found with the exception of the items which were excluded from the build. I’ll wrap up this tutorial by calling out a little Web Deployment pet peeve of mine: there doesn’t appear to be a way to add an existing web deployment project to a solution.  The best I can come up with is create a new web deployment project and then copy and paste the contents of the existing project file into the new project file.  It’s not a big deal but it bugs me. Download the Solution

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• jQuery Time Entry with Time Navigation Keys

  - by Rick Strahl

  So, how do you display time values in your Web applications? Displaying date AND time values in applications is lot less standardized than date display only. While date input has become fairly universal with various date picker controls available, time entry continues to be a bit of a non-standardized. In my own applications I tend to use the jQuery UI DatePicker control for date entries and it works well for that. Here's an example: The date entry portion is well defined and it makes perfect sense to have a calendar pop up so you can pick a date from a rich UI when necessary. However, time values are much less obvious when it comes to displaying a UI or even just making time entries more useful. There are a slew of time picker controls available but other than adding some visual glitz, they are not really making time entry any easier. Part of the reason for this is that time entry is usually pretty simple. Clicking on a dropdown of any sort and selecting a value from a long scrolling list tends to take more user interaction than just typing 5 characters (7 if am/pm is used). Keystrokes can make Time Entry easier Time entry maybe pretty simple, but I find that adding a few hotkeys to handle date navigation can make it much easier. Specifically it'd be nice to have keys to: Jump to the current time (Now) Increase/decrease minutes Increase/decrease hours The timeKeys jQuery PlugIn Some time ago I created a small plugin to handle this scenario. It's non-visual other than tooltip that pops up when you press ? to display the hotkeys that are available: Try it Online The keys loosely follow the ancient Quicken convention of using the first and last letters of what you're increasing decreasing (ie. H to decrease, R to increase hours and + and - for the base unit or minutes here). All navigation happens via the keystrokes shown above, so it's all non-visual, which I think is the most efficient way to deal with dates. To hook up the plug-in, start with the textbox:<input type="text" id="txtTime" name="txtTime" value="12:05 pm" title="press ? for time options" /> Note the title which might be useful to alert people using the field that additional functionality is available. To hook up the plugin code is as simple as:$("#txtTime").timeKeys(); You essentially tie the plugin to any text box control. OptionsThe syntax for timeKeys allows for an options map parameter:$(selector).timeKeys(options); Options are passed as a parameter map object which can have the following properties: timeFormatYou can pass in a format string that allows you to format the date. The default is "hh:mm t" which is US time format that shows a 12 hour clock with am/pm. Alternately you can pass in "HH:mm" which uses 24 hour time. HH, hh, mm and t are translated in the format string - you can arrange the format as you see fit. callbackYou can also specify a callback function that is called when the date value has been set. This allows you to either re-format the date or perform post processing (such as displaying highlight if it's after a certain hour for example). Here's another example that uses both options:$("#txtTime").timeKeys({ timeFormat: "HH:mm", callback: function (time) { showStatus("new time is: " + time.toString() + " " + $(this).val() ); } }); The plugin code itself is fairly simple. It hooks the keydown event and checks for the various keys that affect time navigation which is straight forward. The bulk of the code however deals with parsing the time value and formatting the output using a Time class that implements parsing, formatting and time navigation methods. Here's the code for the timeKeys jQuery plug-in:/// <reference path="jquery.js" /> /// <reference path="ww.jquery.js" /> (function ($) { $.fn.timeKeys = function (options) { /// <summary> /// Attaches a set of hotkeys to time fields /// + Add minute - subtract minute /// H Subtract Hour R Add houR /// ? Show keys /// </summary> /// <param name="options" type="object"> /// Options: /// timeFormat: "hh:mm t" by default HH:mm alternate /// callback: callback handler after time assignment /// </param> /// <example> /// var proxy = new ServiceProxy("JsonStockService.svc/"); /// proxy.invoke("GetStockQuote",{symbol:"msft"},function(quote) { alert(result.LastPrice); },onPageError); ///</example> if (this.length < 1) return this; var opt = { timeFormat: "hh:mm t", callback: null } $.extend(opt, options); return this.keydown(function (e) { var $el = $(this); var time = new Time($el.val()); //alert($(this).val() + " " + time.toString() + " " + time.date.toString()); switch (e.keyCode) { case 78: // [N]ow time = new Time(new Date()); break; case 109: case 189: // - time.addMinutes(-1); break; case 107: case 187: // + time.addMinutes(1); break; case 72: //H time.addHours(-1); break; case 82: //R time.addHours(1); break; case 191: // ? if (e.shiftKey) $(this).tooltip("<b>N</b> Now<br/><b>+</b> add minute<br /><b>-</b> subtract minute<br /><b>H</b> Subtract Hour<br /><b>R</b> add hour", 4000, { isHtml: true }); return false; default: return true; } $el.val(time.toString(opt.timeFormat)); if (opt.callback) { // call async and set context in this element setTimeout(function () { opt.callback.call($el.get(0), time) }, 1); } return false; }); } Time = function (time, format) { /// <summary> /// Time object that can parse and format /// a time values. /// </summary> /// <param name="time" type="object"> /// A time value as a string (12:15pm or 23:01), a Date object /// or time value. /// /// </param> /// <param name="format" type="string"> /// Time format string: /// HH:mm (23:01) /// hh:mm t (11:01 pm) /// </param> /// <example> /// var time = new Time( new Date()); /// time.addHours(5); /// time.addMinutes(10); /// var s = time.toString(); /// /// var time2 = new Time(s); // parse with constructor /// var t = time2.parse("10:15 pm"); // parse with .parse() method /// alert( t.hours + " " + t.mins + " " + t.ampm + " " + t.hours25) ///</example> var _I = this; this.date = new Date(); this.timeFormat = "hh:mm t"; if (format) this.timeFormat = format; this.parse = function (time) { /// <summary> /// Parses time value from a Date object, or string in format of: /// 12:12pm or 23:01 /// </summary> /// <param name="time" type="any"> /// A time value as a string (12:15pm or 23:01), a Date object /// or time value. /// /// </param> if (!time) return null; // Date if (time.getDate) { var t = {}; var d = time; t.hours24 = d.getHours(); t.mins = d.getMinutes(); t.ampm = "am"; if (t.hours24 > 11) { t.ampm = "pm"; if (t.hours24 > 12) t.hours = t.hours24 - 12; } time = t; } if (typeof (time) == "string") { var parts = time.split(":"); if (parts < 2) return null; var time = {}; time.hours = parts[0] * 1; time.hours24 = time.hours; time.mins = parts[1].toLowerCase(); if (time.mins.indexOf("am") > -1) { time.ampm = "am"; time.mins = time.mins.replace("am", ""); if (time.hours == 12) time.hours24 = 0; } else if (time.mins.indexOf("pm") > -1) { time.ampm = "pm"; time.mins = time.mins.replace("pm", ""); if (time.hours < 12) time.hours24 = time.hours + 12; } time.mins = time.mins * 1; } _I.date.setMinutes(time.mins); _I.date.setHours(time.hours24); return time; }; this.addMinutes = function (mins) { /// <summary> /// adds minutes to the internally stored time value. /// </summary> /// <param name="mins" type="number"> /// number of minutes to add to the date /// </param> _I.date.setMinutes(_I.date.getMinutes() + mins); } this.addHours = function (hours) { /// <summary> /// adds hours the internally stored time value. /// </summary> /// <param name="hours" type="number"> /// number of hours to add to the date /// </param> _I.date.setHours(_I.date.getHours() + hours); } this.getTime = function () { /// <summary> /// returns a time structure from the currently /// stored time value. /// Properties: hours, hours24, mins, ampm /// </summary> return new Time(new Date()); h } this.toString = function (format) { /// <summary> /// returns a short time string for the internal date /// formats: 12:12 pm or 23:12 /// </summary> /// <param name="format" type="string"> /// optional format string for date /// HH:mm, hh:mm t /// </param> if (!format) format = _I.timeFormat; var hours = _I.date.getHours(); if (format.indexOf("t") > -1) { if (hours > 11) format = format.replace("t", "pm") else format = format.replace("t", "am") } if (format.indexOf("HH") > -1) format = format.replace("HH", hours.toString().padL(2, "0")); if (format.indexOf("hh") > -1) { if (hours > 12) hours -= 12; if (hours == 0) hours = 12; format = format.replace("hh", hours.toString().padL(2, "0")); } if (format.indexOf("mm") > -1) format = format.replace("mm", _I.date.getMinutes().toString().padL(2, "0")); return format; } // construction if (time) this.time = this.parse(time); } String.prototype.padL = function (width, pad) { if (!width || width < 1) return this; if (!pad) pad = " "; var length = width - this.length if (length < 1) return this.substr(0, width); return (String.repeat(pad, length) + this).substr(0, width); } String.repeat = function (chr, count) { var str = ""; for (var x = 0; x < count; x++) { str += chr }; return str; } })(jQuery); The plugin consists of the actual plugin and the Time class which handles parsing and formatting of the time value via the .parse() and .toString() methods. Code like this always ends up taking up more effort than the actual logic unfortunately. There are libraries out there that can handle this like datejs or even ww.jquery.js (which is what I use) but to keep the code self contained for this post the plugin doesn't rely on external code. There's one optional exception: The code as is has one dependency on ww.jquery.js  for the tooltip plugin that provides the small popup for all the hotkeys available. You can replace that code with some other mechanism to display hotkeys or simply remove it since that behavior is optional. While we're at it: A jQuery dateKeys plugIn Although date entry tends to be much better served with drop down calendars to pick dates from, often it's also easier to pick dates using a few simple hotkeys. Navigation that uses + - for days and M and H for MontH navigation, Y and R for YeaR navigation are a quick way to enter dates without having to resort to using a mouse and clicking around to what you want to find. Note that this plugin does have a dependency on ww.jquery.js for the date formatting functionality.$.fn.dateKeys = function (options) { /// <summary> /// Attaches a set of hotkeys to date 'fields' /// + Add day - subtract day /// M Subtract Month H Add montH /// Y Subtract Year R Add yeaR /// ? Show keys /// </summary> /// <param name="options" type="object"> /// Options: /// dateFormat: "MM/dd/yyyy" by default "MMM dd, yyyy /// callback: callback handler after date assignment /// </param> /// <example> /// var proxy = new ServiceProxy("JsonStockService.svc/"); /// proxy.invoke("GetStockQuote",{symbol:"msft"},function(quote) { alert(result.LastPrice); },onPageError); ///</example> if (this.length < 1) return this; var opt = { dateFormat: "MM/dd/yyyy", callback: null }; $.extend(opt, options); return this.keydown(function (e) { var $el = $(this); var d = new Date($el.val()); if (!d) d = new Date(1900, 0, 1, 1, 1); var month = d.getMonth(); var year = d.getFullYear(); var day = d.getDate(); switch (e.keyCode) { case 84: // [T]oday d = new Date(); break; case 109: case 189: d = new Date(year, month, day - 1); break; case 107: case 187: d = new Date(year, month, day + 1); break; case 77: //M d = new Date(year, month - 1, day); break; case 72: //H d = new Date(year, month + 1, day); break; case 191: // ? if (e.shiftKey) $el.tooltip("<b>T</b> Today<br/><b>+</b> add day<br /><b>-</b> subtract day<br /><b>M</b> subtract Month<br /><b>H</b> add montH<br/><b>Y</b> subtract Year<br/><b>R</b> add yeaR", 5000, { isHtml: true }); return false; default: return true; } $el.val(d.formatDate(opt.dateFormat)); if (opt.callback) // call async setTimeout(function () { opt.callback.call($el.get(0),d); }, 10); return false; }); } The logic for this plugin is similar to the timeKeys plugin, but it's a little simpler as it tries to directly parse the date value from a string via new Date(inputString). As mentioned it also uses a helper function from ww.jquery.js to format dates which removes the logic to perform date formatting manually which again reduces the size of the code. And the Key is… I've been using both of these plugins in combination with the jQuery UI datepicker for datetime values and I've found that I rarely actually pop up the date picker any more. It's just so much more efficient to use the hotkeys to navigate dates. It's still nice to have the picker around though - it provides the expected behavior for date entry. For time values however I can't justify the UI overhead of a picker that doesn't make it any easier to pick a time. Most people know how to type in a time value and if they want shortcuts keystrokes easily beat out any pop up UI. Hopefully you'll find this as useful as I have found it for my code. Resources Online Sample Download Sample Project © Rick Strahl, West Wind Technologies, 2005-2011Posted in jQuery  HTML   Tweet (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

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• Introduction to the ASP.NET Web API

  - by Stephen.Walther

  I am a huge fan of Ajax. If you want to create a great experience for the users of your website – regardless of whether you are building an ASP.NET MVC or an ASP.NET Web Forms site — then you need to use Ajax. Otherwise, you are just being cruel to your customers. We use Ajax extensively in several of the ASP.NET applications that my company, Superexpert.com, builds. We expose data from the server as JSON and use jQuery to retrieve and update that data from the browser. One challenge, when building an ASP.NET website, is deciding on which technology to use to expose JSON data from the server. For example, how do you expose a list of products from the server as JSON so you can retrieve the list of products with jQuery? You have a number of options (too many options) including ASMX Web services, WCF Web Services, ASHX Generic Handlers, WCF Data Services, and MVC controller actions. Fortunately, the world has just been simplified. With the release of ASP.NET 4 Beta, Microsoft has introduced a new technology for exposing JSON from the server named the ASP.NET Web API. You can use the ASP.NET Web API with both ASP.NET MVC and ASP.NET Web Forms applications. The goal of this blog post is to provide you with a brief overview of the features of the new ASP.NET Web API. You learn how to use the ASP.NET Web API to retrieve, insert, update, and delete database records with jQuery. We also discuss how you can perform form validation when using the Web API and use OData when using the Web API. Creating an ASP.NET Web API Controller The ASP.NET Web API exposes JSON data through a new type of controller called an API controller. You can add an API controller to an existing ASP.NET MVC 4 project through the standard Add Controller dialog box. Right-click your Controllers folder and select Add, Controller. In the dialog box, name your controller MovieController and select the Empty API controller template: A brand new API controller looks like this: using System; using System.Collections.Generic; using System.Linq; using System.Net.Http; using System.Web.Http; namespace MyWebAPIApp.Controllers { public class MovieController : ApiController { } } An API controller, unlike a standard MVC controller, derives from the base ApiController class instead of the base Controller class. Using jQuery to Retrieve, Insert, Update, and Delete Data Let’s create an Ajaxified Movie Database application. We’ll retrieve, insert, update, and delete movies using jQuery with the MovieController which we just created. Our Movie model class looks like this: namespace MyWebAPIApp.Models { public class Movie { public int Id { get; set; } public string Title { get; set; } public string Director { get; set; } } } Our application will consist of a single HTML page named Movies.html. We’ll place all of our jQuery code in the Movies.html page. Getting a Single Record with the ASP.NET Web API To support retrieving a single movie from the server, we need to add a Get method to our API controller: using System; using System.Collections.Generic; using System.Linq; using System.Net; using System.Net.Http; using System.Web.Http; using MyWebAPIApp.Models; namespace MyWebAPIApp.Controllers { public class MovieController : ApiController { public Movie GetMovie(int id) { // Return movie by id if (id == 1) { return new Movie { Id = 1, Title = "Star Wars", Director = "Lucas" }; } // Otherwise, movie was not found throw new HttpResponseException(HttpStatusCode.NotFound); } } } In the code above, the GetMovie() method accepts the Id of a movie. If the Id has the value 1 then the method returns the movie Star Wars. Otherwise, the method throws an exception and returns 404 Not Found HTTP status code. After building your project, you can invoke the MovieController.GetMovie() method by entering the following URL in your web browser address bar: http://localhost:[port]/api/movie/1 (You’ll need to enter the correct randomly generated port). In the URL api/movie/1, the first “api” segment indicates that this is a Web API route. The “movie” segment indicates that the MovieController should be invoked. You do not specify the name of the action. Instead, the HTTP method used to make the request – GET, POST, PUT, DELETE — is used to identify the action to invoke. The ASP.NET Web API uses different routing conventions than normal ASP.NET MVC controllers. When you make an HTTP GET request then any API controller method with a name that starts with “GET” is invoked. So, we could have called our API controller action GetPopcorn() instead of GetMovie() and it would still be invoked by the URL api/movie/1. The default route for the Web API is defined in the Global.asax file and it looks like this: routes.MapHttpRoute( name: "DefaultApi", routeTemplate: "api/{controller}/{id}", defaults: new { id = RouteParameter.Optional } ); We can invoke our GetMovie() controller action with the jQuery code in the following HTML page: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Get Movie</title> </head> <body> <div> Title: <span id="title"></span> </div> <div> Director: <span id="director"></span> </div> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> getMovie(1, function (movie) { $("#title").html(movie.Title); $("#director").html(movie.Director); }); function getMovie(id, callback) { $.ajax({ url: "/api/Movie", data: { id: id }, type: "GET", contentType: "application/json;charset=utf-8", statusCode: { 200: function (movie) { callback(movie); }, 404: function () { alert("Not Found!"); } } }); } </script> </body> </html> In the code above, the jQuery $.ajax() method is used to invoke the GetMovie() method. Notice that the Ajax call handles two HTTP response codes. When the GetMove() method successfully returns a movie, the method returns a 200 status code. In that case, the details of the movie are displayed in the HTML page. Otherwise, if the movie is not found, the GetMovie() method returns a 404 status code. In that case, the page simply displays an alert box indicating that the movie was not found (hopefully, you would implement something more graceful in an actual application). You can use your browser’s Developer Tools to see what is going on in the background when you open the HTML page (hit F12 in the most recent version of most browsers). For example, you can use the Network tab in Google Chrome to see the Ajax request which invokes the GetMovie() method: Getting a Set of Records with the ASP.NET Web API Let’s modify our Movie API controller so that it returns a collection of movies. The following Movie controller has a new ListMovies() method which returns a (hard-coded) collection of movies: using System; using System.Collections.Generic; using System.Linq; using System.Net; using System.Net.Http; using System.Web.Http; using MyWebAPIApp.Models; namespace MyWebAPIApp.Controllers { public class MovieController : ApiController { public IEnumerable<Movie> ListMovies() { return new List<Movie> { new Movie {Id=1, Title="Star Wars", Director="Lucas"}, new Movie {Id=1, Title="King Kong", Director="Jackson"}, new Movie {Id=1, Title="Memento", Director="Nolan"} }; } } } Because we named our action ListMovies(), the default Web API route will never match it. Therefore, we need to add the following custom route to our Global.asax file (at the top of the RegisterRoutes() method): routes.MapHttpRoute( name: "ActionApi", routeTemplate: "api/{controller}/{action}/{id}", defaults: new { id = RouteParameter.Optional } ); This route enables us to invoke the ListMovies() method with the URL /api/movie/listmovies. Now that we have exposed our collection of movies from the server, we can retrieve and display the list of movies using jQuery in our HTML page: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>List Movies</title> </head> <body> <div id="movies"></div> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> listMovies(function (movies) { var strMovies=""; $.each(movies, function (index, movie) { strMovies += "<div>" + movie.Title + "</div>"; }); $("#movies").html(strMovies); }); function listMovies(callback) { $.ajax({ url: "/api/Movie/ListMovies", data: {}, type: "GET", contentType: "application/json;charset=utf-8", }).then(function(movies){ callback(movies); }); } </script> </body> </html>     Inserting a Record with the ASP.NET Web API Now let’s modify our Movie API controller so it supports creating new records: public HttpResponseMessage<Movie> PostMovie(Movie movieToCreate) { // Add movieToCreate to the database and update primary key movieToCreate.Id = 23; // Build a response that contains the location of the new movie var response = new HttpResponseMessage<Movie>(movieToCreate, HttpStatusCode.Created); var relativePath = "/api/movie/" + movieToCreate.Id; response.Headers.Location = new Uri(Request.RequestUri, relativePath); return response; } The PostMovie() method in the code above accepts a movieToCreate parameter. We don’t actually store the new movie anywhere. In real life, you will want to call a service method to store the new movie in a database. When you create a new resource, such as a new movie, you should return the location of the new resource. In the code above, the URL where the new movie can be retrieved is assigned to the Location header returned in the PostMovie() response. Because the name of our method starts with “Post”, we don’t need to create a custom route. The PostMovie() method can be invoked with the URL /Movie/PostMovie – just as long as the method is invoked within the context of a HTTP POST request. The following HTML page invokes the PostMovie() method. <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Create Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> var movieToCreate = { title: "The Hobbit", director: "Jackson" }; createMovie(movieToCreate, function (newMovie) { alert("New movie created with an Id of " + newMovie.Id); }); function createMovie(movieToCreate, callback) { $.ajax({ url: "/api/Movie", data: JSON.stringify( movieToCreate ), type: "POST", contentType: "application/json;charset=utf-8", statusCode: { 201: function (newMovie) { callback(newMovie); } } }); } </script> </body> </html> This page creates a new movie (the Hobbit) by calling the createMovie() method. The page simply displays the Id of the new movie: The HTTP Post operation is performed with the following call to the jQuery $.ajax() method: $.ajax({ url: "/api/Movie", data: JSON.stringify( movieToCreate ), type: "POST", contentType: "application/json;charset=utf-8", statusCode: { 201: function (newMovie) { callback(newMovie); } } }); Notice that the type of Ajax request is a POST request. This is required to match the PostMovie() method. Notice, furthermore, that the new movie is converted into JSON using JSON.stringify(). The JSON.stringify() method takes a JavaScript object and converts it into a JSON string. Finally, notice that success is represented with a 201 status code. The HttpStatusCode.Created value returned from the PostMovie() method returns a 201 status code. Updating a Record with the ASP.NET Web API Here’s how we can modify the Movie API controller to support updating an existing record. In this case, we need to create a PUT method to handle an HTTP PUT request: public void PutMovie(Movie movieToUpdate) { if (movieToUpdate.Id == 1) { // Update the movie in the database return; } // If you can't find the movie to update throw new HttpResponseException(HttpStatusCode.NotFound); } Unlike our PostMovie() method, the PutMovie() method does not return a result. The action either updates the database or, if the movie cannot be found, returns an HTTP Status code of 404. The following HTML page illustrates how you can invoke the PutMovie() method: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Put Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> var movieToUpdate = { id: 1, title: "The Hobbit", director: "Jackson" }; updateMovie(movieToUpdate, function () { alert("Movie updated!"); }); function updateMovie(movieToUpdate, callback) { $.ajax({ url: "/api/Movie", data: JSON.stringify(movieToUpdate), type: "PUT", contentType: "application/json;charset=utf-8", statusCode: { 200: function () { callback(); }, 404: function () { alert("Movie not found!"); } } }); } </script> </body> </html> Deleting a Record with the ASP.NET Web API Here’s the code for deleting a movie: public HttpResponseMessage DeleteMovie(int id) { // Delete the movie from the database // Return status code return new HttpResponseMessage(HttpStatusCode.NoContent); } This method simply deletes the movie (well, not really, but pretend that it does) and returns a No Content status code (204). The following page illustrates how you can invoke the DeleteMovie() action: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Delete Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> deleteMovie(1, function () { alert("Movie deleted!"); }); function deleteMovie(id, callback) { $.ajax({ url: "/api/Movie", data: JSON.stringify({id:id}), type: "DELETE", contentType: "application/json;charset=utf-8", statusCode: { 204: function () { callback(); } } }); } </script> </body> </html> Performing Validation How do you perform form validation when using the ASP.NET Web API? Because validation in ASP.NET MVC is driven by the Default Model Binder, and because the Web API uses the Default Model Binder, you get validation for free. Let’s modify our Movie class so it includes some of the standard validation attributes: using System.ComponentModel.DataAnnotations; namespace MyWebAPIApp.Models { public class Movie { public int Id { get; set; } [Required(ErrorMessage="Title is required!")] [StringLength(5, ErrorMessage="Title cannot be more than 5 characters!")] public string Title { get; set; } [Required(ErrorMessage="Director is required!")] public string Director { get; set; } } } In the code above, the Required validation attribute is used to make both the Title and Director properties required. The StringLength attribute is used to require the length of the movie title to be no more than 5 characters. Now let’s modify our PostMovie() action to validate a movie before adding the movie to the database: public HttpResponseMessage PostMovie(Movie movieToCreate) { // Validate movie if (!ModelState.IsValid) { var errors = new JsonArray(); foreach (var prop in ModelState.Values) { if (prop.Errors.Any()) { errors.Add(prop.Errors.First().ErrorMessage); } } return new HttpResponseMessage<JsonValue>(errors, HttpStatusCode.BadRequest); } // Add movieToCreate to the database and update primary key movieToCreate.Id = 23; // Build a response that contains the location of the new movie var response = new HttpResponseMessage<Movie>(movieToCreate, HttpStatusCode.Created); var relativePath = "/api/movie/" + movieToCreate.Id; response.Headers.Location = new Uri(Request.RequestUri, relativePath); return response; } If ModelState.IsValid has the value false then the errors in model state are copied to a new JSON array. Each property – such as the Title and Director property — can have multiple errors. In the code above, only the first error message is copied over. The JSON array is returned with a Bad Request status code (400 status code). The following HTML page illustrates how you can invoke our modified PostMovie() action and display any error messages: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Create Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> var movieToCreate = { title: "The Hobbit", director: "" }; createMovie(movieToCreate, function (newMovie) { alert("New movie created with an Id of " + newMovie.Id); }, function (errors) { var strErrors = ""; $.each(errors, function(index, err) { strErrors += "*" + err + "\n"; }); alert(strErrors); } ); function createMovie(movieToCreate, success, fail) { $.ajax({ url: "/api/Movie", data: JSON.stringify(movieToCreate), type: "POST", contentType: "application/json;charset=utf-8", statusCode: { 201: function (newMovie) { success(newMovie); }, 400: function (xhr) { var errors = JSON.parse(xhr.responseText); fail(errors); } } }); } </script> </body> </html> The createMovie() function performs an Ajax request and handles either a 201 or a 400 status code from the response. If a 201 status code is returned then there were no validation errors and the new movie was created. If, on the other hand, a 400 status code is returned then there was a validation error. The validation errors are retrieved from the XmlHttpRequest responseText property. The error messages are displayed in an alert: (Please don’t use JavaScript alert dialogs to display validation errors, I just did it this way out of pure laziness) This validation code in our PostMovie() method is pretty generic. There is nothing specific about this code to the PostMovie() method. In the following video, Jon Galloway demonstrates how to create a global Validation filter which can be used with any API controller action: http://www.asp.net/web-api/overview/web-api-routing-and-actions/video-custom-validation His validation filter looks like this: using System.Json; using System.Linq; using System.Net; using System.Net.Http; using System.Web.Http.Controllers; using System.Web.Http.Filters; namespace MyWebAPIApp.Filters { public class ValidationActionFilter:ActionFilterAttribute { public override void OnActionExecuting(HttpActionContext actionContext) { var modelState = actionContext.ModelState; if (!modelState.IsValid) { dynamic errors = new JsonObject(); foreach (var key in modelState.Keys) { var state = modelState[key]; if (state.Errors.Any()) { errors[key] = state.Errors.First().ErrorMessage; } } actionContext.Response = new HttpResponseMessage<JsonValue>(errors, HttpStatusCode.BadRequest); } } } } And you can register the validation filter in the Application_Start() method in the Global.asax file like this: GlobalConfiguration.Configuration.Filters.Add(new ValidationActionFilter()); After you register the Validation filter, validation error messages are returned from any API controller action method automatically when validation fails. You don’t need to add any special logic to any of your API controller actions to take advantage of the filter. Querying using OData The OData protocol is an open protocol created by Microsoft which enables you to perform queries over the web. The official website for OData is located here: http://odata.org For example, here are some of the query options which you can use with OData: · $orderby – Enables you to retrieve results in a certain order. · $top – Enables you to retrieve a certain number of results. · $skip – Enables you to skip over a certain number of results (use with $top for paging). · $filter – Enables you to filter the results returned. The ASP.NET Web API supports a subset of the OData protocol. You can use all of the query options listed above when interacting with an API controller. The only requirement is that the API controller action returns its data as IQueryable. For example, the following Movie controller has an action named GetMovies() which returns an IQueryable of movies: public IQueryable<Movie> GetMovies() { return new List<Movie> { new Movie {Id=1, Title="Star Wars", Director="Lucas"}, new Movie {Id=2, Title="King Kong", Director="Jackson"}, new Movie {Id=3, Title="Willow", Director="Lucas"}, new Movie {Id=4, Title="Shrek", Director="Smith"}, new Movie {Id=5, Title="Memento", Director="Nolan"} }.AsQueryable(); } If you enter the following URL in your browser: /api/movie?$top=2&$orderby=Title Then you will limit the movies returned to the top 2 in order of the movie Title. You will get the following results: By using the $top option in combination with the $skip option, you can enable client-side paging. For example, you can use $top and $skip to page through thousands of products, 10 products at a time. The $filter query option is very powerful. You can use this option to filter the results from a query. Here are some examples: Return every movie directed by Lucas: /api/movie?$filter=Director eq ‘Lucas’ Return every movie which has a title which starts with ‘S’: /api/movie?$filter=startswith(Title,’S') Return every movie which has an Id greater than 2: /api/movie?$filter=Id gt 2 The complete documentation for the $filter option is located here: http://www.odata.org/developers/protocols/uri-conventions#FilterSystemQueryOption Summary The goal of this blog entry was to provide you with an overview of the new ASP.NET Web API introduced with the Beta release of ASP.NET 4. In this post, I discussed how you can retrieve, insert, update, and delete data by using jQuery with the Web API. I also discussed how you can use the standard validation attributes with the Web API. You learned how to return validation error messages to the client and display the error messages using jQuery. Finally, we briefly discussed how the ASP.NET Web API supports the OData protocol. For example, you learned how to filter records returned from an API controller action by using the $filter query option. I’m excited about the new Web API. This is a feature which I expect to use with almost every ASP.NET application which I build in the future.

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• Introduction to the ASP.NET Web API

  - by Stephen.Walther

  I am a huge fan of Ajax. If you want to create a great experience for the users of your website – regardless of whether you are building an ASP.NET MVC or an ASP.NET Web Forms site — then you need to use Ajax. Otherwise, you are just being cruel to your customers. We use Ajax extensively in several of the ASP.NET applications that my company, Superexpert.com, builds. We expose data from the server as JSON and use jQuery to retrieve and update that data from the browser. One challenge, when building an ASP.NET website, is deciding on which technology to use to expose JSON data from the server. For example, how do you expose a list of products from the server as JSON so you can retrieve the list of products with jQuery? You have a number of options (too many options) including ASMX Web services, WCF Web Services, ASHX Generic Handlers, WCF Data Services, and MVC controller actions. Fortunately, the world has just been simplified. With the release of ASP.NET 4 Beta, Microsoft has introduced a new technology for exposing JSON from the server named the ASP.NET Web API. You can use the ASP.NET Web API with both ASP.NET MVC and ASP.NET Web Forms applications. The goal of this blog post is to provide you with a brief overview of the features of the new ASP.NET Web API. You learn how to use the ASP.NET Web API to retrieve, insert, update, and delete database records with jQuery. We also discuss how you can perform form validation when using the Web API and use OData when using the Web API. Creating an ASP.NET Web API Controller The ASP.NET Web API exposes JSON data through a new type of controller called an API controller. You can add an API controller to an existing ASP.NET MVC 4 project through the standard Add Controller dialog box. Right-click your Controllers folder and select Add, Controller. In the dialog box, name your controller MovieController and select the Empty API controller template: A brand new API controller looks like this: using System; using System.Collections.Generic; using System.Linq; using System.Net.Http; using System.Web.Http; namespace MyWebAPIApp.Controllers { public class MovieController : ApiController { } } An API controller, unlike a standard MVC controller, derives from the base ApiController class instead of the base Controller class. Using jQuery to Retrieve, Insert, Update, and Delete Data Let’s create an Ajaxified Movie Database application. We’ll retrieve, insert, update, and delete movies using jQuery with the MovieController which we just created. Our Movie model class looks like this: namespace MyWebAPIApp.Models { public class Movie { public int Id { get; set; } public string Title { get; set; } public string Director { get; set; } } } Our application will consist of a single HTML page named Movies.html. We’ll place all of our jQuery code in the Movies.html page. Getting a Single Record with the ASP.NET Web API To support retrieving a single movie from the server, we need to add a Get method to our API controller: using System; using System.Collections.Generic; using System.Linq; using System.Net; using System.Net.Http; using System.Web.Http; using MyWebAPIApp.Models; namespace MyWebAPIApp.Controllers { public class MovieController : ApiController { public Movie GetMovie(int id) { // Return movie by id if (id == 1) { return new Movie { Id = 1, Title = "Star Wars", Director = "Lucas" }; } // Otherwise, movie was not found throw new HttpResponseException(HttpStatusCode.NotFound); } } } In the code above, the GetMovie() method accepts the Id of a movie. If the Id has the value 1 then the method returns the movie Star Wars. Otherwise, the method throws an exception and returns 404 Not Found HTTP status code. After building your project, you can invoke the MovieController.GetMovie() method by entering the following URL in your web browser address bar: http://localhost:[port]/api/movie/1 (You’ll need to enter the correct randomly generated port). In the URL api/movie/1, the first “api” segment indicates that this is a Web API route. The “movie” segment indicates that the MovieController should be invoked. You do not specify the name of the action. Instead, the HTTP method used to make the request – GET, POST, PUT, DELETE — is used to identify the action to invoke. The ASP.NET Web API uses different routing conventions than normal ASP.NET MVC controllers. When you make an HTTP GET request then any API controller method with a name that starts with “GET” is invoked. So, we could have called our API controller action GetPopcorn() instead of GetMovie() and it would still be invoked by the URL api/movie/1. The default route for the Web API is defined in the Global.asax file and it looks like this: routes.MapHttpRoute( name: "DefaultApi", routeTemplate: "api/{controller}/{id}", defaults: new { id = RouteParameter.Optional } ); We can invoke our GetMovie() controller action with the jQuery code in the following HTML page: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Get Movie</title> </head> <body> <div> Title: <span id="title"></span> </div> <div> Director: <span id="director"></span> </div> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> getMovie(1, function (movie) { $("#title").html(movie.Title); $("#director").html(movie.Director); }); function getMovie(id, callback) { $.ajax({ url: "/api/Movie", data: { id: id }, type: "GET", contentType: "application/json;charset=utf-8", statusCode: { 200: function (movie) { callback(movie); }, 404: function () { alert("Not Found!"); } } }); } </script> </body> </html> In the code above, the jQuery $.ajax() method is used to invoke the GetMovie() method. Notice that the Ajax call handles two HTTP response codes. When the GetMove() method successfully returns a movie, the method returns a 200 status code. In that case, the details of the movie are displayed in the HTML page. Otherwise, if the movie is not found, the GetMovie() method returns a 404 status code. In that case, the page simply displays an alert box indicating that the movie was not found (hopefully, you would implement something more graceful in an actual application). You can use your browser’s Developer Tools to see what is going on in the background when you open the HTML page (hit F12 in the most recent version of most browsers). For example, you can use the Network tab in Google Chrome to see the Ajax request which invokes the GetMovie() method: Getting a Set of Records with the ASP.NET Web API Let’s modify our Movie API controller so that it returns a collection of movies. The following Movie controller has a new ListMovies() method which returns a (hard-coded) collection of movies: using System; using System.Collections.Generic; using System.Linq; using System.Net; using System.Net.Http; using System.Web.Http; using MyWebAPIApp.Models; namespace MyWebAPIApp.Controllers { public class MovieController : ApiController { public IEnumerable<Movie> ListMovies() { return new List<Movie> { new Movie {Id=1, Title="Star Wars", Director="Lucas"}, new Movie {Id=1, Title="King Kong", Director="Jackson"}, new Movie {Id=1, Title="Memento", Director="Nolan"} }; } } } Because we named our action ListMovies(), the default Web API route will never match it. Therefore, we need to add the following custom route to our Global.asax file (at the top of the RegisterRoutes() method): routes.MapHttpRoute( name: "ActionApi", routeTemplate: "api/{controller}/{action}/{id}", defaults: new { id = RouteParameter.Optional } ); This route enables us to invoke the ListMovies() method with the URL /api/movie/listmovies. Now that we have exposed our collection of movies from the server, we can retrieve and display the list of movies using jQuery in our HTML page: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>List Movies</title> </head> <body> <div id="movies"></div> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> listMovies(function (movies) { var strMovies=""; $.each(movies, function (index, movie) { strMovies += "<div>" + movie.Title + "</div>"; }); $("#movies").html(strMovies); }); function listMovies(callback) { $.ajax({ url: "/api/Movie/ListMovies", data: {}, type: "GET", contentType: "application/json;charset=utf-8", }).then(function(movies){ callback(movies); }); } </script> </body> </html>     Inserting a Record with the ASP.NET Web API Now let’s modify our Movie API controller so it supports creating new records: public HttpResponseMessage<Movie> PostMovie(Movie movieToCreate) { // Add movieToCreate to the database and update primary key movieToCreate.Id = 23; // Build a response that contains the location of the new movie var response = new HttpResponseMessage<Movie>(movieToCreate, HttpStatusCode.Created); var relativePath = "/api/movie/" + movieToCreate.Id; response.Headers.Location = new Uri(Request.RequestUri, relativePath); return response; } The PostMovie() method in the code above accepts a movieToCreate parameter. We don’t actually store the new movie anywhere. In real life, you will want to call a service method to store the new movie in a database. When you create a new resource, such as a new movie, you should return the location of the new resource. In the code above, the URL where the new movie can be retrieved is assigned to the Location header returned in the PostMovie() response. Because the name of our method starts with “Post”, we don’t need to create a custom route. The PostMovie() method can be invoked with the URL /Movie/PostMovie – just as long as the method is invoked within the context of a HTTP POST request. The following HTML page invokes the PostMovie() method. <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Create Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> var movieToCreate = { title: "The Hobbit", director: "Jackson" }; createMovie(movieToCreate, function (newMovie) { alert("New movie created with an Id of " + newMovie.Id); }); function createMovie(movieToCreate, callback) { $.ajax({ url: "/api/Movie", data: JSON.stringify( movieToCreate ), type: "POST", contentType: "application/json;charset=utf-8", statusCode: { 201: function (newMovie) { callback(newMovie); } } }); } </script> </body> </html> This page creates a new movie (the Hobbit) by calling the createMovie() method. The page simply displays the Id of the new movie: The HTTP Post operation is performed with the following call to the jQuery $.ajax() method: $.ajax({ url: "/api/Movie", data: JSON.stringify( movieToCreate ), type: "POST", contentType: "application/json;charset=utf-8", statusCode: { 201: function (newMovie) { callback(newMovie); } } }); Notice that the type of Ajax request is a POST request. This is required to match the PostMovie() method. Notice, furthermore, that the new movie is converted into JSON using JSON.stringify(). The JSON.stringify() method takes a JavaScript object and converts it into a JSON string. Finally, notice that success is represented with a 201 status code. The HttpStatusCode.Created value returned from the PostMovie() method returns a 201 status code. Updating a Record with the ASP.NET Web API Here’s how we can modify the Movie API controller to support updating an existing record. In this case, we need to create a PUT method to handle an HTTP PUT request: public void PutMovie(Movie movieToUpdate) { if (movieToUpdate.Id == 1) { // Update the movie in the database return; } // If you can't find the movie to update throw new HttpResponseException(HttpStatusCode.NotFound); } Unlike our PostMovie() method, the PutMovie() method does not return a result. The action either updates the database or, if the movie cannot be found, returns an HTTP Status code of 404. The following HTML page illustrates how you can invoke the PutMovie() method: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Put Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> var movieToUpdate = { id: 1, title: "The Hobbit", director: "Jackson" }; updateMovie(movieToUpdate, function () { alert("Movie updated!"); }); function updateMovie(movieToUpdate, callback) { $.ajax({ url: "/api/Movie", data: JSON.stringify(movieToUpdate), type: "PUT", contentType: "application/json;charset=utf-8", statusCode: { 200: function () { callback(); }, 404: function () { alert("Movie not found!"); } } }); } </script> </body> </html> Deleting a Record with the ASP.NET Web API Here’s the code for deleting a movie: public HttpResponseMessage DeleteMovie(int id) { // Delete the movie from the database // Return status code return new HttpResponseMessage(HttpStatusCode.NoContent); } This method simply deletes the movie (well, not really, but pretend that it does) and returns a No Content status code (204). The following page illustrates how you can invoke the DeleteMovie() action: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Delete Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> deleteMovie(1, function () { alert("Movie deleted!"); }); function deleteMovie(id, callback) { $.ajax({ url: "/api/Movie", data: JSON.stringify({id:id}), type: "DELETE", contentType: "application/json;charset=utf-8", statusCode: { 204: function () { callback(); } } }); } </script> </body> </html> Performing Validation How do you perform form validation when using the ASP.NET Web API? Because validation in ASP.NET MVC is driven by the Default Model Binder, and because the Web API uses the Default Model Binder, you get validation for free. Let’s modify our Movie class so it includes some of the standard validation attributes: using System.ComponentModel.DataAnnotations; namespace MyWebAPIApp.Models { public class Movie { public int Id { get; set; } [Required(ErrorMessage="Title is required!")] [StringLength(5, ErrorMessage="Title cannot be more than 5 characters!")] public string Title { get; set; } [Required(ErrorMessage="Director is required!")] public string Director { get; set; } } } In the code above, the Required validation attribute is used to make both the Title and Director properties required. The StringLength attribute is used to require the length of the movie title to be no more than 5 characters. Now let’s modify our PostMovie() action to validate a movie before adding the movie to the database: public HttpResponseMessage PostMovie(Movie movieToCreate) { // Validate movie if (!ModelState.IsValid) { var errors = new JsonArray(); foreach (var prop in ModelState.Values) { if (prop.Errors.Any()) { errors.Add(prop.Errors.First().ErrorMessage); } } return new HttpResponseMessage<JsonValue>(errors, HttpStatusCode.BadRequest); } // Add movieToCreate to the database and update primary key movieToCreate.Id = 23; // Build a response that contains the location of the new movie var response = new HttpResponseMessage<Movie>(movieToCreate, HttpStatusCode.Created); var relativePath = "/api/movie/" + movieToCreate.Id; response.Headers.Location = new Uri(Request.RequestUri, relativePath); return response; } If ModelState.IsValid has the value false then the errors in model state are copied to a new JSON array. Each property – such as the Title and Director property — can have multiple errors. In the code above, only the first error message is copied over. The JSON array is returned with a Bad Request status code (400 status code). The following HTML page illustrates how you can invoke our modified PostMovie() action and display any error messages: <!DOCTYPE html> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Create Movie</title> </head> <body> <script type="text/javascript" src="Scripts/jquery-1.6.2.min.js"></script> <script type="text/javascript"> var movieToCreate = { title: "The Hobbit", director: "" }; createMovie(movieToCreate, function (newMovie) { alert("New movie created with an Id of " + newMovie.Id); }, function (errors) { var strErrors = ""; $.each(errors, function(index, err) { strErrors += "*" + err + "n"; }); alert(strErrors); } ); function createMovie(movieToCreate, success, fail) { $.ajax({ url: "/api/Movie", data: JSON.stringify(movieToCreate), type: "POST", contentType: "application/json;charset=utf-8", statusCode: { 201: function (newMovie) { success(newMovie); }, 400: function (xhr) { var errors = JSON.parse(xhr.responseText); fail(errors); } } }); } </script> </body> </html> The createMovie() function performs an Ajax request and handles either a 201 or a 400 status code from the response. If a 201 status code is returned then there were no validation errors and the new movie was created. If, on the other hand, a 400 status code is returned then there was a validation error. The validation errors are retrieved from the XmlHttpRequest responseText property. The error messages are displayed in an alert: (Please don’t use JavaScript alert dialogs to display validation errors, I just did it this way out of pure laziness) This validation code in our PostMovie() method is pretty generic. There is nothing specific about this code to the PostMovie() method. In the following video, Jon Galloway demonstrates how to create a global Validation filter which can be used with any API controller action: http://www.asp.net/web-api/overview/web-api-routing-and-actions/video-custom-validation His validation filter looks like this: using System.Json; using System.Linq; using System.Net; using System.Net.Http; using System.Web.Http.Controllers; using System.Web.Http.Filters; namespace MyWebAPIApp.Filters { public class ValidationActionFilter:ActionFilterAttribute { public override void OnActionExecuting(HttpActionContext actionContext) { var modelState = actionContext.ModelState; if (!modelState.IsValid) { dynamic errors = new JsonObject(); foreach (var key in modelState.Keys) { var state = modelState[key]; if (state.Errors.Any()) { errors[key] = state.Errors.First().ErrorMessage; } } actionContext.Response = new HttpResponseMessage<JsonValue>(errors, HttpStatusCode.BadRequest); } } } } And you can register the validation filter in the Application_Start() method in the Global.asax file like this: GlobalConfiguration.Configuration.Filters.Add(new ValidationActionFilter()); After you register the Validation filter, validation error messages are returned from any API controller action method automatically when validation fails. You don’t need to add any special logic to any of your API controller actions to take advantage of the filter. Querying using OData The OData protocol is an open protocol created by Microsoft which enables you to perform queries over the web. The official website for OData is located here: http://odata.org For example, here are some of the query options which you can use with OData: · $orderby – Enables you to retrieve results in a certain order. · $top – Enables you to retrieve a certain number of results. · $skip – Enables you to skip over a certain number of results (use with $top for paging). · $filter – Enables you to filter the results returned. The ASP.NET Web API supports a subset of the OData protocol. You can use all of the query options listed above when interacting with an API controller. The only requirement is that the API controller action returns its data as IQueryable. For example, the following Movie controller has an action named GetMovies() which returns an IQueryable of movies: public IQueryable<Movie> GetMovies() { return new List<Movie> { new Movie {Id=1, Title="Star Wars", Director="Lucas"}, new Movie {Id=2, Title="King Kong", Director="Jackson"}, new Movie {Id=3, Title="Willow", Director="Lucas"}, new Movie {Id=4, Title="Shrek", Director="Smith"}, new Movie {Id=5, Title="Memento", Director="Nolan"} }.AsQueryable(); } If you enter the following URL in your browser: /api/movie?$top=2&$orderby=Title Then you will limit the movies returned to the top 2 in order of the movie Title. You will get the following results: By using the $top option in combination with the $skip option, you can enable client-side paging. For example, you can use $top and $skip to page through thousands of products, 10 products at a time. The $filter query option is very powerful. You can use this option to filter the results from a query. Here are some examples: Return every movie directed by Lucas: /api/movie?$filter=Director eq ‘Lucas’ Return every movie which has a title which starts with ‘S’: /api/movie?$filter=startswith(Title,’S') Return every movie which has an Id greater than 2: /api/movie?$filter=Id gt 2 The complete documentation for the $filter option is located here: http://www.odata.org/developers/protocols/uri-conventions#FilterSystemQueryOption Summary The goal of this blog entry was to provide you with an overview of the new ASP.NET Web API introduced with the Beta release of ASP.NET 4. In this post, I discussed how you can retrieve, insert, update, and delete data by using jQuery with the Web API. I also discussed how you can use the standard validation attributes with the Web API. You learned how to return validation error messages to the client and display the error messages using jQuery. Finally, we briefly discussed how the ASP.NET Web API supports the OData protocol. For example, you learned how to filter records returned from an API controller action by using the $filter query option. I’m excited about the new Web API. This is a feature which I expect to use with almost every ASP.NET application which I build in the future.

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• Using BPEL Performance Statistics to Diagnose Performance Bottlenecks

  - by fip

  Tuning performance of Oracle SOA 11G applications could be challenging. Because SOA is a platform for you to build composite applications that connect many applications and "services", when the overall performance is slow, the bottlenecks could be anywhere in the system: the applications/services that SOA connects to, the infrastructure database, or the SOA server itself.How to quickly identify the bottleneck becomes crucial in tuning the overall performance. Fortunately, the BPEL engine in Oracle SOA 11G (and 10G, for that matter) collects BPEL Engine Performance Statistics, which show the latencies of low level BPEL engine activities. The BPEL engine performance statistics can make it a bit easier for you to identify the performance bottleneck. Although the BPEL engine performance statistics are always available, the access to and interpretation of them are somewhat obscure in the early and current (PS5) 11G versions. This blog attempts to offer instructions that help you to enable, retrieve and interpret the performance statistics, before the future versions provides a more pleasant user experience. Overview of BPEL Engine Performance Statistics  SOA BPEL has a feature of collecting some performance statistics and store them in memory. One MBean attribute, StatLastN, configures the size of the memory buffer to store the statistics. This memory buffer is a "moving window", in a way that old statistics will be flushed out by the new if the amount of data exceeds the buffer size. Since the buffer size is limited by StatLastN, impacts of statistics collection on performance is minimal. By default StatLastN=-1, which means no collection of performance data. Once the statistics are collected in the memory buffer, they can be retrieved via another MBean oracle.as.soainfra.bpel:Location=[Server Name],name=BPELEngine,type=BPELEngine.> My friend in Oracle SOA development wrote this simple 'bpelstat' web app that looks up and retrieves the performance data from the MBean and displays it in a human readable form. It does not have beautiful UI but it is fairly useful. Although in Oracle SOA 11.1.1.5 onwards the same statistics can be viewed via a more elegant UI under "request break down" at EM -> SOA Infrastructure -> Service Engines -> BPEL -> Statistics, some unsophisticated minds like mine may still prefer the simplicity of the 'bpelstat' JSP. One thing that simple JSP does do well is that you can save the page and send it to someone to further analyze Follows are the instructions of how to install and invoke the BPEL statistic JSP. My friend in SOA Development will soon blog about interpreting the statistics. Stay tuned. Step1: Enable BPEL Engine Statistics for Each SOA Servers via Enterprise Manager First st you need to set the StatLastN to some number as a way to enable the collection of BPEL Engine Performance Statistics EM Console -> soa-infra(Server Name) -> SOA Infrastructure -> SOA Administration -> BPEL Properties Click on "More BPEL Configuration Properties" Click on attribute "StatLastN", set its value to some integer number. Typically you want to set it 1000 or more. Step 2: Download and Deploy bpelstat.war File to Admin Server, Note: the WAR file contains a JSP that does NOT have any security restriction. You do NOT want to keep in your production server for a long time as it is a security hazard. Deactivate the war once you are done. Download the bpelstat.war to your local PC At WebLogic Console, Go to Deployments -> Install Click on the "upload your file(s)" Click the "Browse" button to upload the deployment to Admin Server Accept the uploaded file as the path, click next Check the default option "Install this deployment as an application" Check "AdminServer" as the target server Finish the rest of the deployment with default settings Console -> Deployments Check the box next to "bpelstat" application Click on the "Start" button. It will change the state of the app from "prepared" to "active" Step 3: Invoke the BPEL Statistic Tool The BPELStat tool merely call the MBean of BPEL server and collects and display the in-memory performance statics. You usually want to do that after some peak loads. Go to http://<admin-server-host>:<admin-server-port>/bpelstat Enter the correct admin hostname, port, username and password Enter the SOA Server Name from which you want to collect the performance statistics. For example, SOA_MS1, etc. Click Submit Keep doing the same for all SOA servers. Step 3: Interpret the BPEL Engine Statistics You will see a few categories of BPEL Statistics from the JSP Page. First it starts with the overall latency of BPEL processes, grouped by synchronous and asynchronous processes. Then it provides the further break down of the measurements through the life time of a BPEL request, which is called the "request break down". 1. Overall latency of BPEL processes The top of the page shows that the elapse time of executing the synchronous process TestSyncBPELProcess from the composite TestComposite averages at about 1543.21ms, while the elapse time of executing the asynchronous process TestAsyncBPELProcess from the composite TestComposite2 averages at about 1765.43ms. The maximum and minimum latency were also shown. Synchronous process statistics <statistics>     <stats key="default/TestComposite!2.0.2-ScopedJMSOSB*soa_bfba2527-a9ba-41a7-95c5-87e49c32f4ff/TestSyncBPELProcess" min="1234" max="4567" average="1543.21" count="1000">     </stats> </statistics> Asynchronous process statistics <statistics>     <stats key="default/TestComposite2!2.0.2-ScopedJMSOSB*soa_bfba2527-a9ba-41a7-95c5-87e49c32f4ff/TestAsyncBPELProcess" min="2234" max="3234" average="1765.43" count="1000">     </stats> </statistics> 2. Request break down Under the overall latency categorized by synchronous and asynchronous processes is the "Request breakdown". Organized by statistic keys, the Request breakdown gives finer grain performance statistics through the life time of the BPEL requests.It uses indention to show the hierarchy of the statistics. Request breakdown <statistics>     <stats key="eng-composite-request" min="0" max="0" average="0.0" count="0">         <stats key="eng-single-request" min="22" max="606" average="258.43" count="277">             <stats key="populate-context" min="0" max="0" average="0.0" count="248"> Please note that in SOA 11.1.1.6, the statistics under Request breakdown is aggregated together cross all the BPEL processes based on statistic keys. It does not differentiate between BPEL processes. If two BPEL processes happen to have the statistic that share same statistic key, the statistics from two BPEL processes will be aggregated together. Keep this in mind when we go through more details below. 2.1 BPEL process activity latencies A very useful measurement in the Request Breakdown is the performance statistics of the BPEL activities you put in your BPEL processes: Assign, Invoke, Receive, etc. The names of the measurement in the JSP page directly come from the names to assign to each BPEL activity. These measurements are under the statistic key "actual-perform" Example 1:  Follows is the measurement for BPEL activity "AssignInvokeCreditProvider_Input", which looks like the Assign activity in a BPEL process that assign an input variable before passing it to the invocation:                                <stats key="AssignInvokeCreditProvider_Input" min="1" max="8" average="1.9" count="153">                                     <stats key="sensor-send-activity-data" min="0" max="1" average="0.0" count="306">                                     </stats>                                     <stats key="sensor-send-variable-data" min="0" max="0" average="0.0" count="153">                                     </stats>                                     <stats key="monitor-send-activity-data" min="0" max="0" average="0.0" count="306">                                     </stats>                                 </stats> Note: because as previously mentioned that the statistics cross all BPEL processes are aggregated together based on statistic keys, if two BPEL processes happen to name their Invoke activity the same name, they will show up at one measurement (i.e. statistic key). Example 2: Follows is the measurement of BPEL activity called "InvokeCreditProvider". You can not only see that by average it takes 3.31ms to finish this call (pretty fast) but also you can see from the further break down that most of this 3.31 ms was spent on the "invoke-service".                                  <stats key="InvokeCreditProvider" min="1" max="13" average="3.31" count="153">                                     <stats key="initiate-correlation-set-again" min="0" max="0" average="0.0" count="153">                                     </stats>                                     <stats key="invoke-service" min="1" max="13" average="3.08" count="153">                                         <stats key="prep-call" min="0" max="1" average="0.04" count="153">                                         </stats>                                     </stats>                                     <stats key="initiate-correlation-set" min="0" max="0" average="0.0" count="153">                                     </stats>                                     <stats key="sensor-send-activity-data" min="0" max="0" average="0.0" count="306">                                     </stats>                                     <stats key="sensor-send-variable-data" min="0" max="0" average="0.0" count="153">                                     </stats>                                     <stats key="monitor-send-activity-data" min="0" max="0" average="0.0" count="306">                                     </stats>                                     <stats key="update-audit-trail" min="0" max="2" average="0.03" count="153">                                     </stats>                                 </stats> 2.2 BPEL engine activity latency Another type of measurements under Request breakdown are the latencies of underlying system level engine activities. These activities are not directly tied to a particular BPEL process or process activity, but they are critical factors in the overall engine performance. These activities include the latency of saving asynchronous requests to database, and latency of process dehydration. My friend Malkit Bhasin is working on providing more information on interpreting the statistics on engine activities on his blog (https://blogs.oracle.com/malkit/). I will update this blog once the information becomes available. Update on 2012-10-02: My friend Malkit Bhasin has published the detail interpretation of the BPEL service engine statistics at his blog http://malkit.blogspot.com/2012/09/oracle-bpel-engine-soa-suite.html.

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• 12.04lts: no network internet

  - by dgermann

  Friends-- Cannot connect reliably to ethernet nor at all to Internet: Symptoms: About 2 weeks ago did an upgrade. Have not been able to connect to ethernet nor Internet. Today, for example, boot up this System76 laptop and there was no network connection. Did sudo mount -a and got some internal network connectivity: doug@ubuntu:/sam$ ping earth PING earth (192.168.0.201) 56(84) bytes of data. 64 bytes from earth (192.168.0.201): icmp_req=1 ttl=64 time=0.160 ms 64 bytes from earth (192.168.0.201): icmp_req=2 ttl=64 time=0.177 ms 64 bytes from earth (192.168.0.201): icmp_req=3 ttl=64 time=0.159 ms ^C --- earth ping statistics --- 3 packets transmitted, 3 received, 0% packet loss, time 1998ms rtt min/avg/max/mdev = 0.159/0.165/0.177/0.013 ms doug@ubuntu:/sam$ ping doug2 PING doug (192.168.0.4) 56(84) bytes of data. ^C --- doug ping statistics --- 3 packets transmitted, 0 received, 100% packet loss, time 1999ms doug@ubuntu:/sam$ ping sharon PING sharon (192.168.0.111) 56(84) bytes of data. 64 bytes from sharon (192.168.0.111): icmp_req=1 ttl=128 time=0.276 ms ^C --- sharon ping statistics --- 6 packets transmitted, 1 received, 83% packet loss, time 5031ms rtt min/avg/max/mdev = 0.276/0.276/0.276/0.000 ms doug@ubuntu:/sam$ ping 192.168.0.1 PING 192.168.0.1 (192.168.0.1) 56(84) bytes of data. ^C --- 192.168.0.1 ping statistics --- 6 packets transmitted, 0 received, 100% packet loss, time 4999ms doug@ubuntu:/sam$ ping earth PING earth (192.168.0.201) 56(84) bytes of data. ^C --- earth ping statistics --- 5 packets transmitted, 0 received, 100% packet loss, time 4032ms doug@ubuntu:/sam$ ping yahoo.com ping: unknown host yahoo.com doug@ubuntu:/sam$ ping ubuntu.com ping: unknown host ubuntu.com doug@ubuntu:/sam$ ping 8.8.8.8 PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data. ^C --- 8.8.8.8 ping statistics --- 14 packets transmitted, 0 received, 100% packet loss, time 13103ms Note that earth is the cifs server, and one time pinging it worked, later failed. Clues: doug@ubuntu:/sam$ grep -i eth /var/log/syslog |tail Aug 23 15:32:46 ubuntu kernel: [ 5328.070401] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 Aug 23 15:32:48 ubuntu kernel: [ 5330.651139] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.5 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=19090 PROTO=2 Aug 23 15:34:51 ubuntu kernel: [ 5453.072279] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 Aug 23 15:34:55 ubuntu kernel: [ 5457.085433] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.10 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=16137 PROTO=2 Aug 23 15:36:56 ubuntu kernel: [ 5578.074492] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 Aug 23 15:37:00 ubuntu kernel: [ 5582.359006] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.10 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=16150 PROTO=2 Aug 23 15:39:01 ubuntu kernel: [ 5703.074410] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 Aug 23 15:39:03 ubuntu kernel: [ 5705.070122] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.10 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=16163 PROTO=2 Aug 23 15:41:06 ubuntu kernel: [ 5828.074387] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 Aug 23 15:41:13 ubuntu kernel: [ 5835.319941] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.5 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=23298 PROTO=2 doug@ubuntu:/sam$ ifconfig -a eth0 Link encap:Ethernet HWaddr [BLANKED] inet addr:192.168.0.7 Bcast:192.168.0.255 Mask:255.255.255.0 inet6 addr: fe80::21b:fcff:fe29:9dfc/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:3961 errors:0 dropped:0 overruns:0 frame:0 TX packets:2007 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:991204 (991.2 KB) TX bytes:252908 (252.9 KB) Interrupt:16 Base address:0xec00 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:2190 errors:0 dropped:0 overruns:0 frame:0 TX packets:2190 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:168052 (168.0 KB) TX bytes:168052 (168.0 KB) wlan0 Link encap:Ethernet HWaddr 00:19:d2:72:5a:0c UP BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) doug@ubuntu:/sam$ iwconfig lo no wireless extensions. wlan0 IEEE 802.11abg ESSID:off/any Mode:Managed Access Point: Not-Associated Tx-Power=15 dBm Retry long limit:7 RTS thr:off Fragment thr:off Power Management:off eth0 no wireless extensions. doug@ubuntu:/sam$ lsmod Module Size Used by des_generic 21191 0 md4 12523 0 nls_iso8859_1 12617 1 nls_cp437 12751 1 vfat 17308 1 fat 55605 1 vfat usb_storage 39646 1 dm_crypt 22528 1 joydev 17393 0 snd_hda_codec_analog 75395 1 snd_hda_intel 32719 2 pcmcia 39826 0 snd_hda_codec 109562 2 snd_hda_codec_analog,snd_hda_intel snd_hwdep 13276 1 snd_hda_codec ip6t_LOG 16846 4 xt_hl 12465 6 ip6t_rt 12473 3 snd_pcm 80916 2 snd_hda_intel,snd_hda_codec nf_conntrack_ipv6 13581 7 nf_defrag_ipv6 13175 1 nf_conntrack_ipv6 ipt_REJECT 12512 1 ipt_LOG 12783 5 xt_limit 12541 12 xt_tcpudp 12531 21 xt_addrtype 12596 4 snd_seq_midi 13132 0 xt_state 12514 14 ip6table_filter 12711 1 ip6_tables 22528 3 ip6t_LOG,ip6t_rt,ip6table_filter nf_conntrack_netbios_ns 12585 0 nf_conntrack_broadcast 12541 1 nf_conntrack_netbios_ns nf_nat_ftp 12595 0 nf_nat 24959 1 nf_nat_ftp nf_conntrack_ipv4 19084 9 nf_nat nf_defrag_ipv4 12649 1 nf_conntrack_ipv4 nf_conntrack_ftp 13183 1 nf_nat_ftp nf_conntrack 73847 8 nf_conntrack_ipv6,xt_state,nf_conntrack_netbios_ns,nf_conntrack_broadcast,nf_nat_ftp,nf_nat,nf_conntrack_ipv4,nf_conntrack_ftp iptable_filter 12706 1 ip_tables 18106 1 iptable_filter snd_rawmidi 25424 1 snd_seq_midi psmouse 86982 0 x_tables 22011 13 ip6t_LOG,xt_hl,ip6t_rt,ipt_REJECT,ipt_LOG,xt_limit,xt_tcpudp,xt_addrtype,xt_state,ip6table_filter,ip6_tables,iptable_filter,ip_tables arc4 12473 2 r592 17808 0 snd_seq_midi_event 14475 1 snd_seq_midi memstick 15857 1 r592 yenta_socket 27465 0 serio_raw 13027 0 pcmcia_rsrc 18367 1 yenta_socket iwl3945 73186 0 pcmcia_core 21511 3 pcmcia,yenta_socket,pcmcia_rsrc iwl_legacy 71334 1 iwl3945 snd_seq 51592 2 snd_seq_midi,snd_seq_midi_event mac80211 436493 2 iwl3945,iwl_legacy snd_timer 28931 2 snd_pcm,snd_seq snd_seq_device 14172 3 snd_seq_midi,snd_rawmidi,snd_seq rfcomm 38139 0 bnep 17830 2 parport_pc 32114 0 bluetooth 158447 10 rfcomm,bnep ppdev 12849 0 cfg80211 178877 3 iwl3945,iwl_legacy,mac80211 asus_laptop 23693 0 sparse_keymap 13658 1 asus_laptop input_polldev 13648 1 asus_laptop nls_utf8 12493 6 cifs 258037 10 snd 62218 13 snd_hda_codec_analog,snd_hda_intel,snd_hda_codec,snd_hwdep,snd_pcm,snd_rawmidi,snd_seq,snd_timer,snd_seq_device soundcore 14635 1 snd mac_hid 13077 0 snd_page_alloc 14108 2 snd_hda_intel,snd_pcm lp 17455 0 parport 40930 3 parport_pc,ppdev,lp i915 428418 3 firewire_ohci 40172 0 sdhci_pci 18324 0 sdhci 28241 1 sdhci_pci firewire_core 56940 1 firewire_ohci crc_itu_t 12627 1 firewire_core r8169 56396 0 drm_kms_helper 45466 1 i915 drm 197641 4 i915,drm_kms_helper i2c_algo_bit 13199 1 i915 video 19115 1 i915 doug@ubuntu:/sam$ dmesg |grep eth [ 0.116936] i2c-core: driver [aat2870] using legacy suspend method [ 0.116939] i2c-core: driver [aat2870] using legacy resume method [ 1.453811] r8169 0000:03:07.0: eth0: RTL8169sb/8110sb at 0xf840ec00, [BLANKED], XID 10000000 IRQ 16 [ 1.453815] r8169 0000:03:07.0: eth0: jumbo features [frames: 7152 bytes, tx checksumming: ok] [ 25.681231] ADDRCONF(NETDEV_UP): eth0: link is not ready [ 154.037318] r8169 0000:03:07.0: eth0: link down [ 154.037329] r8169 0000:03:07.0: eth0: link down [ 154.037596] ADDRCONF(NETDEV_UP): eth0: link is not ready [ 155.583162] r8169 0000:03:07.0: eth0: link up [ 155.583366] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready [ 156.637048] r8169 0000:03:07.0: eth0: link down [ 156.637066] r8169 0000:03:07.0: eth0: link down [ 156.637339] ADDRCONF(NETDEV_UP): eth0: link is not ready [ 156.773699] r8169 0000:03:07.0: eth0: link down [ 156.773983] ADDRCONF(NETDEV_UP): eth0: link is not ready [ 158.456181] r8169 0000:03:07.0: eth0: link up [ 158.456378] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready [ 159.364468] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 162.384496] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.5 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=38877 PROTO=2 [ 166.272457] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 166.422333] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.5 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=40695 PROTO=2 [ 168.736049] eth0: no IPv6 routers present [ 183.572472] r8169 0000:03:07.0: eth0: link down [ 183.572490] r8169 0000:03:07.0: eth0: link down [ 183.572934] ADDRCONF(NETDEV_UP): eth0: link is not ready [ 185.204801] r8169 0000:03:07.0: eth0: link up [ 185.205005] ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready [ 3620.680451] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 3621.068431] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 3624.912973] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.5 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=9118 PROTO=2 [ 3631.088069] eth0: no IPv6 routers present [ 3703.062980] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 3703.465330] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.5 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=9210 PROTO=2 [ 3828.062951] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 3833.617772] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.5 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=9749 PROTO=2 [ 3953.062920] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 3955.675129] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.10 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=15983 PROTO=2 [ 4078.062922] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 4078.386319] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.10 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=15997 PROTO=2 [ 4203.062899] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 4203.559241] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.10 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=16011 PROTO=2 [ 4328.062833] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 4328.930922] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.10 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=16027 PROTO=2 [ 4453.062811] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 4453.950224] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.10 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=16039 PROTO=2 [ 4578.062742] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 4580.626432] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.5 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=13738 PROTO=2 [ 4703.062704] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 4706.310170] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.5 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=15942 PROTO=2 [ 4828.062707] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 4832.174324] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.5 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=16505 PROTO=2 [ 4953.062628] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 4961.469282] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.10 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=16090 PROTO=2 [ 5078.062552] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 5080.776462] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.5 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=17239 PROTO=2 [ 5203.070394] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 5205.358134] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.5 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=17665 PROTO=2 [ 5328.070401] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 5330.651139] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.5 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=19090 PROTO=2 [ 5453.072279] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 5457.085433] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.10 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=16137 PROTO=2 [ 5578.074492] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 5582.359006] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.10 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=16150 PROTO=2 [ 5703.074410] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 5705.070122] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED]--- SRC=192.168.0.10 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=16163 PROTO=2 [ 5828.074387] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED][BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 5835.319941] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED][BLANKED]--- SRC=192.168.0.5 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=23298 PROTO=2 [ 5953.074429] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED][BLANKED]--- SRC=192.168.0.1 DST=224.0.0.1 LEN=32 TOS=0x00 PREC=0xC0 TTL=1 ID=0 DF PROTO=2 [ 5961.925481] [UFW BLOCK] IN=eth0 OUT= MAC=[BLANKED][BLANKED]--- SRC=192.168.0.5 DST=224.0.0.251 LEN=32 TOS=0x00 PREC=0x00 TTL=1 ID=24261 PROTO=2 doug@ubuntu:/sam$ lspci -nnk |grep -iA2 eth 03:07.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8169 PCI Gigabit Ethernet Controller [10ec:8169] (rev 10) Subsystem: ASUSTeK Computer Inc. Device [1043:11e5] Kernel driver in use: r8169 doug@ubuntu:/sam$ route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 0.0.0.0 192.168.0.1 0.0.0.0 UG 0 0 0 eth0 169.254.0.0 0.0.0.0 255.255.0.0 U 1000 0 0 eth0 192.168.0.0 0.0.0.0 255.255.255.0 U 1 0 0 eth0 doug@ubuntu:/sam$ nm-tool NetworkManager Tool State: connected (global) - Device: eth0 [Ifupdown (eth0)] ---------------------------------------------- Type: Wired Driver: r8169 State: connected Default: yes HW Address: [BLANKED] Capabilities: Carrier Detect: yes Speed: 100 Mb/s Wired Properties Carrier: on IPv4 Settings: Address: 192.168.0.7 Prefix: 24 (255.255.255.0) Gateway: 192.168.0.1 DNS: 192.168.0.1 - Device: wlan0 ---------------------------------------------------------------- Type: 802.11 WiFi Driver: iwl3945 State: disconnected Default: no HW Address: 00:19:D2:72:5A:0C Capabilities: Wireless Properties WEP Encryption: yes WPA Encryption: yes WPA2 Encryption: yes Wireless Access Points ATT592: Infra, 30:60:23:76:FE:60, Freq 2437 MHz, Rate 54 Mb/s, Strength 24 WPA WPA2 doug@ubuntu:/sam$ nslookup ubuntu.com ;; connection timed out; no servers could be reached doug@ubuntu:/sam$ dig ubuntuforums.org ; <<>> DiG 9.8.1-P1 <<>> ubuntuforums.org ;; global options: +cmd ;; connection timed out; no servers could be reached doug@ubuntu:/sam$ sudo ifconfig eth0 up doug@ubuntu:/sam$ dhcpcd eth0 The program 'dhcpcd' can be found in the following packages: * dhcpcd * dhcpcd5 Try: sudo apt-get install <selected package> doug@ubuntu:/sam$ lspci -k 00:00.0 Host bridge: Intel Corporation Mobile 945GM/PM/GMS, 943/940GML and 945GT Express Memory Controller Hub (rev 03) Subsystem: ASUSTeK Computer Inc. Device 1297 Kernel driver in use: agpgart-intel 00:02.0 VGA compatible controller: Intel Corporation Mobile 945GM/GMS, 943/940GML Express Integrated Graphics Controller (rev 03) Subsystem: ASUSTeK Computer Inc. Device 1252 Kernel driver in use: i915 Kernel modules: intelfb, i915 00:02.1 Display controller: Intel Corporation Mobile 945GM/GMS/GME, 943/940GML Express Integrated Graphics Controller (rev 03) Subsystem: ASUSTeK Computer Inc. Device 1252 00:1b.0 Audio device: Intel Corporation NM10/ICH7 Family High Definition Audio Controller (rev 02) Subsystem: ASUSTeK Computer Inc. Device 1297 Kernel driver in use: snd_hda_intel Kernel modules: snd-hda-intel 00:1c.0 PCI bridge: Intel Corporation NM10/ICH7 Family PCI Express Port 1 (rev 02) Kernel driver in use: pcieport Kernel modules: shpchp 00:1c.1 PCI bridge: Intel Corporation NM10/ICH7 Family PCI Express Port 2 (rev 02) Kernel driver in use: pcieport Kernel modules: shpchp 00:1d.0 USB controller: Intel Corporation NM10/ICH7 Family USB UHCI Controller #1 (rev 02) Subsystem: ASUSTeK Computer Inc. Device 1297 Kernel driver in use: uhci_hcd 00:1d.1 USB controller: Intel Corporation NM10/ICH7 Family USB UHCI Controller #2 (rev 02) Subsystem: ASUSTeK Computer Inc. Device 1297 Kernel driver in use: uhci_hcd 00:1d.2 USB controller: Intel Corporation NM10/ICH7 Family USB UHCI Controller #3 (rev 02) Subsystem: ASUSTeK Computer Inc. Device 1297 Kernel driver in use: uhci_hcd 00:1d.3 USB controller: Intel Corporation NM10/ICH7 Family USB UHCI Controller #4 (rev 02) Subsystem: ASUSTeK Computer Inc. Device 1297 Kernel driver in use: uhci_hcd 00:1d.7 USB controller: Intel Corporation NM10/ICH7 Family USB2 EHCI Controller (rev 02) Subsystem: ASUSTeK Computer Inc. Device 1297 Kernel driver in use: ehci_hcd 00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev e2) 00:1f.0 ISA bridge: Intel Corporation 82801GBM (ICH7-M) LPC Interface Bridge (rev 02) Subsystem: ASUSTeK Computer Inc. Device 1297 Kernel modules: leds-ss4200, iTCO_wdt, intel-rng 00:1f.1 IDE interface: Intel Corporation 82801G (ICH7 Family) IDE Controller (rev 02) Subsystem: ASUSTeK Computer Inc. Device 1297 Kernel driver in use: ata_piix 00:1f.3 SMBus: Intel Corporation NM10/ICH7 Family SMBus Controller (rev 02) Subsystem: ASUSTeK Computer Inc. Device 1297 Kernel modules: i2c-i801 02:00.0 Network controller: Intel Corporation PRO/Wireless 3945ABG [Golan] Network Connection (rev 02) Subsystem: Intel Corporation PRO/Wireless 3945ABG Network Connection Kernel driver in use: iwl3945 Kernel modules: iwl3945 03:01.0 CardBus bridge: Ricoh Co Ltd RL5c476 II (rev b3) Subsystem: ASUSTeK Computer Inc. Device 1297 Kernel driver in use: yenta_cardbus Kernel modules: yenta_socket 03:01.1 FireWire (IEEE 1394): Ricoh Co Ltd R5C552 IEEE 1394 Controller (rev 08) Subsystem: ASUSTeK Computer Inc. Device 1297 Kernel driver in use: firewire_ohci Kernel modules: firewire-ohci 03:01.2 SD Host controller: Ricoh Co Ltd R5C822 SD/SDIO/MMC/MS/MSPro Host Adapter (rev 17) Subsystem: ASUSTeK Computer Inc. Device 1297 Kernel driver in use: sdhci-pci Kernel modules: sdhci-pci 03:01.3 System peripheral: Ricoh Co Ltd R5C592 Memory Stick Bus Host Adapter (rev 08) Subsystem: ASUSTeK Computer Inc. Device 1297 Kernel driver in use: r592 Kernel modules: r592 03:07.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8169 PCI Gigabit Ethernet Controller (rev 10) Subsystem: ASUSTeK Computer Inc. Device 11e5 Kernel driver in use: r8169 Kernel modules: r8169 doug@ubuntu:/sam$ Things I have tried: sudo start network-manager: no help gksudo gedit /etc/network/interfaces changed line to iface eth0 inet dhcp: no help gksudo gedit /etc/NetworkManager/NetworkManager.conf, I changed managed=false to managed=true. Then sudo service network-manager restart: no help: network is unreachable sudo pkill -9 NetworkManager: no help gksudo gedit /etc/resolve.conf added line nameseriver 8.8.8.8: no help I know very little about networking; to date this has simply worked. Thanks for your help! :- Doug.

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• Web Browser Control &ndash; Specifying the IE Version

  - by Rick Strahl

  I use the Internet Explorer Web Browser Control in a lot of my applications to display document type layout. HTML happens to be one of the most common document formats and displaying data in this format – even in desktop applications, is often way easier than using normal desktop technologies. One issue the Web Browser Control has that it’s perpetually stuck in IE 7 rendering mode by default. Even though IE 8 and now 9 have significantly upgraded the IE rendering engine to be more CSS and HTML compliant by default the Web Browser control will have none of it. IE 9 in particular – with its much improved CSS support and basic HTML 5 support is a big improvement and even though the IE control uses some of IE’s internal rendering technology it’s still stuck in the old IE 7 rendering by default. This applies whether you’re using the Web Browser control in a WPF application, a WinForms app, a FoxPro or VB classic application using the ActiveX control. Behind the scenes all these UI platforms use the COM interfaces and so you’re stuck by those same rules. Rendering Challenged To see what I’m talking about here are two screen shots rendering an HTML 5 doctype page that includes some CSS 3 functionality – rounded corners and border shadows - from an earlier post. One uses IE 9 as a standalone browser, and one uses a simple WPF form that includes the Web Browser control. IE 9 Browser:   Web Browser control in a WPF form: The IE 9 page displays this HTML correctly – you see the rounded corners and shadow displayed. Obviously the latter rendering using the Web Browser control in a WPF application is a bit lacking. Not only are the new CSS features missing but the page also renders in Internet Explorer’s quirks mode so all the margins, padding etc. behave differently by default, even though there’s a CSS reset applied on this page. If you’re building an application that intends to use the Web Browser control for a live preview of some HTML this is clearly undesirable. Feature Delegation via Registry Hacks Fortunately starting with Internet Explore 8 and later there’s a fix for this problem via a registry setting. You can specify a registry key to specify which rendering mode and version of IE should be used by that application. These are not global mind you – they have to be enabled for each application individually. There are two different sets of keys for 32 bit and 64 bit applications. 32 bit: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\MAIN\FeatureControl\FEATURE_BROWSER_EMULATION Value Key: yourapplication.exe 64 bit: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Internet Explorer\MAIN\FeatureControl\FEATURE_BROWSER_EMULATION Value Key: yourapplication.exe The value to set this key to is (taken from MSDN here) as decimal values: 9999 (0x270F) Internet Explorer 9. Webpages are displayed in IE9 Standards mode, regardless of the !DOCTYPE directive. 9000 (0x2328) Internet Explorer 9. Webpages containing standards-based !DOCTYPE directives are displayed in IE9 mode. 8888 (0x22B8) Webpages are displayed in IE8 Standards mode, regardless of the !DOCTYPE directive. 8000 (0x1F40) Webpages containing standards-based !DOCTYPE directives are displayed in IE8 mode. 7000 (0x1B58) Webpages containing standards-based !DOCTYPE directives are displayed in IE7 Standards mode.   The added key looks something like this in the Registry Editor: With this in place my Html Html Help Builder application which has wwhelp.exe as its main executable now works with HTML 5 and CSS 3 documents in the same way that Internet Explorer 9 does. Incidentally I accidentally added an ‘empty’ DWORD value of 0 to my EXE name and that worked as well giving me IE 9 rendering. Although not documented I suspect 0 (or an invalid value) will default to the installed browser. Don’t have a good way to test this but if somebody could try this with IE 8 installed that would be great: What happens when setting 9000 with IE 8 installed? What happens when setting 0 with IE 8 installed? Don’t forget to add Keys for Host Environments If you’re developing your application in Visual Studio and you run the debugger you may find that your application is still not rendering right, but if you run the actual generated EXE from Explorer or the OS command prompt it works. That’s because when you run the debugger in Visual Studio it wraps your application into a debugging host container. For this reason you might want to also add another registry key for yourapp.vshost.exe on your development machine. If you’re developing in Visual FoxPro make sure you add a key for vfp9.exe to see the rendering adjustments in the Visual FoxPro development environment. Cleaner HTML - no more HTML mangling! There are a number of additional benefits to setting up rendering of the Web Browser control to the IE 9 engine (or even the IE 8 engine) beyond the obvious rendering functionality. IE 9 actually returns your HTML in something that resembles the original HTML formatting, as opposed to the IE 7 default format which mangled the original HTML content. If you do the following in the WPF application: private void button2_Click(object sender, RoutedEventArgs e) { dynamic doc = this.webBrowser.Document; MessageBox.Show(doc.body.outerHtml); } you get different output depending on the rendering mode active. With the default IE 7 rendering you get: <BODY><DIV> <H1>Rounded Corners and Shadows - Creating Dialogs in CSS</H1> <DIV class=toolbarcontainer><A class=hoverbutton href="./"><IMG src="../../css/images/home.gif"> Home</A> <A class=hoverbutton href="RoundedCornersAndShadows.htm"><IMG src="../../css/images/refresh.gif"> Refresh</A> </DIV> <DIV class=containercontent> <FIELDSET><LEGEND>Plain Box</LEGEND><!-- Simple Box with rounded corners and shadow --> <DIV style="BORDER-BOTTOM: steelblue 2px solid; BORDER-LEFT: steelblue 2px solid; WIDTH: 550px; BORDER-TOP: steelblue 2px solid; BORDER-RIGHT: steelblue 2px solid" class="roundbox boxshadow"> <DIV style="BACKGROUND: khaki" class="boxcontenttext roundbox">Simple Rounded Corner Box. </DIV></DIV></FIELDSET> <FIELDSET><LEGEND>Box with Header</LEGEND> <DIV style="BORDER-BOTTOM: steelblue 2px solid; BORDER-LEFT: steelblue 2px solid; WIDTH: 550px; BORDER-TOP: steelblue 2px solid; BORDER-RIGHT: steelblue 2px solid" class="roundbox boxshadow"> <DIV class="gridheaderleft roundbox-top">Box with a Header</DIV> <DIV style="BACKGROUND: khaki" class="boxcontenttext roundbox-bottom">Simple Rounded Corner Box. </DIV></DIV></FIELDSET> <FIELDSET><LEGEND>Dialog Style Window</LEGEND> <DIV style="POSITION: relative; WIDTH: 450px" id=divDialog class="dialog boxshadow" jQuery16107208195684204002="2"> <DIV style="POSITION: relative" class=dialog-header> <DIV class=closebox></DIV>User Sign-in <DIV class=closebox jQuery16107208195684204002="3"></DIV></DIV> <DIV class=descriptionheader>This dialog is draggable and closable</DIV> <DIV class=dialog-content><LABEL>Username:</LABEL> <INPUT name=txtUsername value=" "> <LABEL>Password</LABEL> <INPUT name=txtPassword value=" "> <HR> <INPUT id=btnLogin value=Login type=button> </DIV> <DIV class=dialog-statusbar>Ready</DIV></DIV></FIELDSET> </DIV> <SCRIPT type=text/javascript>     $(document).ready(function () {         $("#divDialog")             .draggable({ handle: ".dialog-header" })             .closable({ handle: ".dialog-header",                 closeHandler: function () {                     alert("Window about to be closed.");                     return true;  // true closes - false leaves open                 }             });     }); </SCRIPT> </DIV></BODY> Now lest you think I’m out of my mind and create complete whacky HTML rooted in the last century, here’s the IE 9 rendering mode output which looks a heck of a lot cleaner and a lot closer to my original HTML of the page I’m accessing: <body> <div>         <h1>Rounded Corners and Shadows - Creating Dialogs in CSS</h1>     <div class="toolbarcontainer">         <a class="hoverbutton" href="./"> <img src="../../css/images/home.gif"> Home</a>         <a class="hoverbutton" href="RoundedCornersAndShadows.htm"> <img src="../../css/images/refresh.gif"> Refresh</a>     </div>         <div class="containercontent">     <fieldset>         <legend>Plain Box</legend>                <!-- Simple Box with rounded corners and shadow -->             <div style="border: 2px solid steelblue; width: 550px;" class="roundbox boxshadow">                              <div style="background: khaki;" class="boxcontenttext roundbox">                     Simple Rounded Corner Box.                 </div>             </div>     </fieldset>     <fieldset>         <legend>Box with Header</legend>         <div style="border: 2px solid steelblue; width: 550px;" class="roundbox boxshadow">                          <div class="gridheaderleft roundbox-top">Box with a Header</div>             <div style="background: khaki;" class="boxcontenttext roundbox-bottom">                 Simple Rounded Corner Box.             </div>         </div>     </fieldset>       <fieldset>         <legend>Dialog Style Window</legend>         <div style="width: 450px; position: relative;" id="divDialog" class="dialog boxshadow">             <div style="position: relative;" class="dialog-header">                 <div class="closebox"></div>                 User Sign-in             <div class="closebox"></div></div>             <div class="descriptionheader">This dialog is draggable and closable</div>                    <div class="dialog-content">                             <label>Username:</label>                 <input name="txtUsername" value=" " type="text">                 <label>Password</label>                 <input name="txtPassword" value=" " type="text">                                 <hr/>                                 <input id="btnLogin" value="Login" type="button">                        </div>             <div class="dialog-statusbar">Ready</div>         </div>     </fieldset>     </div> <script type="text/javascript">     $(document).ready(function () {         $("#divDialog")             .draggable({ handle: ".dialog-header" })             .closable({ handle: ".dialog-header",                 closeHandler: function () {                     alert("Window about to be closed.");                     return true;  // true closes - false leaves open                 }             });     }); </script>        </div> </body> IOW, in IE9 rendering mode IE9 is much closer (but not identical) to the original HTML from the page on the Web that we’re reading from. As a side note: Unfortunately, the browser feature emulation can't be applied against the Html Help (CHM) Engine in Windows which uses the Web Browser control (or COM interfaces anyway) to render Html Help content. I tried setting up hh.exe which is the help viewer, to use IE 9 rendering but a help file generated with CSS3 features will simply show in IE 7 mode. Bummer - this would have been a nice quick fix to allow help content served from CHM files to look better. HTML Editing leaves HTML formatting intact In the same vane, if you do any inline HTML editing in the control by setting content to be editable, IE 9’s control does a much more reasonable job of creating usable and somewhat valid HTML. It also leaves the original content alone other than the text your are editing or adding. No longer is the HTML output stripped of excess spaces and reformatted in IEs format. So if I do: private void button3_Click(object sender, RoutedEventArgs e) { dynamic doc = this.webBrowser.Document; doc.body.contentEditable = true; } and then make some changes to the document by typing into it using IE 9 mode, the document formatting stays intact and only the affected content is modified. The created HTML is reasonably clean (although it does lack proper XHTML formatting for things like <br/> <hr/>). This is very different from IE 7 mode which mangled the HTML as soon as the page was loaded into the control. Any editing you did stripped out all white space and lost all of your existing XHTML formatting. In IE 9 mode at least *most* of your original formatting stays intact. This is huge! In Html Help Builder I have supported HTML editing for a long time but the HTML mangling by the Web Browser control made it very difficult to edit the HTML later. Previously IE would mangle the HTML by stripping out spaces, upper casing all tags and converting many XHTML safe tags to its HTML 3 tags. Now IE leaves most of my document alone while editing, and creates cleaner and more compliant markup (with exception of self-closing elements like BR/HR). The end result is that I now have HTML editing in place that's much cleaner and actually capable of being manually edited. Caveats, Caveats, Caveats It wouldn't be Internet Explorer if there weren't some major compatibility issues involved in using this various browser version interaction. The biggest thing I ran into is that there are odd differences in some of the COM interfaces and what they return. I specifically ran into a problem with the document.selection.createRange() function which with IE 7 compatibility returns an expected text range object. When running in IE 8 or IE 9 mode however. I could not retrieve a valid text range with this code where loEdit is the WebBrowser control: loRange = loEdit.document.selection.CreateRange() The loRange object returned (here in FoxPro) had a length property of 0 but none of the other properties of the TextRange or TextRangeCollection objects were available. I figured this was due to some changed security settings but even after elevating the Intranet Security Zone and mucking with the other browser feature flags pertaining to security I had no luck. In the end I relented and used a JavaScript function in my editor document that returns a selection range object: function getselectionrange() { var range = document.selection.createRange(); return range; } and call that JavaScript function from my host applications code: *** Use a function in the document to get around HTML Editing issues loRange = loEdit.document.parentWindow.getselectionrange(.f.) and that does work correctly. This wasn't a big deal as I'm already loading a support script file into the editor page so all I had to do is add the function to this existing script file. You can find out more how to call script code in the Web Browser control from a host application in a previous post of mine. IE 8 and 9 also clamp down the security environment a little more than the default IE 7 control, so there may be other issues you run into. Other than the createRange() problem above I haven't seen anything else that is breaking in my code so far though and that's encouraging at least since it uses a lot of HTML document manipulation for the custom editor I've created (and would love to replace - any PROFESSIONAL alternatives anybody?) Registry Key Installation for your Application It’s important to remember that this registry setting is made per application, so most likely this is something you want to set up with your installer. Also remember that 32 and 64 bit settings require separate settings in the registry so if you’re creating your installer you most likely will want to set both keys in the registry preemptively for your application. I use Tarma Installer for all of my application installs and in Tarma I configure registry keys for both and set a flag to only install the latter key group in the 64 bit version: Because this setting is application specific you have to do this for every application you install unfortunately, but this also means that you can safely configure this setting in the registry because it is after only applied to your application. Another problem with install based installation is version detection. If IE 8 is installed I’d want 8000 for the value, if IE 9 is installed I want 9000. I can do this easily in code but in the installer this is much more difficult. I don’t have a good solution for this at the moment, but given that the app works with IE 7 mode now, IE 9 mode is just a bonus for the moment. If IE 9 is not installed and 9000 is used the default rendering will remain in use.   It sure would be nice if we could specify the IE rendering mode as a property, but I suspect the ActiveX container has to know before it loads what actual version to load up and once loaded can only load a single version of IE. This would account for this annoying application level configuration… Summary The registry feature emulation has been available for quite some time, but I just found out about it today and started experimenting around with it. I’m stoked to see that this is available as I’d pretty much given up in ever seeing any better rendering in the Web Browser control. Now at least my apps can take advantage of newer HTML features. Now if we could only get better HTML Editing support somehow <snicker>… ah can’t have everything.© Rick Strahl, West Wind Technologies, 2005-2011Posted in .NET  FoxPro  Windows  

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• Silverlight for Windows Embedded tutorial (step 4)

  - by Valter Minute

  I’m back with my Silverlight for Windows Embedded tutorial. Sorry for the long delay between step 3 and step 4, the MVP summit and some work related issue prevented me from working on the tutorial during the last weeks. In our first,  second and third tutorial steps we implemented some very simple applications, just to understand the basic structure of a Silverlight for Windows Embedded application, learn how to handle events and how to operate on images. In this third step our sample application will be slightly more complicated, to introduce two new topics: list boxes and custom control. We will also learn how to create controls at runtime. I choose to explain those topics together and provide a sample a bit more complicated than usual just to start to give the feeling of how a “real” Silverlight for Windows Embedded application is organized. As usual we can start using Expression Blend to define our main page. In this case we will have a listbox and a textblock. Here’s the XAML code: <UserControl xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" x:Class="ListDemo.Page" Width="640" Height="480" x:Name="ListPage" xmlns:ListDemo="clr-namespace:ListDemo">   <Grid x:Name="LayoutRoot" Background="White"> <ListBox Margin="19,57,19,66" x:Name="FileList" SelectionChanged="Filelist_SelectionChanged"/> <TextBlock Height="35" Margin="19,8,19,0" VerticalAlignment="Top" TextWrapping="Wrap" x:Name="CurrentDir" Text="TextBlock" FontSize="20"/> </Grid> </UserControl> In our listbox we will load a list of directories, starting from the filesystem root (there are no drives in Windows CE, the filesystem has a single root named “\”). When the user clicks on an item inside the list, the corresponding directory path will be displayed in the TextBlock object and the subdirectories of the selected branch will be shown inside the list. As you can see we declared an event handler for the SelectionChanged event of our listbox. We also used a different font size for the TextBlock, to make it more readable. XAML and Expression Blend allow you to customize your UI pretty heavily, experiment with the tools and discover how you can completely change the aspect of your application without changing a single line of code! Inside our ListBox we want to insert the directory presenting a nice icon and their name, just like you are used to see them inside Windows 7 file explorer, for example. To get this we will define a user control. This is a custom object that will behave like “regular” Silverlight for Windows Embedded objects inside our application. First of all we have to define the look of our custom control, named DirectoryItem, using XAML: <UserControl xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" mc:Ignorable="d" x:Class="ListDemo.DirectoryItem" Width="500" Height="80">   <StackPanel x:Name="LayoutRoot" Orientation="Horizontal"> <Canvas Width="31.6667" Height="45.9583" Margin="10,10,10,10" RenderTransformOrigin="0.5,0.5"> <Canvas.RenderTransform> <TransformGroup> <ScaleTransform/> <SkewTransform/> <RotateTransform Angle="-31.27"/> <TranslateTransform/> </TransformGroup> </Canvas.RenderTransform> <Rectangle Width="31.6667" Height="45.8414" Canvas.Left="0" Canvas.Top="0.116943" Stretch="Fill"> <Rectangle.Fill> <LinearGradientBrush StartPoint="0.142631,0.75344" EndPoint="1.01886,0.75344"> <LinearGradientBrush.RelativeTransform> <TransformGroup> <SkewTransform CenterX="0.142631" CenterY="0.75344" AngleX="19.3128" AngleY="0"/> <RotateTransform CenterX="0.142631" CenterY="0.75344" Angle="-35.3436"/> </TransformGroup> </LinearGradientBrush.RelativeTransform> <LinearGradientBrush.GradientStops> <GradientStop Color="#FF7B6802" Offset="0"/> <GradientStop Color="#FFF3D42C" Offset="1"/> </LinearGradientBrush.GradientStops> </LinearGradientBrush> </Rectangle.Fill> </Rectangle> <Rectangle Width="29.8441" Height="43.1517" Canvas.Left="0.569519" Canvas.Top="1.05249" Stretch="Fill"> <Rectangle.Fill> <LinearGradientBrush StartPoint="0.142632,0.753441" EndPoint="1.01886,0.753441"> <LinearGradientBrush.RelativeTransform> <TransformGroup> <SkewTransform CenterX="0.142632" CenterY="0.753441" AngleX="19.3127" AngleY="0"/> <RotateTransform CenterX="0.142632" CenterY="0.753441" Angle="-35.3437"/> </TransformGroup> </LinearGradientBrush.RelativeTransform> <LinearGradientBrush.GradientStops> <GradientStop Color="#FFCDCDCD" Offset="0.0833333"/> <GradientStop Color="#FFFFFFFF" Offset="1"/> </LinearGradientBrush.GradientStops> </LinearGradientBrush> </Rectangle.Fill> </Rectangle> <Rectangle Width="29.8441" Height="43.1517" Canvas.Left="0.455627" Canvas.Top="2.28036" Stretch="Fill"> <Rectangle.Fill> <LinearGradientBrush StartPoint="0.142631,0.75344" EndPoint="1.01886,0.75344"> <LinearGradientBrush.RelativeTransform> <TransformGroup> <SkewTransform CenterX="0.142631" CenterY="0.75344" AngleX="19.3128" AngleY="0"/> <RotateTransform CenterX="0.142631" CenterY="0.75344" Angle="-35.3436"/> </TransformGroup> </LinearGradientBrush.RelativeTransform> <LinearGradientBrush.GradientStops> <GradientStop Color="#FFCDCDCD" Offset="0.0833333"/> <GradientStop Color="#FFFFFFFF" Offset="1"/> </LinearGradientBrush.GradientStops> </LinearGradientBrush> </Rectangle.Fill> </Rectangle> <Rectangle Width="29.8441" Height="43.1517" Canvas.Left="0.455627" Canvas.Top="1.34485" Stretch="Fill"> <Rectangle.Fill> <LinearGradientBrush StartPoint="0.142631,0.75344" EndPoint="1.01886,0.75344"> <LinearGradientBrush.RelativeTransform> <TransformGroup> <SkewTransform CenterX="0.142631" CenterY="0.75344" AngleX="19.3128" AngleY="0"/> <RotateTransform CenterX="0.142631" CenterY="0.75344" Angle="-35.3436"/> </TransformGroup> </LinearGradientBrush.RelativeTransform> <LinearGradientBrush.GradientStops> <GradientStop Color="#FFCDCDCD" Offset="0.0833333"/> <GradientStop Color="#FFFFFFFF" Offset="1"/> </LinearGradientBrush.GradientStops> </LinearGradientBrush> </Rectangle.Fill> </Rectangle> <Rectangle Width="26.4269" Height="45.8414" Canvas.Left="0.227798" Canvas.Top="0" Stretch="Fill"> <Rectangle.Fill> <LinearGradientBrush StartPoint="0.142631,0.75344" EndPoint="1.01886,0.75344"> <LinearGradientBrush.RelativeTransform> <TransformGroup> <SkewTransform CenterX="0.142631" CenterY="0.75344" AngleX="19.3127" AngleY="0"/> <RotateTransform CenterX="0.142631" CenterY="0.75344" Angle="-35.3436"/> </TransformGroup> </LinearGradientBrush.RelativeTransform> <LinearGradientBrush.GradientStops> <GradientStop Color="#FF7B6802" Offset="0"/> <GradientStop Color="#FFF3D42C" Offset="1"/> </LinearGradientBrush.GradientStops> </LinearGradientBrush> </Rectangle.Fill> </Rectangle> <Rectangle Width="1.25301" Height="45.8414" Canvas.Left="1.70862" Canvas.Top="0.116943" Stretch="Fill" Fill="#FFEBFF07"/> </Canvas> <TextBlock Height="80" x:Name="Name" Width="448" TextWrapping="Wrap" VerticalAlignment="Center" FontSize="24" Text="Directory"/> </StackPanel> </UserControl> As you can see, this XAML contains many graphic elements. Those elements are used to design the folder icon. The original drawing has been designed in Expression Design and then exported as XAML. In Silverlight for Windows Embedded you can use vector images. This means that your images will look good even when scaled or rotated. In our DirectoryItem custom control we have a TextBlock named Name, that will be used to display….(suspense)…. the directory name (I’m too lazy to invent fancy names for controls, and using “boring” intuitive names will make code more readable, I hope!). Now that we have some XAML code, we may execute XAML2CPP to generate part of the aplication code for us. We should then add references to our XAML2CPP generated resource file and include in our code and add a reference to the XAML runtime library to our sources file (you can follow the instruction of the first tutorial step to do that), To generate the code used in this tutorial you need XAML2CPP ver 1.0.1.0, that is downloadable here: http://geekswithblogs.net/WindowsEmbeddedCookbook/archive/2010/03/08/xaml2cpp-1.0.1.0.aspx We can now create our usual simple Win32 application inside Platform Builder, using the same step described in the first chapter of this tutorial (http://geekswithblogs.net/WindowsEmbeddedCookbook/archive/2009/10/01/silverlight-for-embedded-tutorial.aspx). We can declare a class for our main page, deriving it from the template that XAML2CPP generated for us: class ListPage : public TListPage<ListPage> { ... } We will see the ListPage class code in a short time, but before we will see the code of our DirectoryItem user control. This object will be used to populate our list, one item for each directory. To declare a user control things are a bit more complicated (but also in this case XAML2CPP will write most of the “boilerplate” code for use. To interact with a user control you should declare an interface. An interface defines the functions of a user control that can be called inside the application code. Our custom control is currently quite simple and we just need some member functions to store and retrieve a full pathname inside our control. The control will display just the last part of the path inside the control. An interface is declared as a C++ class that has only abstract virtual members. It should also have an UUID associated with it. UUID means Universal Unique IDentifier and it’s a 128 bit number that will identify our interface without the need of specifying its fully qualified name. UUIDs are used to identify COM interfaces and, as we discovered in chapter one, Silverlight for Windows Embedded is based on COM or, at least, provides a COM-like Application Programming Interface (API). Here’s the declaration of the DirectoryItem interface: class __declspec(novtable,uuid("{D38C66E5-2725-4111-B422-D75B32AA8702}")) IDirectoryItem : public IXRCustomUserControl { public:   virtual HRESULT SetFullPath(BSTR fullpath) = 0; virtual HRESULT GetFullPath(BSTR* retval) = 0; }; The interface is derived from IXRCustomControl, this will allow us to add our object to a XAML tree. It declares the two functions needed to set and get the full path, but don’t implement them. Implementation will be done inside the control class. The interface only defines the functions of our control class that are accessible from the outside. It’s a sort of “contract” between our control and the applications that will use it. We must support what’s inside the contract and the application code should know nothing else about our own control. To reference our interface we will use the UUID, to make code more readable we can declare a #define in this way: #define IID_IDirectoryItem __uuidof(IDirectoryItem) Silverlight for Windows Embedded objects (like COM objects) use a reference counting mechanism to handle object destruction. Every time you store a pointer to an object you should call its AddRef function and every time you no longer need that pointer you should call Release. The object keeps an internal counter, incremented for each AddRef and decremented on Release. When the counter reaches 0, the object is destroyed. Managing reference counting in our code can be quite complicated and, since we are lazy (I am, at least!), we will use a great feature of Silverlight for Windows Embedded: smart pointers.A smart pointer can be connected to a Silverlight for Windows Embedded object and manages its reference counting. To declare a smart pointer we must use the XRPtr template: typedef XRPtr<IDirectoryItem> IDirectoryItemPtr; Now that we have defined our interface, it’s time to implement our user control class. XAML2CPP has implemented a class for us, and we have only to derive our class from it, defining the main class and interface of our new custom control: class DirectoryItem : public DirectoryItemUserControlRegister<DirectoryItem,IDirectoryItem> { ... } XAML2CPP has generated some code for us to support the user control, we don’t have to mind too much about that code, since it will be generated (or written by hand, if you like) always in the same way, for every user control. But knowing how does this works “under the hood” is still useful to understand the architecture of Silverlight for Windows Embedded. Our base class declaration is a bit more complex than the one we used for a simple page in the previous chapters: template <class A,class B> class DirectoryItemUserControlRegister : public XRCustomUserControlImpl<A,B>,public TDirectoryItem<A,XAML2CPPUserControl> { ... } This class derives from the XAML2CPP generated template class, like the ListPage class, but it uses XAML2CPPUserControl for the implementation of some features. This class shares the same ancestor of XAML2CPPPage (base class for “regular” XAML pages), XAML2CPPBase, implements binding of member variables and event handlers but, instead of loading and creating its own XAML tree, it attaches to an existing one. The XAML tree (and UI) of our custom control is created and loaded by the XRCustomUserControlImpl class. This class is part of the Silverlight for Windows Embedded framework and implements most of the functions needed to build-up a custom control in Silverlight (the guys that developed Silverlight for Windows Embedded seem to care about lazy programmers!). We have just to initialize it, providing our class (DirectoryItem) and interface (IDirectoryItem). Our user control class has also a static member: protected:   static HINSTANCE hInstance; This is used to store the HINSTANCE of the modules that contain our user control class. I don’t like this implementation, but I can’t find a better one, so if somebody has good ideas about how to handle the HINSTANCE object, I’ll be happy to hear suggestions! It also implements two static members required by XRCustomUserControlImpl. The first one is used to load the XAML UI of our custom control: static HRESULT GetXamlSource(XRXamlSource* pXamlSource) { pXamlSource->SetResource(hInstance,TEXT("XAML"),IDR_XAML_DirectoryItem); return S_OK; }   It initializes a XRXamlSource object, connecting it to the XAML resource that XAML2CPP has included in our resource script. The other method is used to register our custom control, allowing Silverlight for Windows Embedded to create it when it load some XAML or when an application creates a new control at runtime (more about this later): static HRESULT Register() { return XRCustomUserControlImpl<A,B>::Register(__uuidof(B), L"DirectoryItem", L"clr-namespace:DirectoryItemNamespace"); } To register our control we should provide its interface UUID, the name of the corresponding element in the XAML tree and its current namespace (namespaces compatible with Silverlight must use the “clr-namespace” prefix. We may also register additional properties for our objects, allowing them to be loaded and saved inside XAML. In this case we have no permanent properties and the Register method will just register our control. An additional static method is implemented to allow easy registration of our custom control inside our application WinMain function: static HRESULT RegisterUserControl(HINSTANCE hInstance) { DirectoryItemUserControlRegister::hInstance=hInstance; return DirectoryItemUserControlRegister<A,B>::Register(); } Now our control is registered and we will be able to create it using the Silverlight for Windows Embedded runtime functions. But we need to bind our members and event handlers to have them available like we are used to do for other XAML2CPP generated objects. To bind events and members we need to implement the On_Loaded function: virtual HRESULT OnLoaded(__in IXRDependencyObject* pRoot) { HRESULT retcode; IXRApplicationPtr app; if (FAILED(retcode=GetXRApplicationInstance(&app))) return retcode; return ((A*)this)->Init(pRoot,hInstance,app); } This function will call the XAML2CPPUserControl::Init member that will connect the “root” member with the XAML sub tree that has been created for our control and then calls BindObjects and BindEvents to bind members and events to our code. Now we can go back to our application code (the code that you’ll have to actually write) to see the contents of our DirectoryItem class: class DirectoryItem : public DirectoryItemUserControlRegister<DirectoryItem,IDirectoryItem> { protected:   WCHAR fullpath[_MAX_PATH+1];   public:   DirectoryItem() { *fullpath=0; }   virtual HRESULT SetFullPath(BSTR fullpath) { wcscpy_s(this->fullpath,fullpath);   WCHAR* p=fullpath;   for(WCHAR*q=wcsstr(p,L"\\");q;p=q+1,q=wcsstr(p,L"\\")) ;   Name->SetText(p); return S_OK; }   virtual HRESULT GetFullPath(BSTR* retval) { *retval=SysAllocString(fullpath); return S_OK; } }; It’s pretty easy and contains a fullpath member (used to store that path of the directory connected with the user control) and the implementation of the two interface members that can be used to set and retrieve the path. The SetFullPath member parses the full path and displays just the last branch directory name inside the “Name” TextBlock object. As you can see, implementing a user control in Silverlight for Windows Embedded is not too complex and using XAML also for the UI of the control allows us to re-use the same mechanisms that we learnt and used in the previous steps of our tutorial. Now let’s see how the main page is managed by the ListPage class. class ListPage : public TListPage<ListPage> { protected:   // current path TCHAR curpath[_MAX_PATH+1]; It has a member named “curpath” that is used to store the current directory. It’s initialized inside the constructor: ListPage() { *curpath=0; } And it’s value is displayed inside the “CurrentDir” TextBlock inside the initialization function: virtual HRESULT Init(HINSTANCE hInstance,IXRApplication* app) { HRESULT retcode;   if (FAILED(retcode=TListPage<ListPage>::Init(hInstance,app))) return retcode;   CurrentDir->SetText(L"\\"); return S_OK; } The FillFileList function is used to enumerate subdirectories of the current dir and add entries for each one inside the list box that fills most of the client area of our main page: HRESULT FillFileList() { HRESULT retcode; IXRItemCollectionPtr items; IXRApplicationPtr app;   if (FAILED(retcode=GetXRApplicationInstance(&app))) return retcode; // retrieves the items contained in the listbox if (FAILED(retcode=FileList->GetItems(&items))) return retcode;   // clears the list if (FAILED(retcode=items->Clear())) return retcode;   // enumerates files and directory in the current path WCHAR filemask[_MAX_PATH+1];   wcscpy_s(filemask,curpath); wcscat_s(filemask,L"\\*.*");   WIN32_FIND_DATA finddata; HANDLE findhandle;   findhandle=FindFirstFile(filemask,&finddata);   // the directory is empty? if (findhandle==INVALID_HANDLE_VALUE) return S_OK;   do { if (finddata.dwFileAttributes&=FILE_ATTRIBUTE_DIRECTORY) { IXRListBoxItemPtr listboxitem;   // add a new item to the listbox if (FAILED(retcode=app->CreateObject(IID_IXRListBoxItem,&listboxitem))) { FindClose(findhandle); return retcode; }   if (FAILED(retcode=items->Add(listboxitem,NULL))) { FindClose(findhandle); return retcode; }   IDirectoryItemPtr directoryitem;   if (FAILED(retcode=app->CreateObject(IID_IDirectoryItem,&directoryitem))) { FindClose(findhandle); return retcode; }   WCHAR fullpath[_MAX_PATH+1];   wcscpy_s(fullpath,curpath); wcscat_s(fullpath,L"\\"); wcscat_s(fullpath,finddata.cFileName);   if (FAILED(retcode=directoryitem->SetFullPath(fullpath))) { FindClose(findhandle); return retcode; }   XAML2CPPXRValue value((IXRDependencyObject*)directoryitem);   if (FAILED(retcode=listboxitem->SetContent(&value))) { FindClose(findhandle); return retcode; } } } while (FindNextFile(findhandle,&finddata));   FindClose(findhandle); return S_OK; } This functions retrieve a pointer to the collection of the items contained in the directory listbox. The IXRItemCollection interface is used by listboxes and comboboxes and allow you to clear the list (using Clear(), as our function does at the beginning) and change its contents by adding and removing elements. This function uses the FindFirstFile/FindNextFile functions to enumerate all the objects inside our current directory and for each subdirectory creates a IXRListBoxItem object. You can insert any kind of control inside a list box, you don’t need a IXRListBoxItem, but using it will allow you to handle the selected state of an item, highlighting it inside the list. The function creates a list box item using the CreateObject function of XRApplication. The same function is then used to create an instance of our custom control. The function returns a pointer to the control IDirectoryItem interface and we can use it to store the directory full path inside the object and add it as content of the IXRListBox item object, adding it to the listbox contents. The listbox generates an event (SelectionChanged) each time the user clicks on one of the items contained in the listbox. We implement an event handler for that event and use it to change our current directory and repopulate the listbox. The current directory full path will be displayed in the TextBlock: HRESULT Filelist_SelectionChanged(IXRDependencyObject* source,XRSelectionChangedEventArgs* args) { HRESULT retcode;   IXRListBoxItemPtr listboxitem;   if (!args->pAddedItem) return S_OK;   if (FAILED(retcode=args->pAddedItem->QueryInterface(IID_IXRListBoxItem,(void**)&listboxitem))) return retcode;   XRValue content; if (FAILED(retcode=listboxitem->GetContent(&content))) return retcode;   if (content.vType!=VTYPE_OBJECT) return E_FAIL;   IDirectoryItemPtr directoryitem;   if (FAILED(retcode=content.pObjectVal->QueryInterface(IID_IDirectoryItem,(void**)&directoryitem))) return retcode;   content.pObjectVal->Release(); content.pObjectVal=NULL;   BSTR fullpath=NULL;   if (FAILED(retcode=directoryitem->GetFullPath(&fullpath))) return retcode;   CurrentDir->SetText(fullpath);   wcscpy_s(curpath,fullpath); FillFileList(); SysFreeString(fullpath);     return S_OK; } }; The function uses the pAddedItem member of the XRSelectionChangedEventArgs object to retrieve the currently selected item, converts it to a IXRListBoxItem interface using QueryInterface, and then retrives its contents (IDirectoryItem object). Using the GetFullPath method we can get the full path of our selected directory and assing it to the curdir member. A call to FillFileList will update the listbox contents, displaying the list of subdirectories of the selected folder. To build our sample we just need to add code to our WinMain function: int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPTSTR lpCmdLine, int nCmdShow) { if (!XamlRuntimeInitialize()) return -1;   HRESULT retcode;   IXRApplicationPtr app; if (FAILED(retcode=GetXRApplicationInstance(&app))) return -1;   if (FAILED(retcode=DirectoryItem::RegisterUserControl(hInstance))) return retcode;   ListPage page;   if (FAILED(page.Init(hInstance,app))) return -1;   page.FillFileList();   UINT exitcode;   if (FAILED(page.GetVisualHost()->StartDialog(&exitcode))) return -1;   return 0; } This code is very similar to the one of the WinMains of our previous samples. The main differences are that we register our custom control (you should do that as soon as you have initialized the XAML runtime) and call FillFileList after the initialization of our ListPage object to load the contents of the root folder of our device inside the listbox. As usual you can download the full sample source code from here: http://cid-9b7b0aefe3514dc5.skydrive.live.com/self.aspx/.Public/ListBoxTest.zip

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• Quick guide to Oracle IRM 11g: Classification design

  - by Simon Thorpe

  Quick guide to Oracle IRM 11g indexThis is the final article in the quick guide to Oracle IRM. If you've followed everything prior you will now have a fully functional and tested Information Rights Management service. It doesn't matter if you've been following the 10g or 11g guide as this next article is common to both. ContentsWhy this is the most important part... Understanding the classification and standard rights model Identifying business use cases Creating an effective IRM classification modelOne single classification across the entire businessA context for each and every possible granular use caseWhat makes a good context? Deciding on the use of roles in the context Reviewing the features and security for context roles Summary Why this is the most important part...Now the real work begins, installing and getting an IRM system running is as simple as following instructions. However to actually have an IRM technology easily protecting your most sensitive information without interfering with your users existing daily work flows and be able to scale IRM across the entire business, requires thought into how confidential documents are created, used and distributed. This article is going to give you the information you need to ask the business the right questions so that you can deploy your IRM service successfully. The IRM team here at Oracle have over 10 years of experience in helping customers and it is important you understand the following to be successful in securing access to your most confidential information. Whatever you are trying to secure, be it mergers and acquisitions information, engineering intellectual property, health care documentation or financial reports. No matter what type of user is going to access the information, be they employees, contractors or customers, there are common goals you are always trying to achieve.Securing the content at the earliest point possible and do it automatically. Removing the dependency on the user to decide to secure the content reduces the risk of mistakes significantly and therefore results a more secure deployment. K.I.S.S. (Keep It Simple Stupid) Reduce complexity in the rights/classification model. Oracle IRM lets you make changes to access to documents even after they are secured which allows you to start with a simple model and then introduce complexity once you've understood how the technology is going to be used in the business. After an initial learning period you can review your implementation and start to make informed decisions based on user feedback and administration experience. Clearly communicate to the user, when appropriate, any changes to their existing work practice. You must make every effort to make the transition to sealed content as simple as possible. For external users you must help them understand why you are securing the documents and inform them the value of the technology to both your business and them. Before getting into the detail, I must pay homage to Martin White, Vice President of client services in SealedMedia, the company Oracle acquired and who created Oracle IRM. In the SealedMedia years Martin was involved with every single customer and was key to the design of certain aspects of the IRM technology, specifically the context model we will be discussing here. Listening carefully to customers and understanding the flexibility of the IRM technology, Martin taught me all the skills of helping customers build scalable, effective and simple to use IRM deployments. No matter how well the engineering department designed the software, badly designed and poorly executed projects can result in difficult to use and manage, and ultimately insecure solutions. The advice and information that follows was born with Martin and he's still delivering IRM consulting with customers and can be found at www.thinkers.co.uk. It is from Martin and others that Oracle not only has the most advanced, scalable and usable document security solution on the market, but Oracle and their partners have the most experience in delivering successful document security solutions. Understanding the classification and standard rights model The goal of any successful IRM deployment is to balance the increase in security the technology brings without over complicating the way people use secured content and avoid a significant increase in administration and maintenance. With Oracle it is possible to automate the protection of content, deploy the desktop software transparently and use authentication methods such that users can open newly secured content initially unaware the document is any different to an insecure one. That is until of course they attempt to do something for which they don't have any rights, such as copy and paste to an insecure application or try and print. Central to achieving this objective is creating a classification model that is simple to understand and use but also provides the right level of complexity to meet the business needs. In Oracle IRM the term used for each classification is a "context". A context defines the relationship between.A group of related documents The people that use the documents The roles that these people perform The rights that these people need to perform their role The context is the key to the success of Oracle IRM. It provides the separation of the role and rights of a user from the content itself. Documents are sealed to contexts but none of the rights, user or group information is stored within the content itself. Sealing only places information about the location of the IRM server that sealed it, the context applied to the document and a few other pieces of metadata that pertain only to the document. This important separation of rights from content means that millions of documents can be secured against a single classification and a user needs only one right assigned to be able to access all documents. If you have followed all the previous articles in this guide, you will be ready to start defining contexts to which your sensitive information will be protected. But before you even start with IRM, you need to understand how your own business uses and creates sensitive documents and emails. Identifying business use cases Oracle is able to support multiple classification systems, but usually there is one single initial need for the technology which drives a deployment. This need might be to protect sensitive mergers and acquisitions information, engineering intellectual property, financial documents. For this and every subsequent use case you must understand how users create and work with documents, to who they are distributed and how the recipients should interact with them. A successful IRM deployment should start with one well identified use case (we go through some examples towards the end of this article) and then after letting this use case play out in the business, you learn how your users work with content, how well your communication to the business worked and if the classification system you deployed delivered the right balance. It is at this point you can start rolling the technology out further. Creating an effective IRM classification model Once you have selected the initial use case you will address with IRM, you need to design a classification model that defines the access to secured documents within the use case. In Oracle IRM there is an inbuilt classification system called the "context" model. In Oracle IRM 11g it is possible to extend the server to support any rights classification model, but the majority of users who are not using an application integration (such as Oracle IRM within Oracle Beehive) are likely to be starting out with the built in context model. Before looking at creating a classification system with IRM, it is worth reviewing some recognized standards and methods for creating and implementing security policy. A very useful set of documents are the ISO 17799 guidelines and the SANS security policy templates. First task is to create a context against which documents are to be secured. A context consists of a group of related documents (all top secret engineering research), a list of roles (contributors and readers) which define how users can access documents and a list of users (research engineers) who have been given a role allowing them to interact with sealed content. Before even creating the first context it is wise to decide on a philosophy which will dictate the level of granularity, the question is, where do you start? At a department level? By project? By technology? First consider the two ends of the spectrum... One single classification across the entire business Imagine that instead of having separate contexts, one for engineering intellectual property, one for your financial data, one for human resources personally identifiable information, you create one context for all documents across the entire business. Whilst you may have immediate objections, there are some significant benefits in thinking about considering this. Document security classification decisions are simple. You only have one context to chose from! User provisioning is simple, just make sure everyone has a role in the only context in the business. Administration is very low, if you assign rights to groups from the business user repository you probably never have to touch IRM administration again. There are however some obvious downsides to this model.All users in have access to all IRM secured content. So potentially a sales person could access sensitive mergers and acquisition documents, if they can get their hands on a copy that is. You cannot delegate control of different documents to different parts of the business, this may not satisfy your regulatory requirements for the separation and delegation of duties. Changing a users role affects every single document ever secured. Even though it is very unlikely a business would ever use one single context to secure all their sensitive information, thinking about this scenario raises one very important point. Just having one single context and securing all confidential documents to it, whilst incurring some of the problems detailed above, has one huge value. Once secured, IRM protected content can ONLY be accessed by authorized users. Just think of all the sensitive documents in your business today, imagine if you could ensure that only everyone you trust could open them. Even if an employee lost a laptop or someone accidentally sent an email to the wrong recipient, only the right people could open that file. A context for each and every possible granular use case Now let's think about the total opposite of a single context design. What if you created a context for each and every single defined business need and created multiple contexts within this for each level of granularity? Let's take a use case where we need to protect engineering intellectual property. Imagine we have 6 different engineering groups, and in each we have a research department, a design department and manufacturing. The company information security policy defines 3 levels of information sensitivity... restricted, confidential and top secret. Then let's say that each group and department needs to define access to information from both internal and external users. Finally add into the mix that they want to review the rights model for each context every financial quarter. This would result in a huge amount of contexts. For example, lets just look at the resulting contexts for one engineering group. Q1FY2010 Restricted Internal - Engineering Group 1 - Research Q1FY2010 Restricted Internal - Engineering Group 1 - Design Q1FY2010 Restricted Internal - Engineering Group 1 - Manufacturing Q1FY2010 Restricted External- Engineering Group 1 - Research Q1FY2010 Restricted External - Engineering Group 1 - Design Q1FY2010 Restricted External - Engineering Group 1 - Manufacturing Q1FY2010 Confidential Internal - Engineering Group 1 - Research Q1FY2010 Confidential Internal - Engineering Group 1 - Design Q1FY2010 Confidential Internal - Engineering Group 1 - Manufacturing Q1FY2010 Confidential External - Engineering Group 1 - Research Q1FY2010 Confidential External - Engineering Group 1 - Design Q1FY2010 Confidential External - Engineering Group 1 - Manufacturing Q1FY2010 Top Secret Internal - Engineering Group 1 - Research Q1FY2010 Top Secret Internal - Engineering Group 1 - Design Q1FY2010 Top Secret Internal - Engineering Group 1 - Manufacturing Q1FY2010 Top Secret External - Engineering Group 1 - Research Q1FY2010 Top Secret External - Engineering Group 1 - Design Q1FY2010 Top Secret External - Engineering Group 1 - Manufacturing Now multiply the above by 6 for each engineering group, 18 contexts. You are then creating/reviewing another 18 every 3 months. After a year you've got 72 contexts. What would be the advantages of such a complex classification model? You can satisfy very granular rights requirements, for example only an authorized engineering group 1 researcher can create a top secret report for access internally, and his role will be reviewed on a very frequent basis. Your business may have very complex rights requirements and mapping this directly to IRM may be an obvious exercise. The disadvantages of such a classification model are significant...Huge administrative overhead. Someone in the business must manage, review and administrate each of these contexts. If the engineering group had a single administrator, they would have 72 classifications to reside over each year. From an end users perspective life will be very confusing. Imagine if a user has rights in just 6 of these contexts. They may be able to print content from one but not another, be able to edit content in 2 contexts but not the other 4. Such confusion at the end user level causes frustration and resistance to the use of the technology. Increased synchronization complexity. Imagine a user who after 3 years in the company ends up with over 300 rights in many different contexts across the business. This would result in long synchronization times as the client software updates all your offline rights. Hard to understand who can do what with what. Imagine being the VP of engineering and as part of an internal security audit you are asked the question, "What rights to researchers have to our top secret information?". In this complex model the answer is not simple, it would depend on many roles in many contexts. Of course this example is extreme, but it highlights that trying to build many barriers in your business can result in a nightmare of administration and confusion amongst users. In the real world what we need is a balance of the two. We need to seek an optimum number of contexts. Too many contexts are unmanageable and too few contexts does not give fine enough granularity. What makes a good context? Good context design derives mainly from how well you understand your business requirements to secure access to confidential information. Some customers I have worked with can tell me exactly the documents they wish to secure and know exactly who should be opening them. However there are some customers who know only of the government regulation that requires them to control access to certain types of information, they don't actually know where the documents are, how they are created or understand exactly who should have access. Therefore you need to know how to ask the business the right questions that lead to information which help you define a context. First ask these questions about a set of documentsWhat is the topic? Who are legitimate contributors on this topic? Who are the authorized readership? If the answer to any one of these is significantly different, then it probably merits a separate context. Remember that sealed documents are inherently secure and as such they cannot leak to your competitors, therefore it is better sealed to a broad context than not sealed at all. Simplicity is key here. Always revert to the first extreme example of a single classification, then work towards essential complexity. If there is any doubt, always prefer fewer contexts. Remember, Oracle IRM allows you to change your mind later on. You can implement a design now and continue to change and refine as you learn how the technology is used. It is easy to go from a simple model to a more complex one, it is much harder to take a complex model that is already embedded in the work practice of users and try to simplify it. It is also wise to take a single use case and address this first with the business. Don't try and tackle many different problems from the outset. Do one, learn from the process, refine it and then take what you have learned into the next use case, refine and continue. Once you have a good grasp of the technology and understand how your business will use it, you can then start rolling out the technology wider across the business. Deciding on the use of roles in the context Once you have decided on that first initial use case and a context to create let's look at the details you need to decide upon. For each context, identify; Administrative rolesBusiness owner, the person who makes decisions about who may or may not see content in this context. This is often the person who wanted to use IRM and drove the business purchase. They are the usually the person with the most at risk when sensitive information is lost. Point of contact, the person who will handle requests for access to content. Sometimes the same as the business owner, sometimes a trusted secretary or administrator. Context administrator, the person who will enact the decisions of the Business Owner. Sometimes the point of contact, sometimes a trusted IT person. Document related rolesContributors, the people who create and edit documents in this context. Reviewers, the people who are involved in reviewing documents but are not trusted to secure information to this classification. This role is not always necessary. (See later discussion on Published-work and Work-in-Progress) Readers, the people who read documents from this context. Some people may have several of the roles above, which is fine. What you are trying to do is understand and define how the business interacts with your sensitive information. These roles obviously map directly to roles available in Oracle IRM. Reviewing the features and security for context roles At this point we have decided on a classification of information, understand what roles people in the business will play when administrating this classification and how they will interact with content. The final piece of the puzzle in getting the information for our first context is to look at the permissions people will have to sealed documents. First think why are you protecting the documents in the first place? It is to prevent the loss of leaking of information to the wrong people. To control the information, making sure that people only access the latest versions of documents. You are not using Oracle IRM to prevent unauthorized people from doing legitimate work. This is an important point, with IRM you can erect many barriers to prevent access to content yet too many restrictions and authorized users will often find ways to circumvent using the technology and end up distributing unprotected originals. Because IRM is a security technology, it is easy to get carried away restricting different groups. However I would highly recommend starting with a simple solution with few restrictions. Ensure that everyone who reasonably needs to read documents can do so from the outset. Remember that with Oracle IRM you can change rights to content whenever you wish and tighten security. Always return to the fact that the greatest value IRM brings is that ONLY authorized users can access secured content, remember that simple "one context for the entire business" model. At the start of the deployment you really need to aim for user acceptance and therefore a simple model is more likely to succeed. As time passes and users understand how IRM works you can start to introduce more restrictions and complexity. Another key aspect to focus on is handling exceptions. If you decide on a context model where engineering can only access engineering information, and sales can only access sales data. Act quickly when a sales manager needs legitimate access to a set of engineering documents. Having a quick and effective process for permitting other people with legitimate needs to obtain appropriate access will be rewarded with acceptance from the user community. These use cases can often be satisfied by integrating IRM with a good Identity & Access Management technology which simplifies the process of assigning users the correct business roles. The big print issue... Printing is often an issue of contention, users love to print but the business wants to ensure sensitive information remains in the controlled digital world. There are many cases of physical document loss causing a business pain, it is often overlooked that IRM can help with this issue by limiting the ability to generate physical copies of digital content. However it can be hard to maintain a balance between security and usability when it comes to printing. Consider the following points when deciding about whether to give print rights. Oracle IRM sealed documents can contain watermarks that expose information about the user, time and location of access and the classification of the document. This information would reside in the printed copy making it easier to trace who printed it. Printed documents are slower to distribute in comparison to their digital counterparts, so time sensitive information in printed format may present a lower risk. Print activity is audited, therefore you can monitor and react to users abusing print rights. Summary In summary it is important to think carefully about the way you create your context model. As you ask the business these questions you may get a variety of different requirements. There may be special projects that require a context just for sensitive information created during the lifetime of the project. There may be a department that requires all information in the group is secured and you might have a few senior executives who wish to use IRM to exchange a small number of highly sensitive documents with a very small number of people. Oracle IRM, with its very flexible context classification system, can support all of these use cases. The trick is to introducing the complexity to deliver them at the right level. In another article i'm working on I will go through some examples of how Oracle IRM might map to existing business use cases. But for now, this article covers all the important questions you need to get your IRM service deployed and successfully protecting your most sensitive information.

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