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  • ISPconfig3 + CentOS 6.2 , confused on how to move forward after initial install?

    - by Damainman
    I installed ISPCONFIG3 on centos 6.2 using the great guide on howtoforge.com. Everything is up and running and I can access ISPCONFIG via a browser. However I am not sure how to move forward with the initial setup so I can setup the very first account and get my website live. Details: Only have 1 server, the centos+ispconfig is running on a virtual machine of XEN XCP. I setup the server name to be server1.mydomain.com. I only have 2 usable ips. I plan to use them as follows: xx.xx.xx.01 : For my website and the websites of all accounts I add. xx.xx.xx.02 : For ns1.mydomain.com and ns2.mydomain.com (Yea I know they should be different ips at different locations, but this is what I have to work with at the moment.... ) I registered the nameservers at my registrar with the .02 ip. I want to use bind and ISPconfig to run the DNS on my server itself and not via my registrar. Right now if I go to the .01 IP it shows the centos+apache successful install page. So to break it down basically I am not sure where to start when it comes to: (What to consider and what to do to setup the first domain on the server) Telling bind to use the name server domains with .02. Setting up my First website(which will be my main website) in ISPconfig so mydomain.com resolves properly to my server. Make it so when you go to the .01 IP, it either redirects or shows the contents of my main website. (If this can't be done, then any advice is appreciated) Making sure that when I add a new domain, it automatically puts in the proper information for the domain so it points to the right mail, database, dns, entry. If I overlooked a tutorial then please feel free to let me know, and any advice would be greatly appreciated. Some of the tutorials I found were not specific to doing everything on only one server with Centos+Apache+Bind. Right now all I did was install centos and install ISPconfig3. Trying to move forward correctly so I don't mess up everything I did by not knowing what to do. Thank you in advance!!

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  • Moving from VPS to Cloud

    - by GRIGORE-TURBODISEL
    ...and I have a few questions. I'm basically working on a MySQL+PHP based webapp. Since I don't have on-demand scaling with VPS, I'm planning to move from VPS to Cloud when I hit the 1000 subscribers barrier. I'm looking at Windows Azure but I'm ok with other suggestions. So here are my questions: Will it really cost me a kidney? Every subscriber needs to download around 4-5MB of static resources each day. Bandwidth is free on the VPS but here I see costs can easily get to $800.00/mo; this makes me very insecure about the whole thing, I mean VPS is just $2,000/yr. Do I need another VM or is PHP included in the Web Sites? I have basic sysadmin skills, I think I can handle setting up a PHP install, but will I have to do this? If yes, what other service do I need to setup manually? What about Memcached, MySQL, etc? What security protections does it include? For example I have some basic protection included, like directory traversals and executable files upload; I also have CloudFlare on my other websites for DDoS protection; will I need to do the same thing here too, can it even be installed, can I edit my DNS records, etc? How are e-mails, subdomains, add-on domains, parked domains, etc. handled? I haven't seen any references to e-mail boxes. On the VPS I simply add them from cPanel ([email protected] / whatever.mysite.com / ...); do I have a similar management interface here? Do I get SSH access? Or at least FTP, remote MySQL access and maybe some incremental back-ups or something? Can I see my quotas and advanced traffic info? I must mention that I really like the idea of the whole "cloud" concept, the added reliability and everything but I really need maybe a parallel to regular hosting or something so I know what to expect.

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  • Script to check a shared Exchange calendar and then email detail

    - by SJN
    We're running Server and Exchange 2003 here. There's a shared calendar which HR keep up-to-date detailing staff who are on leave. I'm looking for a VB Script (or alternate) which will extract the "appointment" titles of each item for the current day and then email the detail to a mail group, in doing so notifying the group with regard to which staff are on leave for the day. The resulting email body should be: Staff on leave today: Mike Davis James Stead @Paul Robichaux - ADO is the way I went for this in the end, here are the key component for those interested: Dim Rs, Conn, Url, Username, Password, Recipient Set Rs = CreateObject("ADODB.Recordset") Set Conn = CreateObject("ADODB.Connection") 'Configurable variables Username = "Domain\username" ' AD domain\username Password = "password" ' AD password Url = "file://./backofficestorage/domain.com/MBX/username/Calendar" 'path to user's mailbox and folder Recipient = "[email protected]" Conn.Provider = "ExOLEDB.DataSource" Conn.Open Url, Username, Password Set Rs.ActiveConnection = Conn Rs.Source = "SELECT ""DAV:href"", " & _ " ""urn:schemas:httpmail:subject"", " & _ " ""urn:schemas:calendar:dtstart"", " & _ " ""urn:schemas:calendar:dtend"" " & _ "FROM scope('shallow traversal of """"') " Rs.Open Rs.MoveFirst strOutput = "" Do Until Rs.EOF If DateDiff("s", Rs.Fields("urn:schemas:calendar:dtstart"), date) >= 0 And DateDiff("s", Rs.Fields("urn:schemas:calendar:dtend"), date) < 0 Then strOutput = strOutput & "<p><font size='2' color='black' face='verdana'><b>" & Rs.Fields("urn:schemas:httpmail:subject") & "</b><br />" & vbCrLf strOutput = strOutput & "<b>From: </b>" & Rs.Fields("urn:schemas:calendar:dtstart") & vbCrLf strOutput = strOutput & "&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<b>To: </b>" & Rs.Fields("urn:schemas:calendar:dtend") & "<br /><br />" & vbCrLf End If Rs.MoveNext Loop Conn.Close Set Conn = Nothing Set Rec = Nothing After that, you can do what you like with srtOutput, I happened to use CDO to send an email: Set objMessage = CreateObject("CDO.Message") objMessage.Subject = "Subject" objMessage.From = "[email protected]" objMessage.To = Recipient objMessage.HTMLBody = strOutput objMessage.Send S

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  • Nagios core Event Handler not working

    - by sivashanmugam
    Nagios Event Handler is not triggering when the service is taking more time to response or down. My configuration in below nagios.cfg enable_event_handlers=1 localhost.cfg define service { use generic-service host_name Server service_description test-server servicegroups test-service check_command check-service is_volatile 0 check_period 24x7 max_check_attempts 4 normal_check_interval 2 retry_check_interval 2 contact_groups testcontacts notification_period 24x7 notification_options w,u,c,r notifications_enabled 1 event_handler_enabled 1 event_handler recheck-service } command.cfg define command{ command_name recheck-service command_line /usr/local/nagios/libexec/alert.sh $SERVICESTATE$ $SERVICESTATETYPE$ $SERVICEATTEMPT$ } alert.sh file !/bin/sh set -x case "$1" in OK) # The service just came back up, so don't do anything... ;; WARNING) # We don't really care about warning states, since the service is probably still running... ;; UNKNOWN) # We don't know what might be causing an unknown error, so don't do anything... ;; CRITICAL) Aha! The HTTP service appears to have a problem - perhaps we should restart the server... Is this a "soft" or a "hard" state? case "$2" in We're in a "soft" state, meaning that Nagios is in the middle of retrying the check before it turns into a "hard" state and contacts get notified... SOFT) # What check attempt are we on? We don't want to restart the web server on the first check, because it may just be a fluke! case "$3" in Wait until the check has been tried 3 times before restarting the web server. If the check fails on the 4th time (after we restart the web server), the state type will turn to "hard" and contacts will be notified of the problem. Hopefully this will restart the web server successfully, so the 4th check will result in a "soft" recovery. If that happens no one gets notified because we fixed the problem! 3) echo -n "Going To Ping the Virtual Machine (3rd soft critical state)..." # Call the init script to restart the HTTPD server myresult=`/usr/local/nagios/libexec/check_http xyz.com -t 100 | grep 'time'| awk '{print $10}'` echo "Your Service Is taking the following time Delay" "$myresult Seconds" |mail -s "WARNING : Service Taken More Time To Response" [email protected] ;; esac ;; # The HTTP service somehow managed to turn into a hard error without getting fixed. # It should have been restarted by the code above, but for some reason it didn't. # Let's give it one last try, shall we? # Note: Contacts have already been notified of a problem with the service at this

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  • Ubuntu getting wrong hostname from DHCP

    - by sam
    When provisioning new Ubuntu Precise (12.04) servers, the hostname they're getting seems to be generated from the DNS search path, not a reverse lookup on the hostname. Take the following configuration BIND is configured with the hostname, and reverse name Normal zone $TTL 600 $ORIGIN srv.local.net. @ IN SOA ns0.local.net. hostmaster.local.net. ( 2014082101 10800 3600 604800 600 ) @ IN NS ns0.local.net. @ IN MX 5 mail.local.net. my-new-server IN A 10.32.2.30 And reverse @ IN SOA ns0.local.net. hostmaster.local.net. ( 2014082101 10800 3600 604800 600 ) @ IN NS ns0.local.net. $ORIGIN 32.10.in-addr.arpa. 30.2 IN PTR my-new-server.srv.local.net. Then DHCPD is configured to hand out static leases based on mac addresses like so subnet 10.32.2.0 netmask 255.255.254.0 { option subnet-mask 255.255.254.0; option routers 10.32.2.1; option domain-name-servers 10.32.2.1; option domain-name "util.of1.local.net of1.local.net srv.local.net"; site-option-space "pxelinux"; option pxelinux.magic f1:00:74:7e; if exists dhcp-parameter-request-list { option dhcp-parameter-request-list = concat(option dhcp-parameter-request-list,d0,d1,d2,d3); } group { option pxelinux.configfile "pxelinux.cfg/pxeboot"; host my-new-server { fixed-address my-new-server.srv.local.net; hardware ethernet aa:aa:aa:bb:bb:bb; } } } So the hostname should be my-new-server.srv.local.net, however when building a Ubuntu 12.04 node, the hostname ends up as my-new-server.util.of1.local.net When building Lucid (10.04) hosts, the hostname will be correct, it's only on Precise/12.04 nodes we have the problem. Doing a normal and reverse lookup on the host and IP returns the correct result Sams-MacBook-Pro:~ sam$ host my-new-server my-new-server.srv.local.net has address 10.32.2.30 Sams-MacBook-Pro:~ sam$ host my-new-server.srv.local.net my-new-server.srv.local.net has address 10.32.2.30 Sams-MacBook-Pro:~ sam$ host 10.32.2.30 30.2.32.10.in-addr.arpa domain name pointer my-new-server.srv.local.net. The contents of the hosts file is incorrect too 127.0.0.1 localhost 127.0.1.1 my-new-server.util.of1.local.net of1.local.net srv.local.net my-new-server So it looks like when it creates the hosts file, it puts the entire contents of the DNS search path into the local address so the FQDN according to the server is the short hostname as defined, then the first domain in the search path. Is there a way to get around this behaviour, or fix this so it gets the hostname correctly? It's picking up the first part of the hostname, then the rest is wrong.

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  • Creating a network link between 2 very close buildings

    - by Daniel Johnson
    I have a charity who have two adjacent medium sized modern detached houses (in the UK): the buildings stand next to each other and are less than 5 metres apart. They have DSL connected to a single computer in one of the buildings. They want to add a network with wireless, and want it to work across both buildings. Being a charity they need to keep costs down. The network would be used for sharing Word documents, e-mail, browsing and skyping. My initial thoughts were to connect the buildings with fibre. So: Option 1 Use fibre between the buildings. Sufficient cable and two TP-LINK MC100CM Fast Ethernet Media Converters. Cost ~£80.00. But there is the extra cost and hassle of running the cable down and up the external walls, lifting and relaying paving, and burying underground. Never having fitted fibre I'm also a little worried about going up the wall and then bending the cable at 90 degrees to go through the wall and into the building. Option 2 Use two TP-Link TL-WA7510N High Powered Outdoor 5Ghz 15dBi Wireless antennas to connect the buildings. There is a clear line of sight at first floor level. Cost ~£100. And much easier to fit than fibre! Is using the TL-WA7510Ns overkill? Is there something more suitable? I had hoped to use some Netgear stuff, e.g. two DGN2200, one in each house and also use them to provide the wireless link between the buildings. However, in bridge mode wireless client association is not available and repeater mode with client association only supports WEP security which isn't strong enough. Is there something similar that would be up to the job? Option 3 Connect the buildings with UTP cable. My concerns here are risk of electric shock due to a difference of potential between the buildings (or are they so close this shouldn't be an issue) and protection from lightning strikes. Is fitting lighting arrestors expensive? And what can be done to ameliorate against the risk of shock? This all falls outside my area of expertise so I would really appreciate some advice.

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  • Confused with DKIM, SPF and Exim Configs

    - by 0pt1m1z3
    I've now spent 2 hours trying to figure out this issue and I am about to give up and go to bed. I've been having issues with Gmail rejecting emails from my VPS server because of false spam alerts (probably caused by lfd sending too many emails). So I changed my Exim config to send emails from a different IP (my VPS comes with 3) and that fixed the issue. I also enabled DKIM and SPF on my domains for added measure. But now, all my emails appear as ("From: Sender Name via server.domain1.com") where server.domain1.com is my VPS hostname. I previously had the same issue in Outlook and turning off "Set SMTP Sender: headers" solved that problem. But I believe adding the DKIM and SPF now makes Gmail add "via server.domain1.com" to my messages. How do I fix this? This is a typical header for a message (as it appears at gmail): Delivered-To: [email protected] Received: by 10.60.44.163 with SMTP id f3csp248622oem; Thu, 29 Mar 2012 21:23:18 -0700 (PDT) Received: by 10.50.106.200 with SMTP id gw8mr452788igb.10.1333081398523; Thu, 29 Mar 2012 21:23:18 -0700 (PDT) Return-Path: <[email protected]> Received: from domain2.com ([X.X.X.X]) by mx.google.com with ESMTPS id y1si810998igb.3.2012.03.29.21.23.18 (version=TLSv1/SSLv3 cipher=OTHER); Thu, 29 Mar 2012 21:23:18 -0700 (PDT) Received-SPF: pass (google.com: domain of [email protected] designates X.X.X.X as permitted sender) client-ip=X.X.X.X; Authentication-Results: mx.google.com; spf=pass (google.com: domain of [email protected] designates X.X.X.X as permitted sender) [email protected]; dkim=pass [email protected] DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=server.domain1.com; s=default; h=Date:Message-Id:From:Content-type:MIME-Version:Subject:To; bh=wF8bBRgh01EYg4t5DAeVPv1Ps906UVIeRnQCb/HvSYw=; b=k/Pg7lnrO+Ud/z1mOTv+O/3DiJzzQgyBhfIizIaFHM8tF/eNJt5P2k+9yQB224sxYstZIWwVRBJmiqvcM1QhARv1HWqWma0crppZ3JOn+LRHANan634OBi+58SIRA+gu; Received: (Exim 4.77) id 1SDTVE-0005HA-9Y for [email protected]; Fri, 30 Mar 2012 00:31:56 -0400 To: [email protected] Subject: Password Reset Request MIME-Version: 1.0 Content-type: text/html; charset=iso-8859-1 From: Sender Name <[email protected]> Message-Id: <[email protected]> Date: Fri, 30 Mar 2012 00:31:56 -0400 X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - server.domain1.com X-AntiAbuse: Original Domain - domain2.com X-AntiAbuse: Originator/Caller UID/GID - [507 504] / [47 12] X-AntiAbuse: Sender Address Domain - server.domain1.com

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  • One user sometimes gets an unknown certificate error opening Outlook

    - by Chris
    Let me clarify a little. This isn't an unknown certificate error it's an unknown certificate error in so much as I can't figure out where the certificate comes from. This happens on a Win 7 Enterprise machine connecting to Exchange 2010 with Outlook 2010. The error he gets is that the root is not trusted because it's a self-signed cert. Take a look at this screenshot because even if I had generated this myself I wouldn't have put "SomeOrganizationalUnit" or "SomeCity" or "SomeState", etc. (Red block covers our domain name.) I'm a little concerned this is a symptom of a security breach. Exchange 2010 has three certificates installed but none of them are this certificate. They all have different expiration dates (one is expired) and different meta-data. edit: There are two scenarios that I see the certificate warning and one of them I can reliably repeat. When the user leaves his computer on over night Outlook pops the Security Warning window. I don't know what time this happens. Using Outlook Anywhere if I connect to Exchange externally via a cellular USB modem the Security Warning window will appear every time I close and reopen Outlook. Whether I say Yes or No does not make a difference on whether or not I can connect to Exchange and send/receive email. In other words, I can always connect to Exchange. I've checked my two Exchange servers and my Cisco router for a certificate that matches this one and I can't find it. edit 2: Here is a screenshot of the Security Alert window. (I've been calling it Security Warning... My mistake.) edit 3: I stopped seeing this error several weeks ago but I can't tie it to any single event (because I just sort of realized that warning had stopped showing up) but I think I found the source of the certificate. Last week I found out that the certificate on our website DomainA.com was invalid. I knew that our web admin had installed a valid certificate so when I look into the problem I found out I was being presented with the invalid certificate that this posting is in regards to. The Exchange server's domain is mail.DomainA.com so I can only guess that Outlook was passing this invalid certificate through as it did some kind of check on DomainA.com. This issue is still a mystery because the certificate warning stopped appearing several weeks ago whereas the invalid certificate issue on the website was only fixed last week. It ended up being a problem with the website control panel. The valid certificate was installed but not being served for some reason and instead the self-signed cert was being served.

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  • Choice of an OS for a home ZFS NAS

    - by OlafM
    I am preparing a home NAS with an old Athlon 64 X2 3800+, 4 GB ECC RAM, Asus M2V MX motherboard, and a single 3 TB WDC Green (another one as mirror may be installed in the future). It's the cheapest solution I found that includes ECC memory and the higher energy consumption is offset by the lower (zero) cost of acquisition. The system will be used for: music storage and stream to other desktop computers; storage of the scanned dia slides (3-4k slides, 180 MB TIFF each one plus reduced quality JPEG version); stream of these photos to a local iPad 2 (maybe Plex App? not yet sure); (one additional) remote backup via rsync/ssh or ZFS send/receive. It will be controlled via remote ssh, maybe VNC, no monitor attached. Absolute requirement is a reliable ZFS solution, plus the ability to easily install packets/software/virtual machines and to update remotely (I will be the admin and I don't live near the NAS). I have mainly three options: NAS4free/FreeNAS OpenIndiana Solaris Express 11 (yeah yeah I know the license requirements, I will write a perl script on it to count it as development machine). Problems: NAS4free/FreeNAS (I tested only NAS4free) required embedded installation for remote upgrading, but full install for easy addition of software packets. Since I need at least AirVideo Server (linux/win) and Plex App (win/linux) to stream the photos and some videos to iPad (they both require virtualbox), but I cannot be there to install updates, NAS4free/FreeNAS are excluded. http://www.nas4free.org/general_information.html explains the issue: embedded can be remotely updated, full cannot. Solaris has also another advantage: Crashplan client supports Solaris and I'm already using it for other backups. I would like to leave the option open, even if I will be doing backups probably through zfs send/receive. NexentaStor was left out because zfs send/receive are not included in the free version. The question is now Solaris 11 Express over OpenIndiana. To ease the management, I will be using http://www.napp-it.org Which one would you suggest and why? I found lots of informations and it's difficult for me to decide. I think (from the napp-it manual) that Solaris has some additional options for SMB shares, but are they really needed at home? I think I won't even use ACLs, since normal unix-style permissions are enough. OpenIndiana has maybe more frequent updates (Solaris offers only security updates between releases), but again, do I need them? I don't think so. Moreover, this is a NAS that has to work and nothing else, I cannot risk having problems that require me to access the server. Isn't OpenIndiana a bit more... cutting edge (in the Solaris world)? I'm just asking, no need to focus on this for the answer :-) I would limit myself to these two options (SE11.1/OI) also because I will be making a NAS for me in the future (where high performances with Mac shares are also required) and Solaris has kernel support for AFP. I will use this server to gather experience as well. After this long question, thanks in advance! If you need additional info, let me know and I will update this post. UPDATES Given the first answers, I will strongly suggest the person paying the hardware to insert a second HD. Better 2x2TB than 1x3TB (3 TB is oversized anyway). I was trying to keep the initial costs down to spread them over a longer period, but better having something good from the beginning.

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  • How to format and where to put the SPF TXT record?

    - by YellowSquirrel
    EDIT I think I more or less understand the syntax and, anyway, Google is giving, in the link below, the syntax needed. My question is really where to put that stuff. Should I quote every field? The whole line? :) I've set up Google apps for my domain: I've registered the domain with Google by adding the CNAME Google asked and I've apparently succesfully setup the MX Google mail servers. So far I haven't yet a dedicated server: I'm just having a domain at a registrar. Now I want to activate SPF and I'm confused. In the following short webpage: http://www.google.com/support/a/bin/answer.py?answer=178723 it is written that I must add a TXT record containing: v=spf1 include:_spf.google.com ~all Where should I enter this? Should this go in the zone (?) file, like I did for the CNAME and the MX records? So far I have something like this: @ 10800 IN A 217.42.42.42 @ 10800 IN MX 5 ASPMX3.GOOGLEMAIL.COM. @ 10800 IN MX 5 ASPMX2.GOOGLEMAIL.COM. @ 10800 IN MX 3 ALT2.ASPMX.L.GOOGLE.COM. @ 10800 IN MX 3 ALT1.ASPMX.L.GOOGLE.COM. @ 10800 IN MX 1 ASPMX.L.GOOGLE.COM. google8a70835987f31e34 10800 IN CNAME google.com. Does adding the SPF TXT record mean I should literally have something like that: @ 10800 IN A 217.42.42.42 @ 10800 IN MX 5 ASPMX3.GOOGLEMAIL.COM. @ 10800 IN MX 5 ASPMX2.GOOGLEMAIL.COM. @ 3600 IN TXT "v=spf1 include:_spf.google.com ~all" @ 10800 IN MX 3 ALT2.ASPMX.L.GOOGLE.COM. @ 10800 IN MX 3 ALT1.ASPMX.L.GOOGLE.COM. @ 10800 IN MX 1 ASPMX.L.GOOGLE.COM. google8a70835987f31e34 10800 IN CNAME google.com. I made that one up and included right in the middle to show how confused I am. What I'd like to know is the exact syntax and where/how I should put this TXT record.

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  • Trying to get DNS services running on Windows Server 2008 R2, what am I getting wrong ?

    - by LaserBeak
    Ok, So I am basically trying to get a home server pc up that will provide Domain name services, act as Mail server and web server. I have one static IP, well it's not officially static but hasn't changed in two years so I'll call it static. I have done the following: Configured router NAT/virtual port forward UDP/TCP port 53 to the internal IP of my server 192.168.1.16, in adapter settings specified the manual settings: 192.168.1.16 IP, gateway 192.168.1.1, Subnet: 255.255.255.0 and loopback DNS: 127.0.0.1 Using my public my public IP Checked using http://www.canyouseeme.org/ that port 53 is open and is not being blocked by my ISP. It can see services on this port. Registered Domain name (mydomain.com.au) Updated whois database through the domain registrars site and registered NameServer names: ns0.mydomain.com.au and ns2.mydomain.com.au, both have been associated with my single public IP. (Waited 24 hours) Update the nameserver for mydomain.com.au: primary ns0.mydomain.com.au secondary: ns2.mydomain.com.au (waited 24+ hours) Installed Server 2008 R2, install web server role and DNS role. Webserver works when I enter my public IP into browser of any PC/mobile, get IIS7 welcome page. In DNS server: Created new forward lookup zone: ; ; Database file mydoman.com.au.dns for mydomain.com.au zone. ; Zone version: 10 ; @ IN SOA mydomain.com.au. mydomain.testdomain.com. ( 10 ; serial number 900 ; refresh 600 ; retry 86400 ; expire 3600 ) ; default TTL ; ; Zone NS records ; @ NS ns0.mydomain.com.au. @ NS ns1.mydomain.com.au. ; ; Zone records ; @ A 192.168.1.16 www A 192.168.1.16 The Domain name services will however not work, the whois database updated with ns0.mydomain.com.au etc. but when I type in my site name www.mydomain.com.au from an external machine it will not open site and I can't even ping it (Can't find host) When I check the ns0.mydomain.com.au NS record using a tool Like: http://www.squish.net/dnscheck/ I get: Security: Server ns0.mydomain.com.au (XXX.XXX.XXX.XX <- my public IP) is recursive Domain exists but there is no such record Any ideas, thanks...

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  • Apache SSL reverse proxy to a Embed Tomcat

    - by ggarcia24
    I'm trying to put in place a reverse proxy for an application that is running a tomcat embed server over SSL. The application needs to run over SSL on the port 9002 so I have no way of "disabling SSL" for this app. The current setup schema looks like this: [192.168.0.10:443 - Apache with mod_proxy] --> [192.168.0.10:9002 - Tomcat App] After googling on how to make such a setup (and testing) I came across this: https://bugs.launchpad.net/ubuntu/+source/openssl/+bug/861137 Which lead to make my current configuration (to try to emulate the --secure-protocol=sslv3 option of wget) /etc/apache2/sites/enabled/default-ssl: <VirtualHost _default_:443> SSLEngine On SSLCertificateFile /etc/ssl/certs/ssl-cert-snakeoil.pem SSLCertificateKeyFile /etc/ssl/private/ssl-cert-snakeoil.key SSLProxyEngine On SSLProxyProtocol SSLv3 SSLProxyCipherSuite SSLv3 ProxyPass /test/ https://192.168.0.10:9002/ ProxyPassReverse /test/ https://192.168.0.10:9002/ LogLevel debug ErrorLog /var/log/apache2/error-ssl.log CustomLog /var/log/apache2/access-ssl.log combined </VirtualHost> The thing is that the error log is showing error:14077102:SSL routines:SSL23_GET_SERVER_HELLO:unsupported protocol Complete request log: [Wed Mar 13 20:05:57 2013] [debug] mod_proxy.c(1020): Running scheme https handler (attempt 0) [Wed Mar 13 20:05:57 2013] [debug] mod_proxy_http.c(1973): proxy: HTTP: serving URL https://192.168.0.10:9002/ [Wed Mar 13 20:05:57 2013] [debug] proxy_util.c(2011): proxy: HTTPS: has acquired connection for (192.168.0.10) [Wed Mar 13 20:05:57 2013] [debug] proxy_util.c(2067): proxy: connecting https://192.168.0.10:9002/ to 192.168.0.10:9002 [Wed Mar 13 20:05:57 2013] [debug] proxy_util.c(2193): proxy: connected / to 192.168.0.10:9002 [Wed Mar 13 20:05:57 2013] [debug] proxy_util.c(2444): proxy: HTTPS: fam 2 socket created to connect to 192.168.0.10 [Wed Mar 13 20:05:57 2013] [debug] proxy_util.c(2576): proxy: HTTPS: connection complete to 192.168.0.10:9002 (192.168.0.10) [Wed Mar 13 20:05:57 2013] [info] [client 192.168.0.10] Connection to child 0 established (server demo1agrubu01.demo.lab:443) [Wed Mar 13 20:05:57 2013] [info] Seeding PRNG with 656 bytes of entropy [Wed Mar 13 20:05:57 2013] [debug] ssl_engine_kernel.c(1866): OpenSSL: Handshake: start [Wed Mar 13 20:05:57 2013] [debug] ssl_engine_kernel.c(1874): OpenSSL: Loop: before/connect initialization [Wed Mar 13 20:05:57 2013] [debug] ssl_engine_kernel.c(1874): OpenSSL: Loop: unknown state [Wed Mar 13 20:05:57 2013] [debug] ssl_engine_io.c(1897): OpenSSL: read 7/7 bytes from BIO#7f122800a100 [mem: 7f1230018f60] (BIO dump follows) [Wed Mar 13 20:05:57 2013] [debug] ssl_engine_io.c(1830): +-------------------------------------------------------------------------+ [Wed Mar 13 20:05:57 2013] [debug] ssl_engine_io.c(1869): | 0000: 15 03 01 00 02 02 50 ......P | [Wed Mar 13 20:05:57 2013] [debug] ssl_engine_io.c(1875): +-------------------------------------------------------------------------+ [Wed Mar 13 20:05:57 2013] [debug] ssl_engine_kernel.c(1903): OpenSSL: Exit: error in unknown state [Wed Mar 13 20:05:57 2013] [info] [client 192.168.0.10] SSL Proxy connect failed [Wed Mar 13 20:05:57 2013] [info] SSL Library Error: 336032002 error:14077102:SSL routines:SSL23_GET_SERVER_HELLO:unsupported protocol [Wed Mar 13 20:05:57 2013] [info] [client 192.168.0.10] Connection closed to child 0 with abortive shutdown (server example1.domain.tld:443) [Wed Mar 13 20:05:57 2013] [error] (502)Unknown error 502: proxy: pass request body failed to 172.31.4.13:9002 (192.168.0.10) [Wed Mar 13 20:05:57 2013] [error] [client 192.168.0.10] proxy: Error during SSL Handshake with remote server returned by /dsfe/ [Wed Mar 13 20:05:57 2013] [error] proxy: pass request body failed to 192.168.0.10:9002 (172.31.4.13) from 172.31.4.13 () [Wed Mar 13 20:05:57 2013] [debug] proxy_util.c(2029): proxy: HTTPS: has released connection for (172.31.4.13) [Wed Mar 13 20:05:57 2013] [debug] ssl_engine_kernel.c(1884): OpenSSL: Write: SSL negotiation finished successfully [Wed Mar 13 20:05:57 2013] [info] [client 192.168.0.10] Connection closed to child 6 with standard shutdown (server example1.domain.tld:443) If I do a wget --secure-protocol=sslv3 --no-check-certificate https://192.168.0.10:9002/ it works perfectly, but from apache is not working. I'm on an Ubuntu Server with the latest updates running apache2 with mod_proxy and mod_ssl enabled: ~$ cat /etc/lsb-release DISTRIB_ID=Ubuntu DISTRIB_RELEASE=12.04 DISTRIB_CODENAME=precise DISTRIB_DESCRIPTION="Ubuntu 12.04.2 LTS" ~# dpkg -s apache2 ... Version: 2.2.22-1ubuntu1.2 ... ~# dpkg -s openssl ... Version: 1.0.1-4ubuntu5.7 ... Hope that anyone may help

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  • In Linux, what's the best way to delegate administration responsibilities, like for Apache, a database, or some other application?

    - by Andrew Banks
    In Linux, what's the best way to delegate administration responsibilities for Apache and other "applications"? File permissions? Sudo? A mix of both? Something else? At work we have two tiers of "administrators" Operating system administrators. These are your run-of-the-mill "server administrators." They are responsible for just the operating system. Application administrators. The people who build the web site. This includes not only writing the SQL, PHP, and HTML, but also setting up and running Apache and PostgreSQL or MySQL. The aforementioned OS admins will install this stuff, but it's mainly up to the app admins to edit all the config files, start and stop processes when needed, and so on. I am one of the app admins. This is different than what I am used to. I used to just write code. The sysadmin took care not only of the OS but also installing, setting up, and keeping up the server software. But he left. Now I'm in charge of setting up Apache and the database. The new sysadmins say they just handle the operating system. It's no problem. I welcome learning new stuff. But there is a learning curve, even for the OS admins. Apache, by default, seems to be set up for administration by root directly. All the config files and scripts are 644 and owned by root:root. I'm not given the root password, naturally, so the OS admins must somehow give my ordinary OS user account all the rights necessary to edit Apache's config files, start and stop it, read its log files, and so on. Right now they're using a mix of: (1) giving me certain sudo rights, (2) adding me to certain groups, and (3) changing the file permissions of various directories, to make them writable by one of the groups I'm in. This never goes smoothly. There's always a back-and-forth between me and the sysadmins. They say it's ready. Then I try certain things, and half of them I still can't do. So they make some more changes. Then finally I seem to be independent and can administer Apache and the database without pestering them anymore. It's the sheer complication and amount of changes that make me uncomfortable. Even though it finally works, more or less, it seems hackneyed. I feel like we're doing it wrong. It seems like the makers of the software would have anticipated this scenario (someone other than root administering it) and have a clean two- or three-step program to delegate responsibility to me. But it feels like we are really chewing up the filesystem and making it far and away from the default set-up. Any suggestions? Are we doing it the recommended way? P.S. For PostgreSQL it seems a little better. Its files are owned by a system user named postgres. So giving me the right to run sudo su - postgres gives me just about everything. I'm just now getting into MySQL, but it seems to be set up similarly. But it seems a little weird doing all my work as another user.

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  • IT merger - self-sufficient site with domain controller VS thin clients outpost with access to termi

    - by imagodei
    SITUATION: A larger company acquires a smaller one. IT infrastructure has to be merged. There are no immediate plans to change the current size or role of the smaller company - the offices and production remain. It has a Win 2003 SBS domain server, Win 2000 file server, linux server for SVN and internal Wikipedia, 2 or 3 production machines, LTO backup solution. The servers are approx. 5 years old. Cisco network equippment (switches, wireless, ASA). Mail solution is a hosted Exchange. There are approx. 35 desktops and laptops in the company. IT infrastructure unification: There are 2 IT merging proposals. 1.) Replacing old servers, installing Win Server 2008 domain controller, and setting up either subdomain or domain trust to a larger company. File server and other servers remain local and synchronization should be set up to a centralized location in larger company. Similary with the backup - it remains local and if needed it should be replicated to a centralized location. Licensing is managed by smaller company. 2.) All servers are moved to a centralized location in larger company. As many desktop machines as possible are replaced by thin clients. The actual machines are virtualized and hosted by Terminal server at the same central location. Citrix solutions will be used. Only router and site-2-site VPN connection remain at the smaller company. Backup internet line to insure near 100% availability is needed. Licensing is mainly managed by larger company. Only specialized software for PCs that will not be virtualized is managed by smaller company. I'd like to ask you to discuss both solutions a bit. In your opinion, which is better from the operational point of view? Which is more reliable, cheaper in the long run? Easier to manage from the system administrator's point of view? Easier on the budget and easier to maintain from IT department's point of view? Does anybody have any experience with the second option and how does it perform in production environment? Pros and cons of both? Your input will be of great significance to me. Thank you very much!

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  • PHP, Apache and curl: Differences between Windows and Linux?

    - by beginner_
    I'm trying to run my php App on Ubuntu Server 11.10. This App works fine under Apache + PHP in windows. I have other applications that I can simply copy&paste between the 2 OS and they work on both. (These don't use cURL). However this one uses the php library tonic (RESTful webservices) and makes us of php cURL module. The issue is I'm not getting an error message which makes it impossible to find the issue. I (must) use NTLM authentication and this is done with AuthenNTLM Apache Module: Order allow,deny Allow from all PerlAuthenHandler Apache2::AuthenNTLM AuthType ntlm AuthName "Protected Access" require valid-user PerlAddVar ntdomain "domainName server" PerlSetVar defaultdomain domainName PerlSetVar ntlmsemtimeout 2 PerlSetVar ntlmdebug 1 PerlSetVar splitdomainprefix 0 All files that cURL needs to fetch override AuthenNTLM authentication: order deny,allow deny from all allow from 127.0.0.1 Satisfy any Since these files are only fectehd by cURL from same server, access can be limited to localhost. Possible issues are: NTLM auth isn't overridden for files requested through cURL (even though AllowOverride All is set) curl works differently on linux $ch = curl_init(); curl_setopt($ch, CURLOPT_COOKIE, $strCookie); curl_setopt($ch, CURLOPT_URL, $baseUrl . $queryString); curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1); $html = curl_exec($ch); curl_close($ch); other? Apache log says: [error] Bad/Missing NTLM/Basic Authorization Header for /myApp/webservice/local/viewList.php But this directory should override NTLM authentication using curl command line from windows to access same resource i get: <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN"> <html> <head> <title>406 Not Acceptable</title> </head> <body> <h1>Not Acceptable</h1> <p>An appropriate representation of the requested resource /myApp/webservice/myResource could not be found on this server.</p> Available variants: <ul> <li><a href="myResource.php">myResource.php</a> , type application/x-httpd-php</li> </ul> <hr> <address>Apache/2.2.20 (Ubuntu) Server at localhost Port 80</address> </body> </html> Note: This is duplicate from http://stackoverflow.com/questions/9821979/php-curl-on-linux-what-is-the-difference-to-curl-on-windows Is it was suggested I post it here. EDIT: Please see Ubuntu Server: Apache2 seems to attach .php to URI as I discovered why it does not work but need help so the issue does not occur anymore. ANSWER: The issue is the default Apache configuration on Ubuntu: Options Indexes FollowSymLinks MultiViews MultiViews is changing request_uri from myResource to myResource.php. Solutions: disable MultiViews in .htaccess: Options -MultiViews remove MultiViews from default config rename the file as example to myResourceClass I chose last option because that should work regardless of configuration and I only have 3 such files so the change took about 30 secs...

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  • Sharing files between multiple sites using only desktop software

    - by perlyking
    Our organisation has three sites; a head office, where the master copies of company files are stored, plus two branch offices using only workstations and a NAS or two. Currently we're talking about <10GB. At the main office, we have no admin access to the file server, as this is entirely controlled by the larger institution where we are located. For the same reason, we have no VPN remote access to this network. Instead, we simply have access to a network share using over a Novell LAN. Question: how can we share files between offices in way that minimises latency, i.e. that gives us a mirror of the main network share at each site? (There is little likelihood of concurrent editing, and we can live with the odd file conflict now and again). Up to now branch office staff have had to use GotoMyPC-type solutions to remotely access files held at the main office. Or email. I was hoping to use Google Drive on a dedicated workstation at each office to sync the contents of the network share (head office) or NAS (branch offices) via the cloud, but at my last attempt (29 Jun '12), the Google Drive installer would not allow me to designate the remote network share as the "target" folder. (I chose Google Drive over Drobbox et al. as we already use GMail for corporate mail) The next idea was to use a designated workstation at head office to mirror the network share to a local drive, then use Google Drive to push that to the cloud. This seems a step too far. Nor do I have any good ideas about how to achieve this network/local mirroring, as we can't, for example, install the rsync daemon on the server. I do not want to use Google Drive locally on each workstation as this will inconvenience users, and more importantly, move files off the backed-up, well-maintained (UPS, RAID etc) network share at head office. Our budget is only in the £100's. Should we perhaps just ditch the head office server and use something like JungleDisk? At least this presents the user with what appears to be a mapped drive.

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  • Apache's htcacheclean doesn't scale: How to tame a huge Apache disk_cache?

    - by flight
    We have an Apache setup with a huge disk_cache (500.000 entries, 50 GB disk space used). The cache grows by 16 GB every day. My problem is that the cache seems to be growing nearly as fast as it's possible to remove files and directories from the cache filesystem! The cache partition is an ext3 filesystem (100GB, "-t news") on an iSCSI storage. The Apache server (which acts as a caching proxy) is a VM. The disk_cache is configured with CacheDirLevels=2 and CacheDirLength=1, and includes variants. A typical file path is "/htcache/B/x/i_iGfmmHhxJRheg8NHcQ.header.vary/A/W/oGX3MAV3q0bWl30YmA_A.header". When I try to call htcacheclean to tame the cache (non-daemon mode, "htcacheclean-t -p/htcache -l15G"), IOwait is going through the roof for several hours. Without any visible action. Only after hours, htcacheclean starts to delete files from the cache partition, which takes a couple more hours. (A similar problem was brought up in the Apache mailing list in 2009, without a solution: http://www.mail-archive.com/[email protected]/msg42683.html) The high IOwait leads to problems with the stability of the web server (the bridge to the Tomcat backend server sometimes stalls). I came up with my own prune script, which removes files and directories from random subdirectories of the cache. Only to find that the deletion rate of the script is just slightly higher than the cache growth rate. The script takes ~10 seconds to read the a subdirectory (e.g. /htcache/B/x) and frees some 5 MB of disk space. In this 10 seconds, the cache has grown by another 2 MB. As with htcacheclean, IOwait goes up to 25% when running the prune script continuously. Any idea? Is this a problem specific to the (rather slow) iSCSI storage? Should I choose a different file system for a huge disk_cache? ext2? ext4? Are there any kernel parameter optimizations for this kind of scenario? (I already tried the deadline scheduler and a smaller read_ahead_kb, without effect).

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  • OEM sound card with no drivers or support

    - by randy
    I thought my sound card was going out so I bought a sound card online. Everything seemed to work ok, I do have sound. But after a few months, I noticed the extra software that downloaded with the sound card drivers didn't work. I ended up contacting creative and after a month of e-mail support, they asked for the serial number and/or model number. Their reply back was I had purchased an OEM sound card and they could not provide support for that, and informed me that that is why their drivers and software didn't work. They informed me that I had to contact the company that distributed the sound card and install their software. Is there anything I can do to find out who distributed this sound card, or is there anything I can do to get other features to work? I have 4 speakers and a sub but only 2 speakers produce sound. The only control I have is the volume. Creative's driver update program will find my sound card, download updates and even added software, but if I try to click on a downloaded program like Creative's Toolbox or Media Center, I get an error that it cannot find the devise. That is why I contacted creative in the first place. EDIT Thanks for the responses everyone. Here's an update. I thought I'd go thru my old computer stuff for my classes at school. I have a lot of old stuff saved, boxes and cables and stuff. I found the box the sound card came in. It looks like a box you'd buy at the store, like Best Buy or CompUSA. I worked with creative for such a long time, it went past the point of being able to return it to the junk online store this shipped from. The box did have an install CD, so I thought I'd start over to reinstall the drivers and software that shipped with the card. I noticed that the install would uninstall a program, then reinstall it. so I thought things were working out. But no good. Everything still works but the programs were still bad. I'd get an error trying to load them - not found. I'll look on the card the next time I get a chance and see if I can spot any kind of name on it.

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  • Why can't we reach some (but not all) external web service via VPN connection?

    - by Paul Haldane
    At work (UK university) we use a set of Windows servers running WS2008R2 and RRAS which offer VPN service to students in our accommodation. We do this to associate the network connections with individuals. Before they've connected to the VPN all they can talk to is the stuff thats needed to setup the VPN and a local web site with documentation on how to connect. Medium term we'll probably replace this but it's what we're using at the moment. VPN on the 2008 servers allocates client a private (10.x) address. Access to external sites is through NAT on the campus routers (same as any other directly connected client on a private address). Non-VPN connections aren't seeing this problem. Older servers run WS 2003 and ISA2004. That setup works but has become unreliable under load. Big difference there was that we were allocating non-RFC1918 addresses to the clients (so no NAT required). Behaviour we're seeing is that once connected to the VPN, clients can reach local web sites (that is sites on the campus network) but only some external sites. It seems (but this may be chance) that the sites we can reach are Google ones (including YouTube). We certainly have trouble reaching Microsoft's Office 365 service (which is a pain because that's where mail for most of our students is). One odd bit of behaviour is that clients can fetch (using wget on a Windows 7 client) http://www.oracle.com/ (which gets a 301 redirect) but hangs when asked to fetch http://www.oracle.com/index.html (which is what the first URL redirects to). Access works reliably if we configure clients to use our local web proxies (Squid). My gut tells me that this is likely to be something in the chain dropping replies either based on HTTP inspection or the IP address in the reply. However I'm puzzled about why we're seeing this with the VPN clients. Plan for tomorrow (when I'm back in the office) is to setup a web server on external connection so that we can monitor behaviour at both ends of the conversation (hoping that the problem manifests itself with our test server). Any suggestions for things we should be looking at?

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  • SQL SERVER – Retrieve and Explore Database Backup without Restoring Database – Idera virtual databas

    - by pinaldave
    I recently downloaded Idera’s SQL virtual database, and tested it. There are a few things about this tool which caught my attention. My Scenario It is quite common in real life that sometimes observing or retrieving older data is necessary; however, it had changed as time passed by. The full database backup was 40 GB in size, and, to restore it on our production server, it usually takes around 16 to 22 minutes, depending on the load server that is usually present. This range in time varies from one server to another as per the configuration of the computer. Some other issues we used to have are the following: When we try to restore a large 40-GB database, we needed at least that much space on our production server. Once in a while, we even had to make changes in the restored database, and use the said changed and restored database for our purpose, making it more time-consuming. My Solution I have heard a lot about the Idera’s SQL virtual database tool.. Well, right after we started to test this tool, we found out that it really delivers what it promises. Using this software was very easy and we were able to restore our database from backup in less than 2 minutes, sparing us from the usual longer time of 16–22 minutes. The needful was finished in a total of 10 minutes. Another interesting observation is that there is no need to have an additional space for restoring the database. For complete database restoration, the single additional MB on the drive is not required anymore. We can use the database in the same way as our regular database, and there is no need for any additional configuration and setup. Let us look at the most relevant points of this product based on my initial experience: Quick restoration of the database backup No additional space required for database restoration virtual database has no physical .MDF or .LDF The database which is restored is, in fact, the backup file converted in the virtual database. DDL and DML queries can be executed against this virtually restored database. Regular backup operation can be implemented against virtual database, creating a physical .bak file that can be used for future use. There was no observed degradation in performance on the original database as well the restored virtual database. Additional T-SQL queries can be let off on the virtual database. Well, this summarizes my quick review. And, as I was saying, I am very impressed with the product and I plan to explore it more. There are many features that I have noticed in this tool, which I think can be very useful if properly understood. I had taken a few screenshots using my demo database afterwards. Let us see what other things this tool can do besides the mentioned activities. I am surprised with its performance so I want to know how exactly this feature works, specifically in the matter of why it does not create any additional files and yet, it still allows update on the virtually restored database. I guess I will have to send an e-mail to the developers of Idera and try to figure this out from them. I think this tool is very useful, and it delivers a high level of performance way more than what I expected. Soon, I will write a review for additional uses of SQL virtual database.. If you are using SQL virtual database in your production environment, I am eager to learn more about it and your experience while using it. The ‘Virtual’ Part of virtual database When I set out to test this software, I thought virtual database had something to do with Hyper-V or visualization. In fact, the virtual database is a kind of database which shows up in your SQL Server Management Studio without actually restoring or even creating it. This tool creates a database in SSMS from the backup of the same database. The backup, however, works virtually the same way as original database. Potential Usage of virtual database: As soon as I described this tool to my teammate, I think his very first reaction was, “hey, if we have this then there is no need for log shipping.” I find his comment very interesting as log shipping is something where logs are moved to another server. In fact, there are no updates on the database from log; I would rather compare it with Snapshot Replication. In fact, whatever we use, snapshot replicated database can be similarly used and configured with virtual database. I totally believe that we can use it for reporting purpose. In fact, after this database was configured, I think the uses of this tool are unlimited. I will have to spend some more time studying it and will get back to you. Click on images to see larger images. virtual database Console Harddrive Space before virtual database Setup Attach Full Backup Screen Backup on Harddrive Attach Full Backup Screen with Settings virtual database Setup – less than 60 sec virtual database Setup – Online Harddrive Space after virtual database Setup Point in Time Recovery Option – Timeline View virtual database Summary No Performance Difference between Regular DB vs Virtual DB Please note that all SQL Server MVP gets free license of this software. Reference: Pinal Dave (http://blog.SQLAuthority.com), Idera (virtual database) Filed under: Database, Pinal Dave, SQL, SQL Add-On, SQL Authority, SQL Backup and Restore, SQL Data Storage, SQL Query, SQL Server, SQL Tips and Tricks, SQL Utility, SQLAuthority News, T SQL, Technology Tagged: Idera

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  • Consume WCF Service InProcess using Agatha and WCF

    - by REA_ANDREW
    I have been looking into this lately for a specific reason.  Some integration tests I want to write I want to control the types of instances which are used inside the service layer but I want that control from the test class instance.  One of the problems with just referencing the service is that a lot of the time this will by default be done inside a different process.  I am using StructureMap as my DI of choice and one of the tools which I am using inline with RhinoMocks is StructureMap.AutoMocking.  With StructureMap the main entry point is the ObjectFactory.  This will be process specific so if I decide that the I want a certain instance of a type to be used inside the ServiceLayer I cannot configure the ObjectFactory from my test class as that will only apply to the process which it belongs to. This is were I started thinking about two things: Running a WCF in process Being able to share mocked instances across processes A colleague in work pointed me to a project which is for the latter but I thought that it would be a better solution if I could run the WCF Service in process.  One of the projects which I use when I think about WCF Services is AGATHA, and the one which I have to used to try and get my head around doing this. Another asset I have is a book called Programming WCF Services by Juval Lowy and if you have not heard of it or read it I would definately recommend it.  One of the many topics that is inside this book is the type of configuration you need to communicate with a service in the same process, and it turns out to be quite simple from a config point of view. <system.serviceModel> <services> <service name="Agatha.ServiceLayer.WCF.WcfRequestProcessor"> <endpoint address ="net.pipe://localhost/MyPipe" binding="netNamedPipeBinding" contract="Agatha.Common.WCF.IWcfRequestProcessor"/> </service> </services> <client> <endpoint name="MyEndpoint" address="net.pipe://localhost/MyPipe" binding="netNamedPipeBinding" contract="Agatha.Common.WCF.IWcfRequestProcessor"/> </client> </system.serviceModel>   You can see here that I am referencing the Agatha object and contract here, but also that my binding and the address is something called Named Pipes.  THis is sort of the “Magic” which makes it happen in the same process. Next I need to open the service prior to calling the methods on a proxy which I also need.  My initial attempt at the proxy did not use any Agatha specific coding and one of the pains I found was that you obviously need to give your proxy the known types which the serializer can be aware of.  So we need to add to the known types of the proxy programmatically.  I came across the following blog post which showed me how easy it was http://bloggingabout.net/blogs/vagif/archive/2009/05/18/how-to-programmatically-define-known-types-in-wcf.aspx. First Pass So with this in mind, and inside a console app this was my first pass at consuming a service in process.  First here is the proxy which I made making use of the Agatha IWcfRequestProcessor contract. public class InProcProxy : ClientBase<Agatha.Common.WCF.IWcfRequestProcessor>, Agatha.Common.WCF.IWcfRequestProcessor { public InProcProxy() { } public InProcProxy(string configurationName) : base(configurationName) { } public Agatha.Common.Response[] Process(params Agatha.Common.Request[] requests) { return Channel.Process(requests); } public void ProcessOneWayRequests(params Agatha.Common.OneWayRequest[] requests) { Channel.ProcessOneWayRequests(requests); } } So with the proxy in place I could then use this after opening the service so here is the code which I use inside the console app make the request. static void Main(string[] args) { ComponentRegistration.Register(); ServiceHost serviceHost = new ServiceHost(typeof(Agatha.ServiceLayer.WCF.WcfRequestProcessor)); serviceHost.Open(); Console.WriteLine("Service is running...."); using (var proxy = new InProcProxy()) { foreach (var operation in proxy.Endpoint.Contract.Operations) { foreach (var t in KnownTypeProvider.GetKnownTypes(null)) { operation.KnownTypes.Add(t); } } var request = new GetProductsRequest(); var responses = proxy.Process(new[] { request }); var response = (GetProductsResponse)responses[0]; Console.WriteLine("{0} Products have been retrieved", response.Products.Count); } serviceHost.Close(); Console.WriteLine("Finished"); Console.ReadLine(); } So what I used here is the KnownTypeProvider of Agatha to easily get all the types I need for the service/proxy and add them to the proxy.  My Request handler for this was just a test one which always returned 2 products. public class GetProductsHandler : RequestHandler<GetProductsRequest,GetProductsResponse> { public override Agatha.Common.Response Handle(GetProductsRequest request) { return new GetProductsResponse { Products = new List<ProductDto> { new ProductDto{}, new ProductDto{} } }; } } Second Pass Now after I did this I started reading up some more on some resources including more by Davy Brion and others on Agatha.  Now it turns out that the work I did above to create a derived class of the ClientBase implementing Agatha.Common.WCF.IWcfRequestProcessor was not necessary due to a nice class which is present inside the Agatha code base, RequestProcessorProxy which takes care of this for you! :-) So disregarding that class I made for the proxy and changing my code to use it I am now left with the following: static void Main(string[] args) { ComponentRegistration.Register(); ServiceHost serviceHost = new ServiceHost(typeof(Agatha.ServiceLayer.WCF.WcfRequestProcessor)); serviceHost.Open(); Console.WriteLine("Service is running...."); using (var proxy = new RequestProcessorProxy()) { var request = new GetProductsRequest(); var responses = proxy.Process(new[] { request }); var response = (GetProductsResponse)responses[0]; Console.WriteLine("{0} Products have been retrieved", response.Products.Count); } serviceHost.Close(); Console.WriteLine("Finished"); Console.ReadLine(); }   Cheers for now, Andy References Agatha WCF InProcess Without WCF StructureMap.AutoMocking Cross Process Mocking Agatha Programming WCF Services by Juval Lowy

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  • Agile Development

    - by James Oloo Onyango
    Alot of literature has and is being written about agile developement and its surrounding philosophies. In my quest to find the best way to express the importance of agile methodologies, i have found Robert C. Martin's "A Satire Of Two Companies" to be both the most concise and thorough! Enjoy the read! Rufus Inc Project Kick Off Your name is Bob. The date is January 3, 2001, and your head still aches from the recent millennial revelry. You are sitting in a conference room with several managers and a group of your peers. You are a project team leader. Your boss is there, and he has brought along all of his team leaders. His boss called the meeting. "We have a new project to develop," says your boss's boss. Call him BB. The points in his hair are so long that they scrape the ceiling. Your boss's points are just starting to grow, but he eagerly awaits the day when he can leave Brylcream stains on the acoustic tiles. BB describes the essence of the new market they have identified and the product they want to develop to exploit this market. "We must have this new project up and working by fourth quarter October 1," BB demands. "Nothing is of higher priority, so we are cancelling your current project." The reaction in the room is stunned silence. Months of work are simply going to be thrown away. Slowly, a murmur of objection begins to circulate around the conference table.   His points give off an evil green glow as BB meets the eyes of everyone in the room. One by one, that insidious stare reduces each attendee to quivering lumps of protoplasm. It is clear that he will brook no discussion on this matter. Once silence has been restored, BB says, "We need to begin immediately. How long will it take you to do the analysis?" You raise your hand. Your boss tries to stop you, but his spitwad misses you and you are unaware of his efforts.   "Sir, we can't tell you how long the analysis will take until we have some requirements." "The requirements document won't be ready for 3 or 4 weeks," BB says, his points vibrating with frustration. "So, pretend that you have the requirements in front of you now. How long will you require for analysis?" No one breathes. Everyone looks around to see whether anyone has some idea. "If analysis goes beyond April 1, we have a problem. Can you finish the analysis by then?" Your boss visibly gathers his courage: "We'll find a way, sir!" His points grow 3 mm, and your headache increases by two Tylenol. "Good." BB smiles. "Now, how long will it take to do the design?" "Sir," you say. Your boss visibly pales. He is clearly worried that his 3 mms are at risk. "Without an analysis, it will not be possible to tell you how long design will take." BB's expression shifts beyond austere.   "PRETEND you have the analysis already!" he says, while fixing you with his vacant, beady little eyes. "How long will it take you to do the design?" Two Tylenol are not going to cut it. Your boss, in a desperate attempt to save his new growth, babbles: "Well, sir, with only six months left to complete the project, design had better take no longer than 3 months."   "I'm glad you agree, Smithers!" BB says, beaming. Your boss relaxes. He knows his points are secure. After a while, he starts lightly humming the Brylcream jingle. BB continues, "So, analysis will be complete by April 1, design will be complete by July 1, and that gives you 3 months to implement the project. This meeting is an example of how well our new consensus and empowerment policies are working. Now, get out there and start working. I'll expect to see TQM plans and QIT assignments on my desk by next week. Oh, and don't forget that your crossfunctional team meetings and reports will be needed for next month's quality audit." "Forget the Tylenol," you think to yourself as you return to your cubicle. "I need bourbon."   Visibly excited, your boss comes over to you and says, "Gosh, what a great meeting. I think we're really going to do some world shaking with this project." You nod in agreement, too disgusted to do anything else. "Oh," your boss continues, "I almost forgot." He hands you a 30-page document. "Remember that the SEI is coming to do an evaluation next week. This is the evaluation guide. You need to read through it, memorize it, and then shred it. It tells you how to answer any questions that the SEI auditors ask you. It also tells you what parts of the building you are allowed to take them to and what parts to avoid. We are determined to be a CMM level 3 organization by June!"   You and your peers start working on the analysis of the new project. This is difficult because you have no requirements. But from the 10-minute introduction given by BB on that fateful morning, you have some idea of what the product is supposed to do.   Corporate process demands that you begin by creating a use case document. You and your team begin enumerating use cases and drawing oval and stick diagrams. Philosophical debates break out among the team members. There is disagreement as to whether certain use cases should be connected with <<extends>> or <<includes>> relationships. Competing models are created, but nobody knows how to evaluate them. The debate continues, effectively paralyzing progress.   After a week, somebody finds the iceberg.com Web site, which recommends disposing entirely of <<extends>> and <<includes>> and replacing them with <<precedes>> and <<uses>>. The documents on this Web site, authored by Don Sengroiux, describes a method known as stalwart-analysis, which claims to be a step-by-step method for translating use cases into design diagrams. More competing use case models are created using this new scheme, but again, people can't agree on how to evaluate them. The thrashing continues. More and more, the use case meetings are driven by emotion rather than by reason. If it weren't for the fact that you don't have requirements, you'd be pretty upset by the lack of progress you are making. The requirements document arrives on February 15. And then again on February 20, 25, and every week thereafter. Each new version contradicts the previous one. Clearly, the marketing folks who are writing the requirements, empowered though they might be, are not finding consensus.   At the same time, several new competing use case templates have been proposed by the various team members. Each template presents its own particularly creative way of delaying progress. The debates rage on. On March 1, Prudence Putrigence, the process proctor, succeeds in integrating all the competing use case forms and templates into a single, all-encompassing form. Just the blank form is 15 pages long. She has managed to include every field that appeared on all the competing templates. She also presents a 159- page document describing how to fill out the use case form. All current use cases must be rewritten according to the new standard.   You marvel to yourself that it now requires 15 pages of fill-in-the-blank and essay questions to answer the question: What should the system do when the user presses Return? The corporate process (authored by L. E. Ott, famed author of "Holistic Analysis: A Progressive Dialectic for Software Engineers") insists that you discover all primary use cases, 87 percent of all secondary use cases, and 36.274 percent of all tertiary use cases before you can complete analysis and enter the design phase. You have no idea what a tertiary use case is. So in an attempt to meet this requirement, you try to get your use case document reviewed by the marketing department, which you hope will know what a tertiary use case is.   Unfortunately, the marketing folks are too busy with sales support to talk to you. Indeed, since the project started, you have not been able to get a single meeting with marketing, which has provided a never-ending stream of changing and contradictory requirements documents.   While one team has been spinning endlessly on the use case document, another team has been working out the domain model. Endless variations of UML documents are pouring out of this team. Every week, the model is reworked.   The team members can't decide whether to use <<interfaces>> or <<types>> in the model. A huge disagreement has been raging on the proper syntax and application of OCL. Others on the team just got back from a 5-day class on catabolism, and have been producing incredibly detailed and arcane diagrams that nobody else can fathom.   On March 27, with one week to go before analysis is to be complete, you have produced a sea of documents and diagrams but are no closer to a cogent analysis of the problem than you were on January 3. **** And then, a miracle happens.   **** On Saturday, April 1, you check your e-mail from home. You see a memo from your boss to BB. It states unequivocally that you are done with the analysis! You phone your boss and complain. "How could you have told BB that we were done with the analysis?" "Have you looked at a calendar lately?" he responds. "It's April 1!" The irony of that date does not escape you. "But we have so much more to think about. So much more to analyze! We haven't even decided whether to use <<extends>> or <<precedes>>!" "Where is your evidence that you are not done?" inquires your boss, impatiently. "Whaaa . . . ." But he cuts you off. "Analysis can go on forever; it has to be stopped at some point. And since this is the date it was scheduled to stop, it has been stopped. Now, on Monday, I want you to gather up all existing analysis materials and put them into a public folder. Release that folder to Prudence so that she can log it in the CM system by Monday afternoon. Then get busy and start designing."   As you hang up the phone, you begin to consider the benefits of keeping a bottle of bourbon in your bottom desk drawer. They threw a party to celebrate the on-time completion of the analysis phase. BB gave a colon-stirring speech on empowerment. And your boss, another 3 mm taller, congratulated his team on the incredible show of unity and teamwork. Finally, the CIO takes the stage to tell everyone that the SEI audit went very well and to thank everyone for studying and shredding the evaluation guides that were passed out. Level 3 now seems assured and will be awarded by June. (Scuttlebutt has it that managers at the level of BB and above are to receive significant bonuses once the SEI awards level 3.)   As the weeks flow by, you and your team work on the design of the system. Of course, you find that the analysis that the design is supposedly based on is flawedno, useless; no, worse than useless. But when you tell your boss that you need to go back and work some more on the analysis to shore up its weaker sections, he simply states, "The analysis phase is over. The only allowable activity is design. Now get back to it."   So, you and your team hack the design as best you can, unsure of whether the requirements have been properly analyzed. Of course, it really doesn't matter much, since the requirements document is still thrashing with weekly revisions, and the marketing department still refuses to meet with you.     The design is a nightmare. Your boss recently misread a book named The Finish Line in which the author, Mark DeThomaso, blithely suggested that design documents should be taken down to code-level detail. "If we are going to be working at that level of detail," you ask, "why don't we simply write the code instead?" "Because then you wouldn't be designing, of course. And the only allowable activity in the design phase is design!" "Besides," he continues, "we have just purchased a companywide license for Dandelion! This tool enables 'Round the Horn Engineering!' You are to transfer all design diagrams into this tool. It will automatically generate our code for us! It will also keep the design diagrams in sync with the code!" Your boss hands you a brightly colored shrinkwrapped box containing the Dandelion distribution. You accept it numbly and shuffle off to your cubicle. Twelve hours, eight crashes, one disk reformatting, and eight shots of 151 later, you finally have the tool installed on your server. You consider the week your team will lose while attending Dandelion training. Then you smile and think, "Any week I'm not here is a good week." Design diagram after design diagram is created by your team. Dandelion makes it very difficult to draw these diagrams. There are dozens and dozens of deeply nested dialog boxes with funny text fields and check boxes that must all be filled in correctly. And then there's the problem of moving classes between packages. At first, these diagram are driven from the use cases. But the requirements are changing so often that the use cases rapidly become meaningless. Debates rage about whether VISITOR or DECORATOR design patterns should be used. One developer refuses to use VISITOR in any form, claiming that it's not a properly object-oriented construct. Someone refuses to use multiple inheritance, since it is the spawn of the devil. Review meetings rapidly degenerate into debates about the meaning of object orientation, the definition of analysis versus design, or when to use aggregation versus association. Midway through the design cycle, the marketing folks announce that they have rethought the focus of the system. Their new requirements document is completely restructured. They have eliminated several major feature areas and replaced them with feature areas that they anticipate customer surveys will show to be more appropriate. You tell your boss that these changes mean that you need to reanalyze and redesign much of the system. But he says, "The analysis phase is system. But he says, "The analysis phase is over. The only allowable activity is design. Now get back to it."   You suggest that it might be better to create a simple prototype to show to the marketing folks and even some potential customers. But your boss says, "The analysis phase is over. The only allowable activity is design. Now get back to it." Hack, hack, hack, hack. You try to create some kind of a design document that might reflect the new requirements documents. However, the revolution of the requirements has not caused them to stop thrashing. Indeed, if anything, the wild oscillations of the requirements document have only increased in frequency and amplitude.   You slog your way through them.   On June 15, the Dandelion database gets corrupted. Apparently, the corruption has been progressive. Small errors in the DB accumulated over the months into bigger and bigger errors. Eventually, the CASE tool just stopped working. Of course, the slowly encroaching corruption is present on all the backups. Calls to the Dandelion technical support line go unanswered for several days. Finally, you receive a brief e-mail from Dandelion, informing you that this is a known problem and that the solution is to purchase the new version, which they promise will be ready some time next quarter, and then reenter all the diagrams by hand.   ****   Then, on July 1 another miracle happens! You are done with the design!   Rather than go to your boss and complain, you stock your middle desk drawer with some vodka.   **** They threw a party to celebrate the on-time completion of the design phase and their graduation to CMM level 3. This time, you find BB's speech so stirring that you have to use the restroom before it begins. New banners and plaques are all over your workplace. They show pictures of eagles and mountain climbers, and they talk about teamwork and empowerment. They read better after a few scotches. That reminds you that you need to clear out your file cabinet to make room for the brandy. You and your team begin to code. But you rapidly discover that the design is lacking in some significant areas. Actually, it's lacking any significance at all. You convene a design session in one of the conference rooms to try to work through some of the nastier problems. But your boss catches you at it and disbands the meeting, saying, "The design phase is over. The only allowable activity is coding. Now get back to it."   ****   The code generated by Dandelion is really hideous. It turns out that you and your team were using association and aggregation the wrong way, after all. All the generated code has to be edited to correct these flaws. Editing this code is extremely difficult because it has been instrumented with ugly comment blocks that have special syntax that Dandelion needs in order to keep the diagrams in sync with the code. If you accidentally alter one of these comments, the diagrams will be regenerated incorrectly. It turns out that "Round the Horn Engineering" requires an awful lot of effort. The more you try to keep the code compatible with Dandelion, the more errors Dandelion generates. In the end, you give up and decide to keep the diagrams up to date manually. A second later, you decide that there's no point in keeping the diagrams up to date at all. Besides, who has time?   Your boss hires a consultant to build tools to count the number of lines of code that are being produced. He puts a big thermometer graph on the wall with the number 1,000,000 on the top. Every day, he extends the red line to show how many lines have been added. Three days after the thermometer appears on the wall, your boss stops you in the hall. "That graph isn't growing quickly enough. We need to have a million lines done by October 1." "We aren't even sh-sh-sure that the proshect will require a m-million linezh," you blather. "We have to have a million lines done by October 1," your boss reiterates. His points have grown again, and the Grecian formula he uses on them creates an aura of authority and competence. "Are you sure your comment blocks are big enough?" Then, in a flash of managerial insight, he says, "I have it! I want you to institute a new policy among the engineers. No line of code is to be longer than 20 characters. Any such line must be split into two or more preferably more. All existing code needs to be reworked to this standard. That'll get our line count up!"   You decide not to tell him that this will require two unscheduled work months. You decide not to tell him anything at all. You decide that intravenous injections of pure ethanol are the only solution. You make the appropriate arrangements. Hack, hack, hack, and hack. You and your team madly code away. By August 1, your boss, frowning at the thermometer on the wall, institutes a mandatory 50-hour workweek.   Hack, hack, hack, and hack. By September 1st, the thermometer is at 1.2 million lines and your boss asks you to write a report describing why you exceeded the coding budget by 20 percent. He institutes mandatory Saturdays and demands that the project be brought back down to a million lines. You start a campaign of remerging lines. Hack, hack, hack, and hack. Tempers are flaring; people are quitting; QA is raining trouble reports down on you. Customers are demanding installation and user manuals; salespeople are demanding advance demonstrations for special customers; the requirements document is still thrashing, the marketing folks are complaining that the product isn't anything like they specified, and the liquor store won't accept your credit card anymore. Something has to give.    On September 15, BB calls a meeting. As he enters the room, his points are emitting clouds of steam. When he speaks, the bass overtones of his carefully manicured voice cause the pit of your stomach to roll over. "The QA manager has told me that this project has less than 50 percent of the required features implemented. He has also informed me that the system crashes all the time, yields wrong results, and is hideously slow. He has also complained that he cannot keep up with the continuous train of daily releases, each more buggy than the last!" He stops for a few seconds, visibly trying to compose himself. "The QA manager estimates that, at this rate of development, we won't be able to ship the product until December!" Actually, you think it's more like March, but you don't say anything. "December!" BB roars with such derision that people duck their heads as though he were pointing an assault rifle at them. "December is absolutely out of the question. Team leaders, I want new estimates on my desk in the morning. I am hereby mandating 65-hour work weeks until this project is complete. And it better be complete by November 1."   As he leaves the conference room, he is heard to mutter: "Empowermentbah!" * * * Your boss is bald; his points are mounted on BB's wall. The fluorescent lights reflecting off his pate momentarily dazzle you. "Do you have anything to drink?" he asks. Having just finished your last bottle of Boone's Farm, you pull a bottle of Thunderbird from your bookshelf and pour it into his coffee mug. "What's it going to take to get this project done? " he asks. "We need to freeze the requirements, analyze them, design them, and then implement them," you say callously. "By November 1?" your boss exclaims incredulously. "No way! Just get back to coding the damned thing." He storms out, scratching his vacant head.   A few days later, you find that your boss has been transferred to the corporate research division. Turnover has skyrocketed. Customers, informed at the last minute that their orders cannot be fulfilled on time, have begun to cancel their orders. Marketing is re-evaluating whether this product aligns with the overall goals of the company. Memos fly, heads roll, policies change, and things are, overall, pretty grim. Finally, by March, after far too many sixty-five hour weeks, a very shaky version of the software is ready. In the field, bug-discovery rates are high, and the technical support staff are at their wits' end, trying to cope with the complaints and demands of the irate customers. Nobody is happy.   In April, BB decides to buy his way out of the problem by licensing a product produced by Rupert Industries and redistributing it. The customers are mollified, the marketing folks are smug, and you are laid off.     Rupert Industries: Project Alpha   Your name is Robert. The date is January 3, 2001. The quiet hours spent with your family this holiday have left you refreshed and ready for work. You are sitting in a conference room with your team of professionals. The manager of the division called the meeting. "We have some ideas for a new project," says the division manager. Call him Russ. He is a high-strung British chap with more energy than a fusion reactor. He is ambitious and driven but understands the value of a team. Russ describes the essence of the new market opportunity the company has identified and introduces you to Jane, the marketing manager, who is responsible for defining the products that will address it. Addressing you, Jane says, "We'd like to start defining our first product offering as soon as possible. When can you and your team meet with me?" You reply, "We'll be done with the current iteration of our project this Friday. We can spare a few hours for you between now and then. After that, we'll take a few people from the team and dedicate them to you. We'll begin hiring their replacements and the new people for your team immediately." "Great," says Russ, "but I want you to understand that it is critical that we have something to exhibit at the trade show coming up this July. If we can't be there with something significant, we'll lose the opportunity."   "I understand," you reply. "I don't yet know what it is that you have in mind, but I'm sure we can have something by July. I just can't tell you what that something will be right now. In any case, you and Jane are going to have complete control over what we developers do, so you can rest assured that by July, you'll have the most important things that can be accomplished in that time ready to exhibit."   Russ nods in satisfaction. He knows how this works. Your team has always kept him advised and allowed him to steer their development. He has the utmost confidence that your team will work on the most important things first and will produce a high-quality product.   * * *   "So, Robert," says Jane at their first meeting, "How does your team feel about being split up?" "We'll miss working with each other," you answer, "but some of us were getting pretty tired of that last project and are looking forward to a change. So, what are you people cooking up?" Jane beams. "You know how much trouble our customers currently have . . ." And she spends a half hour or so describing the problem and possible solution. "OK, wait a second" you respond. "I need to be clear about this." And so you and Jane talk about how this system might work. Some of her ideas aren't fully formed. You suggest possible solutions. She likes some of them. You continue discussing.   During the discussion, as each new topic is addressed, Jane writes user story cards. Each card represents something that the new system has to do. The cards accumulate on the table and are spread out in front of you. Both you and Jane point at them, pick them up, and make notes on them as you discuss the stories. The cards are powerful mnemonic devices that you can use to represent complex ideas that are barely formed.   At the end of the meeting, you say, "OK, I've got a general idea of what you want. I'm going to talk to the team about it. I imagine they'll want to run some experiments with various database structures and presentation formats. Next time we meet, it'll be as a group, and we'll start identifying the most important features of the system."   A week later, your nascent team meets with Jane. They spread the existing user story cards out on the table and begin to get into some of the details of the system. The meeting is very dynamic. Jane presents the stories in the order of their importance. There is much discussion about each one. The developers are concerned about keeping the stories small enough to estimate and test. So they continually ask Jane to split one story into several smaller stories. Jane is concerned that each story have a clear business value and priority, so as she splits them, she makes sure that this stays true.   The stories accumulate on the table. Jane writes them, but the developers make notes on them as needed. Nobody tries to capture everything that is said; the cards are not meant to capture everything but are simply reminders of the conversation.   As the developers become more comfortable with the stories, they begin writing estimates on them. These estimates are crude and budgetary, but they give Jane an idea of what the story will cost.   At the end of the meeting, it is clear that many more stories could be discussed. It is also clear that the most important stories have been addressed and that they represent several months worth of work. Jane closes the meeting by taking the cards with her and promising to have a proposal for the first release in the morning.   * * *   The next morning, you reconvene the meeting. Jane chooses five cards and places them on the table. "According to your estimates, these cards represent about one perfect team-week's worth of work. The last iteration of the previous project managed to get one perfect team-week done in 3 real weeks. If we can get these five stories done in 3 weeks, we'll be able to demonstrate them to Russ. That will make him feel very comfortable about our progress." Jane is pushing it. The sheepish look on her face lets you know that she knows it too. You reply, "Jane, this is a new team, working on a new project. It's a bit presumptuous to expect that our velocity will be the same as the previous team's. However, I met with the team yesterday afternoon, and we all agreed that our initial velocity should, in fact, be set to one perfectweek for every 3 real-weeks. So you've lucked out on this one." "Just remember," you continue, "that the story estimates and the story velocity are very tentative at this point. We'll learn more when we plan the iteration and even more when we implement it."   Jane looks over her glasses at you as if to say "Who's the boss around here, anyway?" and then smiles and says, "Yeah, don't worry. I know the drill by now."Jane then puts 15 more cards on the table. She says, "If we can get all these cards done by the end of March, we can turn the system over to our beta test customers. And we'll get good feedback from them."   You reply, "OK, so we've got our first iteration defined, and we have the stories for the next three iterations after that. These four iterations will make our first release."   "So," says Jane, can you really do these five stories in the next 3 weeks?" "I don't know for sure, Jane," you reply. "Let's break them down into tasks and see what we get."   So Jane, you, and your team spend the next several hours taking each of the five stories that Jane chose for the first iteration and breaking them down into small tasks. The developers quickly realize that some of the tasks can be shared between stories and that other tasks have commonalities that can probably be taken advantage of. It is clear that potential designs are popping into the developers' heads. From time to time, they form little discussion knots and scribble UML diagrams on some cards.   Soon, the whiteboard is filled with the tasks that, once completed, will implement the five stories for this iteration. You start the sign-up process by saying, "OK, let's sign up for these tasks." "I'll take the initial database generation." Says Pete. "That's what I did on the last project, and this doesn't look very different. I estimate it at two of my perfect workdays." "OK, well, then, I'll take the login screen," says Joe. "Aw, darn," says Elaine, the junior member of the team, "I've never done a GUI, and kinda wanted to try that one."   "Ah, the impatience of youth," Joe says sagely, with a wink in your direction. "You can assist me with it, young Jedi." To Jane: "I think it'll take me about three of my perfect workdays."   One by one, the developers sign up for tasks and estimate them in terms of their own perfect workdays. Both you and Jane know that it is best to let the developers volunteer for tasks than to assign the tasks to them. You also know full well that you daren't challenge any of the developers' estimates. You know these people, and you trust them. You know that they are going to do the very best they can.   The developers know that they can't sign up for more perfect workdays than they finished in the last iteration they worked on. Once each developer has filled his or her schedule for the iteration, they stop signing up for tasks.   Eventually, all the developers have stopped signing up for tasks. But, of course, tasks are still left on the board.   "I was worried that that might happen," you say, "OK, there's only one thing to do, Jane. We've got too much to do in this iteration. What stories or tasks can we remove?" Jane sighs. She knows that this is the only option. Working overtime at the beginning of a project is insane, and projects where she's tried it have not fared well.   So Jane starts to remove the least-important functionality. "Well, we really don't need the login screen just yet. We can simply start the system in the logged-in state." "Rats!" cries Elaine. "I really wanted to do that." "Patience, grasshopper." says Joe. "Those who wait for the bees to leave the hive will not have lips too swollen to relish the honey." Elaine looks confused. Everyone looks confused. "So . . .," Jane continues, "I think we can also do away with . . ." And so, bit by bit, the list of tasks shrinks. Developers who lose a task sign up for one of the remaining ones.   The negotiation is not painless. Several times, Jane exhibits obvious frustration and impatience. Once, when tensions are especially high, Elaine volunteers, "I'll work extra hard to make up some of the missing time." You are about to correct her when, fortunately, Joe looks her in the eye and says, "When once you proceed down the dark path, forever will it dominate your destiny."   In the end, an iteration acceptable to Jane is reached. It's not what Jane wanted. Indeed, it is significantly less. But it's something the team feels that can be achieved in the next 3 weeks.   And, after all, it still addresses the most important things that Jane wanted in the iteration. "So, Jane," you say when things had quieted down a bit, "when can we expect acceptance tests from you?" Jane sighs. This is the other side of the coin. For every story the development team implements,   Jane must supply a suite of acceptance tests that prove that it works. And the team needs these long before the end of the iteration, since they will certainly point out differences in the way Jane and the developers imagine the system's behaviour.   "I'll get you some example test scripts today," Jane promises. "I'll add to them every day after that. You'll have the entire suite by the middle of the iteration."   * * *   The iteration begins on Monday morning with a flurry of Class, Responsibilities, Collaborators sessions. By midmorning, all the developers have assembled into pairs and are rapidly coding away. "And now, my young apprentice," Joe says to Elaine, "you shall learn the mysteries of test-first design!"   "Wow, that sounds pretty rad," Elaine replies. "How do you do it?" Joe beams. It's clear that he has been anticipating this moment. "OK, what does the code do right now?" "Huh?" replied Elaine, "It doesn't do anything at all; there is no code."   "So, consider our task; can you think of something the code should do?" "Sure," Elaine said with youthful assurance, "First, it should connect to the database." "And thereupon, what must needs be required to connecteth the database?" "You sure talk weird," laughed Elaine. "I think we'd have to get the database object from some registry and call the Connect() method. "Ah, astute young wizard. Thou perceives correctly that we requireth an object within which we can cacheth the database object." "Is 'cacheth' really a word?" "It is when I say it! So, what test can we write that we know the database registry should pass?" Elaine sighs. She knows she'll just have to play along. "We should be able to create a database object and pass it to the registry in a Store() method. And then we should be able to pull it out of the registry with a Get() method and make sure it's the same object." "Oh, well said, my prepubescent sprite!" "Hay!" "So, now, let's write a test function that proves your case." "But shouldn't we write the database object and registry object first?" "Ah, you've much to learn, my young impatient one. Just write the test first." "But it won't even compile!" "Are you sure? What if it did?" "Uh . . ." "Just write the test, Elaine. Trust me." And so Joe, Elaine, and all the other developers began to code their tasks, one test case at a time. The room in which they worked was abuzz with the conversations between the pairs. The murmur was punctuated by an occasional high five when a pair managed to finish a task or a difficult test case.   As development proceeded, the developers changed partners once or twice a day. Each developer got to see what all the others were doing, and so knowledge of the code spread generally throughout the team.   Whenever a pair finished something significant whether a whole task or simply an important part of a task they integrated what they had with the rest of the system. Thus, the code base grew daily, and integration difficulties were minimized.   The developers communicated with Jane on a daily basis. They'd go to her whenever they had a question about the functionality of the system or the interpretation of an acceptance test case.   Jane, good as her word, supplied the team with a steady stream of acceptance test scripts. The team read these carefully and thereby gained a much better understanding of what Jane expected the system to do. By the beginning of the second week, there was enough functionality to demonstrate to Jane. She watched eagerly as the demonstration passed test case after test case. "This is really cool," Jane said as the demonstration finally ended. "But this doesn't seem like one-third of the tasks. Is your velocity slower than anticipated?"   You grimace. You'd been waiting for a good time to mention this to Jane but now she was forcing the issue. "Yes, unfortunately, we are going more slowly than we had expected. The new application server we are using is turning out to be a pain to configure. Also, it takes forever to reboot, and we have to reboot it whenever we make even the slightest change to its configuration."   Jane eyes you with suspicion. The stress of last Monday's negotiations had still not entirely dissipated. She says, "And what does this mean to our schedule? We can't slip it again, we just can't. Russ will have a fit! He'll haul us all into the woodshed and ream us some new ones."   You look Jane right in the eyes. There's no pleasant way to give someone news like this. So you just blurt out, "Look, if things keep going like they're going, we're not going to be done with everything by next Friday. Now it's possible that we'll figure out a way to go faster. But, frankly, I wouldn't depend on that. You should start thinking about one or two tasks that could be removed from the iteration without ruining the demonstration for Russ. Come hell or high water, we are going to give that demonstration on Friday, and I don't think you want us to choose which tasks to omit."   "Aw forchrisakes!" Jane barely manages to stifle yelling that last word as she stalks away, shaking her head. Not for the first time, you say to yourself, "Nobody ever promised me project management would be easy." You are pretty sure it won't be the last time, either.   Actually, things went a bit better than you had hoped. The team did, in fact, have to drop one task from the iteration, but Jane had chosen wisely, and the demonstration for Russ went without a hitch. Russ was not impressed with the progress, but neither was he dismayed. He simply said, "This is pretty good. But remember, we have to be able to demonstrate this system at the trade show in July, and at this rate, it doesn't look like you'll have all that much to show." Jane, whose attitude had improved dramatically with the completion of the iteration, responded to Russ by saying, "Russ, this team is working hard, and well. When July comes around, I am confident that we'll have something significant to demonstrate. It won't be everything, and some of it may be smoke and mirrors, but we'll have something."   Painful though the last iteration was, it had calibrated your velocity numbers. The next iteration went much better. Not because your team got more done than in the last iteration but simply because the team didn't have to remove any tasks or stories in the middle of the iteration.   By the start of the fourth iteration, a natural rhythm has been established. Jane, you, and the team know exactly what to expect from one another. The team is running hard, but the pace is sustainable. You are confident that the team can keep up this pace for a year or more.   The number of surprises in the schedule diminishes to near zero; however, the number of surprises in the requirements does not. Jane and Russ frequently look over the growing system and make recommendations or changes to the existing functionality. But all parties realize that these changes take time and must be scheduled. So the changes do not cause anyone's expectations to be violated. In March, there is a major demonstration of the system to the board of directors. The system is very limited and is not yet in a form good enough to take to the trade show, but progress is steady, and the board is reasonably impressed.   The second release goes even more smoothly than the first. By now, the team has figured out a way to automate Jane's acceptance test scripts. The team has also refactored the design of the system to the point that it is really easy to add new features and change old ones. The second release was done by the end of June and was taken to the trade show. It had less in it than Jane and Russ would have liked, but it did demonstrate the most important features of the system. Although customers at the trade show noticed that certain features were missing, they were very impressed overall. You, Russ, and Jane all returned from the trade show with smiles on your faces. You all felt as though this project was a winner.   Indeed, many months later, you are contacted by Rufus Inc. That company had been working on a system like this for its internal operations. Rufus has canceled the development of that system after a death-march project and is negotiating to license your technology for its environment.   Indeed, things are looking up!

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  • Try out Windows Phone 7 on your PC today

    - by Matthew Guay
    Anticipation has been building for the new Windows Phone 7 Series ever since Microsoft unveiled it at the Mobile World Congress in February.  Now, thanks to free developer tools, you can get a first-hand experience of the basic Windows Phone 7 Series devices on your PC. Windows Phone 7 Series represents a huge change in the mobile field for Microsoft, bringing the acclaimed Zune HD UI to an innovative phone platform.  Windows Mobile has often been criticized for being behind other Smartphone platforms, but Microsoft seeks to regain the lead with this new upcoming release.  A platform must have developers behind it to be useful, so they have released a full set of free development tools so anyone can make apps for it today.  Or, if you simply want to play with Windows Phone 7, you can use the included emulator to try out the new Metro UI.  Here’s how to do this today on your Vista or 7 computer. Please note: These tools are a Customer Technology Preview release, so only install them if you’re comfortable using pre-release software. Getting Started First, download the Windows Phone Developer Tools CTP (link below), and run the installer.  This will install the Customer Technology Preview (CTP) versions of Visual Studio 2010 Express for Windows Phone, Windows Phone Emulator, Silverlight for Windows Phone, and XNA 4.0 Game Studio on your computer, all of which are required and cannot be installed individually. Accept the license agreement when prompted. Click “Install Now” to install the tools you need.  The only setup customization option is where to save the files, so choose Customize if you need to do so. Setup will now automatically download and install the components you need, and will additionally download either 32 or 64 bit programs depending on your operating system. About halfway thorough the installation, you’ll be prompted to reboot your system.  Once your computer is rebooted, setup will automatically resume without further input.   When setup is finished, click “Run the Product Now” to get started. Running Windows Phone 7 on your PC Now that you’ve got the Windows Phone Developer tools installed, it’s time to get the Windows Phone emulator running.  If you clicked “Run the Product Now” when the setup finished, Visual Studio 2010 Express for Windows Phone should have already started.   If not, simply enter “visual studio” in your start menu search and select “Microsoft Visual Studio 2010 Express for Windows Phone”. Now, to run the Windows Phone 7 emulator, we have to test an application.  So, even if you don’t know how to program, we can open a phone application template, and then test it to run the emulator.  First, click New Project on the left hand side of the front page. Any of the application templates would work for this, but here let’s select “Windows Phone Application”, and then click Ok. Here’s your new application template, which already contains the basic phone application framework.  This is where you’d start if you want to develop a Windows Phone app, but for now we just want to see Windows Phone 7 in action. So, to run the emulator, click Debug in the menu and then select Start Debugging. Your new application will launch inside the Windows Phone 7 Series emulator.  The default template doesn’t give us much, but it does show an example application running in Windows Phone 7.   Exploring Windows Phone 7 Click the Windows button on the emulator to go to the home screen.  Notice the Zune HD-like transition animation.  The emulator only includes Internet Explorer, your test application, and a few settings. Click the arrow on the right to see the available applications in a list. Settings lets you change the theme, regional settings, and the date and time in your emulator.  It also has an applications settings pane, but this currently isn’t populated. The Time settings shows a unique Windows Phone UI. You can return to the home screen by pressing the Windows button.  Here’s the Internet Explorer app running, with the virtual keyboard open to enter an address.  Please note that this emulator can also accept input from your keyboard, so you can enter addresses without clicking on the virtual keyboard. And here’s Google running in Internet Explorer on Windows Phone 7. Windows Phone 7 supports accelerometers, and you can simulate this in the emulator.  Click one of the rotate buttons to rotate the screen in that direction. Here’s our favorite website in Internet Explorer on Windows Phone 7 in landscape mode. All this, running right inside your Windows 7 desktop… Developer tools for Windows Phone 7 Although it may be fun to play with the Windows Phone 7 emulator, developers will be more excited to actually be able to create new and exciting apps for it.  The Windows Phone Developer Tools download includes Visual Studio Express and XNA Game Studio 4.0 which lets you create enticing games and apps for Windows Phones.  All development for Windows Phones will be in C#, Silverlight, and the XNA game framework.  Visual Studio Express for Windows Phone includes templates for these, and additionally has code samples to help you get started with development. Conclusion Many features are still not functional in this preview version, such as the search button and most of the included applications.  However, this still gives you a great way to experience firsthand the future of the Windows Phone platform.  And, for developers, this is your chance to set your mark on the Windows Phone 7 Series even before it is released to the public.  Happy playing and developing! Links Download Windows Phone Developer Tools CTP Windows Phone Developer Site Similar Articles Productive Geek Tips Keep Track of Homework Assignments with SoshikuWeekend Fun: Watch Television On Your PC With TVUPlayerEasily Manage Your Downloads with Download StatusbarCreate a Shortcut or Hotkey to Mute the System Volume in WindowsHow-To Geek on Lifehacker: How to Make Windows Vista Less Annoying TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Convert the Quick Launch Bar into a Super Application Launcher Automate Tasks in Linux with Crontab Discover New Bundled Feeds in Google Reader Play Music in Chrome by Simply Dragging a File 15 Great Illustrations by Chow Hon Lam Easily Sync Files & Folders with Friends & Family

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  • Test All Features of Windows Phone 7 On Your PC

    - by Matthew Guay
    Are you developer or just excited about the upcoming Windows Phone 7, and want to try it out now?  Thanks to free developer tools from Microsoft and a new unlocked emulator rom, you can try out most of the exciting features today from your PC. Last week we showed you how to try out Windows Phone 7 on your PC and get started developing for the upcoming new devices.  We noticed, however, that the emulator only contains Internet Explorer Mobile and some settings.  This is still interesting to play around with, but it wasn’t the full Windows Phone 7 experience. Some enterprising tweakers discovered that more applications were actually included in the emulator, but were simply hidden from users.  Developer Dan Ardelean then figured out how to re-enable these features, and released a tweaked emulator rom so everyone can try out all of the Windows Phone 7 features for themselves.  Here we’ll look at how you can run this new emulator image on your PC, and then look at some interesting features in Windows Phone 7. Editor Note: This modified emulator image is not official, and isn’t sanctioned by Microsoft. Use your own judgment when choosing to download and use the emulator. Setting Up Emulator Rom To test-drive Windows Phone 7 on your PC, you must first download and install the Windows Phone Developer Tools CTP (link below).  Follow the steps we showed you last week at: Try out Windows Phone 7 on your PC today.  Once it’s installed, go ahead and run the default emulator as we showed to make sure everything works ok. Once the Windows Phone Developer Tools are installed and running, download the new emulator rom from XDA Forums (link below).  This will be a zip file, so extract it first. Note where you save the file, as you will need the address in the next step. Now, to run our new emulator image, we need to open the emulator in command line and point to the new rom image.  To do this, browse to the correct directory, depending on whether you’re running the 32 bit or 64 bit version of Windows: 32 bit: C:\Program Files\Microsoft XDE\1.0\ 64 bit: C:\Program Files (x86)\Microsoft XDE\1.0\ Hold your Shift key down and right-click in the folder.  Choose Open Command Window here. At the command prompt, enter XDE.exe followed by the location of your new rom image.  Here, we downloaded the rom to our download folder, so at the command prompt we entered: XDE.exe C:\Users\Matthew\Downloads\WM70Full\WM70Full.bin The emulator loads … with the full Windows Phone 7 experience! To make it easier, let’s make a shortcut on our desktop to load the emulator with the new rom directly.  Right-click on your desktop (or any folder you want to create the shortcut in), select New, and then Shortcut. Now, in the box, we need to enter the path for the emulator followed by the location of our rom.  Both items must be in quotes.  So, in our test, we entered the following: 32 bit: “C:\Program Files\Microsoft XDE\1.0\” “C:\Users\Matthew\Downloads\WM70Full\WM70Full.bin” 64 bit: “C:\Program Files (x86)\Microsoft XDE\1.0\” “C:\Users\Matthew\Downloads\WM70Full\WM70Full.bin” Make sure to enter the correct location of the new emulator rom for your computer, and keep both items in separate quotes.  Click next when you’ve entered the location. Name the shortcut; we named it Windows Phone 7, but simply enter whatever you’d like.  Click Finish when you’re done. You should now have a nice Windows Phone icon and your fully functional shortcut!  Double-click it to run the Windows Phone 7 emulator as above. Features in the Unlocked Windows Phone 7 Emulator So let’s look at what you can do with this new emulator.  Almost everything you’ve seen in demos from the Mobile World Conference and Mix’10 are right here for you to play with.  Here’s the application menu, which you can access by clicking on the arrow on the top of the home screen, which shows how much stuff they’ve got in this!   And, of course, even the home screen itself shows much more activity than it did in the original emulator. Let’s check out some of these sections.  Here’s Zune running on Windows Phone 7, and the Zune Marketplace.  The animations are beautiful, so be sure to check this out yourself. The new picture hub is much nicer than any picture viewer included with Windows Mobile in the past…   Stay productive, and on schedule with the new Calendar. The XBOX hub gives us only a hint of things to come, and the links to games now are simply placeholders. Here’s a look at the Office hub.  This doesn’t show up on the homescreen right now, but you can access it in the applications menu.  Office obviously still has a lot of work left on it, but even at a glance here it looks like it includes a lot more functionality than Office Mobile in Windows Mobile 6. Here’s a look at each of the three apps: Word, Excel, and OneNote, and the formatting pallet in Office apps.   This emulator also includes a lot more settings than the default one, including settings for individual applications. You can even activate the screen lock, and try out the lift-to-peek-or-unlock feature… Finally, this version of Windows Phone 7 includes a very nice SystemInfo app with an advanced task manager.  We hope this is still available when the actual phones are released. Conclusion If you’re excited about the upcoming Windows Phone 7 series, or simply want to learn more about what’s coming, this is a great way to test it out.  With these exciting new hubs and applications, there’s something here for everyone.  Let us know what you like most about Windows Phone 7 and what your favorite app or hub is. Links Please note: These roms are not officially supported by Microsoft, and could be taken down. Download the unlocked Windows Phone 7 emulator from XDA Forums – click the link in this post to download How the unlocked emulator image was created Similar Articles Productive Geek Tips Try out Windows Phone 7 on your PC todayGet stats on your Ruby on Rails codeDisable Windows Vista’s Built-in CD/DVD Burning FeaturesWeek in Geek – The Slick Windows 7 File Copy Animation EditionGeek Fun: Virtualized Old School Windows – Windows 95 TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Get Better Windows Search With UltraSearch Scan News With NY Times Article Skimmer SpeedyFox Claims to Speed up your Firefox Beware Hover Kitties Test Drive Mobile Phones Online With TryPhone Ben & Jerry’s Free Cone Day, 3/23/10

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  • How LINQ to Object statements work

    - by rajbk
    This post goes into detail as to now LINQ statements work when querying a collection of objects. This topic assumes you have an understanding of how generics, delegates, implicitly typed variables, lambda expressions, object/collection initializers, extension methods and the yield statement work. I would also recommend you read my previous two posts: Using Delegates in C# Part 1 Using Delegates in C# Part 2 We will start by writing some methods to filter a collection of data. Assume we have an Employee class like so: 1: public class Employee { 2: public int ID { get; set;} 3: public string FirstName { get; set;} 4: public string LastName {get; set;} 5: public string Country { get; set; } 6: } and a collection of employees like so: 1: var employees = new List<Employee> { 2: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 3: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 4: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 5: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" }, 6: }; Filtering We wish to  find all employees that have an even ID. We could start off by writing a method that takes in a list of employees and returns a filtered list of employees with an even ID. 1: static List<Employee> GetEmployeesWithEvenID(List<Employee> employees) { 2: var filteredEmployees = new List<Employee>(); 3: foreach (Employee emp in employees) { 4: if (emp.ID % 2 == 0) { 5: filteredEmployees.Add(emp); 6: } 7: } 8: return filteredEmployees; 9: } The method can be rewritten to return an IEnumerable<Employee> using the yield return keyword. 1: static IEnumerable<Employee> GetEmployeesWithEvenID(IEnumerable<Employee> employees) { 2: foreach (Employee emp in employees) { 3: if (emp.ID % 2 == 0) { 4: yield return emp; 5: } 6: } 7: } We put these together in a console application. 1: using System; 2: using System.Collections.Generic; 3: //No System.Linq 4:  5: public class Program 6: { 7: [STAThread] 8: static void Main(string[] args) 9: { 10: var employees = new List<Employee> { 11: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 12: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 13: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 14: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" }, 15: }; 16: var filteredEmployees = GetEmployeesWithEvenID(employees); 17:  18: foreach (Employee emp in filteredEmployees) { 19: Console.WriteLine("ID {0} First_Name {1} Last_Name {2} Country {3}", 20: emp.ID, emp.FirstName, emp.LastName, emp.Country); 21: } 22:  23: Console.ReadLine(); 24: } 25: 26: static IEnumerable<Employee> GetEmployeesWithEvenID(IEnumerable<Employee> employees) { 27: foreach (Employee emp in employees) { 28: if (emp.ID % 2 == 0) { 29: yield return emp; 30: } 31: } 32: } 33: } 34:  35: public class Employee { 36: public int ID { get; set;} 37: public string FirstName { get; set;} 38: public string LastName {get; set;} 39: public string Country { get; set; } 40: } Output: ID 2 First_Name Jim Last_Name Ashlock Country UK ID 4 First_Name Jill Last_Name Anderson Country AUS Our filtering method is too specific. Let us change it so that it is capable of doing different types of filtering and lets give our method the name Where ;-) We will add another parameter to our Where method. This additional parameter will be a delegate with the following declaration. public delegate bool Filter(Employee emp); The idea is that the delegate parameter in our Where method will point to a method that contains the logic to do our filtering thereby freeing our Where method from any dependency. The method is shown below: 1: static IEnumerable<Employee> Where(IEnumerable<Employee> employees, Filter filter) { 2: foreach (Employee emp in employees) { 3: if (filter(emp)) { 4: yield return emp; 5: } 6: } 7: } Making the change to our app, we create a new instance of the Filter delegate on line 14 with a target set to the method EmployeeHasEvenId. Running the code will produce the same output. 1: public delegate bool Filter(Employee emp); 2:  3: public class Program 4: { 5: [STAThread] 6: static void Main(string[] args) 7: { 8: var employees = new List<Employee> { 9: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 10: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 11: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 12: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 13: }; 14: var filterDelegate = new Filter(EmployeeHasEvenId); 15: var filteredEmployees = Where(employees, filterDelegate); 16:  17: foreach (Employee emp in filteredEmployees) { 18: Console.WriteLine("ID {0} First_Name {1} Last_Name {2} Country {3}", 19: emp.ID, emp.FirstName, emp.LastName, emp.Country); 20: } 21: Console.ReadLine(); 22: } 23: 24: static bool EmployeeHasEvenId(Employee emp) { 25: return emp.ID % 2 == 0; 26: } 27: 28: static IEnumerable<Employee> Where(IEnumerable<Employee> employees, Filter filter) { 29: foreach (Employee emp in employees) { 30: if (filter(emp)) { 31: yield return emp; 32: } 33: } 34: } 35: } 36:  37: public class Employee { 38: public int ID { get; set;} 39: public string FirstName { get; set;} 40: public string LastName {get; set;} 41: public string Country { get; set; } 42: } Lets use lambda expressions to inline the contents of the EmployeeHasEvenId method in place of the method. The next code snippet shows this change (see line 15).  For brevity, the Employee class declaration has been skipped. 1: public delegate bool Filter(Employee emp); 2:  3: public class Program 4: { 5: [STAThread] 6: static void Main(string[] args) 7: { 8: var employees = new List<Employee> { 9: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 10: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 11: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 12: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 13: }; 14: var filterDelegate = new Filter(EmployeeHasEvenId); 15: var filteredEmployees = Where(employees, emp => emp.ID % 2 == 0); 16:  17: foreach (Employee emp in filteredEmployees) { 18: Console.WriteLine("ID {0} First_Name {1} Last_Name {2} Country {3}", 19: emp.ID, emp.FirstName, emp.LastName, emp.Country); 20: } 21: Console.ReadLine(); 22: } 23: 24: static bool EmployeeHasEvenId(Employee emp) { 25: return emp.ID % 2 == 0; 26: } 27: 28: static IEnumerable<Employee> Where(IEnumerable<Employee> employees, Filter filter) { 29: foreach (Employee emp in employees) { 30: if (filter(emp)) { 31: yield return emp; 32: } 33: } 34: } 35: } 36:  The output displays the same two employees.  Our Where method is too restricted since it works with a collection of Employees only. Lets change it so that it works with any IEnumerable<T>. In addition, you may recall from my previous post,  that .NET 3.5 comes with a lot of predefined delegates including public delegate TResult Func<T, TResult>(T arg); We will get rid of our Filter delegate and use the one above instead. We apply these two changes to our code. 1: public class Program 2: { 3: [STAThread] 4: static void Main(string[] args) 5: { 6: var employees = new List<Employee> { 7: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 8: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 9: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 10: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 11: }; 12:  13: var filteredEmployees = Where(employees, emp => emp.ID % 2 == 0); 14:  15: foreach (Employee emp in filteredEmployees) { 16: Console.WriteLine("ID {0} First_Name {1} Last_Name {2} Country {3}", 17: emp.ID, emp.FirstName, emp.LastName, emp.Country); 18: } 19: Console.ReadLine(); 20: } 21: 22: static IEnumerable<T> Where<T>(IEnumerable<T> source, Func<T, bool> filter) { 23: foreach (var x in source) { 24: if (filter(x)) { 25: yield return x; 26: } 27: } 28: } 29: } We have successfully implemented a way to filter any IEnumerable<T> based on a  filter criteria. Projection Now lets enumerate on the items in the IEnumerable<Employee> we got from the Where method and copy them into a new IEnumerable<EmployeeFormatted>. The EmployeeFormatted class will only have a FullName and ID property. 1: public class EmployeeFormatted { 2: public int ID { get; set; } 3: public string FullName {get; set;} 4: } We could “project” our existing IEnumerable<Employee> into a new collection of IEnumerable<EmployeeFormatted> with the help of a new method. We will call this method Select ;-) 1: static IEnumerable<EmployeeFormatted> Select(IEnumerable<Employee> employees) { 2: foreach (var emp in employees) { 3: yield return new EmployeeFormatted { 4: ID = emp.ID, 5: FullName = emp.LastName + ", " + emp.FirstName 6: }; 7: } 8: } The changes are applied to our app. 1: public class Program 2: { 3: [STAThread] 4: static void Main(string[] args) 5: { 6: var employees = new List<Employee> { 7: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 8: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 9: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 10: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 11: }; 12:  13: var filteredEmployees = Where(employees, emp => emp.ID % 2 == 0); 14: var formattedEmployees = Select(filteredEmployees); 15:  16: foreach (EmployeeFormatted emp in formattedEmployees) { 17: Console.WriteLine("ID {0} Full_Name {1}", 18: emp.ID, emp.FullName); 19: } 20: Console.ReadLine(); 21: } 22:  23: static IEnumerable<T> Where<T>(IEnumerable<T> source, Func<T, bool> filter) { 24: foreach (var x in source) { 25: if (filter(x)) { 26: yield return x; 27: } 28: } 29: } 30: 31: static IEnumerable<EmployeeFormatted> Select(IEnumerable<Employee> employees) { 32: foreach (var emp in employees) { 33: yield return new EmployeeFormatted { 34: ID = emp.ID, 35: FullName = emp.LastName + ", " + emp.FirstName 36: }; 37: } 38: } 39: } 40:  41: public class Employee { 42: public int ID { get; set;} 43: public string FirstName { get; set;} 44: public string LastName {get; set;} 45: public string Country { get; set; } 46: } 47:  48: public class EmployeeFormatted { 49: public int ID { get; set; } 50: public string FullName {get; set;} 51: } Output: ID 2 Full_Name Ashlock, Jim ID 4 Full_Name Anderson, Jill We have successfully selected employees who have an even ID and then shaped our data with the help of the Select method so that the final result is an IEnumerable<EmployeeFormatted>.  Lets make our Select method more generic so that the user is given the freedom to shape what the output would look like. We can do this, like before, with lambda expressions. Our Select method is changed to accept a delegate as shown below. TSource will be the type of data that comes in and TResult will be the type the user chooses (shape of data) as returned from the selector delegate. 1:  2: static IEnumerable<TResult> Select<TSource, TResult>(IEnumerable<TSource> source, Func<TSource, TResult> selector) { 3: foreach (var x in source) { 4: yield return selector(x); 5: } 6: } We see the new changes to our app. On line 15, we use lambda expression to specify the shape of the data. In this case the shape will be of type EmployeeFormatted. 1:  2: public class Program 3: { 4: [STAThread] 5: static void Main(string[] args) 6: { 7: var employees = new List<Employee> { 8: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 9: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 10: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 11: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 12: }; 13:  14: var filteredEmployees = Where(employees, emp => emp.ID % 2 == 0); 15: var formattedEmployees = Select(filteredEmployees, (emp) => 16: new EmployeeFormatted { 17: ID = emp.ID, 18: FullName = emp.LastName + ", " + emp.FirstName 19: }); 20:  21: foreach (EmployeeFormatted emp in formattedEmployees) { 22: Console.WriteLine("ID {0} Full_Name {1}", 23: emp.ID, emp.FullName); 24: } 25: Console.ReadLine(); 26: } 27: 28: static IEnumerable<T> Where<T>(IEnumerable<T> source, Func<T, bool> filter) { 29: foreach (var x in source) { 30: if (filter(x)) { 31: yield return x; 32: } 33: } 34: } 35: 36: static IEnumerable<TResult> Select<TSource, TResult>(IEnumerable<TSource> source, Func<TSource, TResult> selector) { 37: foreach (var x in source) { 38: yield return selector(x); 39: } 40: } 41: } The code outputs the same result as before. On line 14 we filter our data and on line 15 we project our data. What if we wanted to be more expressive and concise? We could combine both line 14 and 15 into one line as shown below. Assuming you had to perform several operations like this on our collection, you would end up with some very unreadable code! 1: var formattedEmployees = Select(Where(employees, emp => emp.ID % 2 == 0), (emp) => 2: new EmployeeFormatted { 3: ID = emp.ID, 4: FullName = emp.LastName + ", " + emp.FirstName 5: }); A cleaner way to write this would be to give the appearance that the Select and Where methods were part of the IEnumerable<T>. This is exactly what extension methods give us. Extension methods have to be defined in a static class. Let us make the Select and Where extension methods on IEnumerable<T> 1: public static class MyExtensionMethods { 2: static IEnumerable<T> Where<T>(this IEnumerable<T> source, Func<T, bool> filter) { 3: foreach (var x in source) { 4: if (filter(x)) { 5: yield return x; 6: } 7: } 8: } 9: 10: static IEnumerable<TResult> Select<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector) { 11: foreach (var x in source) { 12: yield return selector(x); 13: } 14: } 15: } The creation of the extension method makes the syntax much cleaner as shown below. We can write as many extension methods as we want and keep on chaining them using this technique. 1: var formattedEmployees = employees 2: .Where(emp => emp.ID % 2 == 0) 3: .Select (emp => new EmployeeFormatted { ID = emp.ID, FullName = emp.LastName + ", " + emp.FirstName }); Making these changes and running our code produces the same result. 1: using System; 2: using System.Collections.Generic; 3:  4: public class Program 5: { 6: [STAThread] 7: static void Main(string[] args) 8: { 9: var employees = new List<Employee> { 10: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 11: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 12: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 13: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 14: }; 15:  16: var formattedEmployees = employees 17: .Where(emp => emp.ID % 2 == 0) 18: .Select (emp => 19: new EmployeeFormatted { 20: ID = emp.ID, 21: FullName = emp.LastName + ", " + emp.FirstName 22: } 23: ); 24:  25: foreach (EmployeeFormatted emp in formattedEmployees) { 26: Console.WriteLine("ID {0} Full_Name {1}", 27: emp.ID, emp.FullName); 28: } 29: Console.ReadLine(); 30: } 31: } 32:  33: public static class MyExtensionMethods { 34: static IEnumerable<T> Where<T>(this IEnumerable<T> source, Func<T, bool> filter) { 35: foreach (var x in source) { 36: if (filter(x)) { 37: yield return x; 38: } 39: } 40: } 41: 42: static IEnumerable<TResult> Select<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector) { 43: foreach (var x in source) { 44: yield return selector(x); 45: } 46: } 47: } 48:  49: public class Employee { 50: public int ID { get; set;} 51: public string FirstName { get; set;} 52: public string LastName {get; set;} 53: public string Country { get; set; } 54: } 55:  56: public class EmployeeFormatted { 57: public int ID { get; set; } 58: public string FullName {get; set;} 59: } Let’s change our code to return a collection of anonymous types and get rid of the EmployeeFormatted type. We see that the code produces the same output. 1: using System; 2: using System.Collections.Generic; 3:  4: public class Program 5: { 6: [STAThread] 7: static void Main(string[] args) 8: { 9: var employees = new List<Employee> { 10: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 11: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 12: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 13: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 14: }; 15:  16: var formattedEmployees = employees 17: .Where(emp => emp.ID % 2 == 0) 18: .Select (emp => 19: new { 20: ID = emp.ID, 21: FullName = emp.LastName + ", " + emp.FirstName 22: } 23: ); 24:  25: foreach (var emp in formattedEmployees) { 26: Console.WriteLine("ID {0} Full_Name {1}", 27: emp.ID, emp.FullName); 28: } 29: Console.ReadLine(); 30: } 31: } 32:  33: public static class MyExtensionMethods { 34: public static IEnumerable<T> Where<T>(this IEnumerable<T> source, Func<T, bool> filter) { 35: foreach (var x in source) { 36: if (filter(x)) { 37: yield return x; 38: } 39: } 40: } 41: 42: public static IEnumerable<TResult> Select<TSource, TResult>(this IEnumerable<TSource> source, Func<TSource, TResult> selector) { 43: foreach (var x in source) { 44: yield return selector(x); 45: } 46: } 47: } 48:  49: public class Employee { 50: public int ID { get; set;} 51: public string FirstName { get; set;} 52: public string LastName {get; set;} 53: public string Country { get; set; } 54: } To be more expressive, C# allows us to write our extension method calls as a query expression. Line 16 can be rewritten a query expression like so: 1: var formattedEmployees = from emp in employees 2: where emp.ID % 2 == 0 3: select new { 4: ID = emp.ID, 5: FullName = emp.LastName + ", " + emp.FirstName 6: }; When the compiler encounters an expression like the above, it simply rewrites it as calls to our extension methods.  So far we have been using our extension methods. The System.Linq namespace contains several extension methods for objects that implement the IEnumerable<T>. You can see a listing of these methods in the Enumerable class in the System.Linq namespace. Let’s get rid of our extension methods (which I purposefully wrote to be of the same signature as the ones in the Enumerable class) and use the ones provided in the Enumerable class. Our final code is shown below: 1: using System; 2: using System.Collections.Generic; 3: using System.Linq; //Added 4:  5: public class Program 6: { 7: [STAThread] 8: static void Main(string[] args) 9: { 10: var employees = new List<Employee> { 11: new Employee { ID = 1, FirstName = "John", LastName = "Wright", Country = "USA" }, 12: new Employee { ID = 2, FirstName = "Jim", LastName = "Ashlock", Country = "UK" }, 13: new Employee { ID = 3, FirstName = "Jane", LastName = "Jackson", Country = "CHE" }, 14: new Employee { ID = 4, FirstName = "Jill", LastName = "Anderson", Country = "AUS" } 15: }; 16:  17: var formattedEmployees = from emp in employees 18: where emp.ID % 2 == 0 19: select new { 20: ID = emp.ID, 21: FullName = emp.LastName + ", " + emp.FirstName 22: }; 23:  24: foreach (var emp in formattedEmployees) { 25: Console.WriteLine("ID {0} Full_Name {1}", 26: emp.ID, emp.FullName); 27: } 28: Console.ReadLine(); 29: } 30: } 31:  32: public class Employee { 33: public int ID { get; set;} 34: public string FirstName { get; set;} 35: public string LastName {get; set;} 36: public string Country { get; set; } 37: } 38:  39: public class EmployeeFormatted { 40: public int ID { get; set; } 41: public string FullName {get; set;} 42: } This post has shown you a basic overview of LINQ to Objects work by showning you how an expression is converted to a sequence of calls to extension methods when working directly with objects. It gets more interesting when working with LINQ to SQL where an expression tree is constructed – an in memory data representation of the expression. The C# compiler compiles these expressions into code that builds an expression tree at runtime. The provider can then traverse the expression tree and generate the appropriate SQL query. You can read more about expression trees in this MSDN article.

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