Search Results

Search found 44902 results on 1797 pages for 'call naive true'.

Page 504/1797 | < Previous Page | 500 501 502 503 504 505 506 507 508 509 510 511  | Next Page >

• Network traffic is not being forwarded from a VM to the network using a bridged interface with Xen + libvirt

  - by foob

  I'm having trouble getting network access from a VM that I'm running using Xen and libvirt. I've been trying different things and reading similar posts online for a couple of days but I'm really stuck at this point. If anybody could offer some insight it would be much appreciated. I have a VM that I'm running on a host with a bridge set up as br0 and an interface eth0 on a 192.168.60.0/24 subnet. The networking portion of the libvirt configuration xml is: <interface type='bridge'> <mac address='ff:a0:d1:e5:07:de'/> <source bridge='br0'/> <script path='/etc/xen/scripts/vif-bridge'/> <model type='virtio' /> </interface> When I start the VM a vif6.0 interface is created on the host and the ifconfig output is: br0 Link encap:Ethernet HWaddr 00:A0:D1:C3:07:DE inet addr:192.168.60.33 Bcast:192.168.60.255 Mask:255.255.255.0 inet6 addr: fe80::2a0:d1ff:fee5:7de/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:13 errors:0 dropped:0 overruns:0 frame:0 TX packets:40 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:3570 (3.4 KiB) TX bytes:3508 (3.4 KiB) eth0 Link encap:Ethernet HWaddr 00:A0:D1:C3:07:DE inet6 addr: fe80::2a0:d1ff:fee5:7de/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:6 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 b) TX bytes:492 (492.0 b) Interrupt:19 Memory:fe8f0000-fe900000 vif6.0 Link encap:Ethernet HWaddr FE:FF:FF:FF:FF:FF inet6 addr: fe80::fcff:ffff:feff:ffff/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:80 errors:0 dropped:0 overruns:0 frame:0 TX packets:6 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:500 RX bytes:6660 (6.5 KiB) TX bytes:468 (468.0 b) virbr0 Link encap:Ethernet HWaddr 00:00:00:00:00:00 inet addr:192.168.122.1 Bcast:192.168.122.255 Mask:255.255.255.0 UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:0 (0.0 b) TX bytes:0 (0.0 b) The 'brctl show' output seems to show the bridge being configured correctly: br0 8000.00a0d1e507de no eth0 vif6.0 The ifcfg-eth0 contents in the VM are: DEVICE=eth0 BOOTPROTO=static HWADDR=FF:A0:D1:E5:07:DE IPADDR=192.168.60.133 NETMASK=255.255.255.0 ONBOOT=yes and the output of ifconfig in the VM look like what I would expect: eth0 Link encap:Ethernet HWaddr FF:A0:D1:E5:07:DE inet addr:192.168.60.133 Bcast:192.168.60.255 Mask:255.255.255.0 inet6 addr: fe80::fda0:d1ff:fee5:7de/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:6 errors:0 dropped:0 overruns:0 frame:0 TX packets:80 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:468 (468.0 b) TX bytes:7780 (7.5 KiB) but when I try to ssh or ping another computer I get 'no route to host.' Using tcpdump on the host system I tried to see if I could narrow down where the problem is: # tcpdump -vv -i vif6.0 tcpdump: WARNING: vif6.0: no IPv4 address assigned tcpdump: listening on vif6.0, link-type EN10MB (Ethernet), capture size 96 bytes 14:49:40.833997 arp who-has 192.168.60.35 tell 192.168.60.133 14:49:41.833314 arp who-has 192.168.60.35 tell 192.168.60.133 14:49:42.833309 arp who-has 192.168.60.35 tell 192.168.60.133 So the VM is sending out out an arp who-has packet when I try to ssh to 192.168.60.35. I think that this means the setup within the VM is ok and that this is an issue on the host system. If I run tcpdump with the interface of br0 then I don't see these arp packets. My thought here is that the packets are being blocked before going on to the bridge somehow. I tried adding an iptables rule to resolve this: -A FORWARD -m physdev --physdev-is-bridged -j ACCEPT but it didn't work. I also tried the following: /sbin/sysctl -w net.bridge.bridge-nf-call-ip6tables=0 /sbin/sysctl -w net.bridge.bridge-nf-call-iptables=0 /sbin/sysctl -w net.bridge.bridge-nf-call-arptables=0 /sbin/sysctl -w net.ipv4.ip_forward=1 which had no impact. Is it obvious to somebody who has more experience than me what I'm missing here? Should vif6.0 have the same MAC address is eth0 in the vm? Do I need more rules in my iptables? Thanks for any help!

  Read the article

• Visual Studio 2010 Productivity Tips and Tricks-Part 2: Key Shortcuts

  - by ToStringTheory

  Ask anyone that knows me, and they will confirm that I hate the mouse.  This isn’t because I deny affection to objects that don’t look like their mammalian-named self, but rather for a much more simple and not-insane reason: I have terrible eyesight.  Introduction Thanks to a degenerative eye disease known as Choroideremia, I have learned to rely more on the keyboard which I can feel digital/static positions of keys relative to my fingers, than the much more analog/random position of the mouse.  Now, I would like to share some of the keyboard shortcuts with you now, as I believe that they not only increase my productivity, but yours as well once you know them (if you don’t already of course)...  I share one of my biggest tips for productivity in the conclusion at the end. Visual Studio Key Shortcuts Global Editor Shortcuts These are shortcuts that are available from almost any application running in Windows, however are many times forgotten. Shortcut Action Visual Studio 2010 Functionality Ctrl + X Cut This shortcut works without a selection. If nothing is selected, the entire line that the caret is on is cut from the editor. Ctrl + C Copy This shortcut works without a selection. If nothing is selected, the entire line that the caret is on is copied from the editor. Ctrl + V Paste If you copied an entire line by the method above, the data is pasted in the line above the current caret line. Ctrl + Shift + V Next Clipboard Element Cut/Copy multiple things, and then hit this combo repeatedly to switch to the next clipboard item when pasting. Ctrl + Backspace Delete Previous Will delete the previous word from the editor directly before the caret. If anything is selected, will just delete that. Ctrl + Del Delete Next Word Will delete the next word/space from the editor directly after the caret. If anything is selected, will just delete that. Shift + Del Delete Focused Line Will delete the line from the editor that the caret is on. If something is selected, will just delete that. Ctrl + ? or Ctrl + ? Left/Right by Word This will move the caret left or right by word or special character boundary. Holding Shift will also select the word. Ctrl + F Quick Find Either the Quick Find panel, or the search bar if you have the Productivity Power Tools installed. Ctrl + Shift + F Find in Solution Opens up the 'Find in Files' window, allowing you to search your solution, as well as using regex for pattern matching. F2 Rename File... While not debugging, selecting a file in the solution explorer\navigator and pressing F2 allows you to rename the selected file. Global Application Shortcuts These are shortcuts that are available from almost any application running in Windows, however are many times forgotten... Again... Shortcut Action Visual Studio 2010 Functionality Ctrl + N New File dialog Opens up the 'New File' dialog to add a new file to the current directory in the Solution\Project. Ctrl + O Open File dialog Opens up the 'Open File' dialog to open a file in the editor, not necessarily in the solution. Ctrl + S Save File dialog Saves the currently focused editor tab back to your HDD/SSD. Ctrl + Shift + S Save All... Quickly save all open/edited documents back to your disk. Ctrl + Tab Switch Panel\Tab Tapping this combo switches between tabs quickly. Holding down Ctrl when hitting tab will bring up a chooser window. Building Shortcuts These are shortcuts that are focused on building and running a solution. These are not usable when the IDE is in Debug mode, as the shortcut changes by context. Shortcut Action Visual Studio 2010 Functionality Ctrl + Shift + B Build Solution Starts a build process on the solution according to the current build configuration manager settings. Ctrl + Break Cancel a Building Solution Will cancel a build operation currently in progress. Good for long running builds when you think of one last change. F5 Start Debugging Will build the solution if needed and launch debugging according to the current configuration manager settings. Ctrl + F5 Start Without Debugger Will build the solution if needed and launch the startup project without attaching a debugger. Debugging Shortcuts These are shortcuts that are used when debugging a solution. Shortcut Action Visual Studio 2010 Functionality F5 Continue Execution Continues execution of code until the next breakpoint. Ctrl + Alt + Break Pause Execution Pauses the program execution. Shift + F5 Stop Debugging Stops the current debugging session. NOTE: Web apps will still continue processing after stopping the debugger. Keep this in mind if working on code such as credit card processing. Ctrl + Shift + F5 Restart Debugging Stops the current debugging session and restarts the debugging session from the beginning. F9 Place Breakpoint Toggles/Places a breakpoint in the editor on the current line. Set a breakpoint in condensed code by highlighting the statement first. F10 Step Over Statement When debugging, executes all code in methods/properties on the current line until the next line. F11 Step Into Statement When debugging, steps into a method call so you can walk through the code executed there (if available). Ctrl + Alt + I Immediate Window Open the Immediate Window to execute commands when execution is paused. Navigation Shortcuts These are shortcuts that are used for navigating in the IDE or editor panel. Shortcut Action Visual Studio 2010 Functionality F4 Properties Panel Opens the properties panel for the selected item in the editor/designer/solution navigator (context driven). F12 Go to Definition Press F12 with the caret on a member to navigate to its declaration. With the Productivity tools, Ctrl + Click works too. Ctrl + K Ctrl + T View Call Hierarchy View the call hierarchy of the member the caret is on. Great for going through n-tier solutions and interface implementations! Ctrl + Alt + B Breakpoint Window View the breakpoint window to manage breakpoints and their advanced options. Allows easy toggling of breakpoints. Ctrl + Alt + L Solution Navigator Open the solution explorer panel. Ctrl + Alt + O Output Window View the output window to see build\general output from Visual Studio. Ctrl + Alt + Enter Live Web Preview Only available with the Web Essential plugin. Launches the auto-updating Preview panel. Testing Shortcuts These are shortcuts that are used for running tests in the IDE. Please note, Visual Studio 2010 is all about context. If your caret is within a test method when you use one of these combinations, the combination will apply to that test. If your caret is within a test class, it will apply to that class. If the caret is outside of a test class, it will apply to all tests. Shortcut Action Visual Studio 2010 Functionality Ctrl + R T Run Test(s) Run all tests in the current context without a debugger attached. Breakpoints will not be stopped on. Ctrl + R Ctrl + T Run Test(s) (Debug) Run all tests in the current context with a debugger attached. This allows you to use breakpoints. Substitute A for T from the preceding combos to run/debug ALL tests in the current context. Substitute Y for T from the preceding combos to run/debug ALL impacted/covering tests for a method in the current context. Advanced Editor Shortcuts These are shortcuts that are used for more advanced editing in the editor window. Shortcut Action Visual Studio 2010 Functionality Shift + Alt + ? Shift + Alt + ? Multiline caret up/down Use this combo to edit multiple lines at once. Not too many uses for it, but once in a blue moon one comes along. Ctrl + Alt + Enter Insert Line Above Inserts a blank line above the line the caret is currently on. No need to be at end or start of line, so no cutting off words/code. Ctrl + K Ctrl + C Comment Selection Comments the current selection out of compilation. Ctrl + K Ctrl + U Uncomment Selection Uncomments the current selection into compilation. Ctrl + K Ctrl + D Format Document Automatically formats the document into a structured layout. Lines up nodes or code into columns intelligently. Alt + ? Alt + ? Code line up/down *Use this combo to move a line of code up or down quickly. Great for small rearrangements of code. *Requires the Productivity Power pack from Microsoft. Conclusion This list is by no means meant to be exhaustive, but these are the shortcuts I use regularly every hour/minute of the day. There are still 100s more in Visual Studio that you can discover through the configuration window, or by tooltips. Something that I started doing months ago seems to have interest in my office.. In my last post, I talked about how I hated a cluttered UI. One of the ways that I aimed to resolve that was by systematically cleaning up the toolbars week by week. First day, I removed ALL icons that I already knew shortcuts to, or would never use them (Undo in a toolbar?!). Then, every week from that point on, I make it a point to remove an icon/two from the toolbar and make an effort to remember its key combination. I gain extra space in the toolbar area, AND become more productive at the same time! I hope that you found this article interesting or at least somewhat informative.. Maybe a shortcut or two you didn't know. I know some of them seem trivial, but I often see people going to the edit menu for Copy/Paste... Thought a refresher might be helpful!

  Read the article

• Set-Cookie Headers getting stripped in ASP.NET HttpHandlers

  - by Rick Strahl

  Yikes, I ran into a real bummer of an edge case yesterday in one of my older low level handler implementations (for West Wind Web Connection in this case). Basically this handler is a connector for a backend Web framework that creates self contained HTTP output. An ASP.NET Handler captures the full output, and then shoves the result down the ASP.NET Response object pipeline writing out the content into the Response.OutputStream and seperately sending the HttpHeaders in the Response.Headers collection. The headers turned out to be the problem and specifically Http Cookies, which for some reason ended up getting stripped out in some scenarios. My handler works like this: Basically the HTTP response from the backend app would return a full set of HTTP headers plus the content. The ASP.NET handler would read the headers one at a time and then dump them out via Response.AppendHeader(). But I found that in some situations Set-Cookie headers sent along were simply stripped inside of the Http Handler. After a bunch of back and forth with some folks from Microsoft (thanks Damien and Levi!) I managed to pin this down to a very narrow edge scenario. It's easiest to demonstrate the problem with a simple example HttpHandler implementation. The following simulates the very much simplified output generation process that fails in my handler. Specifically I have a couple of headers including a Set-Cookie header and some output that gets written into the Response object.using System.Web; namespace wwThreads { public class Handler : IHttpHandler { /* NOTE: * * Run as a web.config set handler (see entry below) * * Best way is to look at the HTTP Headers in Fiddler * or Chrome/FireBug/IE tools and look for the * WWHTREADSID cookie in the outgoing Response headers * ( If the cookie is not there you see the problem! ) */ public void ProcessRequest(HttpContext context) { HttpRequest request = context.Request; HttpResponse response = context.Response; // If ClearHeaders is used Set-Cookie header gets removed! // if commented header is sent... response.ClearHeaders(); response.ClearContent(); // Demonstrate that other headers make it response.AppendHeader("RequestId", "asdasdasd"); // This cookie gets removed when ClearHeaders above is called // When ClearHEaders is omitted above the cookie renders response.AppendHeader("Set-Cookie", "WWTHREADSID=ThisIsThEValue; path=/"); // *** This always works, even when explicit // Set-Cookie above fails and ClearHeaders is called //response.Cookies.Add(new HttpCookie("WWTHREADSID", "ThisIsTheValue")); response.Write(@"Output was created.<hr/> Check output with Fiddler or HTTP Proxy to see whether cookie was sent."); } public bool IsReusable { get { return false; } } } } In order to see the problem behavior this code has to be inside of an HttpHandler, and specifically in a handler defined in web.config with: <add name=".ck_handler" path="handler.ck" verb="*" type="wwThreads.Handler" preCondition="integratedMode" /> Note: Oddly enough this problem manifests only when configured through web.config, not in an ASHX handler, nor if you paste that same code into an ASPX page or MVC controller. What's the problem exactly? The code above simulates the more complex code in my live handler that picks up the HTTP response from the backend application and then peels out the headers and sends them one at a time via Response.AppendHeader. One of the headers in my app can be one or more Set-Cookie. I found that the Set-Cookie headers were not making it into the Response headers output. Here's the Chrome Http Inspector trace: Notice, no Set-Cookie header in the Response headers! Now, running the very same request after removing the call to Response.ClearHeaders() command, the cookie header shows up just fine: As you might expect it took a while to track this down. At first I thought my backend was not sending the headers but after closer checks I found that indeed the headers were set in the backend HTTP response, and they were indeed getting set via Response.AppendHeader() in the handler code. Yet, no cookie in the output. In the simulated example the problem is this line:response.AppendHeader("Set-Cookie", "WWTHREADSID=ThisIsThEValue; path=/"); which in my live code is more dynamic ( ie. AppendHeader(token[0],token[1[]) )as it parses through the headers. Bizzaro Land: Response.ClearHeaders() causes Cookie to get stripped Now, here is where it really gets bizarre: The problem occurs only if: Response.ClearHeaders() was called before headers are added It only occurs in Http Handlers declared in web.config Clearly this is an edge of an edge case but of course - knowing my relationship with Mr. Murphy - I ended up running smack into this problem. So in the code above if you remove the call to ClearHeaders(), the cookie gets set!  Add it back in and the cookie is not there. If I run the above code in an ASHX handler it works. If I paste the same code (with a Response.End()) into an ASPX page, or MVC controller it all works. Only in the HttpHandler configured through Web.config does it fail! Cue the Twilight Zone Music. Workarounds As is often the case the fix for this once you know the problem is not too difficult. The difficulty lies in tracking inconsistencies like this down. Luckily there are a few simple workarounds for the Cookie issue. Don't use AppendHeader for Cookies The easiest and obvious solution to this problem is simply not use Response.AppendHeader() to set Cookies. Duh! Under normal circumstances in application level code there's rarely a reason to write out a cookie like this:response.AppendHeader("Set-Cookie", "WWTHREADSID=ThisIsThEValue; path=/"); but rather create the cookie using the Response.Cookies collection:response.Cookies.Add(new HttpCookie("WWTHREADSID", "ThisIsTheValue")); Unfortunately, in my case where I dynamically read headers from the original output and then dynamically  write header key value pairs back  programmatically into the Response.Headers collection, I actually don't look at each header specifically so in my case the cookie is just another header. My first thought was to simply trap for the Set-Cookie header and then parse out the cookie and create a Cookie object instead. But given that cookies can have a lot of different options this is not exactly trivial, plus I don't really want to fuck around with cookie values which can be notoriously brittle. Don't use Response.ClearHeaders() The real mystery in all this is why calling Response.ClearHeaders() prevents a cookie value later written with Response.AppendHeader() to fail. I fired up Reflector and took a quick look at System.Web and HttpResponse.ClearHeaders. There's all sorts of resetting going on but nothing that seems to indicate that headers should be removed later on in the request. The code in ClearHeaders() does access the HttpWorkerRequest, which is the low level interface directly into IIS, and so I suspect it's actually IIS that's stripping the headers and not ASP.NET, but it's hard to know. Somebody from Microsoft and the IIS team would have to comment on that. In my application it's probably safe to simply skip ClearHeaders() in my handler. The ClearHeaders/ClearContent was mainly for safety but after reviewing my code there really should never be a reason that headers would be set prior to this method firing. However, if for whatever reason headers do need to be cleared, it's easy enough to manually clear the headers out:private void RemoveHeaders(HttpResponse response) { List<string> headers = new List<string>(); foreach (string header in response.Headers) { headers.Add(header); } foreach (string header in headers) { response.Headers.Remove(header); } response.Cookies.Clear(); } Now I can replace the call the Response.ClearHeaders() and I don't get the funky side-effects from Response.ClearHeaders(). Summary I realize this is a total edge case as this occurs only in HttpHandlers that are manually configured. It looks like you'll never run into this in any of the higher level ASP.NET frameworks or even in ASHX handlers - only web.config defined handlers - which is really, really odd. After all those frameworks use the same underlying ASP.NET architecture. Hopefully somebody from Microsoft has an idea what crazy dependency was triggered here to make this fail. IAC, there are workarounds to this should you run into it, although I bet when you do run into it, it'll likely take a bit of time to find the problem or even this post in a search because it's not easily to correlate the problem to the solution. It's quite possible that more than cookies are affected by this behavior. Searching for a solution I read a few other accounts where headers like Referer were mysteriously disappearing, and it's possible that something similar is happening in those cases. Again, extreme edge case, but I'm writing this up here as documentation for myself and possibly some others that might have run into this. © Rick Strahl, West Wind Technologies, 2005-2012Posted in ASP.NET   IIS7   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

  Read the article

• Guest Post: Using IronRuby and .NET to produce the &lsquo;Hello World of WPF&rsquo;

  - by Eric Nelson

  [You might want to also read other GuestPosts on my blog – or contribute one?] On the 26th and 27th of March (2010) myself and Edd Morgan of Microsoft will be popping along to the Scottish Ruby Conference. I dabble with Ruby and I am a huge fan whilst Edd is a “proper Ruby developer”. Hence I asked Edd if he was interested in creating a guest post or two for my blog on IronRuby. This is the second of those posts. If you should stumble across this post and happen to be attending the Scottish Ruby Conference, then please do keep a look out for myself and Edd. We would both love to chat about all things Ruby and IronRuby. And… we should have (if Amazon is kind) a few books on IronRuby with us at the conference which will need to find a good home. This is me and Edd and … the book: Order on Amazon: http://bit.ly/ironrubyunleashed Using IronRuby and .NET to produce the ‘Hello World of WPF’ In my previous post I introduced, to a minor extent, IronRuby. I expanded a little on the basics of by getting a Rails app up-and-running on this .NET implementation of the Ruby language — but there wasn't much to it! So now I would like to go from simply running a pre-existing project under IronRuby to developing a whole new application demonstrating the seamless interoperability between IronRuby and .NET. In particular, we'll be using WPF (Windows Presentation Foundation) — the component of the .NET Framework stack used to create rich media and graphical interfaces. Foundations of WPF To reiterate, WPF is the engine in the .NET Framework responsible for rendering rich user interfaces and other media. It's not the only collection of libraries in the framework with the power to do this — Windows Forms does the trick, too — but it is the most powerful and flexible. Put simply, WPF really excels when you need to employ eye candy. It's all about creating impact. Whether you're presenting a document, video, a data entry form, some kind of data visualisation (which I am most hopeful for, especially in terms of IronRuby - more on that later) or chaining all of the above with some flashy animations, you're likely to find that WPF gives you the most power when developing any of these for a Windows target. Let's demonstrate this with an example. I give you what I like to consider the 'hello, world' of WPF applications: the analogue clock. Today, over my lunch break, I created a WPF-based analogue clock using IronRuby... Any normal person would have just looked at their watch. - Twitter The Sample Application: Click here to see this sample in full on GitHub. Using Windows Presentation Foundation from IronRuby to create a Clock class Invoking the Clock class   Gives you The above is by no means perfect (it was a lunch break), but I think it does the job of illustrating IronRuby's interoperability with WPF using a familiar data visualisation. I'm sure you'll want to dissect the code yourself, but allow me to step through the important bits. (By the way, feel free to run this through ir first to see what actually happens). Now we're using IronRuby - unlike my previous post where we took pure Ruby code and ran it through ir, the IronRuby interpreter, to demonstrate compatibility. The main thing of note is the very distinct parallels between .NET namespaces and Ruby modules, .NET classes and Ruby classes. I guess there's not much to say about it other than at this point, you may as well be working with a purely Ruby graphics-drawing library. You're instantiating .NET objects, but you're doing it with the standard Ruby .new method you know from Ruby as Object#new — although, the root object of all your IronRuby objects isn't actually Object, it's System.Object. You're calling methods on these objects (and classes, for example in the call to System.Windows.Controls.Canvas.SetZIndex()) using the underscored, lowercase convention established for the Ruby language. The integration is so seamless. The fact that you're using a dynamic language on top of .NET's CLR is completely abstracted from you, allowing you to just build your software. A Brief Note on Events Events are a big part of developing client applications in .NET as well as under every other environment I can think of. In case you aren't aware, event-driven programming is essentially the practice of telling your code to call a particular method, or other chunk of code (a delegate) when something happens at an unpredictable time. You can never predict when a user is going to click a button, move their mouse or perform any other kind of input, so the advent of the GUI is what necessitated event-driven programming. This is where one of my favourite aspects of the Ruby language, blocks, can really help us. In traditional C#, for instance, you may subscribe to an event (assign a block of code to execute when an event occurs) in one of two ways: by passing a reference to a named method, or by providing an anonymous code block. You'd be right for seeing the parallel here with Ruby's concept of blocks, Procs and lambdas. As demonstrated at the very end of this rather basic script, we are using .NET's System.Timers.Timer to (attempt to) update the clock every second (I know it's probably not the best way of doing this, but for example's sake). Note: Diverting a little from what I said above, the ticking of a clock is very predictable, yet we still use the event our Timer throws to do this updating as one of many ways to perform that task outside of the main thread. You'll see that all that's needed to assign a block of code to be triggered on an event is to provide that block to the method of the name of the event as it is known to the CLR. This drawback to this is that it only allows the delegation of one code block to each event. You may use the add method to subscribe multiple handlers to that event - pushing that to the end of a queue. Like so: def tick puts "tick tock" end timer.elapsed.add method(:tick) timer.elapsed.add proc { puts "tick tock" } tick_handler = lambda { puts "tick tock" } timer.elapsed.add(tick_handler)   The ability to just provide a block of code as an event handler helps IronRuby towards that very important term I keep throwing around; low ceremony. Anonymous methods are, of course, available in other more conventional .NET languages such as C# and VB but, as usual, feel ever so much more elegant and natural in IronRuby. Note: Whether it's a named method or an anonymous chunk o' code, the block you delegate to the handling of an event can take arguments - commonly, a sender object and some args. Another Brief Note on Verbosity Personally, I don't mind verbose chaining of references in my code as long as it doesn't interfere with performance - as evidenced in the example above. While I love clean code, there's a certain feeling of safety that comes with the terse explicitness of long-winded addressing and the describing of objects as opposed to ambiguity (not unlike this sentence). However, when working with IronRuby, even I grow tired of typing System::Whatever::Something. Some people enjoy simply assuming namespaces and forgetting about them, regardless of the language they're using. Don't worry, IronRuby has you covered. It is completely possible to, with a call to include, bring the contents of a .NET-converted module into context of your IronRuby code - just as you would if you wanted to bring in an 'organic' Ruby module. To refactor the style of the above example, I could place the following at the top of my Clock class: class Clock include System::Windows::Shape include System::Windows::Media include System::Windows::Threading # and so on...   And by doing so, reduce calls to System::Windows::Shapes::Ellipse.new to simply Ellipse.new or references to System::Windows::Threading::DispatcherPriority.Render to a friendlier DispatcherPriority.Render. Conclusion I hope by now you can understand better how IronRuby interoperates with .NET and how you can harness the power of the .NET framework with the dynamic nature and elegant idioms of the Ruby language. The manner and parlance of Ruby that makes it a joy to work with sets of data is, of course, present in IronRuby — couple that with WPF's capability to produce great graphics quickly and easily, and I hope you can visualise the possibilities of data visualisation using these two things. Using IronRuby and WPF together to create visual representations of data and infographics is very exciting to me. Although today, with this project, we're only presenting one simple piece of information - the time - the potential is much grander. My day-to-day job is centred around software development and UI design, specifically in the realm of healthcare, and if you were to pay a visit to our office you would behold, directly above my desk, a large plasma TV with a constantly rotating, animated slideshow of charts and infographics to help members of our team do their jobs. It's an app powered by WPF which never fails to spark some conversation with visitors whose gaze has been hooked. If only it was written in IronRuby, the pleasantly low ceremony and reduced pre-processing time for my brain would have helped greatly. Edd Morgan blog Related Links: Getting PhP and Ruby working on Windows Azure and SQL Azure

  Read the article

• C#/.NET Little Wonders: Tuples and Tuple Factory Methods

  - by James Michael Hare

  Once again, in this series of posts I look at the parts of the .NET Framework that may seem trivial, but can really help improve your code by making it easier to write and maintain.  This week, we look at the System.Tuple class and the handy factory methods for creating a Tuple by inferring the types. What is a Tuple? The System.Tuple is a class that tends to inspire a reaction in one of two ways: love or hate.  Simply put, a Tuple is a data structure that holds a specific number of items of a specific type in a specific order.  That is, a Tuple<int, string, int> is a tuple that contains exactly three items: an int, followed by a string, followed by an int.  The sequence is important not only to distinguish between two members of the tuple with the same type, but also for comparisons between tuples.  Some people tend to love tuples because they give you a quick way to combine multiple values into one result.  This can be handy for returning more than one value from a method (without using out or ref parameters), or for creating a compound key to a Dictionary, or any other purpose you can think of.  They can be especially handy when passing a series of items into a call that only takes one object parameter, such as passing an argument to a thread's startup routine.  In these cases, you do not need to define a class, simply create a tuple containing the types you wish to return, and you are ready to go? On the other hand, there are some people who see tuples as a crutch in object-oriented design.  They may view the tuple as a very watered down class with very little inherent semantic meaning.  As an example, what if you saw this in a piece of code: 1: var x = new Tuple<int, int>(2, 5); What are the contents of this tuple?  If the tuple isn't named appropriately, and if the contents of each member are not self evident from the type this can be a confusing question.  The people who tend to be against tuples would rather you explicitly code a class to contain the values, such as: 1: public sealed class RetrySettings 2: { 3: public int TimeoutSeconds { get; set; } 4: public int MaxRetries { get; set; } 5: } Here, the meaning of each int in the class is much more clear, but it's a bit more work to create the class and can clutter a solution with extra classes. So, what's the correct way to go?  That's a tough call.  You will have people who will argue quite well for one or the other.  For me, I consider the Tuple to be a tool to make it easy to collect values together easily.  There are times when I just need to combine items for a key or a result, in which case the tuple is short lived and so the meaning isn't easily lost and I feel this is a good compromise.  If the scope of the collection of items, though, is more application-wide I tend to favor creating a full class. Finally, it should be noted that tuples are immutable.  That means they are assigned a value at construction, and that value cannot be changed.  Now, of course if the tuple contains an item of a reference type, this means that the reference is immutable and not the item referred to. Tuples from 1 to N Tuples come in all sizes, you can have as few as one element in your tuple, or as many as you like.  However, since C# generics can't have an infinite generic type parameter list, any items after 7 have to be collapsed into another tuple, as we'll show shortly. So when you declare your tuple from sizes 1 (a 1-tuple or singleton) to 7 (a 7-tuple or septuple), simply include the appropriate number of type arguments: 1: // a singleton tuple of integer 2: Tuple<int> x; 3:  4: // or more 5: Tuple<int, double> y; 6:  7: // up to seven 8: Tuple<int, double, char, double, int, string, uint> z; Anything eight and above, and we have to nest tuples inside of tuples.  The last element of the 8-tuple is the generic type parameter Rest, this is special in that the Tuple checks to make sure at runtime that the type is a Tuple.  This means that a simple 8-tuple must nest a singleton tuple (one of the good uses for a singleton tuple, by the way) for the Rest property. 1: // an 8-tuple 2: Tuple<int, int, int, int, int, double, char, Tuple<string>> t8; 3:  4: // an 9-tuple 5: Tuple<int, int, int, int, double, int, char, Tuple<string, DateTime>> t9; 6:  7: // a 16-tuple 8: Tuple<int, int, int, int, int, int, int, Tuple<int, int, int, int, int, int, int, Tuple<int,int>>> t14; Notice that on the 14-tuple we had to have a nested tuple in the nested tuple.  Since the tuple can only support up to seven items, and then a rest element, that means that if the nested tuple needs more than seven items you must nest in it as well.  Constructing tuples Constructing tuples is just as straightforward as declaring them.  That said, you have two distinct ways to do it.  The first is to construct the tuple explicitly yourself: 1: var t3 = new Tuple<int, string, double>(1, "Hello", 3.1415927); This creates a triple that has an int, string, and double and assigns the values 1, "Hello", and 3.1415927 respectively.  Make sure the order of the arguments supplied matches the order of the types!  Also notice that we can't half-assign a tuple or create a default tuple.  Tuples are immutable (you can't change the values once constructed), so thus you must provide all values at construction time. Another way to easily create tuples is to do it implicitly using the System.Tuple static class's Create() factory methods.  These methods (much like C++'s std::make_pair method) will infer the types from the method call so you don't have to type them in.  This can dramatically reduce the amount of typing required especially for complex tuples! 1: // this 4-tuple is typed Tuple<int, double, string, char> 2: var t4 = Tuple.Create(42, 3.1415927, "Love", 'X'); Notice how much easier it is to use the factory methods and infer the types?  This can cut down on typing quite a bit when constructing tuples.  The Create() factory method can construct from a 1-tuple (singleton) to an 8-tuple (octuple), which of course will be a octuple where the last item is a singleton as we described before in nested tuples. Accessing tuple members Accessing a tuple's members is simplicity itself… mostly.  The properties for accessing up to the first seven items are Item1, Item2, …, Item7.  If you have an octuple or beyond, the final property is Rest which will give you the nested tuple which you can then access in a similar matter.  Once again, keep in mind that these are read-only properties and cannot be changed. 1: // for septuples and below, use the Item properties 2: var t1 = Tuple.Create(42, 3.14); 3:  4: Console.WriteLine("First item is {0} and second is {1}", 5: t1.Item1, t1.Item2); 6:  7: // for octuples and above, use Rest to retrieve nested tuple 8: var t9 = new Tuple<int, int, int, int, int, int, int, 9: Tuple<int, int>>(1,2,3,4,5,6,7,Tuple.Create(8,9)); 10:  11: Console.WriteLine("The 8th item is {0}", t9.Rest.Item1); Tuples are IStructuralComparable and IStructuralEquatable Most of you know about IComparable and IEquatable, what you may not know is that there are two sister interfaces to these that were added in .NET 4.0 to help support tuples.  These IStructuralComparable and IStructuralEquatable make it easy to compare two tuples for equality and ordering.  This is invaluable for sorting, and makes it easy to use tuples as a compound-key to a dictionary (one of my favorite uses)! Why is this so important?  Remember when we said that some folks think tuples are too generic and you should define a custom class?  This is all well and good, but if you want to design a custom class that can automatically order itself based on its members and build a hash code for itself based on its members, it is no longer a trivial task!  Thankfully the tuple does this all for you through the explicit implementations of these interfaces. For equality, two tuples are equal if all elements are equal between the two tuples, that is if t1.Item1 == t2.Item1 and t1.Item2 == t2.Item2, and so on.  For ordering, it's a little more complex in that it compares the two tuples one at a time starting at Item1, and sees which one has a smaller Item1.  If one has a smaller Item1, it is the smaller tuple.  However if both Item1 are the same, it compares Item2 and so on. For example: 1: var t1 = Tuple.Create(1, 3.14, "Hi"); 2: var t2 = Tuple.Create(1, 3.14, "Hi"); 3: var t3 = Tuple.Create(2, 2.72, "Bye"); 4:  5: // true, t1 == t2 because all items are == 6: Console.WriteLine("t1 == t2 : " + t1.Equals(t2)); 7:  8: // false, t1 != t2 because at least one item different 9: Console.WriteLine("t2 == t2 : " + t2.Equals(t3)); The actual implementation of IComparable, IEquatable, IStructuralComparable, and IStructuralEquatable is explicit, so if you want to invoke the methods defined there you'll have to manually cast to the appropriate interface: 1: // true because t1.Item1 < t3.Item1, if had been same would check Item2 and so on 2: Console.WriteLine("t1 < t3 : " + (((IComparable)t1).CompareTo(t3) < 0)); So, as I mentioned, the fact that tuples are automatically equatable and comparable (provided the types you use define equality and comparability as needed) means that we can use tuples for compound keys in hashing and ordering containers like Dictionary and SortedList: 1: var tupleDict = new Dictionary<Tuple<int, double, string>, string>(); 2:  3: tupleDict.Add(t1, "First tuple"); 4: tupleDict.Add(t2, "Second tuple"); 5: tupleDict.Add(t3, "Third tuple"); Because IEquatable defines GetHashCode(), and Tuple's IStructuralEquatable implementation creates this hash code by combining the hash codes of the members, this makes using the tuple as a complex key quite easy!  For example, let's say you are creating account charts for a financial application, and you want to cache those charts in a Dictionary based on the account number and the number of days of chart data (for example, a 1 day chart, 1 week chart, etc): 1: // the account number (string) and number of days (int) are key to get cached chart 2: var chartCache = new Dictionary<Tuple<string, int>, IChart>(); Summary The System.Tuple, like any tool, is best used where it will achieve a greater benefit.  I wouldn't advise overusing them, on objects with a large scope or it can become difficult to maintain.  However, when used properly in a well defined scope they can make your code cleaner and easier to maintain by removing the need for extraneous POCOs and custom property hashing and ordering. They are especially useful in defining compound keys to IDictionary implementations and for returning multiple values from methods, or passing multiple values to a single object parameter. Tweet Technorati Tags: C#,.NET,Tuple,Little Wonders

  Read the article

• Web API, JavaScript, Chrome &amp; Cross-Origin Resource Sharing

  - by Brian Lanham

  The team spent much of the week working through this issues related to Chrome running on Windows 8 consuming cross-origin resources using Web API.  We thought it was resolved on day 2 but it resurfaced the next day.  We definitely resolved it today though.  I believe I do not fully understand the situation but I am going to explain what I know in an effort to help you avoid and/or resolve a similar issue. References We referenced many sources during our trial-and-error troubleshooting.  These are the links we reference in order of applicability to the solution: Zoiner Tejada JavaScript and other material from -> http://www.devproconnections.com/content1/topic/microsoft-azure-cors-141869/catpath/windows-azure-platform2/page/3 WebDAV Where I learned about “Accept” –>  http://www-jo.se/f.pfleger/cors-and-iis? IT Hit Tells about NOT using ‘*’ –> http://www.webdavsystem.com/ajax/programming/cross_origin_requests Carlos Figueira Sample back-end code (newer) –> http://code.msdn.microsoft.com/windowsdesktop/Implementing-CORS-support-a677ab5d (older version) –> http://code.msdn.microsoft.com/CORS-support-in-ASPNET-Web-01e9980a   Background As a measure of protection, Web designers (W3C) and implementers (Google, Microsoft, Mozilla) made it so that a request, especially a JSON request (but really any URL), sent from one domain to another will only work if the requestee “knows” about the requester and allows requests from it. So, for example, if you write a ASP.NET MVC Web API service and try to consume it from multiple apps, the browsers used may (will?) indicate that you are not allowed by showing an “Access-Control-Allow-Origin” error indicating the requester is not allowed to make requests. Internet Explorer (big surprise) is the odd-hair-colored step-child in this mix. It seems that running locally at least IE allows this for development purposes.  Chrome and Firefox do not.  In fact, Chrome is quite restrictive.  Notice the images below. IE shows data (a tabular view with one row for each day of a week) while Chrome does not (trust me, neither does Firefox).  Further, the Chrome developer console shows an XmlHttpRequest (XHR) error. Screen captures from IE (left) and Chrome (right). Note that Chrome does not display data and the console shows an XHR error. Why does this happen? The Web browser submits these requests and processes the responses and each browser is different. Okay, so, IE is probably the only one that’s truly different.  However, Chrome has a specific process of performing a “pre-flight” check to make sure the service can respond to an “Access-Control-Allow-Origin” or Cross-Origin Resource Sharing (CORS) request.  So basically, the sequence is, if I understand correctly:  1)Page Loads –> 2)JavaScript Request Processed by Browser –> 3)Browsers Prepares to Submit Request –> 4)[Chrome] Browser Submits Pre-Flight Request –> 5)Server Responds with HTTP 200 –> 6)Browser Submits Request –> 7)Server Responds with Data –> 8)Page Shows Data This situation occurs for both GET and POST methods.  Typically, GET methods are called with query string parameters so there is no data posted.  Instead, the requesting domain needs to be permitted to request data but generally nothing more is required.  POSTs on the other hand send form data.  Therefore, more configuration is required (you’ll see the configuration below).  AJAX requests are not friendly with this (POSTs) either because they don’t post in a form. How to fix it. The team went through many iterations of self-hair removal and we think we finally have a working solution.  The trial-and-error approach eventually worked and we referenced many sources for the information.  I indicate those references above.  There are basically three (3) tasks needed to make this work. Assumptions: You are using Visual Studio, Web API, JavaScript, and have Cross-Origin Resource Sharing, and several browsers. 1. Configure the client Joel Cochran centralized our “cors-oriented” JavaScript (from here). There are two calls including one for GET and one for POST function(url, data, callback) {             console.log(data);             $.support.cors = true;             var jqxhr = $.post(url, data, callback, "json")                 .error(function(jqXhHR, status, errorThrown) {                     if ($.browser.msie && window.XDomainRequest) {                         var xdr = new XDomainRequest();                         xdr.open("post", url);                         xdr.onload = function () {                             if (callback) {                                 callback(JSON.parse(this.responseText), 'success');                             }                         };                         xdr.send(data);                     } else {                         console.log(">" + jqXhHR.status);                         alert("corsAjax.post error: " + status + ", " + errorThrown);                     }                 });         }; The GET CORS JavaScript function (credit to Zoiner Tejada) function(url, callback) {             $.support.cors = true;             var jqxhr = $.get(url, null, callback, "json")                 .error(function(jqXhHR, status, errorThrown) {                     if ($.browser.msie && window.XDomainRequest) {                         var xdr = new XDomainRequest();                         xdr.open("get", url);                         xdr.onload = function () {                             if (callback) {                                 callback(JSON.parse(this.responseText), 'success');                             }                         };                         xdr.send();                     } else {                         alert("CORS is not supported in this browser or from this origin.");                     }                 });         }; The POST CORS JavaScript function (credit to Zoiner Tejada) Now you need to call these functions to get and post your data (instead of, say, using $.Ajax). Here is a GET example: corsAjax.get(url, function(data) { if (data !== null && data.length !== undefined) { // do something with data } }); And here is a POST example: corsAjax.post(url, item); Simple…except…you’re not done yet. 2. Change Web API Controllers to Allow CORS There are actually two steps here.  Do you remember above when we mentioned the “pre-flight” check?  Chrome actually asks the server if it is allowed to ask it for cross-origin resource sharing access.  So you need to let the server know it’s okay.  This is a two-part activity.  a) Add the appropriate response header Access-Control-Allow-Origin, and b) permit the API functions to respond to various methods including GET, POST, and OPTIONS.  OPTIONS is the method that Chrome and other browsers use to ask the server if it can ask about permissions.  Here is an example of a Web API controller thus decorated: NOTE: You’ll see a lot of references to using “*” in the header value.  For security reasons, Chrome does NOT recognize this is valid. [HttpHeader("Access-Control-Allow-Origin", "http://localhost:51234")] [HttpHeader("Access-Control-Allow-Credentials", "true")] [HttpHeader("Access-Control-Allow-Methods", "ACCEPT, PROPFIND, PROPPATCH, COPY, MOVE, DELETE, MKCOL, LOCK, UNLOCK, PUT, GETLIB, VERSION-CONTROL, CHECKIN, CHECKOUT, UNCHECKOUT, REPORT, UPDATE, CANCELUPLOAD, HEAD, OPTIONS, GET, POST")] [HttpHeader("Access-Control-Allow-Headers", "Accept, Overwrite, Destination, Content-Type, Depth, User-Agent, X-File-Size, X-Requested-With, If-Modified-Since, X-File-Name, Cache-Control")] [HttpHeader("Access-Control-Max-Age", "3600")] public abstract class BaseApiController : ApiController {     [HttpGet]     [HttpOptions]     public IEnumerable<foo> GetFooItems(int id)     {         return foo.AsEnumerable();     }     [HttpPost]     [HttpOptions]     public void UpdateFooItem(FooItem fooItem)     {         // NOTE: The fooItem object may or may not         // (probably NOT) be set with actual data.         // If not, you need to extract the data from         // the posted form manually.         if (fooItem.Id == 0) // However you check for default...         {             // We use NewtonSoft.Json.             string jsonString = context.Request.Form.GetValues(0)[0].ToString();             Newtonsoft.Json.JsonSerializer js = new Newtonsoft.Json.JsonSerializer();             fooItem = js.Deserialize<FooItem>(new Newtonsoft.Json.JsonTextReader(new System.IO.StringReader(jsonString)));         }         // Update the set fooItem object.     } } Please note a few specific additions here: * The header attributes at the class level are required.  Note all of those methods and headers need to be specified but we find it works this way so we aren’t touching it. * Web API will actually deserialize the posted data into the object parameter of the called method on occasion but so far we don’t know why it does and doesn’t. * [HttpOptions] is, again, required for the pre-flight check. * The “Access-Control-Allow-Origin” response header should NOT NOT NOT contain an ‘*’. 3. Headers and Methods and Such We had most of this code in place but found that Chrome and Firefox still did not render the data.  Interestingly enough, Fiddler showed that the GET calls succeeded and the JSON data is returned properly.  We learned that among the headers set at the class level, we needed to add “ACCEPT”.  Note that I accidentally added it to methods and to headers.  Adding it to methods worked but I don’t know why.  We added it to headers also for good measure. [HttpHeader("Access-Control-Allow-Methods", "ACCEPT, PROPFIND, PROPPA... [HttpHeader("Access-Control-Allow-Headers", "Accept, Overwrite, Destin... Next Steps That should do it.  If it doesn’t let us know.  What to do next?  * Don’t hardcode the allowed domains.  Note that port numbers and other domain name specifics will cause problems and must be specified.  If this changes do you really want to deploy updated software?  Consider Miguel Figueira’s approach in the following link to writing a custom HttpHeaderAttribute class that allows you to specify the domain names and then you can do it dynamically.  There are, of course, other ways to do it dynamically but this is a clean approach. http://code.msdn.microsoft.com/windowsdesktop/Implementing-CORS-support-a677ab5d

  Read the article

• Getting HAPROXY to redirect http to https in users browser session

  - by Jon

  We are currently using a Internet cloud provider to host our SaaS platform. The platform consists of a Firewall - Cloud Provider SLB - - Apache Web Server - HAPROXY SLB - Liferay Platform We have had to use HAPROXY because of an issue with the cloud providers SLB that meant we were unable to use it for load balancing the Liferay platform applications. I have implemented HAPROXY in our secure tier and that seems to do the trick of load balancing the requests quite adequately. However during testing we encountered a functional issue whereby selecting a sub-menu from the web portal resulted in the application hanging, using an http analyser we saw that the request being passed back to the users browser was in http, from discussing this with the software vendor it transpires that the Liferay application has some hard-coded http links, and that other customers have worked around this by using physical NLB's such as F5 and redirecting the http traffic to https. The entry in the HAPROXY logs reads: haproxy[2717]: haproxy[2717]: <Apache Web Agent>:37957 [11/Apr/2013:08:07:00.128] http-uapi uapi/<ServerName> 0/0/0/9/10 200 4912 - - ---- 4/2/1/2/0 0/0 "GET /servicedesk/controller?docommand=renderradform&!key=esd_sfb001_frm_feedback_forms_list&isportalintegratedmode=true&USR=joe.bloggs%40gmail.com&_dc=1365667773097&redirecturl=controller%3Fdocommand%3Drenderbody%26%21key%3DESD_SFB001_FRM_FEEDBACK_FORMS_LIST%26isportalintegratedmode%3Dtrue&sso_token=ALiYv2UqzLsAhSw1ZchRDlCHlq44Bhj9&ONERROR=%2Fweb%2Fjsp%2Fapps%2Fportal-integration-error.jsp&itype=login&slicetoken=NW51O%242aRo%2C_Zz%2476P_9DTtnFmz6%28bhk&AUTOFORWARDURL=controller%3Fdocommand%3Drenderbody%26%21key%3DESD_SFB001_FRM_FEEDBACK_FORMS_LIST%26isportalintegratedmode%3Dtrue&LOGINPAGE=https%3A%2F%2F<FQDN of Web Portal>%2Fweb%2F4732cf01-82c3-4bc5-b6c9-552253e672cf%2Fworkflow-tools&appid=1&!uid=1&!redownloadToken=7.0.3.1.1363611301.0&userlocale=en_US&!datechanged=2012-05-18%2015:05:31.38 HTTP/1.1" :37957 [11/Apr/2013:08:07:00.128] http-uapi uapi/<ServerName> 0/0/0/9/10 200 4912 - - ---- 4/2/1/2/0 0/0 "GET /servicedesk/controller?docommand=renderradform&!key=esd_sfb001_frm_feedback_forms_list&isportalintegratedmode=true&USR=joe.bloggs%40gmail.com&_dc=1365667773097&redirecturl=controller%3Fdocommand%3Drenderbody%26%21key%3DESD_SFB001_FRM_FEEDBACK_FORMS_LIST%26isportalintegratedmode%3Dtrue&sso_token=ALiYv2UqzLsAhSw1ZchRDlCHlq44Bhj9&ONERROR=%2Fweb%2Fjsp%2Fapps%2Fportal-integration-error.jsp&itype=login&slicetoken=NW51O%242aRo%2C_Zz%2476P_9DTtnFmz6%28bhk&AUTOFORWARDURL=controller%3Fdocommand%3Drenderbody%26%21key%3DESD_SFB001_FRM_FEEDBACK_FORMS_LIST%26isportalintegratedmode%3Dtrue&LOGINPAGE=https%3A%2F%2F<FQDN of Web Portal>%2Fweb%2F4732cf01-82c3-4bc5-b6c9-552253e672cf%2Fworkflow-tools&appid=1&!uid=1&!redownloadToken=7.0.3.1.1363611301.0&userlocale=en_US&!datechanged=2012-05-18%2015:05:31.38 HTTP/1.1" The corresponding HTTP browser entry shows: http://<FQDN of ServiceDesk>/servicedesk/controller?docommand=renderradform&!key=esd_org019_frm_contact_list&isportalintegratedmode=true&USR=joe.bloggs%40gmail.com&_dc=1365665987887&redirecturl=controller%3Fdocommand%3Drenderbody%26%21key%3DESD_ORG019_FRM_CONTACT_LIST%26isportalintegratedmode%3Dtrue&sso_token=3NxsXYORMPp32SwL8ftVUCMH2QdWLH82&ONERROR=%2Fweb%2Fjsp%2Fapps%2Fportal-integration-error.jsp&itype=login&slicetoken=NW51O%242aRo%2C_Zz%2476P_9DTtnFmz6%28bhk&AUTOFORWARDURL=controller%3Fdocommand%3Drenderbody%26%21key%3DESD_ORG019_FRM_CONTACT_LIST%26isportalintegratedmode%3Dtrue&LOGINPAGE=https%3A%2F%2F<FQDN of Web Portal>>%2Fweb%2F4732cf01-82c3-4bc5-b6c9-552253e672cf%2Fapplication-setup&appid=1&!uid=1&!redownloadToken=7.0.3.1.1363611301.0&userlocale=en_US&!datechanged=2012-10-26%2019:00:25.08 From reading through the forums and other sites it looks like we should be use to use HAPROXY to redirect the traffic to https, but try as I might I cant get it to work. This is our HAPROXY configuration: global log 127.0.0.1 local2 chroot /var/lib/haproxy pidfile /var/run/haproxy.pid maxconn 4000 user haproxy group haproxy daemon stats socket /var/lib/haproxy/stats defaults mode http log global option httplog option dontlognull option http-server-close option forwardfor except 127.0.0.0/8 option redispatch retries 3 timeout http-request 10s timeout queue 1m timeout connect 10s timeout client 1m timeout server 1m timeout http-keep-alive 10s timeout check 10s maxconn 3000 frontend http-openfire bind *:7070 default_backend openfire backend openfire balance roundrobin server <serverName> <IPv4 Address>:7070 check server <serverName> <IPv4 Address>:7070 check frontend http-uapi bind *:7080 default_backend uapi backend uapi balance roundrobin server <serverName> <IPv4 Address>:7080 check server <serverName> <IPv4 Address>:7080 check frontend http-sec bind *:8080 default_backend sec backend sec balance roundrobin server <serverName> <IPv4 Address>:8080 check server <serverName> <IPv4 Address>:8080 check frontend http-wall bind *:9080 default_backend wall backend wall balance roundrobin server <serverName> <IPv4 Address>:9080 check server <serverName> <IPv4 Address>:9080 check frontend http-xmpp bind *:9090 default_backend xmpp backend xmpp balance roundrobin server <serverName> <IPv4 Address>:9090 check server <serverName> <IPv4 Address>:9090 check frontend http-aim bind *:10080 default_backend aim backend aim balance roundrobin server <serverName> <IPv4 Address>:10080 check server <serverName> <IPv4 Address>:10080 check frontend http-servicedesk bind *:8081 default_backend servicedesk backend servicedesk balance roundrobin server <serverName> <IPv4 Address>:8081 check server <serverName> <IPv4 Address>:8081 check listen stats :1936 mode http stats enable stats hide-version stats realm Haproxy\ Statistics stats uri / stats auth haproxy:<Password> I have tried following the articles listed posted on http://stackoverflow.com/questions/13227544/haproxy-redirecting-http-to-https-ssl and http://parsnips.net/haproxy-http-to-https-redirect/ but that hasn't made any difference. Am I on the right track with this or are we trying to achieve the impossible?, I'm hoping I'm just being an idiot and one of you good people can point me in the right direction.

  Read the article

• Unable to cast transparent proxy to type &lt;type&gt;

  - by Rick Strahl

  This is not the first time I've run into this wonderful error while creating new AppDomains in .NET and then trying to load types and access them across App Domains. In almost all cases the problem I've run into with this error the problem comes from the two AppDomains involved loading different copies of the same type. Unless the types match exactly and come exactly from the same assembly the typecast will fail. The most common scenario is that the types are loaded from different assemblies - as unlikely as that sounds. An Example of Failure To give some context, I'm working on some old code in Html Help Builder that creates a new AppDomain in order to parse assembly information for documentation purposes. I create a new AppDomain in order to load up an assembly process it and then immediately unload it along with the AppDomain. The AppDomain allows for unloading that otherwise wouldn't be possible as well as isolating my code from the assembly that's being loaded. The process to accomplish this is fairly established and I use it for lots of applications that use add-in like functionality - basically anywhere where code needs to be isolated and have the ability to be unloaded. My pattern for this is: Create a new AppDomain Load a Factory Class into the AppDomain Use the Factory Class to load additional types from the remote domain Here's the relevant code from my TypeParserFactory that creates a domain and then loads a specific type - TypeParser - that is accessed cross-AppDomain in the parent domain:public class TypeParserFactory : System.MarshalByRefObject,IDisposable { …/// <summary> /// TypeParser Factory method that loads the TypeParser /// object into a new AppDomain so it can be unloaded. /// Creates AppDomain and creates type. /// </summary> /// <returns></returns> public TypeParser CreateTypeParser() { if (!CreateAppDomain(null)) return null; /// Create the instance inside of the new AppDomain /// Note: remote domain uses local EXE's AppBasePath!!! TypeParser parser = null; try { Assembly assembly = Assembly.GetExecutingAssembly(); string assemblyPath = Assembly.GetExecutingAssembly().Location; parser = (TypeParser) this.LocalAppDomain.CreateInstanceFrom(assemblyPath, typeof(TypeParser).FullName).Unwrap(); } catch (Exception ex) { this.ErrorMessage = ex.GetBaseException().Message; return null; } return parser; } private bool CreateAppDomain(string lcAppDomain) { if (lcAppDomain == null) lcAppDomain = "wwReflection" + Guid.NewGuid().ToString().GetHashCode().ToString("x"); AppDomainSetup setup = new AppDomainSetup(); // *** Point at current directory setup.ApplicationBase = AppDomain.CurrentDomain.BaseDirectory; //setup.PrivateBinPath = Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "bin"); this.LocalAppDomain = AppDomain.CreateDomain(lcAppDomain,null,setup); // Need a custom resolver so we can load assembly from non current path AppDomain.CurrentDomain.AssemblyResolve += new ResolveEventHandler(CurrentDomain_AssemblyResolve); return true; } …} Note that the classes must be either [Serializable] (by value) or inherit from MarshalByRefObject in order to be accessible remotely. Here I need to call methods on the remote object so all classes are MarshalByRefObject. The specific problem code is the loading up a new type which points at an assembly that visible both in the current domain and the remote domain and then instantiates a type from it. This is the code in question:Assembly assembly = Assembly.GetExecutingAssembly(); string assemblyPath = Assembly.GetExecutingAssembly().Location; parser = (TypeParser) this.LocalAppDomain.CreateInstanceFrom(assemblyPath, typeof(TypeParser).FullName).Unwrap(); The last line of code is what blows up with the Unable to cast transparent proxy to type <type> error. Without the cast the code actually returns a TransparentProxy instance, but the cast is what blows up. In other words I AM in fact getting a TypeParser instance back but it can't be cast to the TypeParser type that is loaded in the current AppDomain. Finding the Problem To see what's going on I tried using the .NET 4.0 dynamic type on the result and lo and behold it worked with dynamic - the value returned is actually a TypeParser instance: Assembly assembly = Assembly.GetExecutingAssembly(); string assemblyPath = Assembly.GetExecutingAssembly().Location; object objparser = this.LocalAppDomain.CreateInstanceFrom(assemblyPath, typeof(TypeParser).FullName).Unwrap(); // dynamic works dynamic dynParser = objparser; string info = dynParser.GetVersionInfo(); // method call works // casting fails parser = (TypeParser)objparser; So clearly a TypeParser type is coming back, but nevertheless it's not the right one. Hmmm… mysterious.Another couple of tries reveal the problem however:// works dynamic dynParser = objparser; string info = dynParser.GetVersionInfo(); // method call works // c:\wwapps\wwhelp\wwReflection20.dll (Current Execution Folder) string info3 = typeof(TypeParser).Assembly.CodeBase; // c:\program files\vfp9\wwReflection20.dll (my COM client EXE's folder) string info4 = dynParser.GetType().Assembly.CodeBase; // fails parser = (TypeParser)objparser; As you can see the second value is coming from a totally different assembly. Note that this is even though I EXPLICITLY SPECIFIED an assembly path to load the assembly from! Instead .NET decided to load the assembly from the original ApplicationBase folder. Ouch! How I actually tracked this down was a little more tedious: I added a method like this to both the factory and the instance types and then compared notes:public string GetVersionInfo() { return ".NET Version: " + Environment.Version.ToString() + "\r\n" + "wwReflection Assembly: " + typeof(TypeParserFactory).Assembly.CodeBase.Replace("file:///", "").Replace("/", "\\") + "\r\n" + "Assembly Cur Dir: " + Directory.GetCurrentDirectory() + "\r\n" + "ApplicationBase: " + AppDomain.CurrentDomain.SetupInformation.ApplicationBase + "\r\n" + "App Domain: " + AppDomain.CurrentDomain.FriendlyName + "\r\n"; } For the factory I got: .NET Version: 4.0.30319.239wwReflection Assembly: c:\wwapps\wwhelp\bin\wwreflection20.dllAssembly Cur Dir: c:\wwapps\wwhelpApplicationBase: C:\Programs\vfp9\App Domain: wwReflection534cfa1f For the instance type I got: .NET Version: 4.0.30319.239wwReflection Assembly: C:\\Programs\\vfp9\wwreflection20.dllAssembly Cur Dir: c:\\wwapps\\wwhelpApplicationBase: C:\\Programs\\vfp9\App Domain: wwDotNetBridge_56006605 which clearly shows the problem. You can see that both are loading from different appDomains but the each is loading the assembly from a different location. Probably a better solution yet (for ANY kind of assembly loading problem) is to use the .NET Fusion Log Viewer to trace assembly loads.The Fusion viewer will show a load trace for each assembly loaded and where it's looking to find it. Here's what the viewer looks like: The last trace above that I found for the second wwReflection20 load (the one that is wonky) looks like this:*** Assembly Binder Log Entry (1/13/2012 @ 3:06:49 AM) *** The operation was successful. Bind result: hr = 0x0. The operation completed successfully. Assembly manager loaded from: C:\Windows\Microsoft.NET\Framework\V4.0.30319\clr.dll Running under executable c:\programs\vfp9\vfp9.exe --- A detailed error log follows. === Pre-bind state information === LOG: User = Ras\ricks LOG: DisplayName = wwReflection20, Version=4.61.0.0, Culture=neutral, PublicKeyToken=null (Fully-specified) LOG: Appbase = file:///C:/Programs/vfp9/ LOG: Initial PrivatePath = NULL LOG: Dynamic Base = NULL LOG: Cache Base = NULL LOG: AppName = vfp9.exe Calling assembly : (Unknown). === LOG: This bind starts in default load context. LOG: Using application configuration file: C:\Programs\vfp9\vfp9.exe.Config LOG: Using host configuration file: LOG: Using machine configuration file from C:\Windows\Microsoft.NET\Framework\V4.0.30319\config\machine.config. LOG: Policy not being applied to reference at this time (private, custom, partial, or location-based assembly bind). LOG: Attempting download of new URL file:///C:/Programs/vfp9/wwReflection20.DLL. LOG: Assembly download was successful. Attempting setup of file: C:\Programs\vfp9\wwReflection20.dll LOG: Entering run-from-source setup phase. LOG: Assembly Name is: wwReflection20, Version=4.61.0.0, Culture=neutral, PublicKeyToken=null LOG: Binding succeeds. Returns assembly from C:\Programs\vfp9\wwReflection20.dll. LOG: Assembly is loaded in default load context. WRN: The same assembly was loaded into multiple contexts of an application domain: WRN: Context: Default | Domain ID: 2 | Assembly Name: wwReflection20, Version=4.61.0.0, Culture=neutral, PublicKeyToken=null WRN: Context: LoadFrom | Domain ID: 2 | Assembly Name: wwReflection20, Version=4.61.0.0, Culture=neutral, PublicKeyToken=null WRN: This might lead to runtime failures. WRN: It is recommended to inspect your application on whether this is intentional or not. WRN: See whitepaper http://go.microsoft.com/fwlink/?LinkId=109270 for more information and common solutions to this issue. Notice that the fusion log clearly shows that the .NET loader makes no attempt to even load the assembly from the path I explicitly specified. Remember your Assembly Locations As mentioned earlier all failures I've seen like this ultimately resulted from different versions of the same type being available in the two AppDomains. At first sight that seems ridiculous - how could the types be different and why would you have multiple assemblies - but there are actually a number of scenarios where it's quite possible to have multiple copies of the same assembly floating around in multiple places. If you're hosting different environments (like hosting the Razor Engine, or ASP.NET Runtime for example) it's common to create a private BIN folder and it's important to make sure that there's no overlap of assemblies. In my case of Html Help Builder the problem started because I'm using COM interop to access the .NET assembly and the above code. COM Interop has very specific requirements on where assemblies can be found and because I was mucking around with the loader code today, I ended up moving assemblies around to a new location for explicit loading. The explicit load works in the main AppDomain, but failed in the remote domain as I showed. The solution here was simple enough: Delete the extraneous assembly which was left around by accident. Not a common problem, but one that when it bites is pretty nasty to figure out because it seems so unlikely that types wouldn't match. I know I've run into this a few times and writing this down hopefully will make me remember in the future rather than poking around again for an hour trying to debug the issue as I did today. Hopefully it'll save some of you some time as well in the future.© Rick Strahl, West Wind Technologies, 2005-2012Posted in .NET  COM   Tweet !function(d,s,id){var js,fjs=d.getElementsByTagName(s)[0];if(!d.getElementById(id)){js=d.createElement(s);js.id=id;js.src="//platform.twitter.com/widgets.js";fjs.parentNode.insertBefore(js,fjs);}}(document,"script","twitter-wjs"); (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

  Read the article

• Right-Time Retail Part 3

  - by David Dorf

  This is part three of the three-part series.  Read Part 1 and Part 2 first. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Right-Time Marketing Real-time isn’t just about executing faster; it extends to interactions with customers as well. As an industry, we’ve spent many years analyzing all the data that’s been collected. Yes, that data has been invaluable in helping us make better decisions like where to open new stores, how to assort those stores, and how to price our products. But the recent advances in technology are now making it possible to analyze and deliver that data very quickly… fast enough to impact a potential sale in near real-time. Let me give you two examples. Salesmen in car dealerships get pretty good at sizing people up. When a potential customer walks in the door, it doesn’t take long for the salesman to figure out the revenue at stake. Is this person a real buyer, or just looking for a fun test drive? Will this person buy today or three months from now? Will this person opt for the expensive packages, or go bare bones? While the salesman certainly asks some leading questions, much of information is discerned through body language. But body language doesn’t translate very well over the web. Eloqua, which was acquired by Oracle earlier this year, reads internet body language. By tracking the behavior of the people visiting your web site, Eloqua categorizes visitors based on their propensity to buy. While Eloqua’s roots have been in B2B, we’ve been looking at leveraging the technology with ATG to target B2C. Knowing what sites were previously visited, how often the customer has been to your site recently, and how long they’ve spent searching can help understand where the customer is in their purchase journey. And knowing that bit of information may be enough to help close the deal with a real-time offer, follow-up email, or online customer service pop-up. This isn’t so different from the days gone by when the clerk behind the counter of the corner store noticed you were lingering in a particular aisle, so he walked over to help you compare two products and close the sale. You appreciated the personalized service, and he knew the value of the long-term relationship. Move that same concept into the digital world and you have Oracle’s CX Suite, a cloud-based offering of end-to-end customer experience tools, assembled primarily from acquisitions. Those tools are Oracle Marketing (Eloqua), Oracle Commerce (ATG, Endeca), Oracle Sales (Oracle CRM On Demand), Oracle Service (RightNow), Oracle Social (Collective Intellect, Vitrue, Involver), and Oracle Content (Fatwire). We are providing the glue that binds the CIO and CMO together to unleash synergies that drive the top-line higher, and by virtue of the cloud-approach, keep costs at bay. My second example of real-time marketing takes place in the store but leverages the concepts of Web marketing. In 1962 the decline of personalized service in retail began. Anyone know the significance of that year? That’s when Target, K-Mart, and Walmart each opened their first stores, and over the succeeding years the industry chose scale over personal service. No longer were you known as “Jane with the snotty kid so make sure we check her out fast,” but you suddenly became “time-starved female age 20-30 with kids.” I’m not saying that was a bad thing – it was the right thing for our industry at the time, and it enabled a huge amount of growth, cheaper prices, and more variety of products. But scale alone is no longer good enough. Today’s sophisticated consumer demands scale, experience, and personal attention. To some extent we’ve delivered that on websites via the magic of cookies, your willingness to log in, and sophisticated data analytics. What store manager wouldn’t love a report detailing all the visitors to his store, where they came from, and which products that examined? People trackers are getting more sophisticated, incorporating infrared, video analytics, and even face recognition. (Next time you walk in front on a mannequin, don’t be surprised if it’s looking back.) But the ultimate marketing conduit is the mobile phone. Since each mobile phone emits a unique number on WiFi networks, it becomes the cookie of the physical world. Assuming congress keeps privacy safeguards reasonable, we’ll have a win-win situation for both retailers and consumers. Retailers get to know more about the consumer’s purchase journey, and consumers get higher levels of service with the retailer. When I call my bank, a couple things happen before the call is connected. A reverse look-up on my phone number identifies me so my accounts can be retrieved from Siebel CRM. Then the system anticipates why I’m calling based on recent transactions. In this example, it sees that I was just charged a foreign currency fee, so it assumes that’s the reason I’m calling. It puts all the relevant information on the customer service rep’s screen as it connects the call. When I complain about the fee, the rep immediately sees I’m a great customer and I travel lots, so she suggests switching me to their traveler’s card that doesn’t have foreign transaction fees. That technology is powered by a product called Oracle Real-Time Decisions, a rules engine built to execute very quickly, basically in the time it takes the phone to ring once. So let’s combine the power of that product with our new-found mobile cookie and provide contextual customer interactions in real-time. Our first opportunity comes when a customer crosses a pre-defined geo-fence, typically a boundary around the store. Context is the key to our interaction: that’s the customer (known or anonymous), the time of day and day of week, and location. Thomas near the downtown store on a Wednesday at noon means he’s heading to lunch. If he were near the mall location on a Saturday morning, that’s a completely different context. But on his way to lunch, we’ll let Thomas know that we’ve got a new shipment of ASICS running shoes on display with a simple text message. We used the context to look-up Thomas’ past purchases and understood he was an avid runner. We used the fact that this was lunchtime to select the type of message, in this case an informational message instead of an offer. Thomas enters the store, phone in hand, and walks to the shoe department. He scans one of the new ASICS shoes using the convenient QR Codes we provided on the shelf-tags, but then he starts scanning low-end Nikes. Each scan is another opportunity to both learn from Thomas and potentially interact via another message. Since he historically buys low-end Nikes and keeps scanning them, he’s likely falling back into his old ways. Our marketing rules are currently set to move loyal customer to higher margin products. We could have set the dials to increase visit frequency, move overstocked items, increase basket size, or many other settings, but today we are trying to move Thomas to higher-margin products. We send Thomas another text message, this time it’s a personalized offer for 10% off ASICS good for 24 hours. Offering him a discount on Nikes would be throwing margin away since he buys those anyway. We are using our marketing dollars to change behavior that increases the long-term value of Thomas. He decides to buy the ASICS and scans the discount code on his phone at checkout. Checkout is yet another opportunity to interact with Thomas, so the transaction is sent back to Oracle RTD for evaluation. Since Thomas didn’t buy anything with the shoes, we’ll print a bounce-back coupon on the receipt offering 30% off ASICS socks if he returns within seven days. We have successfully started moving Thomas from low-margin to high-margin products. In both of these marketing scenarios, we are able to leverage data in near real-time to decide how best to interact with the customer and lead to an increase in the lifetime value of the customer. The key here is acting at the moment the customer shows interest using the context of the situation. We aren’t pushing random products at haphazard times. We are tailoring the marketing to be very specific to this customer, and it’s the technology that allows this to happen in near real-time. Conclusion As we enable more right-time integrations and interactions, retailers will begin to offer increased service to their customers. Localized and personalized service at scale will drive loyalty and lead to meaningful revenue growth for the retailers that execute well. Our industry needs to support Commerce Anywhere…and commerce anytime as well.

  Read the article

• WSDL-world vs CLR-world – some differences

  - by nmarun

  A change in mindset is required when switching between a typical CLR application and a web service application. There are some things in a CLR environment that just don’t add-up in a WSDL arena (and vice-versa). I’m listing some of them here. When I say WSDL-world, I’m mostly talking with respect to a WCF Service and / or a Web Service. No (direct) Method Overloading: You definitely can have overloaded methods in a, say, Console application, but when it comes to a WCF / Web Services application, you need to adorn these overloaded methods with a special attribute so the service knows which specific method to invoke. When you’re working with WCF, use the Name property of the OperationContract attribute to provide unique names. 1: [OperationContract(Name = "AddInt")] 2: int Add(int arg1, int arg2); 3:  4: [OperationContract(Name = "AddDouble")] 5: double Add(double arg1, double arg2); By default, the proxy generates the code for this as: 1: [System.ServiceModel.OperationContractAttribute( 2: Action="http://tempuri.org/ILearnWcfService/AddInt", 3: ReplyAction="http://tempuri.org/ILearnWcfService/AddIntResponse")] 4: int AddInt(int arg1, int arg2); 5: 6: [System.ServiceModel.OperationContractAttribute( 7: Action="http://tempuri.org/ILearnWcfServiceExtend/AddDouble", 8: ReplyAction="http://tempuri.org/ILearnWcfServiceExtend/AddDoubleResponse")] 9: double AddDouble(double arg1, double arg2); With Web Services though the story is slightly different. Even after setting the MessageName property of the WebMethod attribute, the proxy does not change the name of the method, but only the underlying soap message changes. 1: [WebMethod] 2: public string HelloGalaxy() 3: { 4: return "Hello Milky Way!"; 5: } 6:  7: [WebMethod(MessageName = "HelloAnyGalaxy")] 8: public string HelloGalaxy(string galaxyName) 9: { 10: return string.Format("Hello {0}!", galaxyName); 11: } The one thing you need to remember is to set the WebServiceBinding accordingly. 1: [WebServiceBinding(ConformsTo = WsiProfiles.None)] The proxy is: 1: [System.Web.Services.Protocols.SoapDocumentMethodAttribute("http://tempuri.org/HelloGalaxy", 2: RequestNamespace="http://tempuri.org/", 3: ResponseNamespace="http://tempuri.org/", 4: Use=System.Web.Services.Description.SoapBindingUse.Literal, 5: ParameterStyle=System.Web.Services.Protocols.SoapParameterStyle.Wrapped)] 6: public string HelloGalaxy() 7:  8: [System.Web.Services.WebMethodAttribute(MessageName="HelloGalaxy1")] 9: [System.Web.Services.Protocols.SoapDocumentMethodAttribute("http://tempuri.org/HelloAnyGalaxy", 10: RequestElementName="HelloAnyGalaxy", 11: RequestNamespace="http://tempuri.org/", 12: ResponseElementName="HelloAnyGalaxyResponse", 13: ResponseNamespace="http://tempuri.org/", 14: Use=System.Web.Services.Description.SoapBindingUse.Literal, 15: ParameterStyle=System.Web.Services.Protocols.SoapParameterStyle.Wrapped)] 16: [return: System.Xml.Serialization.XmlElementAttribute("HelloAnyGalaxyResult")] 17: public string HelloGalaxy(string galaxyName) 18:  You see the calling method name is the same in the proxy, however the soap message that gets generated is different. Using interchangeable data types: See details on this here. Type visibility: In a CLR-based application, if you mark a field as private, well we all know, it’s ‘private’. Coming to a WSDL side of things, in a Web Service, private fields and web methods will not get generated in the proxy. In WCF however, all your operation contracts will be public as they get implemented from an interface. Even in case your ServiceContract interface is declared internal/private, you will see it as a public interface in the proxy. This is because type visibility is a CLR concept and has no bearing on WCF. Also if a private field has the [DataMember] attribute in a data contract, it will get emitted in the proxy class as a public property for the very same reason. 1: [DataContract] 2: public struct Person 3: { 4: [DataMember] 5: private int _x; 6:  7: [DataMember] 8: public int Id { get; set; } 9:  10: [DataMember] 11: public string FirstName { get; set; } 12:  13: [DataMember] 14: public string Header { get; set; } 15: } 16: } See the ‘_x’ field is a private member with the [DataMember] attribute, but the proxy class shows as below: 1: [System.Runtime.Serialization.DataMemberAttribute()] 2: public int _x { 3: get { 4: return this._xField; 5: } 6: set { 7: if ((this._xField.Equals(value) != true)) { 8: this._xField = value; 9: this.RaisePropertyChanged("_x"); 10: } 11: } 12: } Passing derived types to web methods / operation contracts: Once again, in a CLR application, I can have a derived class be passed as a parameter where a base class is expected. I have the following set up for my WCF service. 1: [DataContract] 2: public class Employee 3: { 4: [DataMember(Name = "Id")] 5: public int EmployeeId { get; set; } 6:  7: [DataMember(Name="FirstName")] 8: public string FName { get; set; } 9:  10: [DataMember] 11: public string Header { get; set; } 12: } 13:  14: [DataContract] 15: public class Manager : Employee 16: { 17: [DataMember] 18: private int _x; 19: } 20:  21: // service contract 22: [OperationContract] 23: Manager SaveManager(Employee employee); 24:  25: // in my calling code 26: Manager manager = new Manager {_x = 1, FirstName = "abc"}; 27: manager = LearnWcfServiceClient.SaveManager(manager); The above will throw an exception saying: In short, this is saying, that a Manager type was found where an Employee type was expected! Hierarchy flattening of interfaces in WCF: See details on this here. In CLR world, you’ll see the entire hierarchy as is. That’s another difference. Using ref parameters: * can use ref for parameters, but operation contract should not be one-way (gives an error when you do an update service reference)   => bad programming; create a return object that is composed of everything you need! This one kind of stumped me. Not sure why I tried this, but you can pass parameters prefixed with ref keyword* (* terms and conditions apply). The main issue is this, how would we know the changes that were made to a ‘ref’ input parameter are returned back from the service and updated to the local variable? Turns out both Web Services and WCF make this tracking happen by passing the input parameter in the response soap. This way when the deserializer does its magic, it maps all the elements of the response xml thereby updating our local variable. Here’s what I’m talking about. 1: [WebMethod(MessageName = "HelloAnyGalaxy")] 2: public string HelloGalaxy(ref string galaxyName) 3: { 4: string output = string.Format("Hello {0}", galaxyName); 5: if (galaxyName == "Andromeda") 6: { 7: galaxyName = string.Format("{0} (2.5 million light-years away)", galaxyName); 8: } 9: return output; 10: } This is how the request and response look like in soapUI. As I said above, the behavior is quite similar for WCF as well. But the catch comes when you have a one-way web methods / operation contracts. If you have an operation contract whose return type is void, is marked one-way and that has ref parameters then you’ll get an error message when you try to reference such a service. 1: [OperationContract(Name = "Sum", IsOneWay = true)] 2: void Sum(ref double arg1, ref double arg2); 3:  4: public void Sum(ref double arg1, ref double arg2) 5: { 6: arg1 += arg2; 7: } This is what I got when I did an update to my service reference: Makes sense, because a OneWay operation is… one-way – there’s no returning from this operation. You can also have a one-way web method: 1: [SoapDocumentMethod(OneWay = true)] 2: [WebMethod(MessageName = "HelloAnyGalaxy")] 3: public void HelloGalaxy(ref string galaxyName) This will throw an exception message similar to the one above when you try to update your web service reference. In the CLR space, there’s no such concept of a ‘one-way’ street! Yes, there’s void, but you very well can have ref parameters returned through such a method. Just a point here; although the ref/out concept sounds cool, it’s generally is a code-smell. The better approach is to always return an object that is composed of everything you need returned from a method. These are some of the differences that we need to bear when dealing with services that are different from our daily ‘CLR’ life.

  Read the article

• Juju Openstack bundle: Can't launch an instance

  - by user281985

  Deployed bundle:~makyo/openstack/2/openstack, on top of 7 physical boxes and 3 virtual ones. After changing vip_iface strings to point to right devices, e.g., br0 instead of eth0, and defining "/mnt/loopback|30G", in Cinder's block-device string, am able to navigate through openstack dashboard, error free. Following http://docs.openstack.org/grizzly/openstack-compute/install/apt/content/running-an-instance.html instructions, attempted to launch cirros 0.3.1 image; however, novalist shows the instance in error state. ubuntu@node7:~$ nova --debug boot --flavor 1 --image 28bed1bc-bc1c-4533-beee-8e0428ad40dd --key_name key2 --security_group default cirros REQ: curl -i http://keyStone.IP:5000/v2.0/tokens -X POST -H "Content-Type: application/json" -H "Accept: application/json" -H "User-Agent: python-novaclient" -d '{"auth": {"tenantName": "admin", "passwordCredentials": {"username": "admin", "password": "openstack"}}}' INFO (connectionpool:191) Starting new HTTP connection (1): keyStone.IP DEBUG (connectionpool:283) "POST /v2.0/tokens HTTP/1.1" 200 None RESP: [200] {'date': 'Tue, 10 Jun 2014 00:01:02 GMT', 'transfer-encoding': 'chunked', 'vary': 'X-Auth-Token', 'content-type': 'application/json'} RESP BODY: {"access": {"token": {"expires": "2014-06-11T00:01:02Z", "id": "3eefa1837d984426a633fe09259a1534", "tenant": {"description": "Created by Juju", "enabled": true, "id": "08cff06d13b74492b780d9ceed699239", "name": "admin"}}, "serviceCatalog": [{"endpoints": [{"adminURL": "http://nova.cloud.controller:8774/v1.1/08cff06d13b74492b780d9ceed699239", "region": "RegionOne", "internalURL": "http://nova.cloud.controller:8774/v1.1/08cff06d13b74492b780d9ceed699239", "publicURL": "http://nova.cloud.controller:8774/v1.1/08cff06d13b74492b780d9ceed699239"}], "endpoints_links": [], "type": "compute", "name": "nova"}, {"endpoints": [{"adminURL": "http://nova.cloud.controller:9696", "region": "RegionOne", "internalURL": "http://nova.cloud.controller:9696", "publicURL": "http://nova.cloud.controller:9696"}], "endpoints_links": [], "type": "network", "name": "quantum"}, {"endpoints": [{"adminURL": "http://nova.cloud.controller:3333", "region": "RegionOne", "internalURL": "http://nova.cloud.controller:3333", "publicURL": "http://nova.cloud.controller:3333"}], "endpoints_links": [], "type": "s3", "name": "s3"}, {"endpoints": [{"adminURL": "http://i.p.s.36:9292", "region": "RegionOne", "internalURL": "http://i.p.s.36:9292", "publicURL": "http://i.p.s.36:9292"}], "endpoints_links": [], "type": "image", "name": "glance"}, {"endpoints": [{"adminURL": "http://i.p.s.39:8776/v1/08cff06d13b74492b780d9ceed699239", "region": "RegionOne", "internalURL": "http://i.p.s.39:8776/v1/08cff06d13b74492b780d9ceed699239", "publicURL": "http://i.p.s.39:8776/v1/08cff06d13b74492b780d9ceed699239"}], "endpoints_links": [], "type": "volume", "name": "cinder"}, {"endpoints": [{"adminURL": "http://nova.cloud.controller:8773/services/Cloud", "region": "RegionOne", "internalURL": "http://nova.cloud.controller:8773/services/Cloud", "publicURL": "http://nova.cloud.controller:8773/services/Cloud"}], "endpoints_links": [], "type": "ec2", "name": "ec2"}, {"endpoints": [{"adminURL": "http://keyStone.IP:35357/v2.0", "region": "RegionOne", "internalURL": "http://keyStone.IP:5000/v2.0", "publicURL": "http://i.p.s.44:5000/v2.0"}], "endpoints_links": [], "type": "identity", "name": "keystone"}], "user": {"username": "admin", "roles_links": [], "id": "b3730a52a32e40f0a9500440d1ef1c7d", "roles": [{"id": "e020001eb9a049f4a16540238ab158aa", "name": "Admin"}, {"id": "b84fbff4d5554d53bbbffdaad66b56cb", "name": "KeystoneServiceAdmin"}, {"id": "129c8b49d42b4f0796109aaef2069aa9", "name": "KeystoneAdmin"}], "name": "admin"}}} REQ: curl -i http://nova.cloud.controller:8774/v1.1/08cff06d13b74492b780d9ceed699239/images/28bed1bc-bc1c-4533-beee-8e0428ad40dd -X GET -H "X-Auth-Project-Id: admin" -H "User-Agent: python-novaclient" -H "Accept: application/json" -H "X-Auth-Token: 3eefa1837d984426a633fe09259a1534" INFO (connectionpool:191) Starting new HTTP connection (1): nova.cloud.controller DEBUG (connectionpool:283) "GET /v1.1/08cff06d13b74492b780d9ceed699239/images/28bed1bc-bc1c-4533-beee-8e0428ad40dd HTTP/1.1" 200 719 RESP: [200] {'date': 'Tue, 10 Jun 2014 00:01:03 GMT', 'x-compute-request-id': 'req-7f3459f8-d3d5-47f1-97a3-8407a4419a69', 'content-type': 'application/json', 'content-length': '719'} RESP BODY: {"image": {"status": "ACTIVE", "updated": "2014-06-09T22:17:54Z", "links": [{"href": "http://nova.cloud.controller:8774/v1.1/08cff06d13b74492b780d9ceed699239/images/28bed1bc-bc1c-4533-beee-8e0428ad40dd", "rel": "self"}, {"href": "http://nova.cloud.controller:8774/08cff06d13b74492b780d9ceed699239/images/28bed1bc-bc1c-4533-beee-8e0428ad40dd", "rel": "bookmark"}, {"href": "http://External.Public.Port:9292/08cff06d13b74492b780d9ceed699239/images/28bed1bc-bc1c-4533-beee-8e0428ad40dd", "type": "application/vnd.openstack.image", "rel": "alternate"}], "id": "28bed1bc-bc1c-4533-beee-8e0428ad40dd", "OS-EXT-IMG-SIZE:size": 13147648, "name": "Cirros 0.3.1", "created": "2014-06-09T22:17:54Z", "minDisk": 0, "progress": 100, "minRam": 0, "metadata": {}}} REQ: curl -i http://nova.cloud.controller:8774/v1.1/08cff06d13b74492b780d9ceed699239/flavors/1 -X GET -H "X-Auth-Project-Id: admin" -H "User-Agent: python-novaclient" -H "Accept: application/json" -H "X-Auth-Token: 3eefa1837d984426a633fe09259a1534" INFO (connectionpool:191) Starting new HTTP connection (1): nova.cloud.controller DEBUG (connectionpool:283) "GET /v1.1/08cff06d13b74492b780d9ceed699239/flavors/1 HTTP/1.1" 200 418 RESP: [200] {'date': 'Tue, 10 Jun 2014 00:01:04 GMT', 'x-compute-request-id': 'req-2c153110-6969-4f3a-b51c-8f1a6ce75bee', 'content-type': 'application/json', 'content-length': '418'} RESP BODY: {"flavor": {"name": "m1.tiny", "links": [{"href": "http://nova.cloud.controller:8774/v1.1/08cff06d13b74492b780d9ceed699239/flavors/1", "rel": "self"}, {"href": "http://nova.cloud.controller:8774/08cff06d13b74492b780d9ceed699239/flavors/1", "rel": "bookmark"}], "ram": 512, "OS-FLV-DISABLED:disabled": false, "vcpus": 1, "swap": "", "os-flavor-access:is_public": true, "rxtx_factor": 1.0, "OS-FLV-EXT-DATA:ephemeral": 0, "disk": 0, "id": "1"}} REQ: curl -i http://nova.cloud.controller:8774/v1.1/08cff06d13b74492b780d9ceed699239/servers -X POST -H "X-Auth-Project-Id: admin" -H "User-Agent: python-novaclient" -H "Content-Type: application/json" -H "Accept: application/json" -H "X-Auth-Token: 3eefa1837d984426a633fe09259a1534" -d '{"server": {"name": "cirros", "imageRef": "28bed1bc-bc1c-4533-beee-8e0428ad40dd", "key_name": "key2", "flavorRef": "1", "max_count": 1, "min_count": 1, "security_groups": [{"name": "default"}]}}' INFO (connectionpool:191) Starting new HTTP connection (1): nova.cloud.controller DEBUG (connectionpool:283) "POST /v1.1/08cff06d13b74492b780d9ceed699239/servers HTTP/1.1" 202 436 RESP: [202] {'date': 'Tue, 10 Jun 2014 00:01:05 GMT', 'x-compute-request-id': 'req-41e53086-6454-4efb-bb35-a30dc2c780be', 'content-type': 'application/json', 'location': 'http://nova.cloud.controller:8774/v1.1/08cff06d13b74492b780d9ceed699239/servers/2eb5e3ad-3044-41c1-bbb7-10f398f83e43', 'content-length': '436'} RESP BODY: {"server": {"security_groups": [{"name": "default"}], "OS-DCF:diskConfig": "MANUAL", "id": "2eb5e3ad-3044-41c1-bbb7-10f398f83e43", "links": [{"href": "http://nova.cloud.controller:8774/v1.1/08cff06d13b74492b780d9ceed699239/servers/2eb5e3ad-3044-41c1-bbb7-10f398f83e43", "rel": "self"}, {"href": "http://nova.cloud.controller:8774/08cff06d13b74492b780d9ceed699239/servers/2eb5e3ad-3044-41c1-bbb7-10f398f83e43", "rel": "bookmark"}], "adminPass": "oFRbvRqif2C8"}} REQ: curl -i http://nova.cloud.controller:8774/v1.1/08cff06d13b74492b780d9ceed699239/servers/2eb5e3ad-3044-41c1-bbb7-10f398f83e43 -X GET -H "X-Auth-Project-Id: admin" -H "User-Agent: python-novaclient" -H "Accept: application/json" -H "X-Auth-Token: 3eefa1837d984426a633fe09259a1534" INFO (connectionpool:191) Starting new HTTP connection (1): nova.cloud.controller DEBUG (connectionpool:283) "GET /v1.1/08cff06d13b74492b780d9ceed699239/servers/2eb5e3ad-3044-41c1-bbb7-10f398f83e43 HTTP/1.1" 200 1349 RESP: [200] {'date': 'Tue, 10 Jun 2014 00:01:05 GMT', 'x-compute-request-id': 'req-d91d0858-7030-469d-8e55-40e05e4d00fd', 'content-type': 'application/json', 'content-length': '1349'} RESP BODY: {"server": {"status": "BUILD", "updated": "2014-06-10T00:01:05Z", "hostId": "", "OS-EXT-SRV-ATTR:host": null, "addresses": {}, "links": [{"href": "http://nova.cloud.controller:8774/v1.1/08cff06d13b74492b780d9ceed699239/servers/2eb5e3ad-3044-41c1-bbb7-10f398f83e43", "rel": "self"}, {"href": "http://nova.cloud.controller:8774/08cff06d13b74492b780d9ceed699239/servers/2eb5e3ad-3044-41c1-bbb7-10f398f83e43", "rel": "bookmark"}], "key_name": "key2", "image": {"id": "28bed1bc-bc1c-4533-beee-8e0428ad40dd", "links": [{"href": "http://nova.cloud.controller:8774/08cff06d13b74492b780d9ceed699239/images/28bed1bc-bc1c-4533-beee-8e0428ad40dd", "rel": "bookmark"}]}, "OS-EXT-STS:task_state": "scheduling", "OS-EXT-STS:vm_state": "building", "OS-EXT-SRV-ATTR:instance_name": "instance-00000004", "OS-EXT-SRV-ATTR:hypervisor_hostname": null, "flavor": {"id": "1", "links": [{"href": "http://nova.cloud.controller:8774/08cff06d13b74492b780d9ceed699239/flavors/1", "rel": "bookmark"}]}, "id": "2eb5e3ad-3044-41c1-bbb7-10f398f83e43", "security_groups": [{"name": "default"}], "OS-EXT-AZ:availability_zone": "nova", "user_id": "b3730a52a32e40f0a9500440d1ef1c7d", "name": "cirros", "created": "2014-06-10T00:01:04Z", "tenant_id": "08cff06d13b74492b780d9ceed699239", "OS-DCF:diskConfig": "MANUAL", "accessIPv4": "", "accessIPv6": "", "progress": 0, "OS-EXT-STS:power_state": 0, "config_drive": "", "metadata": {}}} REQ: curl -i http://nova.cloud.controller:8774/v1.1/08cff06d13b74492b780d9ceed699239/flavors/1 -X GET -H "X-Auth-Project-Id: admin" -H "User-Agent: python-novaclient" -H "Accept: application/json" -H "X-Auth-Token: 3eefa1837d984426a633fe09259a1534" INFO (connectionpool:191) Starting new HTTP connection (1): nova.cloud.controller DEBUG (connectionpool:283) "GET /v1.1/08cff06d13b74492b780d9ceed699239/flavors/1 HTTP/1.1" 200 418 RESP: [200] {'date': 'Tue, 10 Jun 2014 00:01:05 GMT', 'x-compute-request-id': 'req-896c0120-1102-4408-9e09-cd628f2dd699', 'content-type': 'application/json', 'content-length': '418'} RESP BODY: {"flavor": {"name": "m1.tiny", "links": [{"href": "http://nova.cloud.controller:8774/v1.1/08cff06d13b74492b780d9ceed699239/flavors/1", "rel": "self"}, {"href": "http://nova.cloud.controller:8774/08cff06d13b74492b780d9ceed699239/flavors/1", "rel": "bookmark"}], "ram": 512, "OS-FLV-DISABLED:disabled": false, "vcpus": 1, "swap": "", "os-flavor-access:is_public": true, "rxtx_factor": 1.0, "OS-FLV-EXT-DATA:ephemeral": 0, "disk": 0, "id": "1"}} REQ: curl -i http://nova.cloud.controller:8774/v1.1/08cff06d13b74492b780d9ceed699239/images/28bed1bc-bc1c-4533-beee-8e0428ad40dd -X GET -H "X-Auth-Project-Id: admin" -H "User-Agent: python-novaclient" -H "Accept: application/json" -H "X-Auth-Token: 3eefa1837d984426a633fe09259a1534" INFO (connectionpool:191) Starting new HTTP connection (1): nova.cloud.controller DEBUG (connectionpool:283) "GET /v1.1/08cff06d13b74492b780d9ceed699239/images/28bed1bc-bc1c-4533-beee-8e0428ad40dd HTTP/1.1" 200 719 RESP: [200] {'date': 'Tue, 10 Jun 2014 00:01:05 GMT', 'x-compute-request-id': 'req-454e9651-c247-4d31-8049-6b254de050ae', 'content-type': 'application/json', 'content-length': '719'} RESP BODY: {"image": {"status": "ACTIVE", "updated": "2014-06-09T22:17:54Z", "links": [{"href": "http://nova.cloud.controller:8774/v1.1/08cff06d13b74492b780d9ceed699239/images/28bed1bc-bc1c-4533-beee-8e0428ad40dd", "rel": "self"}, {"href": "http://nova.cloud.controller:8774/08cff06d13b74492b780d9ceed699239/images/28bed1bc-bc1c-4533-beee-8e0428ad40dd", "rel": "bookmark"}, {"href": "http://External.Public.Port:9292/08cff06d13b74492b780d9ceed699239/images/28bed1bc-bc1c-4533-beee-8e0428ad40dd", "type": "application/vnd.openstack.image", "rel": "alternate"}], "id": "28bed1bc-bc1c-4533-beee-8e0428ad40dd", "OS-EXT-IMG-SIZE:size": 13147648, "name": "Cirros 0.3.1", "created": "2014-06-09T22:17:54Z", "minDisk": 0, "progress": 100, "minRam": 0, "metadata": {}}} +-------------------------------------+--------------------------------------+ | Property | Value | +-------------------------------------+--------------------------------------+ | OS-EXT-STS:task_state | scheduling | | image | Cirros 0.3.1 | | OS-EXT-STS:vm_state | building | | OS-EXT-SRV-ATTR:instance_name | instance-00000004 | | flavor | m1.tiny | | id | 2eb5e3ad-3044-41c1-bbb7-10f398f83e43 | | security_groups | [{u'name': u'default'}] | | user_id | b3730a52a32e40f0a9500440d1ef1c7d | | OS-DCF:diskConfig | MANUAL | | accessIPv4 | | | accessIPv6 | | | progress | 0 | | OS-EXT-STS:power_state | 0 | | OS-EXT-AZ:availability_zone | nova | | config_drive | | | status | BUILD | | updated | 2014-06-10T00:01:05Z | | hostId | | | OS-EXT-SRV-ATTR:host | None | | key_name | key2 | | OS-EXT-SRV-ATTR:hypervisor_hostname | None | | name | cirros | | adminPass | oFRbvRqif2C8 | | tenant_id | 08cff06d13b74492b780d9ceed699239 | | created | 2014-06-10T00:01:04Z | | metadata | {} | +-------------------------------------+--------------------------------------+ ubuntu@node7:~$ ubuntu@node7:~$ nova list +--------------------------------------+--------+--------+----------+ | ID | Name | Status | Networks | +--------------------------------------+--------+--------+----------+ | 2eb5e3ad-3044-41c1-bbb7-10f398f83e43 | cirros | ERROR | | +--------------------------------------+--------+--------+----------+ ubuntu@node7:~$ var/log/nova/nova-compute.log shows the following error: ... 2014-06-10 00:01:06.048 AUDIT nova.compute.claims [req-41e53086-6454-4efb-bb35-a30dc2c780be b3730a52a32e40f0a9500440d1ef1c7d 08cff06d13b74492b780d9ceed699239] [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] Attempting claim: memory 512 MB, disk 0 GB, VCPUs 1 2014-06-10 00:01:06.049 AUDIT nova.compute.claims [req-41e53086-6454-4efb-bb35-a30dc2c780be b3730a52a32e40f0a9500440d1ef1c7d 08cff06d13b74492b780d9ceed699239] [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] Total Memory: 3885 MB, used: 512 MB 2014-06-10 00:01:06.049 AUDIT nova.compute.claims [req-41e53086-6454-4efb-bb35-a30dc2c780be b3730a52a32e40f0a9500440d1ef1c7d 08cff06d13b74492b780d9ceed699239] [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] Memory limit: 5827 MB, free: 5315 MB 2014-06-10 00:01:06.049 AUDIT nova.compute.claims [req-41e53086-6454-4efb-bb35-a30dc2c780be b3730a52a32e40f0a9500440d1ef1c7d 08cff06d13b74492b780d9ceed699239] [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] Total Disk: 146 GB, used: 0 GB 2014-06-10 00:01:06.050 AUDIT nova.compute.claims [req-41e53086-6454-4efb-bb35-a30dc2c780be b3730a52a32e40f0a9500440d1ef1c7d 08cff06d13b74492b780d9ceed699239] [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] Disk limit not specified, defaulting to unlimited 2014-06-10 00:01:06.050 AUDIT nova.compute.claims [req-41e53086-6454-4efb-bb35-a30dc2c780be b3730a52a32e40f0a9500440d1ef1c7d 08cff06d13b74492b780d9ceed699239] [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] Total CPU: 2 VCPUs, used: 0 VCPUs 2014-06-10 00:01:06.050 AUDIT nova.compute.claims [req-41e53086-6454-4efb-bb35-a30dc2c780be b3730a52a32e40f0a9500440d1ef1c7d 08cff06d13b74492b780d9ceed699239] [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] CPU limit not specified, defaulting to unlimited 2014-06-10 00:01:06.051 AUDIT nova.compute.claims [req-41e53086-6454-4efb-bb35-a30dc2c780be b3730a52a32e40f0a9500440d1ef1c7d 08cff06d13b74492b780d9ceed699239] [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] Claim successful 2014-06-10 00:01:06.963 WARNING nova.network.quantumv2.api [req-41e53086-6454-4efb-bb35-a30dc2c780be b3730a52a32e40f0a9500440d1ef1c7d 08cff06d13b74492b780d9ceed699239] [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] No network configured! 2014-06-10 00:01:08.347 ERROR nova.compute.manager [req-41e53086-6454-4efb-bb35-a30dc2c780be b3730a52a32e40f0a9500440d1ef1c7d 08cff06d13b74492b780d9ceed699239] [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] Instance failed to spawn 2014-06-10 00:01:08.347 32223 TRACE nova.compute.manager [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] Traceback (most recent call last): 2014-06-10 00:01:08.347 32223 TRACE nova.compute.manager [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] File "/usr/lib/python2.7/dist-packages/nova/compute/manager.py", line 1118, in _spawn 2014-06-10 00:01:08.347 32223 TRACE nova.compute.manager [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] self._legacy_nw_info(network_info), 2014-06-10 00:01:08.347 32223 TRACE nova.compute.manager [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] File "/usr/lib/python2.7/dist-packages/nova/compute/manager.py", line 703, in _legacy_nw_info 2014-06-10 00:01:08.347 32223 TRACE nova.compute.manager [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] network_info = network_info.legacy() 2014-06-10 00:01:08.347 32223 TRACE nova.compute.manager [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] AttributeError: 'list' object has no attribute 'legacy' 2014-06-10 00:01:08.347 32223 TRACE nova.compute.manager [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] 2014-06-10 00:01:08.919 AUDIT nova.compute.manager [req-41e53086-6454-4efb-bb35-a30dc2c780be b3730a52a32e40f0a9500440d1ef1c7d 08cff06d13b74492b780d9ceed699239] [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] Terminating instance 2014-06-10 00:01:09.712 32223 ERROR nova.virt.libvirt.driver [-] [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] During wait destroy, instance disappeared. 2014-06-10 00:01:09.718 INFO nova.virt.libvirt.firewall [req-41e53086-6454-4efb-bb35-a30dc2c780be b3730a52a32e40f0a9500440d1ef1c7d 08cff06d13b74492b780d9ceed699239] [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] Attempted to unfilter instance which is not filtered 2014-06-10 00:01:09.719 INFO nova.virt.libvirt.driver [req-41e53086-6454-4efb-bb35-a30dc2c780be b3730a52a32e40f0a9500440d1ef1c7d 08cff06d13b74492b780d9ceed699239] [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] Deleting instance files /var/lib/nova/instances/2eb5e3ad-3044-41c1-bbb7-10f398f83e43 2014-06-10 00:01:10.044 ERROR nova.compute.manager [req-41e53086-6454-4efb-bb35-a30dc2c780be b3730a52a32e40f0a9500440d1ef1c7d 08cff06d13b74492b780d9ceed699239] [instance: 2eb5e3ad-3044-41c1-bbb7-10f398f83e43] Error: ['Traceback (most recent call last):\n', ' File "/usr/lib/python2.7/dist-packages/nova/compute/manager.py", line 864, in _run_instance\n set_access_ip=set_access_ip)\n', ' File "/usr/lib/python2.7/dist-packages/nova/compute/manager.py", line 1123, in _spawn\n LOG.exception(_(\'Instance failed to spawn\'), instance=instance)\n', ' File "/usr/lib/python2.7/contextlib.py", line 24, in __exit__\n self.gen.next()\n', ' File "/usr/lib/python2.7/dist-packages/nova/compute/manager.py", line 1118, in _spawn\n self._legacy_nw_info(network_info),\n', ' File "/usr/lib/python2.7/dist-packages/nova/compute/manager.py", line 703, in _legacy_nw_info\n network_info = network_info.legacy()\n', "AttributeError: 'list' object has no attribute 'legacy'\n"] 2014-06-10 00:01:40.951 32223 AUDIT nova.compute.resource_tracker [-] Auditing locally available compute resources 2014-06-10 00:01:41.072 32223 AUDIT nova.compute.resource_tracker [-] Free ram (MB): 2861 2014-06-10 00:01:41.072 32223 AUDIT nova.compute.resource_tracker [-] Free disk (GB): 146 2014-06-10 00:01:41.073 32223 AUDIT nova.compute.resource_tracker [-] Free VCPUS: 1 2014-06-10 00:01:41.262 32223 INFO nova.compute.resource_tracker [-] Compute_service record updated for node5:node5.maas ... Can't seem to find any entries in quantum.conf related to "legacy". Any help would be appreciated. Cheers,

  Read the article

• Convert ddply {plyr} to Oracle R Enterprise, or use with Embedded R Execution

  - by Mark Hornick

  The plyr package contains a set of tools for partitioning a problem into smaller sub-problems that can be more easily processed. One function within {plyr} is ddply, which allows you to specify subsets of a data.frame and then apply a function to each subset. The result is gathered into a single data.frame. Such a capability is very convenient. The function ddply also has a parallel option that if TRUE, will apply the function in parallel, using the backend provided by foreach. This type of functionality is available through Oracle R Enterprise using the ore.groupApply function. In this blog post, we show a few examples from Sean Anderson's "A quick introduction to plyr" to illustrate the correpsonding functionality using ore.groupApply. To get started, we'll create a demo data set and load the plyr package. set.seed(1) d <- data.frame(year = rep(2000:2014, each = 3),         count = round(runif(45, 0, 20))) dim(d) library(plyr) This first example takes the data frame, partitions it by year, and calculates the coefficient of variation of the count, returning a data frame. # Example 1 res <- ddply(d, "year", function(x) {   mean.count <- mean(x$count)   sd.count <- sd(x$count)   cv <- sd.count/mean.count   data.frame(cv.count = cv)   }) To illustrate the equivalent functionality in Oracle R Enterprise, using embedded R execution, we use the ore.groupApply function on the same data, but pushed to the database, creating an ore.frame. The function ore.push creates a temporary table in the database, returning a proxy object, the ore.frame. D <- ore.push(d) res <- ore.groupApply (D, D$year, function(x) {   mean.count <- mean(x$count)   sd.count <- sd(x$count)   cv <- sd.count/mean.count   data.frame(year=x$year[1], cv.count = cv)   }, FUN.VALUE=data.frame(year=1, cv.count=1)) You'll notice the similarities in the first three arguments. With ore.groupApply, we augment the function to return the specific data.frame we want. We also specify the argument FUN.VALUE, which describes the resulting data.frame. From our previous blog posts, you may recall that by default, ore.groupApply returns an ore.list containing the results of each function invocation. To get a data.frame, we specify the structure of the result. The results in both cases are the same, however the ore.groupApply result is an ore.frame. In this case the data stays in the database until it's actually required. This can result in significant memory and time savings whe data is large. R> class(res) [1] "ore.frame" attr(,"package") [1] "OREbase" R> head(res)    year cv.count 1 2000 0.3984848 2 2001 0.6062178 3 2002 0.2309401 4 2003 0.5773503 5 2004 0.3069680 6 2005 0.3431743 To make the ore.groupApply execute in parallel, you can specify the argument parallel with either TRUE, to use default database parallelism, or to a specific number, which serves as a hint to the database as to how many parallel R engines should be used. The next ddply example uses the summarise function, which creates a new data.frame. In ore.groupApply, the year column is passed in with the data. Since no automatic creation of columns takes place, we explicitly set the year column in the data.frame result to the value of the first row, since all rows received by the function have the same year. # Example 2 ddply(d, "year", summarise, mean.count = mean(count)) res <- ore.groupApply (D, D$year, function(x) {   mean.count <- mean(x$count)   data.frame(year=x$year[1], mean.count = mean.count)   }, FUN.VALUE=data.frame(year=1, mean.count=1)) R> head(res)    year mean.count 1 2000 7.666667 2 2001 13.333333 3 2002 15.000000 4 2003 3.000000 5 2004 12.333333 6 2005 14.666667 Example 3 uses the transform function with ddply, which modifies the existing data.frame. With ore.groupApply, we again construct the data.frame explicilty, which is returned as an ore.frame. # Example 3 ddply(d, "year", transform, total.count = sum(count)) res <- ore.groupApply (D, D$year, function(x) {   total.count <- sum(x$count)   data.frame(year=x$year[1], count=x$count, total.count = total.count)   }, FUN.VALUE=data.frame(year=1, count=1, total.count=1)) > head(res)    year count total.count 1 2000 5 23 2 2000 7 23 3 2000 11 23 4 2001 18 40 5 2001 4 40 6 2001 18 40 In Example 4, the mutate function with ddply enables you to define new columns that build on columns just defined. Since the construction of the data.frame using ore.groupApply is explicit, you always have complete control over when and how to use columns. # Example 4 ddply(d, "year", mutate, mu = mean(count), sigma = sd(count),       cv = sigma/mu) res <- ore.groupApply (D, D$year, function(x) {   mu <- mean(x$count)   sigma <- sd(x$count)   cv <- sigma/mu   data.frame(year=x$year[1], count=x$count, mu=mu, sigma=sigma, cv=cv)   }, FUN.VALUE=data.frame(year=1, count=1, mu=1,sigma=1,cv=1)) R> head(res)    year count mu sigma cv 1 2000 5 7.666667 3.055050 0.3984848 2 2000 7 7.666667 3.055050 0.3984848 3 2000 11 7.666667 3.055050 0.3984848 4 2001 18 13.333333 8.082904 0.6062178 5 2001 4 13.333333 8.082904 0.6062178 6 2001 18 13.333333 8.082904 0.6062178 In Example 5, ddply is used to partition data on multiple columns before constructing the result. Realizing this with ore.groupApply involves creating an index column out of the concatenation of the columns used for partitioning. This example also allows us to illustrate using the ORE transparency layer to subset the data. # Example 5 baseball.dat <- subset(baseball, year > 2000) # data from the plyr package x <- ddply(baseball.dat, c("year", "team"), summarize,            homeruns = sum(hr)) We first push the data set to the database to get an ore.frame. We then add the composite column and perform the subset, using the transparency layer. Since the results from database execution are unordered, we will explicitly sort these results and view the first 6 rows. BB.DAT <- ore.push(baseball) BB.DAT$index <- with(BB.DAT, paste(year, team, sep="+")) BB.DAT2 <- subset(BB.DAT, year > 2000) X <- ore.groupApply (BB.DAT2, BB.DAT2$index, function(x) {   data.frame(year=x$year[1], team=x$team[1], homeruns=sum(x$hr))   }, FUN.VALUE=data.frame(year=1, team="A", homeruns=1), parallel=FALSE) res <- ore.sort(X, by=c("year","team")) R> head(res)    year team homeruns 1 2001 ANA 4 2 2001 ARI 155 3 2001 ATL 63 4 2001 BAL 58 5 2001 BOS 77 6 2001 CHA 63 Our next example is derived from the ggplot function documentation. This illustrates the use of ddply within using the ggplot2 package. We first create a data.frame with demo data and use ddply to create some statistics for each group (gp). We then use ggplot to produce the graph. We can take this same code, push the data.frame df to the database and invoke this on the database server. The graph will be returned to the client window, as depicted below. # Example 6 with ggplot2 library(ggplot2) df <- data.frame(gp = factor(rep(letters[1:3], each = 10)),                  y = rnorm(30)) # Compute sample mean and standard deviation in each group library(plyr) ds <- ddply(df, .(gp), summarise, mean = mean(y), sd = sd(y)) # Set up a skeleton ggplot object and add layers: ggplot() +   geom_point(data = df, aes(x = gp, y = y)) +   geom_point(data = ds, aes(x = gp, y = mean),              colour = 'red', size = 3) +   geom_errorbar(data = ds, aes(x = gp, y = mean,                                ymin = mean - sd, ymax = mean + sd),              colour = 'red', width = 0.4) DF <- ore.push(df) ore.tableApply(DF, function(df) {   library(ggplot2)   library(plyr)   ds <- ddply(df, .(gp), summarise, mean = mean(y), sd = sd(y))   ggplot() +     geom_point(data = df, aes(x = gp, y = y)) +     geom_point(data = ds, aes(x = gp, y = mean),                colour = 'red', size = 3) +     geom_errorbar(data = ds, aes(x = gp, y = mean,                                  ymin = mean - sd, ymax = mean + sd),                   colour = 'red', width = 0.4) }) But let's take this one step further. Suppose we wanted to produce multiple graphs, partitioned on some index column. We replicate the data three times and add some noise to the y values, just to make the graphs a little different. We also create an index column to form our three partitions. Note that we've also specified that this should be executed in parallel, allowing Oracle Database to control and manage the server-side R engines. The result of ore.groupApply is an ore.list that contains the three graphs. Each graph can be viewed by printing the list element. df2 <- rbind(df,df,df) df2$y <- df2$y + rnorm(nrow(df2)) df2$index <- c(rep(1,300), rep(2,300), rep(3,300)) DF2 <- ore.push(df2) res <- ore.groupApply(DF2, DF2$index, function(df) {   df <- df[,1:2]   library(ggplot2)   library(plyr)   ds <- ddply(df, .(gp), summarise, mean = mean(y), sd = sd(y))   ggplot() +     geom_point(data = df, aes(x = gp, y = y)) +     geom_point(data = ds, aes(x = gp, y = mean),                colour = 'red', size = 3) +     geom_errorbar(data = ds, aes(x = gp, y = mean,                                  ymin = mean - sd, ymax = mean + sd),                   colour = 'red', width = 0.4)   }, parallel=TRUE) res[[1]] res[[2]] res[[3]] To recap, we've illustrated how various uses of ddply from the plyr package can be realized in ore.groupApply, which affords the user explicit control over the contents of the data.frame result in a straightforward manner. We've also highlighted how ddply can be used within an ore.groupApply call.

  Read the article

• Vertex buffer acting strange? [on hold]

  - by Ryan Capote

  I'm having a strange problem, and I don't know what could be causing it. My current code is identical to how I've done this before. I'm trying to render a rectangle using VBO and orthographic projection.   My results:     What I expect: 3x3 rectangle in the top left corner   #include <stdio.h> #include <GL\glew.h> #include <GLFW\glfw3.h> #include "lodepng.h"   static const int FALSE = 0; static const int TRUE = 1;   static const char* VERT_SHADER =     "#version 330\n"       "layout(location=0) in vec4 VertexPosition; "     "layout(location=1) in vec2 UV;"     "uniform mat4 uProjectionMatrix;"     /*"out vec2 TexCoords;"*/       "void main(void) {"     "    gl_Position = uProjectionMatrix*VertexPosition;"     /*"    TexCoords = UV;"*/     "}";   static const char* FRAG_SHADER =     "#version 330\n"       /*"uniform sampler2D uDiffuseTexture;"     "uniform vec4 uColor;"     "in vec2 TexCoords;"*/     "out vec4 FragColor;"       "void main(void) {"    /* "    vec4 texel = texture2D(uDiffuseTexture, TexCoords);"     "    if(texel.a <= 0) {"     "         discard;"     "    }"     "    FragColor = texel;"*/     "    FragColor = vec4(1.f);"     "}";   static int g_running; static GLFWwindow *gl_window; static float gl_projectionMatrix[16];   /*     Structures */ typedef struct _Vertex {     float x, y, z, w;     float u, v; } Vertex;   typedef struct _Position {     float x, y; } Position;   typedef struct _Bitmap {     unsigned char *pixels;     unsigned int width, height; } Bitmap;   typedef struct _Texture {     GLuint id;     unsigned int width, height; } Texture;   typedef struct _VertexBuffer {     GLuint bufferObj, vertexArray; } VertexBuffer;   typedef struct _ShaderProgram {     GLuint vertexShader, fragmentShader, program; } ShaderProgram;   /*   http://en.wikipedia.org/wiki/Orthographic_projection */ void createOrthoProjection(float *projection, float width, float height, float far, float near)  {       const float left = 0;     const float right = width;     const float top = 0;     const float bottom = height;          projection[0] = 2.f / (right - left);     projection[1] = 0.f;     projection[2] = 0.f;     projection[3] = -(right+left) / (right-left);     projection[4] = 0.f;     projection[5] = 2.f / (top - bottom);     projection[6] = 0.f;     projection[7] = -(top + bottom) / (top - bottom);     projection[8] = 0.f;     projection[9] = 0.f;     projection[10] = -2.f / (far-near);     projection[11] = (far+near)/(far-near);     projection[12] = 0.f;     projection[13] = 0.f;     projection[14] = 0.f;     projection[15] = 1.f; }   /*     Textures */ void loadBitmap(const char *filename, Bitmap *bitmap, int *success) {     int error = lodepng_decode32_file(&bitmap->pixels, &bitmap->width, &bitmap->height, filename);       if (error != 0) {         printf("Failed to load bitmap. ");         printf(lodepng_error_text(error));         success = FALSE;         return;     } }   void destroyBitmap(Bitmap *bitmap) {     free(bitmap->pixels); }   void createTexture(Texture *texture, const Bitmap *bitmap) {     texture->id = 0;     glGenTextures(1, &texture->id);     glBindTexture(GL_TEXTURE_2D, texture);       glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);     glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);       glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, bitmap->width, bitmap->height, 0,              GL_RGBA, GL_UNSIGNED_BYTE, bitmap->pixels);       glBindTexture(GL_TEXTURE_2D, 0); }   void destroyTexture(Texture *texture) {     glDeleteTextures(1, &texture->id);     texture->id = 0; }   /*     Vertex Buffer */ void createVertexBuffer(VertexBuffer *vertexBuffer, Vertex *vertices) {     glGenBuffers(1, &vertexBuffer->bufferObj);     glGenVertexArrays(1, &vertexBuffer->vertexArray);     glBindVertexArray(vertexBuffer->vertexArray);       glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer->bufferObj);     glBufferData(GL_ARRAY_BUFFER, sizeof(Vertex) * 6, (const GLvoid*)vertices, GL_STATIC_DRAW);       const unsigned int uvOffset = sizeof(float) * 4;       glVertexAttribPointer(0, 4, GL_FLOAT, GL_FALSE, sizeof(Vertex), 0);     glVertexAttribPointer(1, 2, GL_FLOAT, GL_FALSE, sizeof(Vertex), (GLvoid*)uvOffset);       glEnableVertexAttribArray(0);     glEnableVertexAttribArray(1);       glBindBuffer(GL_ARRAY_BUFFER, 0);     glBindVertexArray(0); }   void destroyVertexBuffer(VertexBuffer *vertexBuffer) {     glDeleteBuffers(1, &vertexBuffer->bufferObj);     glDeleteVertexArrays(1, &vertexBuffer->vertexArray); }   void bindVertexBuffer(VertexBuffer *vertexBuffer) {     glBindVertexArray(vertexBuffer->vertexArray);     glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer->bufferObj); }   void drawVertexBufferMode(GLenum mode) {     glDrawArrays(mode, 0, 6); }   void drawVertexBuffer() {     drawVertexBufferMode(GL_TRIANGLES); }   void unbindVertexBuffer() {     glBindVertexArray(0);     glBindBuffer(GL_ARRAY_BUFFER, 0); }   /*     Shaders */ void compileShader(ShaderProgram *shaderProgram, const char *vertexSrc, const char *fragSrc) {     GLenum err;     shaderProgram->vertexShader = glCreateShader(GL_VERTEX_SHADER);     shaderProgram->fragmentShader = glCreateShader(GL_FRAGMENT_SHADER);       if (shaderProgram->vertexShader == 0) {         printf("Failed to create vertex shader.");         return;     }       if (shaderProgram->fragmentShader == 0) {         printf("Failed to create fragment shader.");         return;     }       glShaderSource(shaderProgram->vertexShader, 1, &vertexSrc, NULL);     glCompileShader(shaderProgram->vertexShader);     glGetShaderiv(shaderProgram->vertexShader, GL_COMPILE_STATUS, &err);       if (err != GL_TRUE) {         printf("Failed to compile vertex shader.");         return;     }       glShaderSource(shaderProgram->fragmentShader, 1, &fragSrc, NULL);     glCompileShader(shaderProgram->fragmentShader);     glGetShaderiv(shaderProgram->fragmentShader, GL_COMPILE_STATUS, &err);       if (err != GL_TRUE) {         printf("Failed to compile fragment shader.");         return;     }       shaderProgram->program = glCreateProgram();     glAttachShader(shaderProgram->program, shaderProgram->vertexShader);     glAttachShader(shaderProgram->program, shaderProgram->fragmentShader);     glLinkProgram(shaderProgram->program);          glGetProgramiv(shaderProgram->program, GL_LINK_STATUS, &err);       if (err != GL_TRUE) {         printf("Failed to link shader.");         return;     } }   void destroyShader(ShaderProgram *shaderProgram) {     glDetachShader(shaderProgram->program, shaderProgram->vertexShader);     glDetachShader(shaderProgram->program, shaderProgram->fragmentShader);       glDeleteShader(shaderProgram->vertexShader);     glDeleteShader(shaderProgram->fragmentShader);       glDeleteProgram(shaderProgram->program); }   GLuint getUniformLocation(const char *name, ShaderProgram *program) {     GLuint result = 0;     result = glGetUniformLocation(program->program, name);       return result; }   void setUniformMatrix(float *matrix, const char *name, ShaderProgram *program) {     GLuint loc = getUniformLocation(name, program);       if (loc == -1) {         printf("Failed to get uniform location in setUniformMatrix.\n");         return;     }       glUniformMatrix4fv(loc, 1, GL_FALSE, matrix); }   /*     General functions */ static int isRunning() {     return g_running && !glfwWindowShouldClose(gl_window); }   static void initializeGLFW(GLFWwindow **window, int width, int height, int *success) {     if (!glfwInit()) {         printf("Failed it inialize GLFW.");         *success = FALSE;        return;     }          glfwWindowHint(GLFW_RESIZABLE, 0);     *window = glfwCreateWindow(width, height, "Alignments", NULL, NULL);          if (!*window) {         printf("Failed to create window.");         glfwTerminate();         *success = FALSE;         return;     }          glfwMakeContextCurrent(*window);       GLenum glewErr = glewInit();     if (glewErr != GLEW_OK) {         printf("Failed to initialize GLEW.");         printf(glewGetErrorString(glewErr));         *success = FALSE;         return;     }       glClearColor(0.f, 0.f, 0.f, 1.f);     glViewport(0, 0, width, height);     *success = TRUE; }   int main(int argc, char **argv) {          int err = FALSE;     initializeGLFW(&gl_window, 480, 320, &err);     glDisable(GL_DEPTH_TEST);     if (err == FALSE) {         return 1;     }          createOrthoProjection(gl_projectionMatrix, 480.f, 320.f, 0.f, 1.f);          g_running = TRUE;          ShaderProgram shader;     compileShader(&shader, VERT_SHADER, FRAG_SHADER);     glUseProgram(shader.program);     setUniformMatrix(&gl_projectionMatrix, "uProjectionMatrix", &shader);       Vertex rectangle[6];     VertexBuffer vbo;     rectangle[0] = (Vertex){0.f, 0.f, 0.f, 1.f, 0.f, 0.f}; // Top left     rectangle[1] = (Vertex){3.f, 0.f, 0.f, 1.f, 1.f, 0.f}; // Top right     rectangle[2] = (Vertex){0.f, 3.f, 0.f, 1.f, 0.f, 1.f}; // Bottom left     rectangle[3] = (Vertex){3.f, 0.f, 0.f, 1.f, 1.f, 0.f}; // Top left     rectangle[4] = (Vertex){0.f, 3.f, 0.f, 1.f, 0.f, 1.f}; // Bottom left     rectangle[5] = (Vertex){3.f, 3.f, 0.f, 1.f, 1.f, 1.f}; // Bottom right       createVertexBuffer(&vbo, &rectangle);            bindVertexBuffer(&vbo);          while (isRunning()) {         glClear(GL_COLOR_BUFFER_BIT);         glfwPollEvents();                    drawVertexBuffer();                    glfwSwapBuffers(gl_window);     }          unbindVertexBuffer(&vbo);       glUseProgram(0);     destroyShader(&shader);     destroyVertexBuffer(&vbo);     glfwTerminate();     return 0; }

  Read the article

• Building a better mouse-trap &ndash; Improving the creation of XML Message Requests using Reflection, XML &amp; XSLT

  - by paulschapman

  Introduction The way I previously created messages to send to the GovTalk service I used the XMLDocument to create the request. While this worked it left a number of problems; not least that for every message a special function would need to created. This is OK for the short term but the biggest cost in any software project is maintenance and this would be a headache to maintain. So the following is a somewhat better way of achieving the same thing. For the purposes of this article I am going to be using the CompanyNumberSearch request of the GovTalk service – although this technique would work for any service that accepted XML. The C# functions which send and receive the messages remain the same. The magic sauce in this is the XSLT which defines the structure of the request, and the use of objects in conjunction with reflection to provide the content. It is a bit like Sweet Chilli Sauce added to Chicken on a bed of rice. So on to the Sweet Chilli Sauce The Sweet Chilli Sauce The request to search for a company based on it’s number is as follows; <GovTalkMessage xsi:schemaLocation="http://www.govtalk.gov.uk/CM/envelope http://xmlgw.companieshouse.gov.uk/v1-0/schema/Egov_ch-v2-0.xsd" xmlns="http://www.govtalk.gov.uk/CM/envelope" xmlns:dsig="http://www.w3.org/2000/09/xmldsig#" xmlns:gt="http://www.govtalk.gov.uk/schemas/govtalk/core" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" > <EnvelopeVersion>1.0</EnvelopeVersion> <Header> <MessageDetails> <Class>NumberSearch</Class> <Qualifier>request</Qualifier> <TransactionID>1</TransactionID> </MessageDetails> <SenderDetails> <IDAuthentication> <SenderID>????????????????????????????????</SenderID> <Authentication> <Method>CHMD5</Method> <Value>????????????????????????????????</Value> </Authentication> </IDAuthentication> </SenderDetails> </Header> <GovTalkDetails> <Keys/> </GovTalkDetails> <Body> <NumberSearchRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="http://xmlgw.companieshouse.gov.uk/v1-0/schema/NumberSearch.xsd"> <PartialCompanyNumber>99999999</PartialCompanyNumber> <DataSet>LIVE</DataSet> <SearchRows>1</SearchRows> </NumberSearchRequest> </Body> </GovTalkMessage> This is the XML that we send to the GovTalk Service and we get back a list of companies that match the criteria passed A message is structured in two parts; The envelope which identifies the person sending the request, with the name of the request, and the body which gives the detail of the company we are looking for. The Chilli What makes it possible is the use of XSLT to define the message – and serialization to convert each request object into XML. To start we need to create an object which will represent the contents of the message we are sending. However there is a common properties in all the messages that we send to Companies House. These properties are as follows SenderId – the id of the person sending the message SenderPassword – the password associated with Id TransactionId – Unique identifier for the message AuthenticationValue – authenticates the request Because these properties are unique to the Companies House message, and because they are shared with all messages they are perfect candidates for a base class. The class is as follows; using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.Security.Cryptography; using System.Text; using System.Text.RegularExpressions; using Microsoft.WindowsAzure.ServiceRuntime; namespace CompanyHub.Services { public class GovTalkRequest { public GovTalkRequest() { try { SenderID = RoleEnvironment.GetConfigurationSettingValue("SenderId"); SenderPassword = RoleEnvironment.GetConfigurationSettingValue("SenderPassword"); TransactionId = DateTime.Now.Ticks.ToString(); AuthenticationValue = EncodePassword(String.Format("{0}{1}{2}", SenderID, SenderPassword, TransactionId)); } catch (System.Exception ex) { throw ex; } } /// <summary> /// returns the Sender ID to be used when communicating with the GovTalk Service /// </summary> public String SenderID { get; set; } /// <summary> /// return the password to be used when communicating with the GovTalk Service /// </summary> public String SenderPassword { get; set; } // end SenderPassword /// <summary> /// Transaction Id - uses the Time and Date converted to Ticks /// </summary> public String TransactionId { get; set; } // end TransactionId /// <summary> /// calculate the authentication value that will be used when /// communicating with /// </summary> public String AuthenticationValue { get; set; } // end AuthenticationValue property /// <summary> /// encodes password(s) using MD5 /// </summary> /// <param name="clearPassword"></param> /// <returns></returns> public static String EncodePassword(String clearPassword) { MD5CryptoServiceProvider md5Hasher = new MD5CryptoServiceProvider(); byte[] hashedBytes; UTF32Encoding encoder = new UTF32Encoding(); hashedBytes = md5Hasher.ComputeHash(ASCIIEncoding.Default.GetBytes(clearPassword)); String result = Regex.Replace(BitConverter.ToString(hashedBytes), "-", "").ToLower(); return result; } } } There is nothing particularly clever here, except for the EncodePassword method which hashes the value made up of the SenderId, Password and Transaction id. Each message inherits from this object. So for the Company Number Search in addition to the properties above we need a partial number, which dataset to search – for the purposes of the project we only need to search the LIVE set so this can be set in the constructor and the SearchRows. Again all are set as properties. With the SearchRows and DataSet initialized in the constructor. public class CompanyNumberSearchRequest : GovTalkRequest, IDisposable { /// <summary> /// /// </summary> public CompanyNumberSearchRequest() : base() { DataSet = "LIVE"; SearchRows = 1; } /// <summary> /// Company Number to search against /// </summary> public String PartialCompanyNumber { get; set; } /// <summary> /// What DataSet should be searched for the company /// </summary> public String DataSet { get; set; } /// <summary> /// How many rows should be returned /// </summary> public int SearchRows { get; set; } public void Dispose() { DataSet = String.Empty; PartialCompanyNumber = String.Empty; DataSet = "LIVE"; SearchRows = 1; } } As well as inheriting from our base class, I have also inherited from IDisposable – not just because it is just plain good practice to dispose of objects when coding, but it gives also gives us more versatility when using the object. There are four stages in making a request and this is reflected in the four methods we execute in making a call to the Companies House service; Create a request Send a request Check the status If OK then get the results of the request I’ve implemented each of these stages within a static class called Toolbox – which also means I don’t need to create an instance of the class to use it. When making a request there are three stages; Get the template for the message Serialize the object representing the message Transform the serialized object using a predefined XSLT file. Each of my templates I have defined as an embedded resource. When retrieving a resource of this kind we have to include the full namespace to the resource. In making the code re-usable as much as possible I defined the full ‘path’ within the GetRequest method. requestFile = String.Format("CompanyHub.Services.Schemas.{0}", RequestFile); So we now have the full path of the file within the assembly. Now all we need do is retrieve the assembly and get the resource. asm = Assembly.GetExecutingAssembly(); sr = asm.GetManifestResourceStream(requestFile); Once retrieved  So this can be returned to the calling function and we now have a stream of XSLT to define the message. Time now to serialize the request to create the other side of this message. // Serialize object containing Request, Load into XML Document t = Obj.GetType(); ms = new MemoryStream(); serializer = new XmlSerializer(t); xmlTextWriter = new XmlTextWriter(ms, Encoding.ASCII); serializer.Serialize(xmlTextWriter, Obj); ms = (MemoryStream)xmlTextWriter.BaseStream; GovTalkRequest = Toolbox.ConvertByteArrayToString(ms.ToArray()); First off we need the type of the object so we make a call to the GetType method of the object containing the Message properties. Next we need a MemoryStream, XmlSerializer and an XMLTextWriter so these can be initialized. The object is serialized by making the call to the Serialize method of the serializer object. The result of that is then converted into a MemoryStream. That MemoryStream is then converted into a string. ConvertByteArrayToString This is a fairly simple function which uses an ASCIIEncoding object found within the System.Text namespace to convert an array of bytes into a string. public static String ConvertByteArrayToString(byte[] bytes) { System.Text.ASCIIEncoding enc = new System.Text.ASCIIEncoding(); return enc.GetString(bytes); } I only put it into a function because I will be using this in various places. The Sauce When adding support for other messages outside of creating a new object to store the properties of the message, the C# components do not need to change. It is in the XSLT file that the versatility of the technique lies. The XSLT file determines the format of the message. For the CompanyNumberSearch the XSLT file is as follows; <?xml version="1.0"?> <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform"> <xsl:template match="/"> <GovTalkMessage xsi:schemaLocation="http://www.govtalk.gov.uk/CM/envelope http://xmlgw.companieshouse.gov.uk/v1-0/schema/Egov_ch-v2-0.xsd" xmlns="http://www.govtalk.gov.uk/CM/envelope" xmlns:dsig="http://www.w3.org/2000/09/xmldsig#" xmlns:gt="http://www.govtalk.gov.uk/schemas/govtalk/core" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" > <EnvelopeVersion>1.0</EnvelopeVersion> <Header> <MessageDetails> <Class>NumberSearch</Class> <Qualifier>request</Qualifier> <TransactionID> <xsl:value-of select="CompanyNumberSearchRequest/TransactionId"/> </TransactionID> </MessageDetails> <SenderDetails> <IDAuthentication> <SenderID><xsl:value-of select="CompanyNumberSearchRequest/SenderID"/></SenderID> <Authentication> <Method>CHMD5</Method> <Value> <xsl:value-of select="CompanyNumberSearchRequest/AuthenticationValue"/> </Value> </Authentication> </IDAuthentication> </SenderDetails> </Header> <GovTalkDetails> <Keys/> </GovTalkDetails> <Body> <NumberSearchRequest xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="http://xmlgw.companieshouse.gov.uk/v1-0/schema/NumberSearch.xsd"> <PartialCompanyNumber> <xsl:value-of select="CompanyNumberSearchRequest/PartialCompanyNumber"/> </PartialCompanyNumber> <DataSet> <xsl:value-of select="CompanyNumberSearchRequest/DataSet"/> </DataSet> <SearchRows> <xsl:value-of select="CompanyNumberSearchRequest/SearchRows"/> </SearchRows> </NumberSearchRequest> </Body> </GovTalkMessage> </xsl:template> </xsl:stylesheet> The outer two tags define that this is a XSLT stylesheet and the root tag from which the nodes are searched for. The GovTalkMessage is the format of the message that will be sent to Companies House. We first set up the XslCompiledTransform object which will transform the XSLT template and the serialized object into the request to Companies House. xslt = new XslCompiledTransform(); resultStream = new MemoryStream(); writer = new XmlTextWriter(resultStream, Encoding.ASCII); doc = new XmlDocument(); The Serialize method require XmlTextWriter to write the XML (writer) and a stream to place the transferred object into (writer). The XML will be loaded into an XMLDocument object (doc) prior to the transformation. // create XSLT Template xslTemplate = Toolbox.GetRequest(Template); xslTemplate.Seek(0, SeekOrigin.Begin); templateReader = XmlReader.Create(xslTemplate); xslt.Load(templateReader); I have stored all the templates as a series of Embedded Resources and the GetRequestCall takes the name of the template and extracts the relevent XSLT file. /// <summary> /// Gets the framwork XML which makes the request /// </summary> /// <param name="RequestFile"></param> /// <returns></returns> public static Stream GetRequest(String RequestFile) { String requestFile = String.Empty; Stream sr = null; Assembly asm = null; try { requestFile = String.Format("CompanyHub.Services.Schemas.{0}", RequestFile); asm = Assembly.GetExecutingAssembly(); sr = asm.GetManifestResourceStream(requestFile); } catch (Exception) { throw; } finally { asm = null; } return sr; } // end private static stream GetRequest We first take the template name and expand it to include the full namespace to the Embedded Resource I like to keep all my schemas in the same directory and so the namespace reflects this. The rest is the default namespace for the project. Then we get the currently executing assembly (which will contain the resources with the call to GetExecutingAssembly() ) Finally we get a stream which contains the XSLT file. We use this stream and then load an XmlReader with the contents of the template, and that is in turn loaded into the XslCompiledTransform object. We convert the object containing the message properties into Xml by serializing it; calling the Serialize() method of the XmlSerializer object. To set up the object we do the following; t = Obj.GetType(); ms = new MemoryStream(); serializer = new XmlSerializer(t); xmlTextWriter = new XmlTextWriter(ms, Encoding.ASCII); We first determine the type of the object being transferred by calling GetType() We create an XmlSerializer object by passing the type of the object being serialized. The serializer writes to a memory stream and that is linked to an XmlTextWriter. Next job is to serialize the object and load it into an XmlDocument. serializer.Serialize(xmlTextWriter, Obj); ms = (MemoryStream)xmlTextWriter.BaseStream; xmlRequest = new XmlTextReader(ms); GovTalkRequest = Toolbox.ConvertByteArrayToString(ms.ToArray()); doc.LoadXml(GovTalkRequest); Time to transform the XML to construct the full request. xslt.Transform(doc, writer); resultStream.Seek(0, SeekOrigin.Begin); request = Toolbox.ConvertByteArrayToString(resultStream.ToArray()); So that creates the full request to be sent  to Companies House. Sending the request So far we have a string with a request for the Companies House service. Now we need to send the request to the Companies House Service. Configuration within an Azure project There are entire blog entries written about configuration within an Azure project – most of this is out of scope for this article but the following is a summary. Configuration is defined in two files within the parent project *.csdef which contains the definition of configuration setting. <?xml version="1.0" encoding="utf-8"?> <ServiceDefinition name="OnlineCompanyHub" xmlns="http://schemas.microsoft.com/ServiceHosting/2008/10/ServiceDefinition"> <WebRole name="CompanyHub.Host"> <InputEndpoints> <InputEndpoint name="HttpIn" protocol="http" port="80" /> </InputEndpoints> <ConfigurationSettings> <Setting name="DiagnosticsConnectionString" /> <Setting name="DataConnectionString" /> </ConfigurationSettings> </WebRole> <WebRole name="CompanyHub.Services"> <InputEndpoints> <InputEndpoint name="HttpIn" protocol="http" port="8080" /> </InputEndpoints> <ConfigurationSettings> <Setting name="DiagnosticsConnectionString" /> <Setting name="SenderId"/> <Setting name="SenderPassword" /> <Setting name="GovTalkUrl"/> </ConfigurationSettings> </WebRole> <WorkerRole name="CompanyHub.Worker"> <ConfigurationSettings> <Setting name="DiagnosticsConnectionString" /> </ConfigurationSettings> </WorkerRole> </ServiceDefinition>   Above is the configuration definition from the project. What we are interested in however is the ConfigurationSettings tag of the CompanyHub.Services WebRole. There are four configuration settings here, but at the moment we are interested in the second to forth settings; SenderId, SenderPassword and GovTalkUrl The value of these settings are defined in the ServiceDefinition.cscfg file; <?xml version="1.0"?> <ServiceConfiguration serviceName="OnlineCompanyHub" xmlns="http://schemas.microsoft.com/ServiceHosting/2008/10/ServiceConfiguration"> <Role name="CompanyHub.Host"> <Instances count="2" /> <ConfigurationSettings> <Setting name="DiagnosticsConnectionString" value="UseDevelopmentStorage=true" /> <Setting name="DataConnectionString" value="UseDevelopmentStorage=true" /> </ConfigurationSettings> </Role> <Role name="CompanyHub.Services"> <Instances count="2" /> <ConfigurationSettings> <Setting name="DiagnosticsConnectionString" value="UseDevelopmentStorage=true" /> <Setting name="SenderId" value="UserID"/> <Setting name="SenderPassword" value="Password"/> <Setting name="GovTalkUrl" value="http://xmlgw.companieshouse.gov.uk/v1-0/xmlgw/Gateway"/> </ConfigurationSettings> </Role> <Role name="CompanyHub.Worker"> <Instances count="2" /> <ConfigurationSettings> <Setting name="DiagnosticsConnectionString" value="UseDevelopmentStorage=true" /> </ConfigurationSettings> </Role> </ServiceConfiguration>   Look for the Role tag that contains our project name (CompanyHub.Services). Having configured the parameters we can now transmit the request. This is done by ‘POST’ing a stream of XML to the Companies House servers. govTalkUrl = RoleEnvironment.GetConfigurationSettingValue("GovTalkUrl"); request = WebRequest.Create(govTalkUrl); request.Method = "POST"; request.ContentType = "text/xml"; writer = new StreamWriter(request.GetRequestStream()); writer.WriteLine(RequestMessage); writer.Close(); We use the WebRequest object to send the object. Set the method of sending to ‘POST’ and the type of data as text/xml. Once set up all we do is write the request to the writer – this sends the request to Companies House. Did the Request Work Part I – Getting the response Having sent a request – we now need the result of that request. response = request.GetResponse(); reader = response.GetResponseStream(); result = Toolbox.ConvertByteArrayToString(Toolbox.ReadFully(reader));   The WebRequest object has a GetResponse() method which allows us to get the response sent back. Like many of these calls the results come in the form of a stream which we convert into a string. Did the Request Work Part II – Translating the Response Much like XSLT and XML were used to create the original request, so it can be used to extract the response and by deserializing the result we create an object that contains the response. Did it work? It would be really great if everything worked all the time. Of course if it did then I don’t suppose people would pay me and others the big bucks so that our programmes do not a) Collapse in a heap (this is an area of memory) b) Blow every fuse in the place in a shower of sparks (this will probably not happen this being real life and not a Hollywood movie, but it was possible to blow the sound system of a BBC Model B with a poorly coded setting) c) Go nuts and trap everyone outside the airlock (this was from a movie, and unless NASA get a manned moon/mars mission set up unlikely to happen) d) Go nuts and take over the world (this was also from a movie, but please note life has a habit of being of exceeding the wildest imaginations of Hollywood writers (note writers – Hollywood executives have no imagination and judging by recent output of that town have turned plagiarism into an art form). e) Freeze in total confusion because the cleaner pulled the plug to the internet router (this has happened) So anyway – we need to check to see if our request actually worked. Within the GovTalk response there is a section that details the status of the message and a description of what went wrong (if anything did). I have defined an XSLT template which will extract these into an XML document. <?xml version="1.0"?> <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:ev="http://www.govtalk.gov.uk/CM/envelope" xmlns:gt="http://www.govtalk.gov.uk/schemas/govtalk/core" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"> <xsl:template match="/"> <GovTalkStatus xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"> <Status> <xsl:value-of select="ev:GovTalkMessage/ev:Header/ev:MessageDetails/ev:Qualifier"/> </Status> <Text> <xsl:value-of select="ev:GovTalkMessage/ev:GovTalkDetails/ev:GovTalkErrors/ev:Error/ev:Text"/> </Text> <Location> <xsl:value-of select="ev:GovTalkMessage/ev:GovTalkDetails/ev:GovTalkErrors/ev:Error/ev:Location"/> </Location> <Number> <xsl:value-of select="ev:GovTalkMessage/ev:GovTalkDetails/ev:GovTalkErrors/ev:Error/ev:Number"/> </Number> <Type> <xsl:value-of select="ev:GovTalkMessage/ev:GovTalkDetails/ev:GovTalkErrors/ev:Error/ev:Type"/> </Type> </GovTalkStatus> </xsl:template> </xsl:stylesheet>   Only thing different about previous XSL files is the references to two namespaces ev & gt. These are defined in the GovTalk response at the top of the response; xsi:schemaLocation="http://www.govtalk.gov.uk/CM/envelope http://xmlgw.companieshouse.gov.uk/v1-0/schema/Egov_ch-v2-0.xsd" xmlns="http://www.govtalk.gov.uk/CM/envelope" xmlns:dsig="http://www.w3.org/2000/09/xmldsig#" xmlns:gt="http://www.govtalk.gov.uk/schemas/govtalk/core" If we do not put these references into the XSLT template then  the XslCompiledTransform object will not be able to find the relevant tags. Deserialization is a fairly simple activity. encoder = new ASCIIEncoding(); ms = new MemoryStream(encoder.GetBytes(statusXML)); serializer = new XmlSerializer(typeof(GovTalkStatus)); xmlTextWriter = new XmlTextWriter(ms, Encoding.ASCII); messageStatus = (GovTalkStatus)serializer.Deserialize(ms);   We set up a serialization object using the object type containing the error state and pass to it the results of a transformation between the XSLT above and the GovTalk response. Now we have an object containing any error state, and the error message. All we need to do is check the status. If there is an error then we can flag an error. If not then  we extract the results and pass that as an object back to the calling function. We go this by guess what – defining an XSLT template for the result and using that to create an Xml Stream which can be deserialized into a .Net object. In this instance the XSLT to create the result of a Company Number Search is; <?xml version="1.0" encoding="us-ascii"?> <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform" xmlns:ev="http://www.govtalk.gov.uk/CM/envelope" xmlns:sch="http://xmlgw.companieshouse.gov.uk/v1-0/schema" exclude-result-prefixes="ev"> <xsl:template match="/"> <CompanySearchResult xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"> <CompanyNumber> <xsl:value-of select="ev:GovTalkMessage/ev:Body/sch:NumberSearch/sch:CoSearchItem/sch:CompanyNumber"/> </CompanyNumber> <CompanyName> <xsl:value-of select="ev:GovTalkMessage/ev:Body/sch:NumberSearch/sch:CoSearchItem/sch:CompanyName"/> </CompanyName> </CompanySearchResult> </xsl:template> </xsl:stylesheet> and the object definition is; using System; using System.Collections.Generic; using System.Linq; using System.Web; namespace CompanyHub.Services { public class CompanySearchResult { public CompanySearchResult() { CompanyNumber = String.Empty; CompanyName = String.Empty; } public String CompanyNumber { get; set; } public String CompanyName { get; set; } } } Our entire code to make calls to send a request, and interpret the results are; String request = String.Empty; String response = String.Empty; GovTalkStatus status = null; fault = null; try { using (CompanyNumberSearchRequest requestObj = new CompanyNumberSearchRequest()) { requestObj.PartialCompanyNumber = CompanyNumber; request = Toolbox.CreateRequest(requestObj, "CompanyNumberSearch.xsl"); response = Toolbox.SendGovTalkRequest(request); status = Toolbox.GetMessageStatus(response); if (status.Status.ToLower() == "error") { fault = new HubFault() { Message = status.Text }; } else { Object obj = Toolbox.GetGovTalkResponse(response, "CompanyNumberSearchResult.xsl", typeof(CompanySearchResult)); } } } catch (FaultException<ArgumentException> ex) { fault = new HubFault() { FaultType = ex.Detail.GetType().FullName, Message = ex.Detail.Message }; } catch (System.Exception ex) { fault = new HubFault() { FaultType = ex.GetType().FullName, Message = ex.Message }; } finally { } Wrap up So there we have it – a reusable set of functions to send and interpret XML results from an internet based service. The code is reusable with a little change with any service which uses XML as a transport mechanism – and as for the Companies House GovTalk service all I need to do is create various objects for the result and message sent and the relevent XSLT files. I might need minor changes for other services but something like 70-90% will be exactly the same.

  Read the article

• Confusion related to sigwait in multiprocess system

  - by user34790

  I am having difficulty in understanding IPC in multiprocess system. I have this system where there are three child processes that send two types of signals to their process group. There are four types of signal handling processes responsible for a particular type of signal. There is this monitoring process which waits for both the signals and then processes accordingly. When I run this program for a while, the monitoring process doesn't seem to pick up the signal as well as the signal handling process. I could see in the log that the signal is only being generated but not handled at all. My code is given below #include <cstdlib> #include <iostream> #include <iomanip> #include <unistd.h> #include <sys/types.h> #include <sys/wait.h> #include <sys/time.h> #include <signal.h> #include <unistd.h> #include <fcntl.h> #include <cstdio> #include <stdlib.h> #include <stdio.h> #include <pthread.h> using namespace std; double timestamp() { struct timeval tp; gettimeofday(&tp, NULL); return (double)tp.tv_sec + tp.tv_usec / 1000000.; } double getinterval() { srand(time(NULL)); int r = rand()%10 + 1; double s = (double)r/100; } int count; int count_1; int count_2; double time_1[10]; double time_2[10]; pid_t senders[1]; pid_t handlers[4]; pid_t reporter; void catcher(int sig) { printf("Signal catcher called for %d",sig); } int main(int argc, char *argv[]) { void signal_catcher_int(int); pid_t pid,w; int status; if(signal(SIGUSR1, SIG_IGN) == SIG_ERR) { perror("1"); return 1; } if(signal(SIGUSR2 ,SIG_IGN) == SIG_ERR) { perror("2"); return 2; } if(signal(SIGINT,signal_catcher_int) == SIG_ERR) { perror("3"); return 2; } //Registering the signal handler for(int i=0; i<4; i++) { if((pid = fork()) == 0) { cout << i << endl; //struct sigaction sigact; sigset_t sigset; int sig; int result = 0; sigemptyset(&sigset); if(i%2 == 0) { if(signal(SIGUSR2, SIG_IGN) == SIG_ERR) { perror("2"); return 2; } sigaddset(&sigset, SIGUSR1); sigprocmask(SIG_BLOCK, &sigset, NULL); } else { if(signal(SIGUSR1, SIG_IGN) == SIG_ERR) { perror("2"); return 2; } sigaddset(&sigset, SIGUSR2); sigprocmask(SIG_BLOCK, &sigset, NULL); } while(true) { int result = sigwait(&sigset, &sig); if(result == 0) { cout << "The caught signal is " << sig << endl; } } exit(0); } else { cout << "Registerd the handler " << pid << endl; handlers[i] = pid; } } //Registering the monitoring process if((pid = fork()) == 0) { sigset_t sigset; int sig; int result = 0; sigemptyset(&sigset); sigaddset(&sigset, SIGUSR1); sigaddset(&sigset, SIGUSR2); sigprocmask(SIG_BLOCK, &sigset, NULL); while(true) { int result = sigwait(&sigset, &sig); if(result == 0) { cout << "The monitored signal is " << sig << endl; } else { cout << "error" << endl; } } } else { reporter = pid; } sleep(3); //Registering the signal generator for(int i=0; i<1; i++) { if((pid = fork()) == 0) { if(signal(SIGUSR1, SIG_IGN) == SIG_ERR) { perror("1"); return 1; } if(signal(SIGUSR2, SIG_IGN) == SIG_ERR) { perror("2"); return 2; } srand(time(0)); while(true) { volatile int signal_id = rand()%2 + 1; cout << "Generating the signal " << signal_id << endl; if(signal_id == 1) { killpg(getpgid(getpid()), SIGUSR1); } else { killpg(getpgid(getpid()), SIGUSR2); } int r = rand()%10 + 1; double s = (double)r/100; sleep(s); } exit(0); } else { cout << "Registered the sender " << pid << endl; senders[i] = pid; } } while(w = wait(&status)) { cout << "Wait on PID " << w << endl; } } void signal_catcher_int(int the_sig) { //cout << "Handling the Ctrl C signal " << endl; for(int i=0; i<1; i++) { kill(senders[i],SIGKILL); } for(int i=0; i<4; i++) { kill(handlers[i],SIGKILL); } kill(reporter,SIGKILL); exit(3); } Any suggestions? Here is a sample of the output as well In the beginning Registerd the handler 9544 Registerd the handler 9545 1 Registerd the handler 9546 Registerd the handler 9547 2 3 0 Registered the sender 9550 Generating the signal 1 The caught signal is 10 The monitored signal is 10 The caught signal is 10 Generating the signal 1 The caught signal is 10 The monitored signal is 10 The caught signal is 10 Generating the signal 1 The caught signal is 10 The monitored signal is 10 The caught signal is 10 Generating the signal 1 The caught signal is 10 The monitored signal is 10 The caught signal is 10 Generating the signal 2 The caught signal is 12 The caught signal is 12 The monitored signal is 12 Generating the signal 2 Generating the signal 2 The caught signal is 12 The caught signal is 12 Generating the signal 1 The caught signal is 12 The monitored signal is 10 The monitored signal is 12 Generating the signal 1 Generating the signal 2 The caught signal is 12 Generating the signal 1 Generating the signal 2 10 The monitored signal is 10 The caught signal is 12 Generating the signal 1 The caught signal is 12 The monitored signal is GenThe caught signal is TheThe caught signal is 10 Generating the signal 2 Later on The monitored signal is GenThe monitored signal is 10 Generating the signal 1 Generating the signal 2 The caught signal is 10 The caught signal is 10 The caught signal is 10 The caught signal is 12 Generating the signal 1 Generating the signal 2 Generating the signal 1 Generating the signal 1 Generating the signal 2 Generating the signal 2 Generating the signal 2 Generating the signal 2 Generating the signal 2 Generating the signal 1 The caught signal is 12 The caught signal is 10 The caught signal is 10 Generating the signal 2 Generating the signal 1 Generating the signal 1 Generating the signal 2 Generating the signal 1 Generating the signal 2 Generating the signal 2 Generating the signal 2 Generating the signal 1 Generating the signal 2 Generating the signal 1 Generating the signal 2 Generating the signal 2 The caught signal is 10 Generating the signal 2 Generating the signal 1 Generating the signal 1 As you can see initially, the signal was generated and handled both by my signal handlers and monitoring processes. But later on the signal was generated a lot, but it was not quite processes in the same magnitude as before. Further I could see very less signal processing by the monitoring process Can anyone please provide some insights. What's going on?

  Read the article

• jQuery CSS Property Monitoring Plug-in updated

  - by Rick Strahl

  A few weeks back I had talked about the need to watch properties of an object and be able to take action when certain values changed. The need for this arose out of wanting to build generic components that could 'attach' themselves to other objects. One example is a drop shadow - if I add a shadow behavior to an object I want the shadow to be pinned to that object so when that object moves I also want the shadow to move with it, or when the panel is hidden the shadow should hide with it - automatically without having to explicitly hook up monitoring code to the panel. For example, in my shadow plug-in I can now do something like this (where el is the element that has the shadow attached and sh is the shadow): if (!exists) // if shadow was created el.watch("left,top,width,height,display", function() { if (el.is(":visible")) $(this).shadow(opt); // redraw else sh.hide(); }, 100, "_shadowMove"); The code now monitors several properties and if any of them change the provided function is called. So when the target object is moved or hidden or resized the watcher function is called and the shadow can be redrawn or hidden in the case of visibility going away. So if you run any of the following code: $("#box") .shadow() .draggable({ handle: ".blockheader" }); // drag around the box - shadow should follow // hide the box - shadow should disappear with box setTimeout(function() { $("#box").hide(); }, 4000); // show the box - shadow should come back too setTimeout(function() { $("#box").show(); }, 8000); This can be very handy functionality when you're dealing with objects or operations that you need to track generically and there are no native events for them. For example, with a generic shadow object that attaches itself to any another element there's no way that I know of to track whether the object has been moved or hidden either via some UI operation (like dragging) or via code. While some UI operations like jQuery.ui.draggable would allow events to fire when the mouse is moved nothing of the sort exists if you modify locations in code. Even tracking the object in drag mode this is hardly generic behavior - a generic shadow implementation can't know when dragging is hooked up. So the watcher provides an alternative that basically gives an Observer like pattern that notifies you when something you're interested in changes. In the watcher hookup code (in the shadow() plugin) above  a check is made if the object is visible and if it is the shadow is redrawn. Otherwise the shadow is hidden. The first parameter is a list of CSS properties to be monitored followed by the function that is called. The function called receives this as the element that's been changed and receives two parameters: The array of watched objects with their current values, plus an index to the object that caused the change function to fire. How does it work When I wrote it about this last time I started out with a simple timer that would poll for changes at a fixed interval with setInterval(). A few folks commented that there are is a DOM API - DOMAttrmodified in Mozilla and propertychange in IE that allow notification whenever any property changes which is much more efficient and smooth than the setInterval approach I used previously. On browser that support these events (FireFox and IE basically - WebKit has the DOMAttrModified event but it doesn't appear to work) the shadow effect is instant - no 'drag behind' of the shadow. Running on a browser that doesn't support still uses setInterval() and the shadow movement is slightly delayed which looks sloppy. There are a few additional changes to this code - it also supports monitoring multiple CSS properties now so a single object can monitor a host of CSS properties rather than one object per property which is easier to work with. For display purposes position, bounds and visibility will be common properties that are to be watched. Here's what the new version looks like: $.fn.watch = function (props, func, interval, id) { /// <summary> /// Allows you to monitor changes in a specific /// CSS property of an element by polling the value. /// when the value changes a function is called. /// The function called is called in the context /// of the selected element (ie. this) /// </summary> /// <param name="prop" type="String">CSS Properties to watch sep. by commas</param> /// <param name="func" type="Function"> /// Function called when the value has changed. /// </param> /// <param name="interval" type="Number"> /// Optional interval for browsers that don't support DOMAttrModified or propertychange events. /// Determines the interval used for setInterval calls. /// </param> /// <param name="id" type="String">A unique ID that identifies this watch instance on this element</param> /// <returns type="jQuery" /> if (!interval) interval = 200; if (!id) id = "_watcher"; return this.each(function () { var _t = this; var el$ = $(this); var fnc = function () { __watcher.call(_t, id) }; var itId = null; var data = { id: id, props: props.split(","), func: func, vals: [props.split(",").length], fnc: fnc, origProps: props, interval: interval }; $.each(data.props, function (i) { data.vals[i] = el$.css(data.props[i]); }); el$.data(id, data); hookChange(el$, id, data.fnc); }); function hookChange(el$, id, fnc) { el$.each(function () { var el = $(this); if (typeof (el.get(0).onpropertychange) == "object") el.bind("propertychange." + id, fnc); else if ($.browser.mozilla) el.bind("DOMAttrModified." + id, fnc); else itId = setInterval(fnc, interval); }); } function __watcher(id) { var el$ = $(this); var w = el$.data(id); if (!w) return; var _t = this; if (!w.func) return; // must unbind or else unwanted recursion may occur el$.unwatch(id); var changed = false; var i = 0; for (i; i < w.props.length; i++) { var newVal = el$.css(w.props[i]); if (w.vals[i] != newVal) { w.vals[i] = newVal; changed = true; break; } } if (changed) w.func.call(_t, w, i); // rebind event hookChange(el$, id, w.fnc); } } $.fn.unwatch = function (id) { this.each(function () { var el = $(this); var fnc = el.data(id).fnc; try { if (typeof (this.onpropertychange) == "object") el.unbind("propertychange." + id, fnc); else if ($.browser.mozilla) el.unbind("DOMAttrModified." + id, fnc); else clearInterval(id); } // ignore if element was already unbound catch (e) { } }); return this; } There are basically two jQuery functions - watch and unwatch. jQuery.fn.watch(props,func,interval,id) Starts watching an element for changes in the properties specified. props The CSS properties that are to be watched for changes. If any of the specified properties changes the function specified in the second parameter is fired. func (watchData,index) The function fired in response to a changed property. Receives this as the element changed and object that represents the watched properties and their respective values. The first parameter is passed in this structure:    { id: itId, props: [], func: func, vals: [] }; A second parameter is the index of the changed property so data.props[i] or data.vals[i] gets the property value that has changed. interval The interval for setInterval() for those browsers that don't support property watching in the DOM. In milliseconds. id An optional id that identifies this watcher. Required only if multiple watchers might be hooked up to the same element. The default is _watcher if not specified. jQuery.fn.unwatch(id) Unhooks watching of the element by disconnecting the event handlers. id Optional watcher id that was specified in the call to watch. This value can be omitted to use the default value of _watcher. You can also grab the latest version of the  code for this plug-in as well as the shadow in the full library at: http://www.west-wind.com:8080/svn/jquery/trunk/jQueryControls/Resources/ww.jquery.js watcher has no other dependencies although it lives in this larger library. The shadow plug-in depends on watcher.© Rick Strahl, West Wind Technologies, 2005-2011

  Read the article

• Restricting joystick within a radius of center

  - by Phil

  I'm using Unity3d iOs and am using the example joysticks that came with one of the packages. It works fine but the area the joystick moves in is a rectangle which is unintuitive for my type of game. I can figure out how to see if the distance between the center and the current point is too far but I can't figure out how to constrain it to a certain distance without interrupting the finger tracking. Here's the relevant code: using UnityEngine; using System.Collections; public class Boundary { public Vector2 min = Vector2.zero; public Vector2 max = Vector2.zero; } public class Joystick : MonoBehaviour{ static private Joystick[] joysticks; // A static collection of all joysticks static private bool enumeratedJoysticks=false; static private float tapTimeDelta = 0.3f; // Time allowed between taps public bool touchPad; // Is this a TouchPad? public Rect touchZone; public Vector2 deadZone = Vector2.zero; // Control when position is output public bool normalize = false; // Normalize output after the dead-zone? public Vector2 position; // [-1, 1] in x,y public int tapCount; // Current tap count private int lastFingerId = -1; // Finger last used for this joystick private float tapTimeWindow; // How much time there is left for a tap to occur private Vector2 fingerDownPos; private float fingerDownTime; private float firstDeltaTime = 0.5f; private GUITexture gui; // Joystick graphic private Rect defaultRect; // Default position / extents of the joystick graphic private Boundary guiBoundary = new Boundary(); // Boundary for joystick graphic public Vector2 guiTouchOffset; // Offset to apply to touch input private Vector2 guiCenter; // Center of joystick private Vector3 tmpv3; private Rect tmprect; private Color tmpclr; public float allowedDistance; public enum JoystickType { movement, rotation } public JoystickType joystickType; public void Start() { // Cache this component at startup instead of looking up every frame gui = (GUITexture) GetComponent( typeof(GUITexture) ); // Store the default rect for the gui, so we can snap back to it defaultRect = gui.pixelInset; if ( touchPad ) { // If a texture has been assigned, then use the rect ferom the gui as our touchZone if ( gui.texture ) touchZone = gui.pixelInset; } else { // This is an offset for touch input to match with the top left // corner of the GUI guiTouchOffset.x = defaultRect.width * 0.5f; guiTouchOffset.y = defaultRect.height * 0.5f; // Cache the center of the GUI, since it doesn't change guiCenter.x = defaultRect.x + guiTouchOffset.x; guiCenter.y = defaultRect.y + guiTouchOffset.y; // Let's build the GUI boundary, so we can clamp joystick movement guiBoundary.min.x = defaultRect.x - guiTouchOffset.x; guiBoundary.max.x = defaultRect.x + guiTouchOffset.x; guiBoundary.min.y = defaultRect.y - guiTouchOffset.y; guiBoundary.max.y = defaultRect.y + guiTouchOffset.y; } } public void Disable() { gameObject.active = false; enumeratedJoysticks = false; } public void ResetJoystick() { if (joystickType != JoystickType.rotation) { //Don't do anything if turret mode // Release the finger control and set the joystick back to the default position gui.pixelInset = defaultRect; lastFingerId = -1; position = Vector2.zero; fingerDownPos = Vector2.zero; if ( touchPad ){ tmpclr = gui.color; tmpclr.a = 0.025f; gui.color = tmpclr; } } else { //gui.pixelInset = defaultRect; lastFingerId = -1; position = position; fingerDownPos = fingerDownPos; if ( touchPad ){ tmpclr = gui.color; tmpclr.a = 0.025f; gui.color = tmpclr; } } } public bool IsFingerDown() { return (lastFingerId != -1); } public void LatchedFinger( int fingerId ) { // If another joystick has latched this finger, then we must release it if ( lastFingerId == fingerId ) ResetJoystick(); } public void Update() { if ( !enumeratedJoysticks ) { // Collect all joysticks in the game, so we can relay finger latching messages joysticks = (Joystick[]) FindObjectsOfType( typeof(Joystick) ); enumeratedJoysticks = true; } //CHeck if distance is over the allowed amount //Get centerPosition //Get current position //Get distance //If over, don't allow int count = iPhoneInput.touchCount; // Adjust the tap time window while it still available if ( tapTimeWindow > 0 ) tapTimeWindow -= Time.deltaTime; else tapCount = 0; if ( count == 0 ) ResetJoystick(); else { for(int i = 0;i < count; i++) { iPhoneTouch touch = iPhoneInput.GetTouch(i); Vector2 guiTouchPos = touch.position - guiTouchOffset; bool shouldLatchFinger = false; if ( touchPad ) { if ( touchZone.Contains( touch.position ) ) shouldLatchFinger = true; } else if ( gui.HitTest( touch.position ) ) { shouldLatchFinger = true; } // Latch the finger if this is a new touch if ( shouldLatchFinger && ( lastFingerId == -1 || lastFingerId != touch.fingerId ) ) { if ( touchPad ) { tmpclr = gui.color; tmpclr.a = 0.15f; gui.color = tmpclr; lastFingerId = touch.fingerId; fingerDownPos = touch.position; fingerDownTime = Time.time; } lastFingerId = touch.fingerId; // Accumulate taps if it is within the time window if ( tapTimeWindow > 0 ) { tapCount++; print("tap" + tapCount.ToString()); } else { tapCount = 1; print("tap" + tapCount.ToString()); //Tell gameobject that player has tapped turret joystick if (joystickType == JoystickType.rotation) { //TODO: Call! } tapTimeWindow = tapTimeDelta; } // Tell other joysticks we've latched this finger foreach ( Joystick j in joysticks ) { if ( j != this ) j.LatchedFinger( touch.fingerId ); } } if ( lastFingerId == touch.fingerId ) { // Override the tap count with what the iPhone SDK reports if it is greater // This is a workaround, since the iPhone SDK does not currently track taps // for multiple touches if ( touch.tapCount > tapCount ) tapCount = touch.tapCount; if ( touchPad ) { // For a touchpad, let's just set the position directly based on distance from initial touchdown position.x = Mathf.Clamp( ( touch.position.x - fingerDownPos.x ) / ( touchZone.width / 2 ), -1, 1 ); position.y = Mathf.Clamp( ( touch.position.y - fingerDownPos.y ) / ( touchZone.height / 2 ), -1, 1 ); } else { // Change the location of the joystick graphic to match where the touch is tmprect = gui.pixelInset; tmprect.x = Mathf.Clamp( guiTouchPos.x, guiBoundary.min.x, guiBoundary.max.x ); tmprect.y = Mathf.Clamp( guiTouchPos.y, guiBoundary.min.y, guiBoundary.max.y ); //Check distance float distance = Vector2.Distance(new Vector2(defaultRect.x, defaultRect.y), new Vector2(tmprect.x, tmprect.y)); float angle = Vector2.Angle(new Vector2(defaultRect.x, defaultRect.y), new Vector2(tmprect.x, tmprect.y)); if (distance < allowedDistance) { //Ok gui.pixelInset = tmprect; } else { //This is where I don't know what to do... } } if ( touch.phase == iPhoneTouchPhase.Ended || touch.phase == iPhoneTouchPhase.Canceled ) ResetJoystick(); } } } if ( !touchPad ) { // Get a value between -1 and 1 based on the joystick graphic location position.x = ( gui.pixelInset.x + guiTouchOffset.x - guiCenter.x ) / guiTouchOffset.x; position.y = ( gui.pixelInset.y + guiTouchOffset.y - guiCenter.y ) / guiTouchOffset.y; } // Adjust for dead zone float absoluteX = Mathf.Abs( position.x ); float absoluteY = Mathf.Abs( position.y ); if ( absoluteX < deadZone.x ) { // Report the joystick as being at the center if it is within the dead zone position.x = 0; } else if ( normalize ) { // Rescale the output after taking the dead zone into account position.x = Mathf.Sign( position.x ) * ( absoluteX - deadZone.x ) / ( 1 - deadZone.x ); } if ( absoluteY < deadZone.y ) { // Report the joystick as being at the center if it is within the dead zone position.y = 0; } else if ( normalize ) { // Rescale the output after taking the dead zone into account position.y = Mathf.Sign( position.y ) * ( absoluteY - deadZone.y ) / ( 1 - deadZone.y ); } } } So the later portion of the code handles the updated position of the joystick thumb. This is where I'd like it to track the finger position in a direction it still is allowed to move (like if the finger is too far up and slightly to the +X I'd like to make sure the joystick is as close in X and Y as allowed within the radius) Thanks for reading!

  Read the article

• BizTalk: History of one project architecture

  - by Leonid Ganeline

  "In the beginning God made heaven and earth. Then he started to integrate." At the very start was the requirement: integrate two working systems. Small digging up: It was one system. It was good but IT guys want to change it to the new one, much better, chipper, more flexible, and more progressive in technologies, more suitable for the future, for the faster world and hungry competitors. One thing. One small, little thing. We cannot turn off the old system (call it A, because it was the first), turn on the new one (call it B, because it is second but not the last one). The A has a hundreds users all across a country, they must study B. A still has a lot nice custom features, home-made features that cannot disappear. These features have to be moved to the B and it is a long process, months and months of redevelopment. So, the decision was simple. Let’s move not jump, let’s both systems working side-by-side several months. In this time we could teach the users and move all custom A’s special functionality to B. That automatically means both systems should work side-by-side all these months and use the same data. Data in A and B must be in sync. That’s how the integration projects get birth. Moreover, the specific of the user tasks requires the both systems must be in sync in real-time. Nightly synchronization is not working, absolutely.   First draft The first draft seems simple. Both systems keep data in SQL databases. When data changes, the Create, Update, Delete operations performed on the data, and the sync process could be started. The obvious decision is to use triggers on tables. When we are talking about data, we are talking about several entities. For example, Orders and Items [in Orders]. We decided to use the BizTalk Server to synchronize systems. Why it was chosen is another story. Second draft   Let’s take an example how it works in more details. 1.       User creates a new entity in the A system. This fires an insert trigger on the entity table. Trigger has to pass the message “Entity created”. This message includes all attributes of the new entity, but I focused on the Id of this entity in the A system. Notation for this message is id.A. System A sends id.A to the BizTalk Server. 2.       BizTalk transforms id.A to the format of the system B. This is easiest part and I will not focus on this kind of transformations in the following text. The message on the picture is still id.A but it is in slightly different format, that’s why it is changing in color. BizTalk sends id.A to the system B. 3.       The system B creates the entity on its side. But it uses different id-s for entities, these id-s are id.B. System B saves id.A+id.B. System B sends the message id.A+id.B back to the BizTalk. 4.       BizTalk sends the message id.A+id.B to the system A. 5.       System A saves id.A+id.B. Why both id-s should be saved on both systems? It was one of the next requirements. Users of both systems have to know the systems are in sync or not in sync. Users working with the entity on the system A can see the id.B and use it to switch to the system B and work there with the copy of the same entity. The decision was to store the pairs of entity id-s on both sides. If there is only one id, the entities are not in sync yet (for the Create operation). Third draft Next problem was the reliability of the synchronization. The synchronizing process can be interrupted on each step, when message goes through the wires. It can be communication problem, timeout, temporary shutdown one of the systems, the second system cannot be synchronized by some internal reason. There were several potential problems that prevented from enclosing the whole synchronization process in one transaction. Decision was to restart the whole sync process if it was not finished (in case of the error). For this purpose was created an additional service. Let’s call it the Resync service. We still keep the id pairs in both systems, but only for the fast access not for the synchronization process. For the synchronizing these id-s now are kept in one main place, in the Resync service database. The Resync service keeps record as: ·       Id.A ·       Id.B ·       Entity.Type ·       Operation (Create, Update, Delete) ·       IsSyncStarted (true/false) ·       IsSyncFinished (true/false0 The example now looks like: 1.       System A creates id.A. id.A is saved on the A. Id.A is sent to the BizTalk. 2.       BizTalk sends id.A to the Resync and to the B. id.A is saved on the Resync. 3.       System B creates id.B. id.A+id.B are saved on the B. id.A+id.B are sent to the BizTalk. 4.       BizTalk sends id.A+id.B to the Resync and to the A. id.A+id.B are saved on the Resync. 5.       id.A+id.B are saved on the B. Resync changes the IsSyncStarted and IsSyncFinished flags accordingly. The Resync service implements three main methods: ·       Save (id.A, Entity.Type, Operation) ·       Save (id.A, id.B, Entity.Type, Operation) ·       Resync () Two Save() are used to save id-s to the service storage. See in the above example, in 2 and 4 steps. What about the Resync()? It is the method that finishes the interrupted synchronization processes. If Save() is started by the trigger event, the Resync() is working as an independent process. It periodically scans the Resync storage to find out “unfinished” records. Then it restarts the synchronization processes. It tries to synchronize them several times then gives up.     One more thing, both systems A and B must tolerate duplicates of one synchronizing process. Say on the step 3 the system B was not able to send id.A+id.B back. The Resync service must restart the synchronization process that will send the id.A to B second time. In this case system B must just send back again also created id.A+id.B pair without errors. That means “tolerate duplicates”. Fourth draft Next draft was created only because of the aesthetics. As it always happens, aesthetics gave significant performance gain to the whole system. First was the stupid question. Why do we need this additional service with special database? Can we just master the BizTalk to do something like this Resync() does? So the Resync orchestration is doing the same thing as the Resync service. It is started by the Id.A and finished by the id.A+id.B message. The first works as a Start message, the second works as a Finish message.     Here is a diagram the whole process without errors. It is pretty straightforward. The Resync orchestration is waiting for the Finish message specific period of time then resubmits the Id.A message. It resubmits the Id.A message specific number of times then gives up and gets suspended. It can be resubmitted then it starts the whole process again: waiting [, resubmitting [, get suspended]], finishing. Tuning up The Resync orchestration resubmits the id.A message with special “Resubmitted” flag. The subscription filter on the Resync orchestration includes predicate as (Resubmit_Flag != “Resubmitted”). That means only the first Sync orchestration starts the Resync orchestration. Other Sync orchestration instantiated by the resubmitting can finish this Resync orchestration but cannot start another instance of the Resync   Here is a diagram where system B was inaccessible for some period of time. The Resync orchestration resubmitted the id.A two times. Then system B got the response the id.A+id.B and this finished the Resync service execution. What is interesting about this, there were submitted several identical id.A messages and only one id.A+id.B message. Because of this, the system B and the Resync must tolerate the duplicate messages. We also told about this requirement for the system B. Now the same requirement is for the Resunc. Let’s assume the system B was very slow in the first response and the Resync service had time to resubmit two id.A messages. System B responded not, as it was in previous case, with one id.A+id.B but with two id.A+id.B messages. First of them finished the Resync execution for the id.A. What about the second id.A+id.B? Where it goes? So, we have to add one more internal requirement. The whole solution must tolerate many identical id.A+id.B messages. It is easy task with the BizTalk. I added the “SinkExtraMessages” subscriber (orchestration with one receive shape), that just get these messages and do nothing. Real design Real architecture is much more complex and interesting. In reality each system can submit several id.A almost simultaneously and completely unordered. There are not only the “Create entity” operation but the Update and Delete operations. And these operations relate each other. Say the Update operation after Delete means not the same as Update after Create. In reality there are entities related each other. Say the Order and Order Items. Change on one of it could start the series of the operations on another. Moreover, the system internals are the “black boxes” and we cannot predict the exact content and order of the operation series. It worth to say, I had to spend a time to manage the zombie message problems. The zombies are still here, but this is not a problem now. And this is another story. What is interesting in the last design? One orchestration works to help another to be more reliable. Why two orchestration design is more reliable, isn’t it something strange? The Synch orchestration takes all the message exchange between systems, here is the area where most of the errors could happen. The Resync orchestration sends and receives messages only within the BizTalk server. Is there another design? Sure. All Resync functionality could be implemented inside the Sync orchestration. Hey guys, some other ideas?

  Read the article

• The Internet of Things & Commerce: Part 3 -- Interview with Kristen J. Flanagan, Commerce Product Management

  - by Katrina Gosek, Director | Commerce Product Strategy-Oracle

  Internet of Things & Commerce Series: Part 3 (of 3) And now for the final installment my three part series on the Internet of Things & Commerce. Post one, “The Next 7,000 Days”, introduced the idea of the Internet of Things, followed by a second post interviewing one of our chief commerce innovation strategists, Brian Celenza.  This final post in the series is an interview with Kristen J. Flanagan, lead product manager for Oracle Commerce omnichannel strategy. She takes us through the past, present, and future of how our Commerce Solution is re-imagining the way physical and digital shopping come together. ------- QUESTION: It’s your job to stay on top of what our customers’ need to not only run their online businesses effectively, but also to make sure they have product capabilities they can innovate and grow on. What key trend has been top-of-mind for you and our customers around this collision of physical and digital shopping? Kristen: I’ll agree with Brian Celenza that hands down mobile has forced a major disruption in shopping and selling behavior. A few years ago, mobile exploded at a pace I don't think anyone was expecting. Early on, we saw our customers scrambling to establish a mobile presence---mostly through "screen scraping" technologies. As smartphones continued to advance (at lightening speed!), our customers started to investigate ways to truly tap in to their eCommerce capabilities to deliver the mobile experience. They started looking to us for a means of using the eCommerce services and capabilities to deliver a mobile experience that is tailored for mobile rather than the desktop experience on a smaller screen. In the future, I think we'll see customers starting to really understand what their shoppers need and expect from a mobile offering and how they can adapt their content and delivery of that content to meet those needs. And, mobile shopping doesn’t stop at the consumer / buyer. Because the in-store experience is compelling and has advantages that digital just can't offer, we're also starting to see the eCommerce services being leveraged for mobile for in-store sales associates. Brick-and-mortar retailers are interested in putting the omnichannel product catalog, promotions, and cart into the hands of knowledgeable associates. Retailers are now looking to connect and harness the eCommerce data in-store so that shoppers have a reason to walk-in. I think we'll be seeing a lot more customers thinking about melding the in-store and digital experiences to present a richer offering for shoppers.    QUESTION: What are some examples of what our customers are doing currently to bring these concepts to reality? Kristen: Well, without question, connecting digital and brick-and-mortar worlds is becoming tablestakes for selling experiences. If a brand has a foot in both worlds (i.e., isn’t a pureplay online retailer), they have to connect the dots because shoppers – whether consumers or B2B buyers –don't think in clearly defined channels anymore. The expectation is connectedness – for on- and offline experiences, promotions, products, and customer data. What does this mean practically for businesses selling goods on- and offline? It touches a lot of systems: inventory info on the eCommerce site, fulfillment options across channels (buy online/pickup in store), order information (representing various channels for a cohesive view of shopper order history), promotions across digital and store, etc.  A few years ago, the main link between store and digital was the smartphone. We all remember when “apps” became a thing and many of our customers were scrambling to get a native app out there. Now we're seeing more strategic thinking around the benefits of mobile web vs. native and how that ties in to the purpose and role of mobile within the digital channel. Put it more broadly, how these pieces fit together in the overall brand puzzle.  The same could be said for “showrooming.” Where it was a major concern (i.e., shoppers using stores to look at merchandise and then order online from Amazon), in recent months, it’s emerged that the inverse is now becoming a a reality as well. "Webrooming" (using digital sites to do research before making a purchase in the store) is a new behavior pure play retailers are challenged with. There are many technologies, behaviors, and information that need to tie together to offer a holistic omnichannel shopping experience. As a result, brands are looking for ways to connect the digital and in-store experiences to bridge the gaps: shared assortments across channels, assisted selling apps that arm associates with information about shoppers, shared promotions, inventory, etc. QUESTION: How has Oracle Commerce been built to help brands make the link between in-store and digital over the last few years? Kristen: Over the last seven years, the product has been in step with the changes in industry needs. Here is a brief history of the evolution: Prior to Oracle’s acquisition of ATG and Endeca, key investments were made to cross-channel functionality that we are still building on today. Commerce Service Center (v2007.1) ATG introduced the Commerce Service Center in 2007.1 and marked the first entry into what was then called “cross-channel.” The Commerce Service Center is a call-center-agent-facing application that enables agents to see shopper orders, online catalog, promotions, and pricing. It is tightly integrated with the eCommerce capabilities of the platform and commerce engine and provided a means of connecting data from the call center and online channels.  REST services framework (v9.1)  In v9.1 we introduced the REST services framework and interface in the Platform that enabled customers to use ATG web services in other applications. This framework has become the basis for our subsequent omni-channel features and functionality. Multisite Architecture (v10) With the v10 release, we introduced the Multisite Architecture, which enabled customers to manage multiple sites (and channels) within a single instance of the BCC. Customers could create site- and channel-specific catalogs, promotions, targeters, and scenarios. Endeca Page Builder (2.x) / Experience Manager (3.x) With the introduction of Endeca for Mobile (now part of the core platform, available through the reference store – see blow) on top of Page Builder (and then eventually Experience Manager), Endeca gave business users the tools to create and manage native and mobile web applications. And since the acquisition of both ATG (2011) and Endeca (2012), Oracle Commerce has leveraged the best of each leading technology’s capabilities for omnichannel commerce to continue to drive innovation for our customers. Service enablement of core Oracle Commerce capabilities (v10.1.1, 10.2, & 11) After the establishment of the REST services framework and interface, we followed up in subsequent releases with service enablement of core Oracle Commerce capabilities throughout the iOS native app and the enablement of the core Commerce Service Center features. The result is that customers can leverage these services for their integrations with other systems, as well as their omnichannel initiatives.  Mobile web reference application (v10.1) In 10.1 we introduced the shopper-facing mobile reference application that showed how to use Oracle Commerce to deliver a mobile web experience for shoppers. This included the use of Experience Manager and cartridges to drive those experiences on select pages.  Native (iOS) reference application (v10.1.1)  We came out with the 10.1.1 shopper-facing native iOS ref app that illustrated how to use the Commerce REST services to deliver an iOS app. Also included Experience Manager-driven pages.   Assisted Selling reference application (v10.2.1)  The Assisted Selling reference application is our first reference application designed for the in-store associate. This iOS app shows customers how they can use Oracle Commerce data and information to provide a high-touch, consultative sales environment as well as to put the endless aisle into hands of their associates. Shoppers can start a cart online, and in-store associates can access that cart via the application to provide more information or add products and then transact using the ATG engine. Support for Retail promotions (v11) As part of the v11 release, we worked with teams in the Oracle Retail Global Business Unit (RGBU) to assess which promotion types and capabilities are supported across our products. Those products included Oracle Commerce, Oracle Point of Service (ORPOS), and Oracle Retail Price Management (RPM). The result is that customers can now more easily support omnichannel use cases between the store and digital.  Making sure Oracle Commerce can help support the omnichannel needs of our customers is core to our product strategy. With 89% of consumers now use two or more channels to make a single purchase, ensuring that cross-channel interactions are linked is critical to a great customer experience – and to sales. As Oracle Commerce evolves, we want to make it simple for organizations to create, deliver, and scale experiences across touchpoints with our create once, deploy commerce anywhere framework. We have a flexible, services-oriented architecture that allows data, content, catalogs, cart, experiences, personalization, and merchandising to be shared across touchpoints and easily extended in to new environments like mobile, social, in-store, Call Center, and new Websites. [For the latest downloads and Oracle Commerce documentation, please visit the Oracle Technical Network.] ------ Thank you to both Brian and Kristen for their contributions and to this blog series and their continued thought leadership for Oracle Commerce. We are all looking forward to the coming years of months of new shopping behaviors and opportunities to innovate. Because – if the digital fabric of our everyday lives continues to change at the same pace – the next five years (that just under 2,000 days), will be dramatic. ---------- THIS DOCUMENT IS FOR INFORMATIONAL PURPOSES ONLY AND MAY NOT BE INCORPORATED INTO A CONTRACT OR AGREEMENT

  Read the article

• Solving Big Problems with Oracle R Enterprise, Part II

  - by dbayard

  Part II – Solving Big Problems with Oracle R Enterprise In the first post in this series (see https://blogs.oracle.com/R/entry/solving_big_problems_with_oracle), we showed how you can use R to perform historical rate of return calculations against investment data sourced from a spreadsheet.  We demonstrated the calculations against sample data for a small set of accounts.  While this worked fine, in the real-world the problem is much bigger because the amount of data is much bigger.  So much bigger that our approach in the previous post won’t scale to meet the real-world needs. From our previous post, here are the challenges we need to conquer: The actual data that needs to be used lives in a database, not in a spreadsheet The actual data is much, much bigger- too big to fit into the normal R memory space and too big to want to move across the network The overall process needs to run fast- much faster than a single processor The actual data needs to be kept secured- another reason to not want to move it from the database and across the network And the process of calculating the IRR needs to be integrated together with other database ETL activities, so that IRR’s can be calculated as part of the data warehouse refresh processes In this post, we will show how we moved from sample data environment to working with full-scale data.  This post is based on actual work we did for a financial services customer during a recent proof-of-concept. Getting started with the Database At this point, we have some sample data and our IRR function.  We were at a similar point in our customer proof-of-concept exercise- we had sample data but we did not have the full customer data yet.  So our database was empty.  But, this was easily rectified by leveraging the transparency features of Oracle R Enterprise (see https://blogs.oracle.com/R/entry/analyzing_big_data_using_the).  The following code shows how we took our sample data SimpleMWRRData and easily turned it into a new Oracle database table called IRR_DATA via ore.create().  The code also shows how we can access the database table IRR_DATA as if it was a normal R data.frame named IRR_DATA. If we go to sql*plus, we can also check out our new IRR_DATA table: At this point, we now have our sample data loaded in the database as a normal Oracle table called IRR_DATA.  So, we now proceeded to test our R function working with database data. As our first test, we retrieved the data from a single account from the IRR_DATA table, pull it into local R memory, then call our IRR function.  This worked.  No SQL coding required! Going from Crawling to Walking Now that we have shown using our R code with database-resident data for a single account, we wanted to experiment with doing this for multiple accounts.  In other words, we wanted to implement the split-apply-combine technique we discussed in our first post in this series.  Fortunately, Oracle R Enterprise provides a very scalable way to do this with a function called ore.groupApply().  You can read more about ore.groupApply() here: https://blogs.oracle.com/R/entry/analyzing_big_data_using_the1 Here is an example of how we ask ORE to take our IRR_DATA table in the database, split it by the ACCOUNT column, apply a function that calls our SimpleMWRR() calculation, and then combine the results. (If you are following along at home, be sure to have installed our myIRR package on your database server via  “R CMD INSTALL myIRR”). The interesting thing about ore.groupApply is that the calculation is not actually performed in my desktop R environment from which I am running.  What actually happens is that ore.groupApply uses the Oracle database to perform the work.  And the Oracle database is what actually splits the IRR_DATA table by ACCOUNT.  Then the Oracle database takes the data for each account and sends it to an embedded R engine running on the database server to apply our R function.  Then the Oracle database combines all the individual results from the calls to the R function. This is significant because now the embedded R engine only needs to deal with the data for a single account at a time.  Regardless of whether we have 20 accounts or 1 million accounts or more, the R engine that performs the calculation does not care.  Given that normal R has a finite amount of memory to hold data, the ore.groupApply approach overcomes the R memory scalability problem since we only need to fit the data from a single account in R memory (not all of the data for all of the accounts). Additionally, the IRR_DATA does not need to be sent from the database to my desktop R program.  Even though I am invoking ore.groupApply from my desktop R program, because the actual SimpleMWRR calculation is run by the embedded R engine on the database server, the IRR_DATA does not need to leave the database server- this is both a performance benefit because network transmission of large amounts of data take time and a security benefit because it is harder to protect private data once you start shipping around your intranet. Another benefit, which we will discuss in a few paragraphs, is the ability to leverage Oracle database parallelism to run these calculations for dozens of accounts at once. From Walking to Running ore.groupApply is rather nice, but it still has the drawback that I run this from a desktop R instance.  This is not ideal for integrating into typical operational processes like nightly data warehouse refreshes or monthly statement generation.  But, this is not an issue for ORE.  Oracle R Enterprise lets us run this from the database using regular SQL, which is easily integrated into standard operations.  That is extremely exciting and the way we actually did these calculations in the customer proof. As part of Oracle R Enterprise, it provides a SQL equivalent to ore.groupApply which it refers to as “rqGroupEval”.  To use rqGroupEval via SQL, there is a bit of simple setup needed.  Basically, the Oracle Database needs to know the structure of the input table and the grouping column, which we are able to define using the database’s pipeline table function mechanisms. Here is the setup script: At this point, our initial setup of rqGroupEval is done for the IRR_DATA table.  The next step is to define our R function to the database.  We do that via a call to ORE’s rqScriptCreate. Now we can test it.  The SQL you use to run rqGroupEval uses the Oracle database pipeline table function syntax.  The first argument to irr_dataGroupEval is a cursor defining our input.  You can add additional where clauses and subqueries to this cursor as appropriate.  The second argument is any additional inputs to the R function.  The third argument is the text of a dummy select statement.  The dummy select statement is used by the database to identify the columns and datatypes to expect the R function to return.  The fourth argument is the column of the input table to split/group by.  The final argument is the name of the R function as you defined it when you called rqScriptCreate(). The Real-World Results In our real customer proof-of-concept, we had more sophisticated calculation requirements than shown in this simplified blog example.  For instance, we had to perform the rate of return calculations for 5 separate time periods, so the R code was enhanced to do so.  In addition, some accounts needed a time-weighted rate of return to be calculated, so we extended our approach and added an R function to do that.  And finally, there were also a few more real-world data irregularities that we needed to account for, so we added logic to our R functions to deal with those exceptions.  For the full-scale customer test, we loaded the customer data onto a Half-Rack Exadata X2-2 Database Machine.  As our half-rack had 48 physical cores (and 96 threads if you consider hyperthreading), we wanted to take advantage of that CPU horsepower to speed up our calculations.  To do so with ORE, it is as simple as leveraging the Oracle Database Parallel Query features.  Let’s look at the SQL used in the customer proof: Notice that we use a parallel hint on the cursor that is the input to our rqGroupEval function.  That is all we need to do to enable Oracle to use parallel R engines. Here are a few screenshots of what this SQL looked like in the Real-Time SQL Monitor when we ran this during the proof of concept (hint: you might need to right-click on these images to be able to view the images full-screen to see the entire image): From the above, you can notice a few things (numbers 1 thru 5 below correspond with highlighted numbers on the images above.  You may need to right click on the above images and view the images full-screen to see the entire image): The SQL completed in 110 seconds (1.8minutes) We calculated rate of returns for 5 time periods for each of 911k accounts (the number of actual rows returned by the IRRSTAGEGROUPEVAL operation) We accessed 103m rows of detailed cash flow/market value data (the number of actual rows returned by the IRR_STAGE2 operation) We ran with 72 degrees of parallelism spread across 4 database servers Most of our 110seconds was spent in the “External Procedure call” event On average, we performed 8,200 executions of our R function per second (110s/911k accounts) On average, each execution was passed 110 rows of data (103m detail rows/911k accounts) On average, we did 41,000 single time period rate of return calculations per second (each of the 8,200 executions of our R function did rate of return calculations for 5 time periods) On average, we processed over 900,000 rows of database data in R per second (103m detail rows/110s) R + Oracle R Enterprise: Best of R + Best of Oracle Database This blog post series started by describing a real customer problem: how to perform a lot of calculations on a lot of data in a short period of time.  While standard R proved to be a very good fit for writing the necessary calculations, the challenge of working with a lot of data in a short period of time remained. This blog post series showed how Oracle R Enterprise enables R to be used in conjunction with the Oracle Database to overcome the data volume and performance issues (as well as simplifying the operations and security issues).  It also showed that we could calculate 5 time periods of rate of returns for almost a million individual accounts in less than 2 minutes. In a future post, we will take the same R function and show how Oracle R Connector for Hadoop can be used in the Hadoop world.  In that next post, instead of having our data in an Oracle database, our data will live in Hadoop and we will how to use the Oracle R Connector for Hadoop and other Oracle Big Data Connectors to move data between Hadoop, R, and the Oracle Database easily.

  Read the article

• Using SPServices &amp; jQuery to Find My Stuff from Multi-Select Person/Group Field

  - by Mark Rackley

  Okay… quick blog post for all you SPServices fans out there. I needed to quickly write a script that would return all the tasks currently assigned to me.  I also wanted it to return any task that was assigned to a group I belong to. This can actually be done with a CAML query, so no big deal, right?  The rub is that the “assigned to” field is a multi-select person or group field. As far as I know (and I actually know so little) you cannot just write a CAML query to return this information. If you can, please leave a comment below and disregard the rest of this blog post… So… what’s a hacker to do? As always, I break things down to their most simple components (I really love the KISS principle and would get it tattooed on my back if people wouldn’t think it meant “Knights In Satan’s Service”. You really gotta be an old far to get that reference).  Here’s what we’re going to do: Get currently logged in user’s name as it is stored in a person field Find all the SharePoint groups the current user belongs to Retrieve a set of assigned tasks from the task list and then find those that are assigned to current  user or group current user belongs to Nothing too hairy… So let’s get started Some Caveats before I continue There are some obvious performance implications with this solution as I make a total of four SPServices calls and there’s a lot of looping going on. Also, the CAML query in this blog has NOT been optimized. If you move forward with this code, tweak it so that it returns a further subset of data or you will see horrible performance if you have a few hundred entries in your task list. Add a date range to the CAML or something. Find some way to limit the results as much as possible. Lastly, if you DO have a better solution, I would like you to share. Iron sharpens iron and all…   Alright, let’s really get started. Get currently logged in user’s name as it is stored in a person field First thing we need to do is understand how a person group looks when you look at the XML returned from a SharePoint Web Service call. It turns out it’s stored like any other multi select item in SharePoint which is <id>;#<value> and when you assign a person to that field the <value> equals the person’s name “Mark Rackley” in my case. This is for Windows Authentication, I would expect this to be different in FBA, but I’m not using FBA. If you want to know what it looks like with FBA you can use the code in this blog and strategically place an alert to see the value.  Anyway… I need to find the name of the user who is currently logged in as it is stored in the person field. This turns out to be one SPServices call: var userName = $().SPServices.SPGetCurrentUser({                     fieldName: "Title",                     debug: false                     }); As you can see, the “Title” field has the information we need. I suspect (although again, I haven’t tried) that the Title field also contains the user’s name as we need it if I was using FBA. Okay… last thing we need to do is store our users name in an array for processing later: myGroups = new Array(); myGroups.push(userName); Find all the SharePoint groups the current user belongs to Now for the groups. How are groups returned in that XML stream?  Same as the person <ID>;#<Group Name>, and if it’s a mutli select it’s all returned in one big long string “<ID>;#<Group Name>;#<ID>;#<Group Name>;#<ID>;#<Group Name>;#<ID>;#<Group Name>;#<ID>;#<Group Name>”.  So, how do we find all the groups the current user belongs to? This is also a simple SPServices call. Using the “GetGroupCollectionFromUser” operation we can find all the groups a user belongs to. So, let’s execute this method and store all our groups. $().SPServices({       operation: "GetGroupCollectionFromUser",       userLoginName: $().SPServices.SPGetCurrentUser(),       async: false,       completefunc: function(xData, Status) {          $(xData.responseXML).find("[nodeName=Group]").each(function() {                 myGroups.push($(this).attr("Name"));          });         }     }); So, all we did in the above code was execute the “GetGroupCollectionFromUser” operation and look for the each “Group” node (row) and store the name for each group in our array that we put the user’s name in previously (myGroups). Now we have an array that contains the current user’s name as it will appear in the person field XML and  all the groups the current user belongs to. The Rest Now comes the easy part for all of you familiar with SPServices. We are going to retrieve our tasks from the Task list using “GetListItems” and look at each entry to see if it belongs to this person. If it does belong to this person we are going to store it for later processing. That code looks something like this: // get list of assigned tasks that aren't closed... *modify the CAML to perform better!*             $().SPServices({                   operation: "GetListItems",                   async: false,                   listName: "Tasks",                   CAMLViewFields: "<ViewFields>" +                             "<FieldRef Name='AssignedTo' />" +                             "<FieldRef Name='Title' />" +                             "<FieldRef Name='StartDate' />" +                             "<FieldRef Name='EndDate' />" +                             "<FieldRef Name='Status' />" +                             "</ViewFields>",                   CAMLQuery: "<Query><Where><And><IsNotNull><FieldRef Name='AssignedTo'/></IsNotNull><Neq><FieldRef Name='Status'/><Value Type='Text'>Completed</Value></Neq></And></Where></Query>",                     completefunc: function (xData, Status) {                         var aDataSet = new Array();                        //loop through each returned Task                         $(xData.responseXML).find("[nodeName=z:row]").each(function() {                             //store the multi-select string of who task is assigned to                             var assignedToString = $(this).attr("ows_AssignedTo");                             found = false;                            //loop through the persons name and all the groups they belong to                             for(var i=0; i<myGroups.length; i++) {                                 //if the person's name or group exists in the assigned To string                                 //then the task is assigned to them                                 if (assignedToString.indexOf(myGroups[i]) >= 0){                                     found = true;                                     break;                                 }                             }                             //if the Task belongs to this person then store or display it                             //(I'm storing it in an array)                             if (found){                                 var thisName = $(this).attr("ows_Title");                                 var thisStartDate = $(this).attr("ows_StartDate");                                 var thisEndDate = $(this).attr("ows_EndDate");                                 var thisStatus = $(this).attr("ows_Status");                                                                  var aDataRow=new Array(                                     thisName,                                     thisStartDate,                                     thisEndDate,                                     thisStatus);                                 aDataSet.push(aDataRow);                             }                          });                          SomeFunctionToDisplayData(aDataSet);                     }                 }); Some notes on why I did certain things and additional caveats. You will notice in my code that I’m doing an AssignedToString.indexOf(GroupName) to see if the task belongs to the person. This could possibly return bad results if you have SharePoint Group names that are named in such a way that the “IndexOf” returns a false positive.  For example if you have a Group called “My Users” and a group called “My Users – SuperUsers” then if a user belonged to “My Users” it would return a false positive on executing “My Users – SuperUsers”.IndexOf(“My Users”). Make sense? Just be aware of this when naming groups, we don’t have this problem. This is where also some fine-tuning can probably be done by those smarter than me. This is a pretty inefficient method to determine if a task belongs to a user, I mean what if a user belongs to 20 groups? That’s a LOT of looping.  See all the opportunities I give you guys to do something fun?? Also, why am I storing my values in an array instead of just writing them out to a Div? Well.. I want to pass my data to a jQuery library to format it all nice and pretty and an Array is a great way to do that. When all is said and done and we put all the code together it looks like:   $(document).ready(function() {         var userName = $().SPServices.SPGetCurrentUser({                     fieldName: "Title",                     debug: false                     });         myGroups = new Array();     myGroups.push(userName );       $().SPServices({       operation: "GetGroupCollectionFromUser",       userLoginName: $().SPServices.SPGetCurrentUser(),       async: false,       completefunc: function(xData, Status) {          $(xData.responseXML).find("[nodeName=Group]").each(function() {                 myGroups.push($(this).attr("Name"));          });                      // get list of assigned tasks that aren't closed... *modify this CAML to perform better!*             $().SPServices({                   operation: "GetListItems",                   async: false,                   listName: "Tasks",                   CAMLViewFields: "<ViewFields>" +                             "<FieldRef Name='AssignedTo' />" +                             "<FieldRef Name='Title' />" +                             "<FieldRef Name='StartDate' />" +                             "<FieldRef Name='EndDate' />" +                             "<FieldRef Name='Status' />" +                             "</ViewFields>",                   CAMLQuery: "<Query><Where><And><IsNotNull><FieldRef Name='AssignedTo'/></IsNotNull><Neq><FieldRef Name='Status'/><Value Type='Text'>Completed</Value></Neq></And></Where></Query>",                     completefunc: function (xData, Status) {                         var aDataSet = new Array();                         //loop through each returned Task                         $(xData.responseXML).find("[nodeName=z:row]").each(function() {                             //store the multi-select string of who task is assigned to                             var assignedToString = $(this).attr("ows_AssignedTo");                             found = false;                            //loop through the persons name and all the groups they belong to                             for(var i=0; i<myGroups.length; i++) {                                 //if the person's name or group exists in the assigned To string                                 //then the task is assigned to them                                 if (assignedToString.indexOf(myGroups[i]) >= 0){                                     found = true;                                     break;                                 }                             }                            //if the Task belongs to this person then store or display it                             //(I'm storing it in an array)                             if (found){                                 var thisName = $(this).attr("ows_Title");                                 var thisStartDate = $(this).attr("ows_StartDate");                                 var thisEndDate = $(this).attr("ows_EndDate");                                 var thisStatus = $(this).attr("ows_Status");                                                                  var aDataRow=new Array(                                     thisName,                                     thisStartDate,                                     thisEndDate,                                     thisStatus);                                 aDataSet.push(aDataRow);                             }                          });                          SomeFunctionToDisplayData(aDataSet);                     }                 });       }    });  }); Final Thoughts So, there you have it. Take it and run with it. Make it something cool (and tell me how you did it). Another possible way to improve performance in this scenario is to use a DVWP to display the tasks and use jQuery and the “myGroups” array from this blog post to hide all those rows that don’t belong to the current user. I haven’t tried it, but it does move some of the processing off to the server (generating the view) so it may perform better.  As always, thanks for stopping by… hope you have a Merry Christmas…

  Read the article

• Matrix Multiplication with C++ AMP

  - by Daniel Moth

  As part of our API tour of C++ AMP, we looked recently at parallel_for_each. I ended that post by saying we would revisit parallel_for_each after introducing array and array_view. Now is the time, so this is part 2 of parallel_for_each, and also a post that brings together everything we've seen until now. The code for serial and accelerated Consider a naïve (or brute force) serial implementation of matrix multiplication  0: void MatrixMultiplySerial(std::vector<float>& vC, const std::vector<float>& vA, const std::vector<float>& vB, int M, int N, int W) 1: { 2: for (int row = 0; row < M; row++) 3: { 4: for (int col = 0; col < N; col++) 5: { 6: float sum = 0.0f; 7: for(int i = 0; i < W; i++) 8: sum += vA[row * W + i] * vB[i * N + col]; 9: vC[row * N + col] = sum; 10: } 11: } 12: } We notice that each loop iteration is independent from each other and so can be parallelized. If in addition we have really large amounts of data, then this is a good candidate to offload to an accelerator. First, I'll just show you an example of what that code may look like with C++ AMP, and then we'll analyze it. It is assumed that you included at the top of your file #include <amp.h> 13: void MatrixMultiplySimple(std::vector<float>& vC, const std::vector<float>& vA, const std::vector<float>& vB, int M, int N, int W) 14: { 15: concurrency::array_view<const float,2> a(M, W, vA); 16: concurrency::array_view<const float,2> b(W, N, vB); 17: concurrency::array_view<concurrency::writeonly<float>,2> c(M, N, vC); 18: concurrency::parallel_for_each(c.grid, 19: [=](concurrency::index<2> idx) restrict(direct3d) { 20: int row = idx[0]; int col = idx[1]; 21: float sum = 0.0f; 22: for(int i = 0; i < W; i++) 23: sum += a(row, i) * b(i, col); 24: c[idx] = sum; 25: }); 26: } First a visual comparison, just for fun: The beginning and end is the same, i.e. lines 0,1,12 are identical to lines 13,14,26. The double nested loop (lines 2,3,4,5 and 10,11) has been transformed into a parallel_for_each call (18,19,20 and 25). The core algorithm (lines 6,7,8,9) is essentially the same (lines 21,22,23,24). We have extra lines in the C++ AMP version (15,16,17). Now let's dig in deeper. Using array_view and extent When we decided to convert this function to run on an accelerator, we knew we couldn't use the std::vector objects in the restrict(direct3d) function. So we had a choice of copying the data to the the concurrency::array<T,N> object, or wrapping the vector container (and hence its data) with a concurrency::array_view<T,N> object from amp.h – here we used the latter (lines 15,16,17). Now we can access the same data through the array_view objects (a and b) instead of the vector objects (vA and vB), and the added benefit is that we can capture the array_view objects in the lambda (lines 19-25) that we pass to the parallel_for_each call (line 18) and the data will get copied on demand for us to the accelerator. Note that line 15 (and ditto for 16 and 17) could have been written as two lines instead of one: extent<2> e(M, W); array_view<const float, 2> a(e, vA); In other words, we could have explicitly created the extent object instead of letting the array_view create it for us under the covers through the constructor overload we chose. The benefit of the extent object in this instance is that we can express that the data is indeed two dimensional, i.e a matrix. When we were using a vector object we could not do that, and instead we had to track via additional unrelated variables the dimensions of the matrix (i.e. with the integers M and W) – aren't you loving C++ AMP already? Note that the const before the float when creating a and b, will result in the underling data only being copied to the accelerator and not be copied back – a nice optimization. A similar thing is happening on line 17 when creating array_view c, where we have indicated that we do not need to copy the data to the accelerator, only copy it back. The kernel dispatch On line 18 we make the call to the C++ AMP entry point (parallel_for_each) to invoke our parallel loop or, as some may say, dispatch our kernel. The first argument we need to pass describes how many threads we want for this computation. For this algorithm we decided that we want exactly the same number of threads as the number of elements in the output matrix, i.e. in array_view c which will eventually update the vector vC. So each thread will compute exactly one result. Since the elements in c are organized in a 2-dimensional manner we can organize our threads in a two-dimensional manner too. We don't have to think too much about how to create the first argument (a grid) since the array_view object helpfully exposes that as a property. Note that instead of c.grid we could have written grid<2>(c.extent) or grid<2>(extent<2>(M, N)) – the result is the same in that we have specified M*N threads to execute our lambda. The second argument is a restrict(direct3d) lambda that accepts an index object. Since we elected to use a two-dimensional extent as the first argument of parallel_for_each, the index will also be two-dimensional and as covered in the previous posts it represents the thread ID, which in our case maps perfectly to the index of each element in the resulting array_view. The kernel itself The lambda body (lines 20-24), or as some may say, the kernel, is the code that will actually execute on the accelerator. It will be called by M*N threads and we can use those threads to index into the two input array_views (a,b) and write results into the output array_view ( c ). The four lines (21-24) are essentially identical to the four lines of the serial algorithm (6-9). The only difference is how we index into a,b,c versus how we index into vA,vB,vC. The code we wrote with C++ AMP is much nicer in its indexing, because the dimensionality is a first class concept, so you don't have to do funny arithmetic calculating the index of where the next row starts, which you have to do when working with vectors directly (since they store all the data in a flat manner). I skipped over describing line 20. Note that we didn't really need to read the two components of the index into temporary local variables. This mostly reflects my personal choice, in some algorithms to break down the index into local variables with names that make sense for the algorithm, i.e. in this case row and col. In other cases it may i,j,k or x,y,z, or M,N or whatever. Also note that we could have written line 24 as: c(idx[0], idx[1])=sum  or  c(row, col)=sum instead of the simpler c[idx]=sum Targeting a specific accelerator Imagine that we had more than one hardware accelerator on a system and we wanted to pick a specific one to execute this parallel loop on. So there would be some code like this anywhere before line 18: vector<accelerator> accs = MyFunctionThatChoosesSuitableAccelerators(); accelerator acc = accs[0]; …and then we would modify line 18 so we would be calling another overload of parallel_for_each that accepts an accelerator_view as the first argument, so it would become: concurrency::parallel_for_each(acc.default_view, c.grid, ...and the rest of your code remains the same… how simple is that? Comments about this post by Daniel Moth welcome at the original blog.

  Read the article

• Linux Kernel crash mutex_lock_slowpath "blocked for more than 120 seconds". What to do?

  - by Roddick

  I have out-of-the box Debian Lenny with non-custom kernel 2.6.26-2-amd64. Brand new server that is used to 5% of it's potential, CPU and Disk-wise. Meaning it probably not crashing because of overload. every few days it freezes with hundreds of these messages in console log: : [284847.828428] INFO: task apache2:12473 blocked for more than 120 seconds. : [284847.868468] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. : [284847.912759] apache2 D ffff8101bc6b7ab0 0 12473 14358 : [284847.912763] ffff810160d5bc50 0000000000000082 ffff8101c0002e40 0000000000000000 : [284847.912766] ffff8101a7c42950 ffff810327d92810 ffff8101a7c42bd8 0000000400000044 : [284847.912770] ffff8101c0002e40 00000000000612d0 0000000000000000 00000040000612d0 : [284847.912773] Call Trace: : [284847.912786] [<ffffffff80429b0d>] __mutex_lock_slowpath+0x64/0x9b : [284847.912790] [<ffffffff80429972>] mutex_lock+0xa/0xb : [284847.912794] [<ffffffff802a20b9>] do_lookup+0x82/0x1c1 : [284847.912800] [<ffffffff802a4271>] __link_path_walk+0x87a/0xd19 : [284847.912805] [<ffffffff80295844>] kmem_getpages+0x96/0x15f : [284847.912808] [<ffffffff80295fb7>] ____cache_alloc_node+0x6d/0x106 : [284847.912814] [<ffffffff802a4756>] path_walk+0x46/0x8b : [284847.912819] [<ffffffff802a4a82>] do_path_lookup+0x158/0x1cf : [284847.912822] [<ffffffff802a3879>] getname+0x140/0x1a7 : [284847.912827] [<ffffffff802a53f1>] __user_walk_fd+0x37/0x4c : [284847.912831] [<ffffffff8029e381>] vfs_lstat_fd+0x18/0x47 : [284847.912840] [<ffffffff8029e3c9>] sys_newlstat+0x19/0x31 : [284847.912848] [<ffffffff8020beda>] system_call_after_swapgs+0x8a/0x8f Almost all traces has __mutex_lock_slowpath as top-level. Only some has different trace: : [284847.737386] INFO: task apache2:12472 blocked for more than 120 seconds. : [284847.777551] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. : [284847.824881] apache2 D ffff8101bc6b7ab0 0 12472 14358 : [284847.824886] ffff8101b9cc1c50 0000000000000086 ffffffffa0131e0a 0000000000000002 : [284847.824889] ffff8102e7454300 ffff810324c6cad0 ffff8102e7454588 0000000000000000 : [284847.824893] 0000000000000001 0000000000000296 0000000000000003 ffff8101b9cc1c58 : [284847.824896] Call Trace: : [284847.828403] [<ffffffffa0131e0a>] :ext3:__ext3_journal_dirty_metadata+0x1e/0x46 : [284847.828412] [<ffffffff80429b0d>] __mutex_lock_slowpath+0x64/0x9b : [284847.828418] [<ffffffff80429972>] mutex_lock+0xa/0xb : [284847.828421] [<ffffffff802a20b9>] do_lookup+0x82/0x1c1 : [284847.828427] [<ffffffff802a4271>] __link_path_walk+0x87a/0xd19 : [284847.828428] [<ffffffff80271296>] find_lock_page+0x1f/0x8a : [284847.828428] [<ffffffff80273182>] filemap_fault+0x1c2/0x33c : [284847.828428] [<ffffffff802a4756>] path_walk+0x46/0x8b : [284847.828428] [<ffffffff802a4a82>] do_path_lookup+0x158/0x1cf : [284847.828428] [<ffffffff802a3879>] getname+0x140/0x1a7 : [284847.828428] [<ffffffff802a53f1>] __user_walk_fd+0x37/0x4c : [284847.828428] [<ffffffff8029e381>] vfs_lstat_fd+0x18/0x47 : [284847.828428] [<ffffffff8029e3c9>] sys_newlstat+0x19/0x31 : [284847.828428] [<ffffffff8020beda>] system_call_after_swapgs+0x8a/0x8f kernel: [1912668.466347] INFO: task apache2:17984 blocked for more than 120 seconds. [1912668.507035] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. : [1912668.555165] apache2 D ffff8101c5637ba0 0 17984 17282 : [1912668.596752] ffff810166a7dd30 0000000000000086 0000000000000000 ffff810166a7dcd8 : [1912668.643341] ffff8101c563c880 ffff81024505f000 0000000000000002 ffff810166a7dd68 : [1912668.699566] 0000000000000086 00000000000cb1a0 0000000000000000 ffff81017f344d60 : [1912668.744773] Call Trace: : [1912668.761754] [<ffffffff8022a3ed>] pick_next_task_fair+0x6e/0x7a : [1912668.829311] [<ffffffff802be0e2>] bio_alloc_bioset+0x89/0xd9 : [1912668.861930] [<ffffffff8024ac3a>] getnstimeofday+0x39/0x98 : [1912668.897005] [<ffffffff802710f6>] sync_page+0x0/0x41 : [1912668.927868] [<ffffffff80429487>] io_schedule+0x5c/0x9e : [1912668.960286] [<ffffffff80271132>] sync_page+0x3c/0x41 : [1912668.991756] [<ffffffff804295fa>] __wait_on_bit_lock+0x36/0x66 : [1912669.031757] [<ffffffff802710e3>] __lock_page+0x5e/0x64 : [1912669.064191] [<ffffffff802461d3>] wake_bit_function+0x0/0x23 : [1912669.100100] [<ffffffff80281bc5>] handle_mm_fault+0x5e4/0x8de : [1912669.134531] [<ffffffff802461a5>] autoremove_wake_function+0x0/0x2e : [1912669.174623] [<ffffffff802aa108>] fcntl_setlk+0x1cf/0x291 : [1912669.210623] [<ffffffff802461a5>] autoremove_wake_function+0x0/0x2e : [1912669.246923] [<ffffffff802a677f>] sys_fcntl+0x280/0x2f7 After googling for "mutex_lock_slowpath" I can only find the Kernel mailing list discussions that this issue was introduced in some commit. Wthout reference to verison. Discussions as recent as Jan 25, 2011. The Kernel I am using is form Debian Lenny, year ago. What should I do? Is this bug even fixed in kernel? if it's such obvious bug why it happens so rarely? Should I download latest kernel from kernel.org and upgrade? Should I use Debian backports to install new "Approved" kernel? Am I missing something? What to do?

  Read the article

• Clean Code Development & Flexible work environment - MSCC 26.10.2013

  Finally, some spare time to summarize my impressions and experiences of the recent meetup of Mauritius Software Craftsmanship Community. I already posted my comment on the event and on our social media networks: Professional - It's getting better with our meetups and I really appreciated that 'seniors' and 'juniors' were present today. Despite running a little bit out of time it was really great to see more students coming to the gathering. This time we changed location for our Saturday meetup and it worked out very well. A big thank you to Ebene Accelerator, namely Mrs Poonum, for the ability to use their meeting rooms for our community get-together. Already some weeks ago I had a very pleasant conversation with her about the MSCC aims, 'mission' and how we organise things. Additionally, I think that an environment like the Ebene Accelerator is a good choice as it acts as an incubator for young developers and start-ups. Reactions from other craftsmen Before I put my thoughts about our recent meeting down, I'd like to mention and cross-link to some of the other craftsmen that were present: "MSCC meet up is a massive knowledge gaining strategies for students, future entrepreneurs, or for geeks all around. Knowledge sharing becomes a fun. For those who have not been able to made it do subscribe on our MSCC meet up group at meetup.com." -- Nitin on Learning is fun with #MSCC #Ebene Accelerator "We then talked about the IT industry in Mauritius, salary issues in various field like system administration, software development etc. We analysed the reasons why people tend to hop from one company to another. That was a fun debate." -- Ish on MSCC meetup - Gang of Geeks "Flexible Learning Environment was quite interesting since these lines struck cords : "You're not a secretary....9 to 5 shouldn't suit you"....This allowed reflection...deep reflection....especially regarding the local mindset...which should be changed in a way which would promote creativity rather than choking it till death..." -- Yannick on 2nd MSCC Monthly Meet-up And others on Facebook... ;-) Visual impressions are available on our Meetup event page. More first time attendees We great pleasure I noticed that we have once again more first time visitors. A quick overlook showed that we had a majority of UoM students in first, second or last year. Some of them are already participating in the UoM Computer Club or are nominated as members of the Microsoft Student Partner (MSP) programme. Personally, I really appreciate the fact that the MSCC is able to gather such a broad audience. And as I wrote initially, the MSCC is technology-agnostic; we want IT people from any segment of this business. Of course, students which are about to delve into the 'real world' of working are highly welcome, and I hope that they might get one or other glimpse of experience or advice from employees. Sticking to the schedule? No, not really... And honestly, it was a good choice to go a little bit of the beaten tracks. I mean, yes we have a 'rough' agenda of topics that we would like to talk about or having a presentation about. But we keep it 'agile'. Due to the high number of new faces, we initiated another quick round of introductions and I gave a really brief overview of the MSCC. Next, we started to reflect on the Clean Code Developer (CCD) - Red Grade which we introduced on the last meetup. Nirvan was the lucky one and he did a good job on summarizing the various abbreviations of the first level of being a CCD. Actually, more interesting, we exchanged experience about the principles and practices of Red Grade, and it was very informative to get to know that Yann actually 'interviewed' a couple of friends, other students, local guys working in IT companies as well as some IT friends from India in order to counter-check on what he learned first-hand about Clean Code. Currently, he is reading the book of Robert C. Martin on that topic and I'm looking forward to his review soon. More output generates more input What seems to be like a personal mantra is working out pretty well for me since the beginning of this year. Being more active on social media networks, writing more article on my blog, starting the Mauritius Software Craftsmanship Community, and contributing more to other online communities has helped me to receive more project requests, job offers and possibilities to expand my business at IOS Indian Ocean Software Ltd. Actually, it is not a coincidence that one of the questions new craftsmen should answer during registration asks about having a personal blog. Whether you are just curious about IT, right in the middle of your Computer Studies, or already working in software development or system administration since a while you should consider to advertise and market yourself online. Easiest way to resolve this are to have online profiles on professional social media networks like LinkedIn, Xing, Twitter, and Google+ (no Facebook should be considered for private only), and considering to have a personal blog. Why? -- Be yourself, be proud of your work, and let other people know that you're passionate about your profession. Trust me, this is going to open up opportunities you might not have dreamt about... Exchanging ideas about having a professional online presence - MSCC meetup on the 26th October 2013 Furthermore, consider to put your Curriculum Vitae online, too. There are quite a number of service providers like 1ClickCV, Stack Overflow Careers 2.0, etc. which give you the ability to have an up to date CV online. At least put it on your site, next to your personal blog. Similar to what you would be able to see on my site here. Cyber Island Mauritius - are we there? A couple of weeks ago I got a 'cold' message on LinkedIn from someone living in the U.S. asking about the circumstances and conditions of the IT world of Mauritius. He has a great business idea, venture capital and is currently looking for a team of software developers (mainly mobile - iOS) for a new startup here in Mauritius. Since then we exchanged quite some details through private messages and Skype conversations, and I suggested that it might be a good chance to join our meetup through a conference call and see for yourself about potential candidates. During approximately 30 to 40 minutes the brief idea of the new startup was presented - very promising state-of-the-art technology aspects and integration of various public APIs -, and we had a good Q&A session about it. Also thanks to the excellent bandwidth provided by the Ebene Accelerator the video conference between three parties went absolutely well. Clean Code Developer - Orange Grade Hahaha - nice one... Being at the Orange Tower at Ebene and then talking about an Orange Grade as CCD. Well, once again I provided an overview of the principles and practices in that rank of Clean Code, and similar to our last meetup we discussed on the various aspect of each principle, whether someone already got in touch with it during studies or work, and how it could affect their future view on their source code. Following are the principles and practices of Clean Code Developer - Orange Grade: CCD Orange Grade - Principles Single Level of Abstraction (SLA) Single Responsibility Principle (SRP) Separation of Concerns (SoC) Source Code conventions CCD Orange Grade - Practices Issue Tracking Automated Integration Tests Reading, Reading, Reading Reviews Especially the part on reading technical books got some extra attention. We quickly gathered our views on that and came up with a result that ranges between Zero (0) and up to Fifteen (15) book titles per year. Personally, I'm keeping my progress between Six (6) and Eight (8) titles per year, but at least One (1) per quarter of a year. Which is also connected to the fact that I'm participating in the O'Reilly Reader Review Program and have a another benefit to get access to free books only by writing and publishing a review afterwards. We also had a good exchange on the extended topic of 'Reviews' - which to my opinion is abnormal difficult here in Mauritius for various reasons. As far as I can tell from my experience working with Mauritian software developers, either as colleagues, employees or during consulting services there are unfortunately two dominant pattern on that topic: Keeping quiet Running away Honestly, I have no evidence about why these are the two 'solutions' on reviews but that's the situation that I had to face over the last couple of years. Sitting together and talking about problematic issues, tackling down root causes of de-motivational activities and working on general improvements doesn't seem to have a ground within the IT world of Mauritius. Are you a typist or a creative software craftsman? - MSCC meetup on the 26th October 2013 One very good example that we talked about was the fact of 'job hoppers' as you can easily observe it on someone's CV - those people change job every single year; for no obvious reason! Frankly speaking, I wouldn't even consider an IT person like to for an interview. As a company you're investing money and effort into the abilities of your employees. Hiring someone that won't stay for a longer period is out of question. And sorry to say, these kind of IT guys smell fishy about their capabilities and more likely to cause problems than actually produce productive results. One of the reasons why there is a probation period on an employment contract is to give you the liberty to leave as early as possible in case that you don't like your new position. Don't fool yourself or waste other people's time and money by hanging around a full year only to snatch off the bonus payment... Future outlook: Developer's Conference Even though it is not official yet I already mentioned it several times during our weekly Code & Coffee sessions. The MSCC is looking forward to be able to organise or to contribute to an upcoming IT event. Currently, the rough schedule is set for April 2014 but this mainly depends on availability of location(s), a decent time frame for preparations, and the underlying procedures with public bodies to have it approved and so on. As soon as the information about date and location has been fixed there will be a 'Call for Papers' period in order to attract local IT enthusiasts to apply for a session slot and talk about their field of work and their passion in IT. More to come for sure... My resume of the day It was a great gathering and I am very pleased about the fact that we had another 15 craftsmen (plus 2 businessmen on conference call plus 2 young apprentices) in the same room, talking about IT related topics and sharing their experience as employees and students. Personally, I really appreciated the feedback from the students about their current view on their future career, and I really hope that some of them are going to pursue their dreams. Start promoting yourself and it will happen... Looking forward to your blogs! And last but not least our numbers on Meetup and Facebook have been increased as a direct consequence of this meetup. Please, spread the word about the MSCC and get your friends and colleagues to join our official site. The higher the number of craftsmen we have the better chances we have t achieve something great! Thanks!

  Read the article

• Bridging LXC containers to host eth0 so they can have a public IP

  - by Vianney Stroebel

  UPDATE: I found the solution there: http://www.linuxfoundation.org/collaborate/workgroups/networking/bridge#No_traffic_gets_trough_.28except_ARP_and_STP.29 # cd /proc/sys/net/bridge # ls bridge-nf-call-arptables bridge-nf-call-iptables bridge-nf-call-ip6tables bridge-nf-filter-vlan-tagged # for f in bridge-nf-*; do echo 0 $f; done But I'd like to have expert opinions on this: is it safe to disable all bridge-nf-*? What are they here for? END OF UPDATE I need to bridge LXC containers to the physical interface (eth0) of my host, reading numerous tutorials, documents and blog posts on the subject. I need the containers to have their own public IP (which I've previously done KVM/libvirt). After two days of searching and trying, I still can't make it work with LXC containers. The host runs a freshly installed Ubuntu Server Quantal (12.10) with only libvirt (which I'm not using here) and lxc installed. I created the containers with : lxc-create -t ubuntu -n mycontainer So they also run Ubuntu 12.10. Content of /var/lib/lxc/mycontainer/config is: lxc.utsname = mycontainer lxc.mount = /var/lib/lxc/test/fstab lxc.rootfs = /var/lib/lxc/test/rootfs lxc.network.type = veth lxc.network.flags = up lxc.network.link = br0 lxc.network.name = eth0 lxc.network.veth.pair = vethmycontainer lxc.network.ipv4 = 179.43.46.233 lxc.network.hwaddr= 02:00:00:86:5b:11 lxc.devttydir = lxc lxc.tty = 4 lxc.pts = 1024 lxc.arch = amd64 lxc.cap.drop = sys_module mac_admin mac_override lxc.pivotdir = lxc_putold # uncomment the next line to run the container unconfined: #lxc.aa_profile = unconfined lxc.cgroup.devices.deny = a # Allow any mknod (but not using the node) lxc.cgroup.devices.allow = c *:* m lxc.cgroup.devices.allow = b *:* m # /dev/null and zero lxc.cgroup.devices.allow = c 1:3 rwm lxc.cgroup.devices.allow = c 1:5 rwm # consoles lxc.cgroup.devices.allow = c 5:1 rwm lxc.cgroup.devices.allow = c 5:0 rwm #lxc.cgroup.devices.allow = c 4:0 rwm #lxc.cgroup.devices.allow = c 4:1 rwm # /dev/{,u}random lxc.cgroup.devices.allow = c 1:9 rwm lxc.cgroup.devices.allow = c 1:8 rwm lxc.cgroup.devices.allow = c 136:* rwm lxc.cgroup.devices.allow = c 5:2 rwm # rtc lxc.cgroup.devices.allow = c 254:0 rwm #fuse lxc.cgroup.devices.allow = c 10:229 rwm #tun lxc.cgroup.devices.allow = c 10:200 rwm #full lxc.cgroup.devices.allow = c 1:7 rwm #hpet lxc.cgroup.devices.allow = c 10:228 rwm #kvm lxc.cgroup.devices.allow = c 10:232 rwm Then I changed my host /etc/network/interfaces to: auto lo iface lo inet loopback auto br0 iface br0 inet static bridge_ports eth0 bridge_fd 0 address 92.281.86.226 netmask 255.255.255.0 network 92.281.86.0 broadcast 92.281.86.255 gateway 92.281.86.254 dns-nameservers 213.186.33.99 dns-search ovh.net When I try command line configuration ("brctl addif", "ifconfig eth0", etc.) my remote host becomes inaccessible and I have to hard reboot it. I changed the content of /var/lib/lxc/mycontainer/rootfs/etc/network/interfaces to: auto lo iface lo inet loopback auto eth0 iface eth0 inet static address 179.43.46.233 netmask 255.255.255.255 broadcast 178.33.40.233 gateway 92.281.86.254 It takes several minutes for mycontainer to start (lxc-start -n mycontainer). I tried replacing gateway 92.281.86.254 by : post-up route add 92.281.86.254 dev eth0 post-up route add default gw 92.281.86.254 post-down route del 92.281.86.254 dev eth0 post-down route del default gw 92.281.86.254 My container then starts instantly. But whatever configuration I set in /var/lib/lxc/mycontainer/rootfs/etc/network/interfaces, I cannot ping from mycontainer to any IP (including the host's) : ubuntu@mycontainer:~$ ping 92.281.86.226 PING 92.281.86.226 (92.281.86.226) 56(84) bytes of data. ^C --- 92.281.86.226 ping statistics --- 6 packets transmitted, 0 received, 100% packet loss, time 5031ms And my host cannot ping the container: root@host:~# ping 179.43.46.233 PING 179.43.46.233 (179.43.46.233) 56(84) bytes of data. ^C --- 179.43.46.233 ping statistics --- 5 packets transmitted, 0 received, 100% packet loss, time 4000ms My container's ifconfig: ubuntu@mycontainer:~$ ifconfig eth0 Link encap:Ethernet HWaddr 02:00:00:86:5b:11 inet addr:179.43.46.233 Bcast:255.255.255.255 Mask:0.0.0.0 inet6 addr: fe80::ff:fe79:5a31/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:64 errors:0 dropped:6 overruns:0 frame:0 TX packets:54 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:4070 (4.0 KB) TX bytes:4168 (4.1 KB) lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:32 errors:0 dropped:0 overruns:0 frame:0 TX packets:32 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:2496 (2.4 KB) TX bytes:2496 (2.4 KB) My host's ifconfig: root@host:~# ifconfig br0 Link encap:Ethernet HWaddr 4c:72:b9:43:65:2b inet addr:92.281.86.226 Bcast:91.121.67.255 Mask:255.255.255.0 inet6 addr: fe80::4e72:b9ff:fe43:652b/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:1453 errors:0 dropped:18 overruns:0 frame:0 TX packets:1630 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:145125 (145.1 KB) TX bytes:299943 (299.9 KB) eth0 Link encap:Ethernet HWaddr 4c:72:b9:43:65:2b UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:3178 errors:0 dropped:0 overruns:0 frame:0 TX packets:1637 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:298263 (298.2 KB) TX bytes:309167 (309.1 KB) Interrupt:20 Memory:fe500000-fe520000 lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:6 errors:0 dropped:0 overruns:0 frame:0 TX packets:6 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:300 (300.0 B) TX bytes:300 (300.0 B) vethtest Link encap:Ethernet HWaddr fe:0d:7f:3e:70:88 inet6 addr: fe80::fc0d:7fff:fe3e:7088/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:54 errors:0 dropped:0 overruns:0 frame:0 TX packets:67 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:4168 (4.1 KB) TX bytes:4250 (4.2 KB) virbr0 Link encap:Ethernet HWaddr de:49:c5:66:cf:84 inet addr:192.168.122.1 Bcast:192.168.122.255 Mask:255.255.255.0 UP BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) I have disabled lxcbr0 (USE_LXC_BRIDGE="false" in /etc/default/lxc). root@host:~# brctl show bridge name bridge id STP enabled interfaces br0 8000.4c72b943652b no eth0 vethtest I have configured the IP 179.43.46.233 to point to 02:00:00:86:5b:11 in my hosting provider (OVH) config panel. (The IPs in this post are not the real ones.) Thanks for reading this long question! :-) Vianney

  Read the article

< Previous Page | 500 501 502 503 504 505 506 507 508 509 510 511  | Next Page >