Search Results

Search found 13415 results on 537 pages for 'variable caching'.

Page 516/537 | < Previous Page | 512 513 514 515 516 517 518 519 520 521 522 523  | Next Page >

  • Metro: Introduction to the WinJS ListView Control

    - by Stephen.Walther
    The goal of this blog entry is to provide a quick introduction to the ListView control – just the bare minimum that you need to know to start using the control. When building Metro style applications using JavaScript, the ListView control is the primary control that you use for displaying lists of items. For example, if you are building a product catalog app, then you can use the ListView control to display the list of products. The ListView control supports several advanced features that I plan to discuss in future blog entries. For example, you can group the items in a ListView, you can create master/details views with a ListView, and you can efficiently work with large sets of items with a ListView. In this blog entry, we’ll keep things simple and focus on displaying a list of products. There are three things that you need to do in order to display a list of items with a ListView: Create a data source Create an Item Template Declare the ListView Creating the ListView Data Source The first step is to create (or retrieve) the data that you want to display with the ListView. In most scenarios, you will want to bind a ListView to a WinJS.Binding.List object. The nice thing about the WinJS.Binding.List object is that it enables you to take a standard JavaScript array and convert the array into something that can be bound to the ListView. It doesn’t matter where the JavaScript array comes from. It could be a static array that you declare or you could retrieve the array as the result of an Ajax call to a remote server. The following JavaScript file – named products.js – contains a list of products which can be bound to a ListView. (function () { "use strict"; var products = new WinJS.Binding.List([ { name: "Milk", price: 2.44 }, { name: "Oranges", price: 1.99 }, { name: "Wine", price: 8.55 }, { name: "Apples", price: 2.44 }, { name: "Steak", price: 1.99 }, { name: "Eggs", price: 2.44 }, { name: "Mushrooms", price: 1.99 }, { name: "Yogurt", price: 2.44 }, { name: "Soup", price: 1.99 }, { name: "Cereal", price: 2.44 }, { name: "Pepsi", price: 1.99 } ]); WinJS.Namespace.define("ListViewDemos", { products: products }); })(); The products variable represents a WinJS.Binding.List object. This object is initialized with a plain-old JavaScript array which represents an array of products. To avoid polluting the global namespace, the code above uses the module pattern and exposes the products using a namespace. The list of products is exposed to the world as ListViewDemos.products. To learn more about the module pattern and namespaces in WinJS, see my earlier blog entry: http://stephenwalther.com/blog/archive/2012/02/22/metro-namespaces-and-modules.aspx Creating the ListView Item Template The ListView control does not know how to render anything. It doesn’t know how you want each list item to appear. To get the ListView control to render something useful, you must create an Item Template. Here’s what our template for rendering an individual product looks like: <div id="productTemplate" data-win-control="WinJS.Binding.Template"> <div class="product"> <span data-win-bind="innerText:name"></span> <span data-win-bind="innerText:price"></span> </div> </div> This template displays the product name and price from the data source. Normally, you will declare your template in the same file as you declare the ListView control. In our case, both the template and ListView are declared in the default.html file. To learn more about templates, see my earlier blog entry: http://stephenwalther.com/blog/archive/2012/02/27/metro-using-templates.aspx Declaring the ListView The final step is to declare the ListView control in a page. Here’s the markup for declaring a ListView: <div data-win-control="WinJS.UI.ListView" data-win-options="{ itemDataSource:ListViewDemos.products.dataSource, itemTemplate:select('#productTemplate') }"> </div> You declare a ListView by adding the data-win-control to an HTML DIV tag. The data-win-options attribute is used to set two properties of the ListView. The ListView is associated with its data source with the itemDataSource property. Notice that the data source is ListViewDemos.products.dataSource and not just ListViewDemos.products. You need to associate the ListView with the dataSoure property. The ListView is associated with its item template with the help of the itemTemplate property. The ID of the item template — #productTemplate – is used to select the template from the page. Here’s what the complete version of the default.html page looks like: <!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>ListViewDemos</title> <!-- WinJS references --> <link href="//Microsoft.WinJS.0.6/css/ui-dark.css" rel="stylesheet"> <script src="//Microsoft.WinJS.0.6/js/base.js"></script> <script src="//Microsoft.WinJS.0.6/js/ui.js"></script> <!-- ListViewDemos references --> <link href="/css/default.css" rel="stylesheet"> <script src="/js/default.js"></script> <script src="/js/products.js" type="text/javascript"></script> <style type="text/css"> .product { width: 200px; height: 100px; border: white solid 1px; } </style> </head> <body> <div id="productTemplate" data-win-control="WinJS.Binding.Template"> <div class="product"> <span data-win-bind="innerText:name"></span> <span data-win-bind="innerText:price"></span> </div> </div> <div data-win-control="WinJS.UI.ListView" data-win-options="{ itemDataSource:ListViewDemos.products.dataSource, itemTemplate:select('#productTemplate') }"> </div> </body> </html> Notice that the page above includes a reference to the products.js file: <script src=”/js/products.js” type=”text/javascript”></script> The page above also contains a Template control which contains the ListView item template. Finally, the page includes the declaration of the ListView control. Summary The goal of this blog entry was to describe the minimal set of steps which you must complete to use the WinJS ListView control to display a simple list of items. You learned how to create a data source, declare an item template, and declare a ListView control.

    Read the article

  • Rendering ASP.NET MVC Views to String

    - by Rick Strahl
    It's not uncommon in my applications that I require longish text output that does not have to be rendered into the HTTP output stream. The most common scenario I have for 'template driven' non-Web text is for emails of all sorts. Logon confirmations and verifications, email confirmations for things like orders, status updates or scheduler notifications - all of which require merged text output both within and sometimes outside of Web applications. On other occasions I also need to capture the output from certain views for logging purposes. Rather than creating text output in code, it's much nicer to use the rendering mechanism that ASP.NET MVC already provides by way of it's ViewEngines - using Razor or WebForms views - to render output to a string. This is nice because it uses the same familiar rendering mechanism that I already use for my HTTP output and it also solves the problem of where to store the templates for rendering this content in nothing more than perhaps a separate view folder. The good news is that ASP.NET MVC's rendering engine is much more modular than the full ASP.NET runtime engine which was a real pain in the butt to coerce into rendering output to string. With MVC the rendering engine has been separated out from core ASP.NET runtime, so it's actually a lot easier to get View output into a string. Getting View Output from within an MVC Application If you need to generate string output from an MVC and pass some model data to it, the process to capture this output is fairly straight forward and involves only a handful of lines of code. The catch is that this particular approach requires that you have an active ControllerContext that can be passed to the view. This means that the following approach is limited to access from within Controller methods. Here's a class that wraps the process and provides both instance and static methods to handle the rendering:/// <summary> /// Class that renders MVC views to a string using the /// standard MVC View Engine to render the view. /// /// Note: This class can only be used within MVC /// applications that have an active ControllerContext. /// </summary> public class ViewRenderer { /// <summary> /// Required Controller Context /// </summary> protected ControllerContext Context { get; set; } public ViewRenderer(ControllerContext controllerContext) { Context = controllerContext; } /// <summary> /// Renders a full MVC view to a string. Will render with the full MVC /// View engine including running _ViewStart and merging into _Layout /// </summary> /// <param name="viewPath"> /// The path to the view to render. Either in same controller, shared by /// name or as fully qualified ~/ path including extension /// </param> /// <param name="model">The model to render the view with</param> /// <returns>String of the rendered view or null on error</returns> public string RenderView(string viewPath, object model) { return RenderViewToStringInternal(viewPath, model, false); } /// <summary> /// Renders a partial MVC view to string. Use this method to render /// a partial view that doesn't merge with _Layout and doesn't fire /// _ViewStart. /// </summary> /// <param name="viewPath"> /// The path to the view to render. Either in same controller, shared by /// name or as fully qualified ~/ path including extension /// </param> /// <param name="model">The model to pass to the viewRenderer</param> /// <returns>String of the rendered view or null on error</returns> public string RenderPartialView(string viewPath, object model) { return RenderViewToStringInternal(viewPath, model, true); } public static string RenderView(string viewPath, object model, ControllerContext controllerContext) { ViewRenderer renderer = new ViewRenderer(controllerContext); return renderer.RenderView(viewPath, model); } public static string RenderPartialView(string viewPath, object model, ControllerContext controllerContext) { ViewRenderer renderer = new ViewRenderer(controllerContext); return renderer.RenderPartialView(viewPath, model); } protected string RenderViewToStringInternal(string viewPath, object model, bool partial = false) { // first find the ViewEngine for this view ViewEngineResult viewEngineResult = null; if (partial) viewEngineResult = ViewEngines.Engines.FindPartialView(Context, viewPath); else viewEngineResult = ViewEngines.Engines.FindView(Context, viewPath, null); if (viewEngineResult == null) throw new FileNotFoundException(Properties.Resources.ViewCouldNotBeFound); // get the view and attach the model to view data var view = viewEngineResult.View; Context.Controller.ViewData.Model = model; string result = null; using (var sw = new StringWriter()) { var ctx = new ViewContext(Context, view, Context.Controller.ViewData, Context.Controller.TempData, sw); view.Render(ctx, sw); result = sw.ToString(); } return result; } } The key is the RenderViewToStringInternal method. The method first tries to find the view to render based on its path which can either be in the current controller's view path or the shared view path using its simple name (PasswordRecovery) or alternately by its full virtual path (~/Views/Templates/PasswordRecovery.cshtml). This code should work both for Razor and WebForms views although I've only tried it with Razor Views. Note that WebForms Views might actually be better for plain text as Razor adds all sorts of white space into its output when there are code blocks in the template. The Web Forms engine provides more accurate rendering for raw text scenarios. Once a view engine is found the view to render can be retrieved. Views in MVC render based on data that comes off the controller like the ViewData which contains the model along with the actual ViewData and ViewBag. From the View and some of the Context data a ViewContext is created which is then used to render the view with. The View picks up the Model and other data from the ViewContext internally and processes the View the same it would be processed if it were to send its output into the HTTP output stream. The difference is that we can override the ViewContext's output stream which we provide and capture into a StringWriter(). After rendering completes the result holds the output string. If an error occurs the error behavior is similar what you see with regular MVC errors - you get a full yellow screen of death including the view error information with the line of error highlighted. It's your responsibility to handle the error - or let it bubble up to your regular Controller Error filter if you have one. To use the simple class you only need a single line of code if you call the static methods. Here's an example of some Controller code that is used to send a user notification to a customer via email in one of my applications:[HttpPost] public ActionResult ContactSeller(ContactSellerViewModel model) { InitializeViewModel(model); var entryBus = new busEntry(); var entry = entryBus.LoadByDisplayId(model.EntryId); if ( string.IsNullOrEmpty(model.Email) ) entryBus.ValidationErrors.Add("Email address can't be empty.","Email"); if ( string.IsNullOrEmpty(model.Message)) entryBus.ValidationErrors.Add("Message can't be empty.","Message"); model.EntryId = entry.DisplayId; model.EntryTitle = entry.Title; if (entryBus.ValidationErrors.Count > 0) { ErrorDisplay.AddMessages(entryBus.ValidationErrors); ErrorDisplay.ShowError("Please correct the following:"); } else { string message = ViewRenderer.RenderView("~/views/template/ContactSellerEmail.cshtml",model, ControllerContext); string title = entry.Title + " (" + entry.DisplayId + ") - " + App.Configuration.ApplicationName; AppUtils.SendEmail(title, message, model.Email, entry.User.Email, false, false)) } return View(model); } Simple! The view in this case is just a plain MVC view and in this case it's a very simple plain text email message (edited for brevity here) that is created and sent off:@model ContactSellerViewModel @{ Layout = null; }re: @Model.EntryTitle @Model.ListingUrl @Model.Message ** SECURITY ADVISORY - AVOID SCAMS ** Avoid: wiring money, cross-border deals, work-at-home ** Beware: cashier checks, money orders, escrow, shipping ** More Info: @(App.Configuration.ApplicationBaseUrl)scams.html Obviously this is a very simple view (I edited out more from this page to keep it brief) -  but other template views are much more complex HTML documents or long messages that are occasionally updated and they are a perfect fit for Razor rendering. It even works with nested partial views and _layout pages. Partial Rendering Notice that I'm rendering a full View here. In the view I explicitly set the Layout=null to avoid pulling in _layout.cshtml for this view. This can also be controlled externally by calling the RenderPartial method instead: string message = ViewRenderer.RenderPartialView("~/views/template/ContactSellerEmail.cshtml",model, ControllerContext); with this line of code no layout page (or _viewstart) will be loaded, so the output generated is just what's in the view. I find myself using Partials most of the time when rendering templates, since the target of templates usually tend to be emails or other HTML fragment like output, so the RenderPartialView() method is definitely useful to me. Rendering without a ControllerContext The preceding class is great when you're need template rendering from within MVC controller actions or anywhere where you have access to the request Controller. But if you don't have a controller context handy - maybe inside a utility function that is static, a non-Web application, or an operation that runs asynchronously in ASP.NET - which makes using the above code impossible. I haven't found a way to manually create a Controller context to provide the ViewContext() what it needs from outside of the MVC infrastructure. However, there are ways to accomplish this,  but they are a bit more complex. It's possible to host the RazorEngine on your own, which side steps all of the MVC framework and HTTP and just deals with the raw rendering engine. I wrote about this process in Hosting the Razor Engine in Non-Web Applications a long while back. It's quite a process to create a custom Razor engine and runtime, but it allows for all sorts of flexibility. There's also a RazorEngine CodePlex project that does something similar. I've been meaning to check out the latter but haven't gotten around to it since I have my own code to do this. The trick to hosting the RazorEngine to have it behave properly inside of an ASP.NET application and properly cache content so templates aren't constantly rebuild and reparsed. Anyway, in the same app as above I have one scenario where no ControllerContext is available: I have a background scheduler running inside of the app that fires on timed intervals. This process could be external but because it's lightweight we decided to fire it right inside of the ASP.NET app on a separate thread. In my app the code that renders these templates does something like this:var model = new SearchNotificationViewModel() { Entries = entries, Notification = notification, User = user }; // TODO: Need logging for errors sending string razorError = null; var result = AppUtils.RenderRazorTemplate("~/views/template/SearchNotificationTemplate.cshtml", model, razorError); which references a couple of helper functions that set up my RazorFolderHostContainer class:public static string RenderRazorTemplate(string virtualPath, object model,string errorMessage = null) { var razor = AppUtils.CreateRazorHost(); var path = virtualPath.Replace("~/", "").Replace("~", "").Replace("/", "\\"); var merged = razor.RenderTemplateToString(path, model); if (merged == null) errorMessage = razor.ErrorMessage; return merged; } /// <summary> /// Creates a RazorStringHostContainer and starts it /// Call .Stop() when you're done with it. /// /// This is a static instance /// </summary> /// <param name="virtualPath"></param> /// <param name="binBasePath"></param> /// <param name="forceLoad"></param> /// <returns></returns> public static RazorFolderHostContainer CreateRazorHost(string binBasePath = null, bool forceLoad = false) { if (binBasePath == null) { if (HttpContext.Current != null) binBasePath = HttpContext.Current.Server.MapPath("~/"); else binBasePath = AppDomain.CurrentDomain.BaseDirectory; } if (_RazorHost == null || forceLoad) { if (!binBasePath.EndsWith("\\")) binBasePath += "\\"; //var razor = new RazorStringHostContainer(); var razor = new RazorFolderHostContainer(); razor.TemplatePath = binBasePath; binBasePath += "bin\\"; razor.BaseBinaryFolder = binBasePath; razor.UseAppDomain = false; razor.ReferencedAssemblies.Add(binBasePath + "ClassifiedsBusiness.dll"); razor.ReferencedAssemblies.Add(binBasePath + "ClassifiedsWeb.dll"); razor.ReferencedAssemblies.Add(binBasePath + "Westwind.Utilities.dll"); razor.ReferencedAssemblies.Add(binBasePath + "Westwind.Web.dll"); razor.ReferencedAssemblies.Add(binBasePath + "Westwind.Web.Mvc.dll"); razor.ReferencedAssemblies.Add("System.Web.dll"); razor.ReferencedNamespaces.Add("System.Web"); razor.ReferencedNamespaces.Add("ClassifiedsBusiness"); razor.ReferencedNamespaces.Add("ClassifiedsWeb"); razor.ReferencedNamespaces.Add("Westwind.Web"); razor.ReferencedNamespaces.Add("Westwind.Utilities"); _RazorHost = razor; _RazorHost.Start(); //_RazorHost.Engine.Configuration.CompileToMemory = false; } return _RazorHost; } The RazorFolderHostContainer essentially is a full runtime that mimics a folder structure like a typical Web app does including caching semantics and compiling code only if code changes on disk. It maps a folder hierarchy to views using the ~/ path syntax. The host is then configured to add assemblies and namespaces. Unfortunately the engine is not exactly like MVC's Razor - the expression expansion and code execution are the same, but some of the support methods like sections, helpers etc. are not all there so templates have to be a bit simpler. There are other folder hosts provided as well to directly execute templates from strings (using RazorStringHostContainer). The following is an example of an HTML email template @inherits RazorHosting.RazorTemplateFolderHost <ClassifiedsWeb.SearchNotificationViewModel> <html> <head> <title>Search Notifications</title> <style> body { margin: 5px;font-family: Verdana, Arial; font-size: 10pt;} h3 { color: SteelBlue; } .entry-item { border-bottom: 1px solid grey; padding: 8px; margin-bottom: 5px; } </style> </head> <body> Hello @Model.User.Name,<br /> <p>Below are your Search Results for the search phrase:</p> <h3>@Model.Notification.SearchPhrase</h3> <small>since @TimeUtils.ShortDateString(Model.Notification.LastSearch)</small> <hr /> You can see that the syntax is a little different. Instead of the familiar @model header the raw Razor  @inherits tag is used to specify the template base class (which you can extend). I took a quick look through the feature set of RazorEngine on CodePlex (now Github I guess) and the template implementation they use is closer to MVC's razor but there are other differences. In the end don't expect exact behavior like MVC templates if you use an external Razor rendering engine. This is not what I would consider an ideal solution, but it works well enough for this project. My biggest concern is the overhead of hosting a second razor engine in a Web app and the fact that here the differences in template rendering between 'real' MVC Razor views and another RazorEngine really are noticeable. You win some, you lose some It's extremely nice to see that if you have a ControllerContext handy (which probably addresses 99% of Web app scenarios) rendering a view to string using the native MVC Razor engine is pretty simple. Kudos on making that happen - as it solves a problem I see in just about every Web application I work on. But it is a bummer that a ControllerContext is required to make this simple code work. It'd be really sweet if there was a way to render views without being so closely coupled to the ASP.NET or MVC infrastructure that requires a ControllerContext. Alternately it'd be nice to have a way for an MVC based application to create a minimal ControllerContext from scratch - maybe somebody's been down that path. I tried for a few hours to come up with a way to make that work but gave up in the soup of nested contexts (MVC/Controller/View/Http). I suspect going down this path would be similar to hosting the ASP.NET runtime requiring a WorkerRequest. Brrr…. The sad part is that it seems to me that a View should really not require much 'context' of any kind to render output to string. Yes there are a few things that clearly are required like paths to the virtual and possibly the disk paths to the root of the app, but beyond that view rendering should not require much. But, no such luck. For now custom RazorHosting seems to be the only way to make Razor rendering go outside of the MVC context… Resources Full ViewRenderer.cs source code from Westwind.Web.Mvc library Hosting the Razor Engine for Non-Web Applications RazorEngine on GitHub© Rick Strahl, West Wind Technologies, 2005-2012Posted in ASP.NET   ASP.NET  MVC   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

  • Parallelism in .NET – Part 14, The Different Forms of Task

    - by Reed
    Before discussing Task creation and actual usage in concurrent environments, I will briefly expand upon my introduction of the Task class and provide a short explanation of the distinct forms of Task.  The Task Parallel Library includes four distinct, though related, variations on the Task class. In my introduction to the Task class, I focused on the most basic version of Task.  This version of Task, the standard Task class, is most often used with an Action delegate.  This allows you to implement for each task within the task decomposition as a single delegate. Typically, when using the new threading constructs in .NET 4 and the Task Parallel Library, we use lambda expressions to define anonymous methods.  The advantage of using a lambda expression is that it allows the Action delegate to directly use variables in the calling scope.  This eliminates the need to make separate Task classes for Action<T>, Action<T1,T2>, and all of the other Action<…> delegate types.  As an example, suppose we wanted to make a Task to handle the ”Show Splash” task from our earlier decomposition.  Even if this task required parameters, such as a message to display, we could still use an Action delegate specified via a lambda: // Store this as a local variable string messageForSplashScreen = GetSplashScreenMessage(); // Create our task Task showSplashTask = new Task( () => { // We can use variables in our outer scope, // as well as methods scoped to our class! this.DisplaySplashScreen(messageForSplashScreen); }); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } This provides a huge amount of flexibility.  We can use this single form of task for any task which performs an operation, provided the only information we need to track is whether the task has completed successfully or not.  This leads to my first observation: Use a Task with a System.Action delegate for any task for which no result is generated. This observation leads to an obvious corollary: we also need a way to define a task which generates a result.  The Task Parallel Library provides this via the Task<TResult> class. Task<TResult> subclasses the standard Task class, providing one additional feature – the ability to return a value back to the user of the task.  This is done by switching from providing an Action delegate to providing a Func<TResult> delegate.  If we decompose our problem, and we realize we have one task where its result is required by a future operation, this can be handled via Task<TResult>.  For example, suppose we want to make a task for our “Check for Update” task, we could do: Task<bool> checkForUpdateTask = new Task<bool>( () => { return this.CheckWebsiteForUpdate(); }); Later, we would start this task, and perform some other work.  At any point in the future, we could get the value from the Task<TResult>.Result property, which will cause our thread to block until the task has finished processing: // This uses Task<bool> checkForUpdateTask generated above... // Start the task, typically on a background thread checkForUpdateTask.Start(); // Do some other work on our current thread this.DoSomeWork(); // Discover, from our background task, whether an update is available // This will block until our task completes bool updateAvailable = checkForUpdateTask.Result; This leads me to my second observation: Use a Task<TResult> with a System.Func<TResult> delegate for any task which generates a result. Task and Task<TResult> provide a much cleaner alternative to the previous Asynchronous Programming design patterns in the .NET framework.  Instead of trying to implement IAsyncResult, and providing BeginXXX() and EndXXX() methods, implementing an asynchronous programming API can be as simple as creating a method that returns a Task or Task<TResult>.  The client side of the pattern also is dramatically simplified – the client can call a method, then either choose to call task.Wait() or use task.Result when it needs to wait for the operation’s completion. While this provides a much cleaner model for future APIs, there is quite a bit of infrastructure built around the current Asynchronous Programming design patterns.  In order to provide a model to work with existing APIs, two other forms of Task exist.  There is a constructor for Task which takes an Action<Object> and a state parameter.  In addition, there is a constructor for creating a Task<TResult> which takes a Func<Object, TResult> as well as a state parameter.  When using these constructors, the state parameter is stored in the Task.AsyncState property. While these two overloads exist, and are usable directly, I strongly recommend avoiding this for new development.  The two forms of Task which take an object state parameter exist primarily for interoperability with traditional .NET Asynchronous Programming methodologies.  Using lambda expressions to capture variables from the scope of the creator is a much cleaner approach than using the untyped state parameters, since lambda expressions provide full type safety without introducing new variables.

    Read the article

  • Parallelism in .NET – Part 18, Task Continuations with Multiple Tasks

    - by Reed
    In my introduction to Task continuations I demonstrated how the Task class provides a more expressive alternative to traditional callbacks.  Task continuations provide a much cleaner syntax to traditional callbacks, but there are other reasons to switch to using continuations… Task continuations provide a clean syntax, and a very simple, elegant means of synchronizing asynchronous method results with the user interface.  In addition, continuations provide a very simple, elegant means of working with collections of tasks. Prior to .NET 4, working with multiple related asynchronous method calls was very tricky.  If, for example, we wanted to run two asynchronous operations, followed by a single method call which we wanted to run when the first two methods completed, we’d have to program all of the handling ourselves.  We would likely need to take some approach such as using a shared callback which synchronized against a common variable, or using a WaitHandle shared within the callbacks to allow one to wait for the second.  Although this could be accomplished easily enough, it requires manually placing this handling into every algorithm which requires this form of blocking.  This is error prone, difficult, and can easily lead to subtle bugs. Similar to how the Task class static methods providing a way to block until multiple tasks have completed, TaskFactory contains static methods which allow a continuation to be scheduled upon the completion of multiple tasks: TaskFactory.ContinueWhenAll. This allows you to easily specify a single delegate to run when a collection of tasks has completed.  For example, suppose we have a class which fetches data from the network.  This can be a long running operation, and potentially fail in certain situations, such as a server being down.  As a result, we have three separate servers which we will “query” for our information.  Now, suppose we want to grab data from all three servers, and verify that the results are the same from all three. With traditional asynchronous programming in .NET, this would require using three separate callbacks, and managing the synchronization between the various operations ourselves.  The Task and TaskFactory classes simplify this for us, allowing us to write: var server1 = Task.Factory.StartNew( () => networkClass.GetResults(firstServer) ); var server2 = Task.Factory.StartNew( () => networkClass.GetResults(secondServer) ); var server3 = Task.Factory.StartNew( () => networkClass.GetResults(thirdServer) ); var result = Task.Factory.ContinueWhenAll( new[] {server1, server2, server3 }, (tasks) => { // Propogate exceptions (see below) Task.WaitAll(tasks); return this.CompareTaskResults( tasks[0].Result, tasks[1].Result, tasks[2].Result); }); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } This is clean, simple, and elegant.  The one complication is the Task.WaitAll(tasks); statement. Although the continuation will not complete until all three tasks (server1, server2, and server3) have completed, there is a potential snag.  If the networkClass.GetResults method fails, and raises an exception, we want to make sure to handle it cleanly.  By using Task.WaitAll, any exceptions raised within any of our original tasks will get wrapped into a single AggregateException by the WaitAll method, providing us a simplified means of handling the exceptions.  If we wait on the continuation, we can trap this AggregateException, and handle it cleanly.  Without this line, it’s possible that an exception could remain uncaught and unhandled by a task, which later might trigger a nasty UnobservedTaskException.  This would happen any time two of our original tasks failed. Just as we can schedule a continuation to occur when an entire collection of tasks has completed, we can just as easily setup a continuation to run when any single task within a collection completes.  If, for example, we didn’t need to compare the results of all three network locations, but only use one, we could still schedule three tasks.  We could then have our completion logic work on the first task which completed, and ignore the others.  This is done via TaskFactory.ContinueWhenAny: var server1 = Task.Factory.StartNew( () => networkClass.GetResults(firstServer) ); var server2 = Task.Factory.StartNew( () => networkClass.GetResults(secondServer) ); var server3 = Task.Factory.StartNew( () => networkClass.GetResults(thirdServer) ); var result = Task.Factory.ContinueWhenAny( new[] {server1, server2, server3 }, (firstTask) => { return this.ProcessTaskResult(firstTask.Result); }); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Here, instead of working with all three tasks, we’re just using the first task which finishes.  This is very useful, as it allows us to easily work with results of multiple operations, and “throw away” the others.  However, you must take care when using ContinueWhenAny to properly handle exceptions.  At some point, you should always wait on each task (or use the Task.Result property) in order to propogate any exceptions raised from within the task.  Failing to do so can lead to an UnobservedTaskException.

    Read the article

  • Creating a dynamic proxy generator with c# – Part 3 – Creating the constructors

    - by SeanMcAlinden
    Creating a dynamic proxy generator with c# – Part 1 – Creating the Assembly builder, Module builder and caching mechanism Creating a dynamic proxy generator with c# – Part 2 – Interceptor Design For the latest code go to http://rapidioc.codeplex.com/ When building our proxy type, the first thing we need to do is build the constructors. There needs to be a corresponding constructor for each constructor on the passed in base type. We also want to create a field to store the interceptors and construct this list within each constructor. So assuming the passed in base type is a User<int, IRepository> class, were looking to generate constructor code like the following:   Default Constructor public User`2_RapidDynamicBaseProxy() {     this.interceptors = new List<IInterceptor<User<int, IRepository>>>();     DefaultInterceptor<User<int, IRepository>> item = new DefaultInterceptor<User<int, IRepository>>();     this.interceptors.Add(item); }     Parameterised Constructor public User`2_RapidDynamicBaseProxy(IRepository repository1) : base(repository1) {     this.interceptors = new List<IInterceptor<User<int, IRepository>>>();     DefaultInterceptor<User<int, IRepository>> item = new DefaultInterceptor<User<int, IRepository>>();     this.interceptors.Add(item); }   As you can see, we first populate a field on the class with a new list of the passed in base type. Construct our DefaultInterceptor class. Add the DefaultInterceptor instance to our interceptor collection. Although this seems like a relatively small task, there is a fair amount of work require to get this going. Instead of going through every line of code – please download the latest from http://rapidioc.codeplex.com/ and debug through. In this post I’m going to concentrate on explaining how it works. TypeBuilder The TypeBuilder class is the main class used to create the type. You instantiate a new TypeBuilder using the assembly module we created in part 1. /// <summary> /// Creates a type builder. /// </summary> /// <typeparam name="TBase">The type of the base class to be proxied.</typeparam> public static TypeBuilder CreateTypeBuilder<TBase>() where TBase : class {     TypeBuilder typeBuilder = DynamicModuleCache.Get.DefineType         (             CreateTypeName<TBase>(),             TypeAttributes.Class | TypeAttributes.Public,             typeof(TBase),             new Type[] { typeof(IProxy) }         );       if (typeof(TBase).IsGenericType)     {         GenericsHelper.MakeGenericType(typeof(TBase), typeBuilder);     }       return typeBuilder; }   private static string CreateTypeName<TBase>() where TBase : class {     return string.Format("{0}_RapidDynamicBaseProxy", typeof(TBase).Name); } As you can see, I’ve create a new public class derived from TBase which also implements my IProxy interface, this is used later for adding interceptors. If the base type is generic, the following GenericsHelper.MakeGenericType method is called. GenericsHelper using System; using System.Reflection.Emit; namespace Rapid.DynamicProxy.Types.Helpers {     /// <summary>     /// Helper class for generic types and methods.     /// </summary>     internal static class GenericsHelper     {         /// <summary>         /// Makes the typeBuilder a generic.         /// </summary>         /// <param name="concrete">The concrete.</param>         /// <param name="typeBuilder">The type builder.</param>         public static void MakeGenericType(Type baseType, TypeBuilder typeBuilder)         {             Type[] genericArguments = baseType.GetGenericArguments();               string[] genericArgumentNames = GetArgumentNames(genericArguments);               GenericTypeParameterBuilder[] genericTypeParameterBuilder                 = typeBuilder.DefineGenericParameters(genericArgumentNames);               typeBuilder.MakeGenericType(genericTypeParameterBuilder);         }           /// <summary>         /// Gets the argument names from an array of generic argument types.         /// </summary>         /// <param name="genericArguments">The generic arguments.</param>         public static string[] GetArgumentNames(Type[] genericArguments)         {             string[] genericArgumentNames = new string[genericArguments.Length];               for (int i = 0; i < genericArguments.Length; i++)             {                 genericArgumentNames[i] = genericArguments[i].Name;             }               return genericArgumentNames;         }     } }       As you can see, I’m getting all of the generic argument types and names, creating a GenericTypeParameterBuilder and then using the typeBuilder to make the new type generic. InterceptorsField The interceptors field will store a List<IInterceptor<TBase>>. Fields are simple made using the FieldBuilder class. The following code demonstrates how to create the interceptor field. FieldBuilder interceptorsField = typeBuilder.DefineField(     "interceptors",     typeof(System.Collections.Generic.List<>).MakeGenericType(typeof(IInterceptor<TBase>)),       FieldAttributes.Private     ); The field will now exist with the new Type although it currently has no data – we’ll deal with this in the constructor. Add method for interceptorsField To enable us to add to the interceptorsField list, we are going to utilise the Add method that already exists within the System.Collections.Generic.List class. We still however have to create the methodInfo necessary to call the add method. This can be done similar to the following: Add Interceptor Field MethodInfo addInterceptor = typeof(List<>)     .MakeGenericType(new Type[] { typeof(IInterceptor<>).MakeGenericType(typeof(TBase)) })     .GetMethod     (        "Add",        BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic,        null,        new Type[] { typeof(IInterceptor<>).MakeGenericType(typeof(TBase)) },        null     ); So we’ve create a List<IInterceptor<TBase>> type, then using the type created a method info called Add which accepts an IInterceptor<TBase>. Now in our constructor we can use this to call this.interceptors.Add(// interceptor); Building the Constructors This will be the first hard-core part of the proxy building process so I’m going to show the class and then try to explain what everything is doing. For a clear view, download the source from http://rapidioc.codeplex.com/, go to the test project and debug through the constructor building section. Anyway, here it is: DynamicConstructorBuilder using System; using System.Collections.Generic; using System.Reflection; using System.Reflection.Emit; using Rapid.DynamicProxy.Interception; using Rapid.DynamicProxy.Types.Helpers; namespace Rapid.DynamicProxy.Types.Constructors {     /// <summary>     /// Class for creating the proxy constructors.     /// </summary>     internal static class DynamicConstructorBuilder     {         /// <summary>         /// Builds the constructors.         /// </summary>         /// <typeparam name="TBase">The base type.</typeparam>         /// <param name="typeBuilder">The type builder.</param>         /// <param name="interceptorsField">The interceptors field.</param>         public static void BuildConstructors<TBase>             (                 TypeBuilder typeBuilder,                 FieldBuilder interceptorsField,                 MethodInfo addInterceptor             )             where TBase : class         {             ConstructorInfo interceptorsFieldConstructor = CreateInterceptorsFieldConstructor<TBase>();               ConstructorInfo defaultInterceptorConstructor = CreateDefaultInterceptorConstructor<TBase>();               ConstructorInfo[] constructors = typeof(TBase).GetConstructors();               foreach (ConstructorInfo constructorInfo in constructors)             {                 CreateConstructor<TBase>                     (                         typeBuilder,                         interceptorsField,                         interceptorsFieldConstructor,                         defaultInterceptorConstructor,                         addInterceptor,                         constructorInfo                     );             }         }           #region Private Methods           private static void CreateConstructor<TBase>             (                 TypeBuilder typeBuilder,                 FieldBuilder interceptorsField,                 ConstructorInfo interceptorsFieldConstructor,                 ConstructorInfo defaultInterceptorConstructor,                 MethodInfo AddDefaultInterceptor,                 ConstructorInfo constructorInfo             ) where TBase : class         {             Type[] parameterTypes = GetParameterTypes(constructorInfo);               ConstructorBuilder constructorBuilder = CreateConstructorBuilder(typeBuilder, parameterTypes);               ILGenerator cIL = constructorBuilder.GetILGenerator();               LocalBuilder defaultInterceptorMethodVariable =                 cIL.DeclareLocal(typeof(DefaultInterceptor<>).MakeGenericType(typeof(TBase)));               ConstructInterceptorsField(interceptorsField, interceptorsFieldConstructor, cIL);               ConstructDefaultInterceptor(defaultInterceptorConstructor, cIL, defaultInterceptorMethodVariable);               AddDefaultInterceptorToInterceptorsList                 (                     interceptorsField,                     AddDefaultInterceptor,                     cIL,                     defaultInterceptorMethodVariable                 );               CreateConstructor(constructorInfo, parameterTypes, cIL);         }           private static void CreateConstructor(ConstructorInfo constructorInfo, Type[] parameterTypes, ILGenerator cIL)         {             cIL.Emit(OpCodes.Ldarg_0);               if (parameterTypes.Length > 0)             {                 LoadParameterTypes(parameterTypes, cIL);             }               cIL.Emit(OpCodes.Call, constructorInfo);             cIL.Emit(OpCodes.Ret);         }           private static void LoadParameterTypes(Type[] parameterTypes, ILGenerator cIL)         {             for (int i = 1; i <= parameterTypes.Length; i++)             {                 cIL.Emit(OpCodes.Ldarg_S, i);             }         }           private static void AddDefaultInterceptorToInterceptorsList             (                 FieldBuilder interceptorsField,                 MethodInfo AddDefaultInterceptor,                 ILGenerator cIL,                 LocalBuilder defaultInterceptorMethodVariable             )         {             cIL.Emit(OpCodes.Ldarg_0);             cIL.Emit(OpCodes.Ldfld, interceptorsField);             cIL.Emit(OpCodes.Ldloc, defaultInterceptorMethodVariable);             cIL.Emit(OpCodes.Callvirt, AddDefaultInterceptor);         }           private static void ConstructDefaultInterceptor             (                 ConstructorInfo defaultInterceptorConstructor,                 ILGenerator cIL,                 LocalBuilder defaultInterceptorMethodVariable             )         {             cIL.Emit(OpCodes.Newobj, defaultInterceptorConstructor);             cIL.Emit(OpCodes.Stloc, defaultInterceptorMethodVariable);         }           private static void ConstructInterceptorsField             (                 FieldBuilder interceptorsField,                 ConstructorInfo interceptorsFieldConstructor,                 ILGenerator cIL             )         {             cIL.Emit(OpCodes.Ldarg_0);             cIL.Emit(OpCodes.Newobj, interceptorsFieldConstructor);             cIL.Emit(OpCodes.Stfld, interceptorsField);         }           private static ConstructorBuilder CreateConstructorBuilder(TypeBuilder typeBuilder, Type[] parameterTypes)         {             return typeBuilder.DefineConstructor                 (                     MethodAttributes.Public | MethodAttributes.SpecialName | MethodAttributes.RTSpecialName                     | MethodAttributes.HideBySig, CallingConventions.Standard, parameterTypes                 );         }           private static Type[] GetParameterTypes(ConstructorInfo constructorInfo)         {             ParameterInfo[] parameterInfoArray = constructorInfo.GetParameters();               Type[] parameterTypes = new Type[parameterInfoArray.Length];               for (int p = 0; p < parameterInfoArray.Length; p++)             {                 parameterTypes[p] = parameterInfoArray[p].ParameterType;             }               return parameterTypes;         }           private static ConstructorInfo CreateInterceptorsFieldConstructor<TBase>() where TBase : class         {             return ConstructorHelper.CreateGenericConstructorInfo                 (                     typeof(List<>),                     new Type[] { typeof(IInterceptor<TBase>) },                     BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic                 );         }           private static ConstructorInfo CreateDefaultInterceptorConstructor<TBase>() where TBase : class         {             return ConstructorHelper.CreateGenericConstructorInfo                 (                     typeof(DefaultInterceptor<>),                     new Type[] { typeof(TBase) },                     BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic                 );         }           #endregion     } } So, the first two tasks within the class should be fairly clear, we are creating a ConstructorInfo for the interceptorField list and a ConstructorInfo for the DefaultConstructor, this is for instantiating them in each contructor. We then using Reflection get an array of all of the constructors in the base class, we then loop through the array and create a corresponding proxy contructor. Hopefully, the code is fairly easy to follow other than some new types and the dreaded Opcodes. ConstructorBuilder This class defines a new constructor on the type. ILGenerator The ILGenerator allows the use of Reflection.Emit to create the method body. LocalBuilder The local builder allows the storage of data in local variables within a method, in this case it’s the constructed DefaultInterceptor. Constructing the interceptors field The first bit of IL you’ll come across as you follow through the code is the following private method used for constructing the field list of interceptors. private static void ConstructInterceptorsField             (                 FieldBuilder interceptorsField,                 ConstructorInfo interceptorsFieldConstructor,                 ILGenerator cIL             )         {             cIL.Emit(OpCodes.Ldarg_0);             cIL.Emit(OpCodes.Newobj, interceptorsFieldConstructor);             cIL.Emit(OpCodes.Stfld, interceptorsField);         } The first thing to know about generating code using IL is that you are using a stack, if you want to use something, you need to push it up the stack etc. etc. OpCodes.ldArg_0 This opcode is a really interesting one, basically each method has a hidden first argument of the containing class instance (apart from static classes), constructors are no different. This is the reason you can use syntax like this.myField. So back to the method, as we want to instantiate the List in the interceptorsField, first we need to load the class instance onto the stack, we then load the new object (new List<TBase>) and finally we store it in the interceptorsField. Hopefully, that should follow easily enough in the method. In each constructor you would now have this.interceptors = new List<User<int, IRepository>>(); Constructing and storing the DefaultInterceptor The next bit of code we need to create is the constructed DefaultInterceptor. Firstly, we create a local builder to store the constructed type. Create a local builder LocalBuilder defaultInterceptorMethodVariable =     cIL.DeclareLocal(typeof(DefaultInterceptor<>).MakeGenericType(typeof(TBase))); Once our local builder is ready, we then need to construct the DefaultInterceptor<TBase> and store it in the variable. Connstruct DefaultInterceptor private static void ConstructDefaultInterceptor     (         ConstructorInfo defaultInterceptorConstructor,         ILGenerator cIL,         LocalBuilder defaultInterceptorMethodVariable     ) {     cIL.Emit(OpCodes.Newobj, defaultInterceptorConstructor);     cIL.Emit(OpCodes.Stloc, defaultInterceptorMethodVariable); } As you can see, using the ConstructorInfo named defaultInterceptorConstructor, we load the new object onto the stack. Then using the store local opcode (OpCodes.Stloc), we store the new object in the local builder named defaultInterceptorMethodVariable. Add the constructed DefaultInterceptor to the interceptors field collection Using the add method created earlier in this post, we are going to add the new DefaultInterceptor object to the interceptors field collection. Add Default Interceptor private static void AddDefaultInterceptorToInterceptorsList     (         FieldBuilder interceptorsField,         MethodInfo AddDefaultInterceptor,         ILGenerator cIL,         LocalBuilder defaultInterceptorMethodVariable     ) {     cIL.Emit(OpCodes.Ldarg_0);     cIL.Emit(OpCodes.Ldfld, interceptorsField);     cIL.Emit(OpCodes.Ldloc, defaultInterceptorMethodVariable);     cIL.Emit(OpCodes.Callvirt, AddDefaultInterceptor); } So, here’s whats going on. The class instance is first loaded onto the stack using the load argument at index 0 opcode (OpCodes.Ldarg_0) (remember the first arg is the hidden class instance). The interceptorsField is then loaded onto the stack using the load field opcode (OpCodes.Ldfld). We then load the DefaultInterceptor object we stored locally using the load local opcode (OpCodes.Ldloc). Then finally we call the AddDefaultInterceptor method using the call virtual opcode (Opcodes.Callvirt). Completing the constructor The last thing we need to do is complete the constructor. Complete the constructor private static void CreateConstructor(ConstructorInfo constructorInfo, Type[] parameterTypes, ILGenerator cIL)         {             cIL.Emit(OpCodes.Ldarg_0);               if (parameterTypes.Length > 0)             {                 LoadParameterTypes(parameterTypes, cIL);             }               cIL.Emit(OpCodes.Call, constructorInfo);             cIL.Emit(OpCodes.Ret);         }           private static void LoadParameterTypes(Type[] parameterTypes, ILGenerator cIL)         {             for (int i = 1; i <= parameterTypes.Length; i++)             {                 cIL.Emit(OpCodes.Ldarg_S, i);             }         } So, the first thing we do again is load the class instance using the load argument at index 0 opcode (OpCodes.Ldarg_0). We then load each parameter using OpCode.Ldarg_S, this opcode allows us to specify an index position for each argument. We then setup calling the base constructor using OpCodes.Call and the base constructors ConstructorInfo. Finally, all methods are required to return, even when they have a void return. As there are no values on the stack after the OpCodes.Call line, we can safely call the OpCode.Ret to give the constructor a void return. If there was a value, we would have to pop the value of the stack before calling return otherwise, the method would try and return a value. Conclusion This was a slightly hardcore post but hopefully it hasn’t been too hard to follow. The main thing is that a number of the really useful opcodes have been used and now the dynamic proxy is capable of being constructed. If you download the code and debug through the tests at http://rapidioc.codeplex.com/, you’ll be able to create proxies at this point, they cannon do anything in terms of interception but you can happily run the tests, call base methods and properties and also take a look at the created assembly in Reflector. Hope this is useful. The next post should be up soon, it will be covering creating the private methods for calling the base class methods and properties. Kind Regards, Sean.

    Read the article

  • Interesting articles and blogs on SPARC T4

    - by mv
    Interesting articles and blogs on SPARC T4 processor   I have consolidated all the interesting information I could get on SPARC T4 processor and its hardware cryptographic capabilities.  Hope its useful. 1. Advantages of SPARC T4 processor  Most important points in this T4 announcement are : "The SPARC T4 processor was designed from the ground up for high speed security and has a cryptographic stream processing unit (SPU) integrated directly into each processor core. These accelerators support 16 industry standard security ciphers and enable high speed encryption at rates 3 to 5 times that of competing processors. By integrating encryption capabilities directly inside the instruction pipeline, the SPARC T4 processor eliminates the performance and cost barriers typically associated with secure computing and makes it possible to deliver high security levels without impacting the user experience." Data Sheet has more details on these  : "New on-chip Encryption Instruction Accelerators with direct non-privileged support for 16 industry-standard cryptographic algorithms plus random number generation in each of the eight cores: AES, Camellia, CRC32c, DES, 3DES, DH, DSA, ECC, Kasumi, MD5, RSA, SHA-1, SHA-224, SHA-256, SHA-384, SHA-512" I ran "isainfo -v" command on Solaris 11 Sparc T4-1 system. It shows the new instructions as expected  : $ isainfo -v 64-bit sparcv9 applications crc32c cbcond pause mont mpmul sha512 sha256 sha1 md5 camellia kasumi des aes ima hpc vis3 fmaf asi_blk_init vis2 vis popc 32-bit sparc applications crc32c cbcond pause mont mpmul sha512 sha256 sha1 md5 camellia kasumi des aes ima hpc vis3 fmaf asi_blk_init vis2 vis popc v8plus div32 mul32  2.  Dan Anderson's Blog have some interesting points about how these can be used : "New T4 crypto instructions include: aes_kexpand0, aes_kexpand1, aes_kexpand2,         aes_eround01, aes_eround23, aes_eround01_l, aes_eround_23_l, aes_dround01, aes_dround23, aes_dround01_l, aes_dround_23_l.       Having SPARC T4 hardware crypto instructions is all well and good, but how do we access it ?      The software is available with Solaris 11 and is used automatically if you are running Solaris a SPARC T4.  It is used internally in the kernel through kernel crypto modules.  It is available in user space through the PKCS#11 library." 3.   Dans' Blog on Where's the Crypto Libraries? Although this was written in 2009 but still is very useful  "Here's a brief tour of the major crypto libraries shown in the digraph:   The libpkcs11 library contains the PKCS#11 API (C_\*() functions, such as C_Initialize()). That in turn calls library pkcs11_softtoken or pkcs11_kernel, for userland or kernel crypto providers. The latter is used mostly for hardware-assisted cryptography (such as n2cp for Niagara2 SPARC processors), as that is performed more efficiently in kernel space with the "kCF" module (Kernel Crypto Framework). Additionally, for Solaris 10, strong crypto algorithms were split off in separate libraries, pkcs11_softtoken_extra libcryptoutil contains low-level utility functions to help implement cryptography. libsoftcrypto (OpenSolaris and Solaris Nevada only) implements several symmetric-key crypto algorithms in software, such as AES, RC4, and DES3, and the bignum library (used for RSA). libmd implements MD5, SHA, and SHA2 message digest algorithms" 4. Difference in T3 and T4 Diagram in this blog is good and self explanatory. Jeff's blog also highlights the differences  "The T4 servers have improved crypto acceleration, described at https://blogs.oracle.com/DanX/entry/sparc_t4_openssl_engine. It is "just built in" so administrators no longer have to assign crypto accelerator units to domains - it "just happens". Every physical or virtual CPU on a SPARC-T4 has full access to hardware based crypto acceleration at all times. .... For completeness sake, it's worth noting that the T4 adds more crypto algorithms, and accelerates Camelia, CRC32c, and more SHA-x." 5. About performance counters In this blog, performance counters are explained : "Note that unlike T3 and before, T4 crypto doesn't require kernel modules like ncp or n2cp, there is no visibility of crypto hardware with kstats or cryptoadm. T4 does provide hardware counters for crypto operations.  You can see these using cpustat: cpustat -c pic0=Instr_FGU_crypto 5 You can check the general crypto support of the hardware and OS with the command "isainfo -v". Since T4 crypto's implementation now allows direct userland access, there are no "crypto units" visible to cryptoadm.  " For more details refer Martin's blog as well. 6. How to turn off  SPARC T4 or Intel AES-NI crypto acceleration  I found this interesting blog from Darren about how to turn off  SPARC T4 or Intel AES-NI crypto acceleration. "One of the new Solaris 11 features of the linker/loader is the ability to have a single ELF object that has multiple different implementations of the same functions that are selected at runtime based on the capabilities of the machine.   The alternate to this is having the application coded to call getisax(2) system call and make the choice itself.  We use this functionality of the linker/loader when we build the userland libraries for the Solaris Cryptographic Framework (specifically libmd.so and libsoftcrypto.so) The Solaris linker/loader allows control of a lot of its functionality via environment variables, we can use that to control the version of the cryptographic functions we run.  To do this we simply export the LD_HWCAP environment variable with values that tell ld.so.1 to not select the HWCAP section matching certain features even if isainfo says they are present.  This will work for consumers of the Solaris Cryptographic Framework that use the Solaris PKCS#11 libraries or use libmd.so interfaces directly.  For SPARC T4 : export LD_HWCAP="-aes -des -md5 -sha256 -sha512 -mont -mpul" .. For Intel systems with AES-NI support: export LD_HWCAP="-aes"" Note that LD_HWCAP is explained in  http://docs.oracle.com/cd/E23823_01/html/816-5165/ld.so.1-1.html "LD_HWCAP, LD_HWCAP_32, and LD_HWCAP_64 -  Identifies an alternative hardware capabilities value... A “-” prefix results in the capabilities that follow being removed from the alternative capabilities." 7. Whitepaper on SPARC T4 Servers—Optimized for End-to-End Data Center Computing This Whitepaper on SPARC T4 Servers—Optimized for End-to-End Data Center Computing explains more details.  It has DTrace scripts which may come in handy : "To ensure the hardware-assisted cryptographic acceleration is configured to use and working with the security scenarios, it is recommended to use the following Solaris DTrace script. #!/usr/sbin/dtrace -s pid$1:libsoftcrypto:yf*:entry, pid$target:libsoftcrypto:rsa*:entry, pid$1:libmd:yf*:entry { @[probefunc] = count(); } tick-1sec { printa(@ops); trunc(@ops); }" Note that I have slightly modified the D Script to have RSA "libsoftcrypto:rsa*:entry" as well as per recommendations from Chi-Chang Lin. 8. References http://www.oracle.com/us/corporate/features/sparc-t4-announcement-494846.html http://www.oracle.com/us/products/servers-storage/servers/sparc-enterprise/t-series/sparc-t4-1-ds-487858.pdf https://blogs.oracle.com/DanX/entry/sparc_t4_openssl_engine https://blogs.oracle.com/DanX/entry/where_s_the_crypto_libraries https://blogs.oracle.com/darren/entry/howto_turn_off_sparc_t4 http://docs.oracle.com/cd/E23823_01/html/816-5165/ld.so.1-1.html   https://blogs.oracle.com/hardware/entry/unleash_the_power_of_cryptography https://blogs.oracle.com/cmt/entry/t4_crypto_cheat_sheet https://blogs.oracle.com/martinm/entry/t4_performance_counters_explained  https://blogs.oracle.com/jsavit/entry/no_mau_required_on_a http://www.oracle.com/us/products/servers-storage/servers/sparc-enterprise/t-series/sparc-t4-business-wp-524472.pdf

    Read the article

  • C# in Depth, Third Edition by Jon Skeet, Manning Publications Co. Book Review

    - by Compudicted
    Originally posted on: http://geekswithblogs.net/Compudicted/archive/2013/10/24/c-in-depth-third-edition-by-jon-skeet-manning-publications.aspx I started reading this ebook on September 28, 2013, the same day it was sent my way by Manning Publications Co. for review while it still being fresh off the press. So 1st thing – thanks to Manning for this opportunity and a free copy of this must have on every C# developer’s desk book! Several hours ago I finished reading this book (well, except a for a large portion of its quite lengthy appendix). I jumped writing this review right away while still being full of emotions and impressions from reading it thoroughly and running code examples. Before I go any further I would like say that I used to program on various platforms using various languages starting with the Mainframe and ending on Windows, and I gradually shifted toward dealing with databases more than anything, however it happened with me to program in C# 1 a lot when it was first released and then some C# 2 with a big leap in between to C# 5. So my perception and experience reading this book may differ from yours. Also what I want to tell is somewhat funny that back then, knowing some Java and seeing C# 1 released, initially made me drawing a parallel that it is a copycat language, how wrong was I… Interestingly, Jon programs in Java full time, but how little it was mentioned in the book! So more on the book: Be informed, this is not a typical “Recipes”, “Cookbook” or any set of ready solutions, it is rather targeting mature, advanced developers who do not only know how to use a number of features, but are willing to understand how the language is operating “under the hood”. I must state immediately, at the same time I am glad the author did not go into the murky depths of the MSIL, so this is a very welcome decision on covering a modern language as C# for me, thank you Jon! Frankly, not all was that rosy regarding the tone and structure of the book, especially the the first half or so filled me with several negative and positive emotions overpowering each other. To expand more on that, some statements in the book appeared to be bias to me, or filled with pre-justice, it started to look like it had some PR-sole in it, but thankfully this was all gone toward the end of the 1st third of the book. Specifically, the mention on the C# language popularity, Java is the #1 language as per https://sites.google.com/site/pydatalog/pypl/PyPL-PopularitY-of-Programming-Language (many other sources put C at the top which I highly doubt), also many interesting functional languages as Clojure and Groovy appeared and gained huge traction which run on top of Java/JVM whereas C# does not enjoy such a situation. If we want to discuss the popularity in general and say how fast a developer can find a new job that pays well it would be indeed the very Java, C++ or PHP, never C#. Or that phrase on language preference as a personal issue? We choose where to work or we are chosen because of a technology used at a given software shop, not vice versa. The book though it technically very accurate with valid code, concise examples, but I wish the author would give more concrete, real-life examples on where each feature should be used, not how. Another point to realize before you get the book is that it is almost a live book which started to be written when even C# 3 wasn’t around so a lot of ground is covered (nearly half of the book) on the pre-C# 3 feature releases so if you already have a solid background in the previous releases and do not plan to upgrade, perhaps half of the book can be skipped, otherwise this book is surely highly recommended. Alas, for me it was a hard read, most of it. It was not boring (well, only may be two times), it was just hard to grasp some concepts, but do not get me wrong, it did made me pause, on several occasions, and made me read and re-read a page or two. At times I even wondered if I have any IQ at all (LOL). Be prepared to read A LOT on generics, not that they are widely used in the field (I happen to work as a consultant and went thru a lot of code at many places) I can tell my impression is the developers today in best case program using examples found at OpenStack.com. Also unlike the Java world where having the most recent version is nearly mandated by the OSS most companies on the Microsoft platform almost never tempted to upgrade the .Net version very soon and very often. As a side note, I was glad to see code recently that included a nullable variable (myvariable? notation) and this made me smile, besides, I recommended that person this book to expand her knowledge. The good things about this book is that Jon maintains an active forum, prepared code snippets and even a small program (Snippy) that is happy to run the sample code saving you from writing any plumbing code. A tad now on the C# language itself – it sure enjoyed a wonderful road toward perfection and a very high adoption, especially for ASP development. But to me all the recent features that made this statically typed language more dynamic look strange. Don’t we have F#? Which supposed to be the dynamic language? Why do we need to have a hybrid language? Now the developers live their lives in dualism of the static and dynamic variables! And LINQ to SQL, it is covered in depth, but wasn’t it supposed to be dropped? Also it seems that very little is being added, and at a slower pace, e.g. Roslyn will come in late 2014 perhaps, and will be probably the only main feature. Again, it is quite hard to read this book as various chapters, C# versions mentioned every so often only if I only could remember what was covered exactly where! So the fact it has so many jumps/links back and forth I recommend the ebook format to make the navigations easier to perform and I do recommend using software that allows bookmarking, also make sure you have access to plenty of coffee and pizza (hey, you probably know this joke – who a programmer is) ! In terms of closing, if you stuck at C# 1 or 2 level, it is time to embrace the power of C# 5! Finally, to compliment Manning, this book unlike from any other publisher so far, was the only one as well readable (put it formatted) on my tablet as in Adobe Reader on a laptop.

    Read the article

  • How to find and fix performance problems in ORM powered applications

    - by FransBouma
    Once in a while we get requests about how to fix performance problems with our framework. As it comes down to following the same steps and looking into the same things every single time, I decided to write a blogpost about it instead, so more people can learn from this and solve performance problems in their O/R mapper powered applications. In some parts it's focused on LLBLGen Pro but it's also usable for other O/R mapping frameworks, as the vast majority of performance problems in O/R mapper powered applications are not specific for a certain O/R mapper framework. Too often, the developer looks at the wrong part of the application, trying to fix what isn't a problem in that part, and getting frustrated that 'things are so slow with <insert your favorite framework X here>'. I'm in the O/R mapper business for a long time now (almost 10 years, full time) and as it's a small world, we O/R mapper developers know almost all tricks to pull off by now: we all know what to do to make task ABC faster and what compromises (because there are almost always compromises) to deal with if we decide to make ABC faster that way. Some O/R mapper frameworks are faster in X, others in Y, but you can be sure the difference is mainly a result of a compromise some developers are willing to deal with and others aren't. That's why the O/R mapper frameworks on the market today are different in many ways, even though they all fetch and save entities from and to a database. I'm not suggesting there's no room for improvement in today's O/R mapper frameworks, there always is, but it's not a matter of 'the slowness of the application is caused by the O/R mapper' anymore. Perhaps query generation can be optimized a bit here, row materialization can be optimized a bit there, but it's mainly coming down to milliseconds. Still worth it if you're a framework developer, but it's not much compared to the time spend inside databases and in user code: if a complete fetch takes 40ms or 50ms (from call to entity object collection), it won't make a difference for your application as that 10ms difference won't be noticed. That's why it's very important to find the real locations of the problems so developers can fix them properly and don't get frustrated because their quest to get a fast, performing application failed. Performance tuning basics and rules Finding and fixing performance problems in any application is a strict procedure with four prescribed steps: isolate, analyze, interpret and fix, in that order. It's key that you don't skip a step nor make assumptions: these steps help you find the reason of a problem which seems to be there, and how to fix it or leave it as-is. Skipping a step, or when you assume things will be bad/slow without doing analysis will lead to the path of premature optimization and won't actually solve your problems, only create new ones. The most important rule of finding and fixing performance problems in software is that you have to understand what 'performance problem' actually means. Most developers will say "when a piece of software / code is slow, you have a performance problem". But is that actually the case? If I write a Linq query which will aggregate, group and sort 5 million rows from several tables to produce a resultset of 10 rows, it might take more than a couple of milliseconds before that resultset is ready to be consumed by other logic. If I solely look at the Linq query, the code consuming the resultset of the 10 rows and then look at the time it takes to complete the whole procedure, it will appear to me to be slow: all that time taken to produce and consume 10 rows? But if you look closer, if you analyze and interpret the situation, you'll see it does a tremendous amount of work, and in that light it might even be extremely fast. With every performance problem you encounter, always do realize that what you're trying to solve is perhaps not a technical problem at all, but a perception problem. The second most important rule you have to understand is based on the old saying "Penny wise, Pound Foolish": the part which takes e.g. 5% of the total time T for a given task isn't worth optimizing if you have another part which takes a much larger part of the total time T for that same given task. Optimizing parts which are relatively insignificant for the total time taken is not going to bring you better results overall, even if you totally optimize that part away. This is the core reason why analysis of the complete set of application parts which participate in a given task is key to being successful in solving performance problems: No analysis -> no problem -> no solution. One warning up front: hunting for performance will always include making compromises. Fast software can be made maintainable, but if you want to squeeze as much performance out of your software, you will inevitably be faced with the dilemma of compromising one or more from the group {readability, maintainability, features} for the extra performance you think you'll gain. It's then up to you to decide whether it's worth it. In almost all cases it's not. The reason for this is simple: the vast majority of performance problems can be solved by implementing the proper algorithms, the ones with proven Big O-characteristics so you know the performance you'll get plus you know the algorithm will work. The time taken by the algorithm implementing code is inevitable: you already implemented the best algorithm. You might find some optimizations on the technical level but in general these are minor. Let's look at the four steps to see how they guide us through the quest to find and fix performance problems. Isolate The first thing you need to do is to isolate the areas in your application which are assumed to be slow. For example, if your application is a web application and a given page is taking several seconds or even minutes to load, it's a good candidate to check out. It's important to start with the isolate step because it allows you to focus on a single code path per area with a clear begin and end and ignore the rest. The rest of the steps are taken per identified problematic area. Keep in mind that isolation focuses on tasks in an application, not code snippets. A task is something that's started in your application by either another task or the user, or another program, and has a beginning and an end. You can see a task as a piece of functionality offered by your application.  Analyze Once you've determined the problem areas, you have to perform analysis on the code paths of each area, to see where the performance problems occur and which areas are not the problem. This is a multi-layered effort: an application which uses an O/R mapper typically consists of multiple parts: there's likely some kind of interface (web, webservice, windows etc.), a part which controls the interface and business logic, the O/R mapper part and the RDBMS, all connected with either a network or inter-process connections provided by the OS or other means. Each of these parts, including the connectivity plumbing, eat up a part of the total time it takes to complete a task, e.g. load a webpage with all orders of a given customer X. To understand which parts participate in the task / area we're investigating and how much they contribute to the total time taken to complete the task, analysis of each participating task is essential. Start with the code you wrote which starts the task, analyze the code and track the path it follows through your application. What does the code do along the way, verify whether it's correct or not. Analyze whether you have implemented the right algorithms in your code for this particular area. Remember we're looking at one area at a time, which means we're ignoring all other code paths, just the code path of the current problematic area, from begin to end and back. Don't dig in and start optimizing at the code level just yet. We're just analyzing. If your analysis reveals big architectural stupidity, it's perhaps a good idea to rethink the architecture at this point. For the rest, we're analyzing which means we collect data about what could be wrong, for each participating part of the complete application. Reviewing the code you wrote is a good tool to get deeper understanding of what is going on for a given task but ultimately it lacks precision and overview what really happens: humans aren't good code interpreters, computers are. We therefore need to utilize tools to get deeper understanding about which parts contribute how much time to the total task, triggered by which other parts and for example how many times are they called. There are two different kind of tools which are necessary: .NET profilers and O/R mapper / RDBMS profilers. .NET profiling .NET profilers (e.g. dotTrace by JetBrains or Ants by Red Gate software) show exactly which pieces of code are called, how many times they're called, and the time it took to run that piece of code, at the method level and sometimes even at the line level. The .NET profilers are essential tools for understanding whether the time taken to complete a given task / area in your application is consumed by .NET code, where exactly in your code, the path to that code, how many times that code was called by other code and thus reveals where hotspots are located: the areas where a solution can be found. Importantly, they also reveal which areas can be left alone: remember our penny wise pound foolish saying: if a profiler reveals that a group of methods are fast, or don't contribute much to the total time taken for a given task, ignore them. Even if the code in them is perhaps complex and looks like a candidate for optimization: you can work all day on that, it won't matter.  As we're focusing on a single area of the application, it's best to start profiling right before you actually activate the task/area. Most .NET profilers support this by starting the application without starting the profiling procedure just yet. You navigate to the particular part which is slow, start profiling in the profiler, in your application you perform the actions which are considered slow, and afterwards you get a snapshot in the profiler. The snapshot contains the data collected by the profiler during the slow action, so most data is produced by code in the area to investigate. This is important, because it allows you to stay focused on a single area. O/R mapper and RDBMS profiling .NET profilers give you a good insight in the .NET side of things, but not in the RDBMS side of the application. As this article is about O/R mapper powered applications, we're also looking at databases, and the software making it possible to consume the database in your application: the O/R mapper. To understand which parts of the O/R mapper and database participate how much to the total time taken for task T, we need different tools. There are two kind of tools focusing on O/R mappers and database performance profiling: O/R mapper profilers and RDBMS profilers. For O/R mapper profilers, you can look at LLBLGen Prof by hibernating rhinos or the Linq to Sql/LLBLGen Pro profiler by Huagati. Hibernating rhinos also have profilers for other O/R mappers like NHibernate (NHProf) and Entity Framework (EFProf) and work the same as LLBLGen Prof. For RDBMS profilers, you have to look whether the RDBMS vendor has a profiler. For example for SQL Server, the profiler is shipped with SQL Server, for Oracle it's build into the RDBMS, however there are also 3rd party tools. Which tool you're using isn't really important, what's important is that you get insight in which queries are executed during the task / area we're currently focused on and how long they took. Here, the O/R mapper profilers have an advantage as they collect the time it took to execute the query from the application's perspective so they also collect the time it took to transport data across the network. This is important because a query which returns a massive resultset or a resultset with large blob/clob/ntext/image fields takes more time to get transported across the network than a small resultset and a database profiler doesn't take this into account most of the time. Another tool to use in this case, which is more low level and not all O/R mappers support it (though LLBLGen Pro and NHibernate as well do) is tracing: most O/R mappers offer some form of tracing or logging system which you can use to collect the SQL generated and executed and often also other activity behind the scenes. While tracing can produce a tremendous amount of data in some cases, it also gives insight in what's going on. Interpret After we've completed the analysis step it's time to look at the data we've collected. We've done code reviews to see whether we've done anything stupid and which parts actually take place and if the proper algorithms have been implemented. We've done .NET profiling to see which parts are choke points and how much time they contribute to the total time taken to complete the task we're investigating. We've performed O/R mapper profiling and RDBMS profiling to see which queries were executed during the task, how many queries were generated and executed and how long they took to complete, including network transportation. All this data reveals two things: which parts are big contributors to the total time taken and which parts are irrelevant. Both aspects are very important. The parts which are irrelevant (i.e. don't contribute significantly to the total time taken) can be ignored from now on, we won't look at them. The parts which contribute a lot to the total time taken are important to look at. We now have to first look at the .NET profiler results, to see whether the time taken is consumed in our own code, in .NET framework code, in the O/R mapper itself or somewhere else. For example if most of the time is consumed by DbCommand.ExecuteReader, the time it took to complete the task is depending on the time the data is fetched from the database. If there was just 1 query executed, according to tracing or O/R mapper profilers / RDBMS profilers, check whether that query is optimal, uses indexes or has to deal with a lot of data. Interpret means that you follow the path from begin to end through the data collected and determine where, along the path, the most time is contributed. It also means that you have to check whether this was expected or is totally unexpected. My previous example of the 10 row resultset of a query which groups millions of rows will likely reveal that a long time is spend inside the database and almost no time is spend in the .NET code, meaning the RDBMS part contributes the most to the total time taken, the rest is compared to that time, irrelevant. Considering the vastness of the source data set, it's expected this will take some time. However, does it need tweaking? Perhaps all possible tweaks are already in place. In the interpret step you then have to decide that further action in this area is necessary or not, based on what the analysis results show: if the analysis results were unexpected and in the area where the most time is contributed to the total time taken is room for improvement, action should be taken. If not, you can only accept the situation and move on. In all cases, document your decision together with the analysis you've done. If you decide that the perceived performance problem is actually expected due to the nature of the task performed, it's essential that in the future when someone else looks at the application and starts asking questions you can answer them properly and new analysis is only necessary if situations changed. Fix After interpreting the analysis results you've concluded that some areas need adjustment. This is the fix step: you're actively correcting the performance problem with proper action targeted at the real cause. In many cases related to O/R mapper powered applications it means you'll use different features of the O/R mapper to achieve the same goal, or apply optimizations at the RDBMS level. It could also mean you apply caching inside your application (compromise memory consumption over performance) to avoid unnecessary re-querying data and re-consuming the results. After applying a change, it's key you re-do the analysis and interpretation steps: compare the results and expectations with what you had before, to see whether your actions had any effect or whether it moved the problem to a different part of the application. Don't fall into the trap to do partly analysis: do the full analysis again: .NET profiling and O/R mapper / RDBMS profiling. It might very well be that the changes you've made make one part faster but another part significantly slower, in such a way that the overall problem hasn't changed at all. Performance tuning is dealing with compromises and making choices: to use one feature over the other, to accept a higher memory footprint, to go away from the strict-OO path and execute queries directly onto the RDBMS, these are choices and compromises which will cross your path if you want to fix performance problems with respect to O/R mappers or data-access and databases in general. In most cases it's not a big issue: alternatives are often good choices too and the compromises aren't that hard to deal with. What is important is that you document why you made a choice, a compromise: which analysis data, which interpretation led you to the choice made. This is key for good maintainability in the years to come. Most common performance problems with O/R mappers Below is an incomplete list of common performance problems related to data-access / O/R mappers / RDBMS code. It will help you with fixing the hotspots you found in the interpretation step. SELECT N+1: (Lazy-loading specific). Lazy loading triggered performance bottlenecks. Consider a list of Orders bound to a grid. You have a Field mapped onto a related field in Order, Customer.CompanyName. Showing this column in the grid will make the grid fetch (indirectly) for each row the Customer row. This means you'll get for the single list not 1 query (for the orders) but 1+(the number of orders shown) queries. To solve this: use eager loading using a prefetch path to fetch the customers with the orders. SELECT N+1 is easy to spot with an O/R mapper profiler or RDBMS profiler: if you see a lot of identical queries executed at once, you have this problem. Prefetch paths using many path nodes or sorting, or limiting. Eager loading problem. Prefetch paths can help with performance, but as 1 query is fetched per node, it can be the number of data fetched in a child node is bigger than you think. Also consider that data in every node is merged on the client within the parent. This is fast, but it also can take some time if you fetch massive amounts of entities. If you keep fetches small, you can use tuning parameters like the ParameterizedPrefetchPathThreshold setting to get more optimal queries. Deep inheritance hierarchies of type Target Per Entity/Type. If you use inheritance of type Target per Entity / Type (each type in the inheritance hierarchy is mapped onto its own table/view), fetches will join subtype- and supertype tables in many cases, which can lead to a lot of performance problems if the hierarchy has many types. With this problem, keep inheritance to a minimum if possible, or switch to a hierarchy of type Target Per Hierarchy, which means all entities in the inheritance hierarchy are mapped onto the same table/view. Of course this has its own set of drawbacks, but it's a compromise you might want to take. Fetching massive amounts of data by fetching large lists of entities. LLBLGen Pro supports paging (and limiting the # of rows returned), which is often key to process through large sets of data. Use paging on the RDBMS if possible (so a query is executed which returns only the rows in the page requested). When using paging in a web application, be sure that you switch server-side paging on on the datasourcecontrol used. In this case, paging on the grid alone is not enough: this can lead to fetching a lot of data which is then loaded into the grid and paged there. Keep note that analyzing queries for paging could lead to the false assumption that paging doesn't occur, e.g. when the query contains a field of type ntext/image/clob/blob and DISTINCT can't be applied while it should have (e.g. due to a join): the datareader will do DISTINCT filtering on the client. this is a little slower but it does perform paging functionality on the data-reader so it won't fetch all rows even if the query suggests it does. Fetch massive amounts of data because blob/clob/ntext/image fields aren't excluded. LLBLGen Pro supports field exclusion for queries. You can exclude fields (also in prefetch paths) per query to avoid fetching all fields of an entity, e.g. when you don't need them for the logic consuming the resultset. Excluding fields can greatly reduce the amount of time spend on data-transport across the network. Use this optimization if you see that there's a big difference between query execution time on the RDBMS and the time reported by the .NET profiler for the ExecuteReader method call. Doing client-side aggregates/scalar calculations by consuming a lot of data. If possible, try to formulate a scalar query or group by query using the projection system or GetScalar functionality of LLBLGen Pro to do data consumption on the RDBMS server. It's far more efficient to process data on the RDBMS server than to first load it all in memory, then traverse the data in-memory to calculate a value. Using .ToList() constructs inside linq queries. It might be you use .ToList() somewhere in a Linq query which makes the query be run partially in-memory. Example: var q = from c in metaData.Customers.ToList() where c.Country=="Norway" select c; This will actually fetch all customers in-memory and do an in-memory filtering, as the linq query is defined on an IEnumerable<T>, and not on the IQueryable<T>. Linq is nice, but it can often be a bit unclear where some parts of a Linq query might run. Fetching all entities to delete into memory first. To delete a set of entities it's rather inefficient to first fetch them all into memory and then delete them one by one. It's more efficient to execute a DELETE FROM ... WHERE query on the database directly to delete the entities in one go. LLBLGen Pro supports this feature, and so do some other O/R mappers. It's not always possible to do this operation in the context of an O/R mapper however: if an O/R mapper relies on a cache, these kind of operations are likely not supported because they make it impossible to track whether an entity is actually removed from the DB and thus can be removed from the cache. Fetching all entities to update with an expression into memory first. Similar to the previous point: it is more efficient to update a set of entities directly with a single UPDATE query using an expression instead of fetching the entities into memory first and then updating the entities in a loop, and afterwards saving them. It might however be a compromise you don't want to take as it is working around the idea of having an object graph in memory which is manipulated and instead makes the code fully aware there's a RDBMS somewhere. Conclusion Performance tuning is almost always about compromises and making choices. It's also about knowing where to look and how the systems in play behave and should behave. The four steps I provided should help you stay focused on the real problem and lead you towards the solution. Knowing how to optimally use the systems participating in your own code (.NET framework, O/R mapper, RDBMS, network/services) is key for success as well as knowing what's going on inside the application you built. I hope you'll find this guide useful in tracking down performance problems and dealing with them in a useful way.  

    Read the article

  • SharePoint 2010 Replaceable Parameter, some observations…

    - by svdoever
    SharePoint Tools for Visual Studio 2010 provides a rudimentary mechanism for replaceable parameters that you can use in files that are not compiled, like ascx files and your project property settings. The basics on this can be found in the documentation at http://msdn.microsoft.com/en-us/library/ee231545.aspx. There are some quirks however. For example: My Package name is MacawMastSP2010Templates, as defined in my Package properties: I want to use the $SharePoint.Package.Name$ replaceable parameter in my feature properties. But this parameter does not work in the “Deployment Path” property, while other parameters work there, while it works in the “Image Url” property. It just does not get expanded. So I had to resort to explicitly naming the first path of the deployment path: : You also see a special property for the “Receiver Class” in the format $SharePoint.Type.<GUID>.FullName$. The documentation gives the following description:The full name of the type matching the GUID in the token. The format of the GUID is lowercase and corresponds to the Guid.ToString(“D”) format (that is, xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx). Not very clear. After some searching it happened to be the guid as declared in my feature receiver code: In other properties you see a different set of replaceable parameters: We use a similar mechanism for replaceable parameter for years in our Macaw Solutions Factory for SharePoint 2007 development, where each replaceable parameter is a PowerShell function. This provides so much more power. For example in a feature declaration we can say: Code Snippet <?xml version="1.0" encoding="utf-8" ?> <!-- Template expansion      [[ProductDependency]] -> Wss3 or Moss2007      [[FeatureReceiverAssemblySignature]] -> for example: Macaw.Mast.Wss3.Templates.SharePoint.Features, Version=1.0.0.0, Culture=neutral, PublicKeyToken=6e9d15db2e2a0be5      [[FeatureReceiverClass]] -> for example: Macaw.Mast.Wss3.Templates.SharePoint.Features.SampleFeature.FeatureReceiver.SampleFeatureFeatureReceiver --> <Feature Id="[[$Feature.SampleFeature.ID]]"   Title="MAST [[$MastSolutionName]] Sample Feature"   Description="The MAST [[$MastSolutionName]] Sample Feature, where all possible elements in a feature are showcased"   Version="1.0.0.0"   Scope="Site"   Hidden="FALSE"   ImageUrl="[[FeatureImage]]"   ReceiverAssembly="[[FeatureReceiverAssemblySignature]]"   ReceiverClass="[[FeatureReceiverClass]]"   xmlns="http://schemas.microsoft.com/sharepoint/">     <ElementManifests>         <ElementManifest Location="ExampleCustomActions.xml" />         <ElementManifest Location="ExampleSiteColumns.xml" />         <ElementManifest Location="ExampleContentTypes.xml" />         <ElementManifest Location="ExampleDocLib.xml" />         <ElementManifest Location="ExampleMasterPages.xml" />           <!-- Element files -->         [[GenerateXmlNodesForFiles -path 'ExampleDocLib\*.*' -node 'ElementFile' -attributes @{Location = { RelativePathToExpansionSourceFile -path $_ }}]]         [[GenerateXmlNodesForFiles -path 'ExampleMasterPages\*.*' -node 'ElementFile' -attributes @{Location = { RelativePathToExpansionSourceFile -path $_ }}]]         [[GenerateXmlNodesForFiles -path 'Resources\*.resx' -node 'ElementFile' -attributes @{Location = { RelativePathToExpansionSourceFile -path $_ }}]]     </ElementManifests> </Feature> We have a solution level PowerShell script file named TemplateExpansionConfiguration.ps1 where we declare our variables (starting with a $) and include helper functions: Code Snippet # ============================================================================================== # NAME: product:\src\Wss3\Templates\TemplateExpansionConfiguration.ps1 # # AUTHOR: Serge van den Oever, Macaw # DATE  : May 24, 2007 # # COMMENT: # Nota bene: define variable and function definitions global to be visible during template expansion. # # ============================================================================================== Set-PSDebug -strict -trace 0 #variables must have value before usage $global:ErrorActionPreference = 'Stop' # Stop on errors $global:VerbosePreference = 'Continue' # set to SilentlyContinue to get no verbose output   # Load template expansion utility functions . product:\tools\Wss3\MastDeploy\TemplateExpansionUtil.ps1   # If exists add solution expansion utility functions $solutionTemplateExpansionUtilFile = $MastSolutionDir + "\TemplateExpansionUtil.ps1" if ((Test-Path -Path $solutionTemplateExpansionUtilFile)) {     . $solutionTemplateExpansionUtilFile } # ==============================================================================================   # Expected: $Solution.ID; Unique GUID value identifying the solution (DON'T INCLUDE BRACKETS). # function: guid:UpperCaseWithoutCurlies -guid '{...}' ensures correct syntax $global:Solution = @{     ID = GuidUpperCaseWithoutCurlies -guid '{d366ced4-0b98-4fa8-b256-c5a35bcbc98b}'; }   #  DON'T INCLUDE BRACKETS for feature id's!!! # function: GuidUpperCaseWithoutCurlies -guid '{...}' ensures correct syntax $global:Feature = @{     SampleFeature = @{         ID = GuidUpperCaseWithoutCurlies -guid '{35de59f4-0c8e-405e-b760-15234fe6885c}';     } }   $global:SiteDefinition = @{     TemplateBlankSite = @{         ID = '12346';     } }   # To inherit from this content type add the delimiter (00) and then your own guid # ID: <base>00<newguid> $global:ContentType = @{     ExampleContentType = @{         ID = '0x01008e5e167ba2db4bfeb3810c4a7ff72913';     } }   #  INCLUDE BRACKETS for column id's and make them LOWER CASE!!! # function: GuidLowerCaseWithCurlies -guid '{...}' ensures correct syntax $global:SiteColumn = @{     ExampleChoiceField = @{         ID = GuidLowerCaseWithCurlies -guid '{69d38ce4-2771-43b4-a861-f14247885fe9}';     };     ExampleBooleanField = @{         ID = GuidLowerCaseWithCurlies -guid '{76f794e6-f7bd-490e-a53e-07efdf967169}';     };     ExampleDateTimeField = @{         ID = GuidLowerCaseWithCurlies -guid '{6f176e6e-22d2-453a-8dad-8ab17ac12387}';     };     ExampleNumberField = @{         ID = GuidLowerCaseWithCurlies -guid '{6026947f-f102-436b-abfd-fece49495788}';     };     ExampleTextField = @{         ID = GuidLowerCaseWithCurlies -guid '{23ca1c29-5ef0-4b3d-93cd-0d1d2b6ddbde}';     };     ExampleUserField = @{         ID = GuidLowerCaseWithCurlies -guid '{ee55b9f1-7b7c-4a7e-9892-3e35729bb1a5}';     };     ExampleNoteField = @{         ID = GuidLowerCaseWithCurlies -guid '{f9aa8da3-1f30-48a6-a0af-aa0a643d9ed4}';     }; } This gives so much more possibilities, like for example the elements file expansion where a PowerShell function iterates through a folder and generates the required XML nodes. I think I will bring back this mechanism, so it can work together with the built-in replaceable parameters, there are hooks to define you custom replacements as described by Waldek in this blog post.

    Read the article

  • Extending NerdDinner: Adding Geolocated Flair

    - by Jon Galloway
    NerdDinner is a website with the audacious goal of “Organizing the world’s nerds and helping them eat in packs.” Because nerds aren’t likely to socialize with others unless a website tells them to do it. Scott Hanselman showed off a lot of the cool features we’ve added to NerdDinner lately during his popular talk at MIX10, Beyond File | New Company: From Cheesy Sample to Social Platform. Did you miss it? Go ahead and watch it, I’ll wait. One of the features we wanted to add was flair. You know about flair, right? It’s a way to let folks who like your site show it off in their own site. For example, here’s my StackOverflow flair: Great! So how could we add some of this flair stuff to NerdDinner? What do we want to show? If we’re going to encourage our users to give up a bit of their beautiful website to show off a bit of ours, we need to think about what they’ll want to show. For instance, my StackOverflow flair is all about me, not StackOverflow. So how will this apply to NerdDinner? Since NerdDinner is all about organizing local dinners, in order for the flair to be useful it needs to make sense for the person viewing the web page. If someone visits from Egypt visits my blog, they should see information about NerdDinners in Egypt. That’s geolocation – localizing site content based on where the browser’s sitting, and it makes sense for flair as well as entire websites. So we’ll set up a simple little callout that prompts them to host a dinner in their area: Hopefully our flair works and there is a dinner near your viewers, so they’ll see another view which lists upcoming dinners near them: The Geolocation Part Generally website geolocation is done by mapping the requestor’s IP address to a geographic area. It’s not an exact science, but I’ve always found it to be pretty accurate. There are (at least) three ways to handle it: You pay somebody like MaxMind for a database (with regular updates) that sits on your server, and you use their API to do lookups. I used this on a pretty big project a few years ago and it worked well. You use HTML 5 Geolocation API or Google Gears or some other browser based solution. I think those are cool (I use Google Gears a lot), but they’re both in flux right now and I don’t think either has a wide enough of an install base yet to rely on them. You might want to, but I’ve heard you do all kinds of crazy stuff, and sometimes it gets you in trouble. I don’t mean talk out of line, but we all laugh behind your back a bit. But, hey, it’s up to you. It’s your flair or whatever. There are some free webservices out there that will take an IP address and give you location information. Easy, and works for everyone. That’s what we’re doing. I looked at a few different services and settled on IPInfoDB. It’s free, has a great API, and even returns JSON, which is handy for Javascript use. The IP query is pretty simple. We hit a URL like this: http://ipinfodb.com/ip_query.php?ip=74.125.45.100&timezone=false … and we get an XML response back like this… <?xml version="1.0" encoding="UTF-8"?> <Response> <Ip>74.125.45.100</Ip> <Status>OK</Status> <CountryCode>US</CountryCode> <CountryName>United States</CountryName> <RegionCode>06</RegionCode> <RegionName>California</RegionName> <City>Mountain View</City> <ZipPostalCode>94043</ZipPostalCode> <Latitude>37.4192</Latitude> <Longitude>-122.057</Longitude> </Response> So we’ll build some data transfer classes to hold the location information, like this: public class LocationInfo { public string Country { get; set; } public string RegionName { get; set; } public string City { get; set; } public string ZipPostalCode { get; set; } public LatLong Position { get; set; } } public class LatLong { public float Lat { get; set; } public float Long { get; set; } } And now hitting the service is pretty simple: public static LocationInfo HostIpToPlaceName(string ip) { string url = "http://ipinfodb.com/ip_query.php?ip={0}&timezone=false"; url = String.Format(url, ip); var result = XDocument.Load(url); var location = (from x in result.Descendants("Response") select new LocationInfo { City = (string)x.Element("City"), RegionName = (string)x.Element("RegionName"), Country = (string)x.Element("CountryName"), ZipPostalCode = (string)x.Element("CountryName"), Position = new LatLong { Lat = (float)x.Element("Latitude"), Long = (float)x.Element("Longitude") } }).First(); return location; } Getting The User’s IP Okay, but first we need the end user’s IP, and you’d think it would be as simple as reading the value from HttpContext: HttpContext.Current.Request.UserHostAddress But you’d be wrong. Sorry. UserHostAddress just wraps HttpContext.Current.Request.ServerVariables["REMOTE_ADDR"], but that doesn’t get you the IP for users behind a proxy. That’s in another header, “HTTP_X_FORWARDED_FOR". So you can either hit a wrapper and then check a header, or just check two headers. I went for uniformity: string SourceIP = string.IsNullOrEmpty(Request.ServerVariables["HTTP_X_FORWARDED_FOR"]) ? Request.ServerVariables["REMOTE_ADDR"] : Request.ServerVariables["HTTP_X_FORWARDED_FOR"]; We’re almost set to wrap this up, but first let’s talk about our views. Yes, views, because we’ll have two. Selecting the View We wanted to make it easy for people to include the flair in their sites, so we looked around at how other people were doing this. The StackOverflow folks have a pretty good flair system, which allows you to include the flair in your site as either an IFRAME reference or a Javascript include. We’ll do both. We have a ServicesController to handle use of the site information outside of NerdDinner.com, so this fits in pretty well there. We’ll be displaying the same information for both HTML and Javascript flair, so we can use one Flair controller action which will return a different view depending on the requested format. Here’s our general flow for our controller action: Get the user’s IP Translate it to a location Grab the top three upcoming dinners that are near that location Select the view based on the format (defaulted to “html”) Return a FlairViewModel which contains the list of dinners and the location information public ActionResult Flair(string format = "html") { string SourceIP = string.IsNullOrEmpty( Request.ServerVariables["HTTP_X_FORWARDED_FOR"]) ? Request.ServerVariables["REMOTE_ADDR"] : Request.ServerVariables["HTTP_X_FORWARDED_FOR"]; var location = GeolocationService.HostIpToPlaceName(SourceIP); var dinners = dinnerRepository. FindByLocation(location.Position.Lat, location.Position.Long). OrderByDescending(p => p.EventDate).Take(3); // Select the view we'll return. // Using a switch because we'll add in JSON and other formats later. string view; switch (format.ToLower()) { case "javascript": view = "JavascriptFlair"; break; default: view = "Flair"; break; } return View( view, new FlairViewModel { Dinners = dinners.ToList(), LocationName = string.IsNullOrEmpty(location.City) ? "you" : String.Format("{0}, {1}", location.City, location.RegionName) } ); } Note: I’m not in love with the logic here, but it seems like overkill to extract the switch statement away when we’ll probably just have two or three views. What do you think? The HTML View The HTML version of the view is pretty simple – the only thing of any real interest here is the use of an extension method to truncate strings that are would cause the titles to wrap. public static string Truncate(this string s, int maxLength) { if (string.IsNullOrEmpty(s) || maxLength <= 0) return string.Empty; else if (s.Length > maxLength) return s.Substring(0, maxLength) + "..."; else return s; }   So here’s how the HTML view ends up looking: <%@ Page Title="" Language="C#" Inherits="System.Web.Mvc.ViewPage<FlairViewModel>" %> <%@ Import Namespace="NerdDinner.Helpers" %> <%@ Import Namespace="NerdDinner.Models" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <title>Nerd Dinner</title> <link href="/Content/Flair.css" rel="stylesheet" type="text/css" /> </head> <body> <div id="nd-wrapper"> <h2 id="nd-header">NerdDinner.com</h2> <div id="nd-outer"> <% if (Model.Dinners.Count == 0) { %> <div id="nd-bummer"> Looks like there's no Nerd Dinners near <%:Model.LocationName %> in the near future. Why not <a target="_blank" href="http://www.nerddinner.com/Dinners/Create">host one</a>?</div> <% } else { %> <h3> Dinners Near You</h3> <ul> <% foreach (var item in Model.Dinners) { %> <li> <%: Html.ActionLink(String.Format("{0} with {1} on {2}", item.Title.Truncate(20), item.HostedBy, item.EventDate.ToShortDateString()), "Details", "Dinners", new { id = item.DinnerID }, new { target = "_blank" })%></li> <% } %> </ul> <% } %> <div id="nd-footer"> More dinners and fun at <a target="_blank" href="http://nrddnr.com">http://nrddnr.com</a></div> </div> </div> </body> </html> You’d include this in a page using an IFRAME, like this: <IFRAME height=230 marginHeight=0 src="http://nerddinner.com/services/flair" frameBorder=0 width=160 marginWidth=0 scrolling=no></IFRAME> The Javascript view The Javascript flair is written so you can include it in a webpage with a simple script include, like this: <script type="text/javascript" src="http://nerddinner.com/services/flair?format=javascript"></script> The goal of this view is very similar to the HTML embed view, with a few exceptions: We’re creating a script element and adding it to the head of the document, which will then document.write out the content. Note that you have to consider if your users will actually have a <head> element in their documents, but for website flair use cases I think that’s a safe bet. Since the content is being added to the existing page rather than shown in an IFRAME, all links need to be absolute. That means we can’t use Html.ActionLink, since it generates relative routes. We need to escape everything since it’s being written out as strings. We need to set the content type to application/x-javascript. The easiest way to do that is to use the <%@ Page ContentType%> directive. <%@ Page Language="C#" Inherits="System.Web.Mvc.ViewPage<NerdDinner.Models.FlairViewModel>" ContentType="application/x-javascript" %> <%@ Import Namespace="NerdDinner.Helpers" %> <%@ Import Namespace="NerdDinner.Models" %> document.write('<script>var link = document.createElement(\"link\");link.href = \"http://nerddinner.com/content/Flair.css\";link.rel = \"stylesheet\";link.type = \"text/css\";var head = document.getElementsByTagName(\"head\")[0];head.appendChild(link);</script>'); document.write('<div id=\"nd-wrapper\"><h2 id=\"nd-header\">NerdDinner.com</h2><div id=\"nd-outer\">'); <% if (Model.Dinners.Count == 0) { %> document.write('<div id=\"nd-bummer\">Looks like there\'s no Nerd Dinners near <%:Model.LocationName %> in the near future. Why not <a target=\"_blank\" href=\"http://www.nerddinner.com/Dinners/Create\">host one</a>?</div>'); <% } else { %> document.write('<h3> Dinners Near You</h3><ul>'); <% foreach (var item in Model.Dinners) { %> document.write('<li><a target=\"_blank\" href=\"http://nrddnr.com/<%: item.DinnerID %>\"><%: item.Title.Truncate(20) %> with <%: item.HostedBy %> on <%: item.EventDate.ToShortDateString() %></a></li>'); <% } %> document.write('</ul>'); <% } %> document.write('<div id=\"nd-footer\"> More dinners and fun at <a target=\"_blank\" href=\"http://nrddnr.com\">http://nrddnr.com</a></div></div></div>'); Getting IP’s for Testing There are a variety of online services that will translate a location to an IP, which were handy for testing these out. I found http://www.itouchmap.com/latlong.html to be most useful, but I’m open to suggestions if you know of something better. Next steps I think the next step here is to minimize load – you know, in case people start actually using this flair. There are two places to think about – the NerdDinner.com servers, and the services we’re using for Geolocation. I usually think about caching as a first attack on server load, but that’s less helpful here since every user will have a different IP. Instead, I’d look at taking advantage of Asynchronous Controller Actions, a cool new feature in ASP.NET MVC 2. Async Actions let you call a potentially long-running webservice without tying up a thread on the server while waiting for the response. There’s some good info on that in the MSDN documentation, and Dino Esposito wrote a great article on Asynchronous ASP.NET Pages in the April 2010 issue of MSDN Magazine. But let’s think of the children, shall we? What about ipinfodb.com? Well, they don’t have specific daily limits, but they do throttle you if you put a lot of traffic on them. From their FAQ: We do not have a specific daily limit but queries that are at a rate faster than 2 per second will be put in "queue". If you stay below 2 queries/second everything will be normal. If you go over the limit, you will still get an answer for all queries but they will be slowed down to about 1 per second. This should not affect most users but for high volume websites, you can either use our IP database on your server or we can whitelist your IP for 5$/month (simply use the donate form and leave a comment with your server IP). Good programming practices such as not querying our API for all page views (you can store the data in a cookie or a database) will also help not reaching the limit. So the first step there is to save the geolocalization information in a time-limited cookie, which will allow us to look up the local dinners immediately without having to hit the geolocation service.

    Read the article

  • Listing common SQL Code Smells.

    - by Phil Factor
    Once you’ve done a number of SQL Code-reviews, you’ll know those signs in the code that all might not be well. These ’Code Smells’ are coding styles that don’t directly cause a bug, but are indicators that all is not well with the code. . Kent Beck and Massimo Arnoldi seem to have coined the phrase in the "OnceAndOnlyOnce" page of www.C2.com, where Kent also said that code "wants to be simple". Bad Smells in Code was an essay by Kent Beck and Martin Fowler, published as Chapter 3 of the book ‘Refactoring: Improving the Design of Existing Code’ (ISBN 978-0201485677) Although there are generic code-smells, SQL has its own particular coding habits that will alert the programmer to the need to re-factor what has been written. See Exploring Smelly Code   and Code Deodorants for Code Smells by Nick Harrison for a grounding in Code Smells in C# I’ve always been tempted by the idea of automating a preliminary code-review for SQL. It would be so useful to trawl through code and pick up the various problems, much like the classic ‘Lint’ did for C, and how the Code Metrics plug-in for .NET Reflector by Jonathan 'Peli' de Halleux is used for finding Code Smells in .NET code. The problem is that few of the standard procedural code smells are relevant to SQL, and we need an agreed list of code smells. Merrilll Aldrich made a grand start last year in his blog Top 10 T-SQL Code Smells.However, I'd like to make a start by discovering if there is a general opinion amongst Database developers what the most important SQL Smells are. One can be a bit defensive about code smells. I will cheerfully write very long stored procedures, even though they are frowned on. I’ll use dynamic SQL occasionally. You can only use them as an aid for your own judgment and it is fine to ‘sign them off’ as being appropriate in particular circumstances. Also, whole classes of ‘code smells’ may be irrelevant for a particular database. The use of proprietary SQL, for example, is only a ‘code smell’ if there is a chance that the database will have to be ported to another RDBMS. The use of dynamic SQL is a risk only with certain security models. As the saying goes,  a CodeSmell is a hint of possible bad practice to a pragmatist, but a sure sign of bad practice to a purist. Plamen Ratchev’s wonderful article Ten Common SQL Programming Mistakes lists some of these ‘code smells’ along with out-and-out mistakes, but there are more. The use of nested transactions, for example, isn’t entirely incorrect, even though the database engine ignores all but the outermost: but it does flag up the possibility that the programmer thinks that nested transactions are supported. If anything requires some sort of general agreement, the definition of code smells is one. I’m therefore going to make this Blog ‘dynamic, in that, if anyone twitters a suggestion with a #SQLCodeSmells tag (or sends me a twitter) I’ll update the list here. If you add a comment to the blog with a suggestion of what should be added or removed, I’ll do my best to oblige. In other words, I’ll try to keep this blog up to date. The name against each 'smell' is the name of the person who Twittered me, commented about or who has written about the 'smell'. it does not imply that they were the first ever to think of the smell! Use of deprecated syntax such as *= (Dave Howard) Denormalisation that requires the shredding of the contents of columns. (Merrill Aldrich) Contrived interfaces Use of deprecated datatypes such as TEXT/NTEXT (Dave Howard) Datatype mis-matches in predicates that rely on implicit conversion.(Plamen Ratchev) Using Correlated subqueries instead of a join   (Dave_Levy/ Plamen Ratchev) The use of Hints in queries, especially NOLOCK (Dave Howard /Mike Reigler) Few or No comments. Use of functions in a WHERE clause. (Anil Das) Overuse of scalar UDFs (Dave Howard, Plamen Ratchev) Excessive ‘overloading’ of routines. The use of Exec xp_cmdShell (Merrill Aldrich) Excessive use of brackets. (Dave Levy) Lack of the use of a semicolon to terminate statements Use of non-SARGable functions on indexed columns in predicates (Plamen Ratchev) Duplicated code, or strikingly similar code. Misuse of SELECT * (Plamen Ratchev) Overuse of Cursors (Everyone. Special mention to Dave Levy & Adrian Hills) Overuse of CLR routines when not necessary (Sam Stange) Same column name in different tables with different datatypes. (Ian Stirk) Use of ‘broken’ functions such as ‘ISNUMERIC’ without additional checks. Excessive use of the WHILE loop (Merrill Aldrich) INSERT ... EXEC (Merrill Aldrich) The use of stored procedures where a view is sufficient (Merrill Aldrich) Not using two-part object names (Merrill Aldrich) Using INSERT INTO without specifying the columns and their order (Merrill Aldrich) Full outer joins even when they are not needed. (Plamen Ratchev) Huge stored procedures (hundreds/thousands of lines). Stored procedures that can produce different columns, or order of columns in their results, depending on the inputs. Code that is never used. Complex and nested conditionals WHILE (not done) loops without an error exit. Variable name same as the Datatype Vague identifiers. Storing complex data  or list in a character map, bitmap or XML field User procedures with sp_ prefix (Aaron Bertrand)Views that reference views that reference views that reference views (Aaron Bertrand) Inappropriate use of sql_variant (Neil Hambly) Errors with identity scope using SCOPE_IDENTITY @@IDENTITY or IDENT_CURRENT (Neil Hambly, Aaron Bertrand) Schemas that involve multiple dated copies of the same table instead of partitions (Matt Whitfield-Atlantis UK) Scalar UDFs that do data lookups (poor man's join) (Matt Whitfield-Atlantis UK) Code that allows SQL Injection (Mladen Prajdic) Tables without clustered indexes (Matt Whitfield-Atlantis UK) Use of "SELECT DISTINCT" to mask a join problem (Nick Harrison) Multiple stored procedures with nearly identical implementation. (Nick Harrison) Excessive column aliasing may point to a problem or it could be a mapping implementation. (Nick Harrison) Joining "too many" tables in a query. (Nick Harrison) Stored procedure returning more than one record set. (Nick Harrison) A NOT LIKE condition (Nick Harrison) excessive "OR" conditions. (Nick Harrison) User procedures with sp_ prefix (Aaron Bertrand) Views that reference views that reference views that reference views (Aaron Bertrand) sp_OACreate or anything related to it (Bill Fellows) Prefixing names with tbl_, vw_, fn_, and usp_ ('tibbling') (Jeremiah Peschka) Aliases that go a,b,c,d,e... (Dave Levy/Diane McNurlan) Overweight Queries (e.g. 4 inner joins, 8 left joins, 4 derived tables, 10 subqueries, 8 clustered GUIDs, 2 UDFs, 6 case statements = 1 query) (Robert L Davis) Order by 3,2 (Dave Levy) MultiStatement Table functions which are then filtered 'Sel * from Udf() where Udf.Col = Something' (Dave Ballantyne) running a SQL 2008 system in SQL 2000 compatibility mode(John Stafford)

    Read the article

  • Customize Team Build 2010 – Part 13: Get control over the Build Output

    In the series the following parts have been published Part 1: Introduction Part 2: Add arguments and variables Part 3: Use more complex arguments Part 4: Create your own activity Part 5: Increase AssemblyVersion Part 6: Use custom type for an argument Part 7: How is the custom assembly found Part 8: Send information to the build log Part 9: Impersonate activities (run under other credentials) Part 10: Include Version Number in the Build Number Part 11: Speed up opening my build process template Part 12: How to debug my custom activities Part 13: Get control over the Build Output Part 14: Execute a PowerShell script Part 15: Fail a build based on the exit code of a console application In the part 8, I have explained how you can add informational messages, warnings or errors to the build output. If you want to integrate with other lines of text to the build output, you need to do more. This post will show you how you can add extra steps, additional information and hyperlinks to the build output. UPDATE 13-12-2010: Thanks to Jason Pricket, it is now also possible to not show every activity in the build log. This is really useful when you are doing for-loops in your template. To see how you can do that, check out Jason's blog: http://blogs.msdn.com/b/jpricket/archive/2010/12/09/tfs-2010-making-your-build-log-less-noisy.aspx Add an hyperlink to the end of the build output Lets start with a simple example of how you can adjust the build output. In this case we are going to add at the end of the build output an hyperlink where a user can click on to for example start the deployment to the test environment. In part 4 you can find information how you can create a custom activity To add information to the build output, you need the BuildDetail. This value is a variable in your xaml and is thus easily transferable to you custom activity. Besides the BuildDetail the user has also to specify the text and the url that has to be added to the end of the build output. The following code segment shows you how you can achieve this.     [BuildActivity(HostEnvironmentOption.All)]    public sealed class AddHyperlinkToBuildOutput : CodeActivity    {        [RequiredArgument]        public InArgument<IBuildDetail> BuildDetail { get; set; }         [RequiredArgument]        public InArgument<string> DisplayText { get; set; }         [RequiredArgument]        public InArgument<string> Url { get; set; }         protected override void Execute(CodeActivityContext context)        {            // Obtain the runtime value of the input arguments                        IBuildDetail buildDetail = context.GetValue(this.BuildDetail);            string displayText = context.GetValue(this.DisplayText);            string url = context.GetValue(this.Url);             // Add the hyperlink            buildDetail.Information.AddExternalLink(displayText, new Uri(url));            buildDetail.Information.Save();        }    } If you add this activity to somewhere in your build process template (within the scope Run on Agent), you will get the following build output Add an line of text to the build output The next challenge is to add this kind of output not only to the end of the build output but at the step that is currently executing. To be able to do this, you need the current node in the build output. The following code shows you how you can achieve this. First you need to get the current activity tracking, which you can get with the following line of code             IActivityTracking currentTracking = context.GetExtension<IBuildLoggingExtension>().GetActivityTracking(context); Then you can create a new node and set its type to Activity Tracking Node (so copy it from the current node) and do nice things with the node.             IBuildInformationNode childNode = currentTracking.Node.Children.CreateNode();            childNode.Type = currentTracking.Node.Type;            childNode.Fields.Add("DisplayText", "This text is displayed."); You can also add a build step to display progress             IBuildStep buildStep = childNode.Children.AddBuildStep("Custom Build Step", "This is my custom build step");            buildStep.FinishTime = DateTime.Now.AddSeconds(10);            buildStep.Status = BuildStepStatus.Succeeded; Or you can add an hyperlink to the node             childNode.Children.AddExternalLink("My link", new Uri(http://www.ewaldhofman.nl)); When you combine this together you get the following result in the build output   You can download the full solution at BuildProcess.zip. It will include the sources of every part and will continue to evolve.

    Read the article

  • Customize Team Build 2010 – Part 13: Get control over the Build Output

    In the series the following parts have been published Part 1: Introduction Part 2: Add arguments and variables Part 3: Use more complex arguments Part 4: Create your own activity Part 5: Increase AssemblyVersion Part 6: Use custom type for an argument Part 7: How is the custom assembly found Part 8: Send information to the build log Part 9: Impersonate activities (run under other credentials) Part 10: Include Version Number in the Build Number Part 11: Speed up opening my build process template Part 12: How to debug my custom activities Part 13: Get control over the Build Output Part 14: Execute a PowerShell script Part 15: Fail a build based on the exit code of a console application     In the part 8, I have explained how you can add informational messages, warnings or errors to the build output. If you want to integrate with other lines of text to the build output, you need to do more. This post will show you how you can add extra steps, additional information and hyperlinks to the build output. Add an hyperlink to the end of the build output Lets start with a simple example of how you can adjust the build output. In this case we are going to add at the end of the build output an hyperlink where a user can click on to for example start the deployment to the test environment. In part 4 you can find information how you can create a custom activity To add information to the build output, you need the BuildDetail. This value is a variable in your xaml and is thus easily transferable to you custom activity. Besides the BuildDetail the user has also to specify the text and the url that has to be added to the end of the build output. The following code segment shows you how you can achieve this.     [BuildActivity(HostEnvironmentOption.All)]    public sealed class AddHyperlinkToBuildOutput : CodeActivity    {        [RequiredArgument]        public InArgument<IBuildDetail> BuildDetail { get; set; }         [RequiredArgument]        public InArgument<string> DisplayText { get; set; }         [RequiredArgument]        public InArgument<string> Url { get; set; }         protected override void Execute(CodeActivityContext context)        {            // Obtain the runtime value of the input arguments                        IBuildDetail buildDetail = context.GetValue(this.BuildDetail);            string displayText = context.GetValue(this.DisplayText);            string url = context.GetValue(this.Url);             // Add the hyperlink            buildDetail.Information.AddExternalLink(displayText, new Uri(url));            buildDetail.Information.Save();        }    } If you add this activity to somewhere in your build process template (within the scope Run on Agent), you will get the following build output Add an line of text to the build output The next challenge is to add this kind of output not only to the end of the build output but at the step that is currently executing. To be able to do this, you need the current node in the build output. The following code shows you how you can achieve this. First you need to get the current activity tracking, which you can get with the following line of code             IActivityTracking currentTracking = context.GetExtension<IBuildLoggingExtension>().GetActivityTracking(context); Then you can create a new node and set its type to Activity Tracking Node (so copy it from the current node) and do nice things with the node.             IBuildInformationNode childNode = currentTracking.Node.Children.CreateNode();            childNode.Type = currentTracking.Node.Type;            childNode.Fields.Add("DisplayText", "This text is displayed."); You can also add a build step to display progress             IBuildStep buildStep = childNode.Children.AddBuildStep("Custom Build Step", "This is my custom build step");            buildStep.FinishTime = DateTime.Now.AddSeconds(10);            buildStep.Status = BuildStepStatus.Succeeded; Or you can add an hyperlink to the node             childNode.Children.AddExternalLink("My link", new Uri(http://www.ewaldhofman.nl)); When you combine this together you get the following result in the build output     You can download the full solution at BuildProcess.zip. It will include the sources of every part and will continue to evolve.

    Read the article

  • Improving the Industry’s Best Cloud Project Portfolio Management (PPM) Solution – New Release of Instantis EnterpriseTrack

    - by Melissa Centurio Lopes
    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-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} By Yasser Mahmud, Vice President of Product Strategy & Industry Marketing, Oracle Primavera We know that in today’s rapidly changing world, organizations and leaders must adapt to fierce competition, business climate change and customers consistently demanding more for less. And project portfolio management (PPM) initiatives are a key component to help organizations thrive and stand out among competitors. That’s why I’m excited to announce Instantis EnterpriseTrack 8.5. Since Oracle’s acquisition of Instantis late last year, we’ve been busy working to enhance the leading cloud PPM solution. 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-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Here’s what’s new: Perform more precise resource planning and management  Gain more precise capacity visibility for resource planning and project execution with resource calendars that capture vacation, LOA and part-time resource availability Ensure compliance and governance processes  with activity labor cost capitalization Improve project labor cost estimation, tracking and administration with variable resource rates 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-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Optimize Project Demand Management And Execution Enhance productivity and analysis with project request flexible staffing plan and simplified finance estimation Improve project status communication and execution with estimated time to complete (ETC) in timesheets and projects Achieve audit compliance and governance with field change history for key project and project request fields Enforce proper financial accounting processes with the new strict finance lock/close period option 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-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} Improve Reporting and the User Experience Enhance user productivity and analysis with improved listing pages Improve program reporting with new program filters in listing pages and reports Run large data volume user defined Excel reports with MS Excel 2010 support Accelerate user productivity and satisfaction with an improved user interface for project issues, risks, and scope changes Enjoy faster system response and improved user experience with  optimized listing pages, resource planning, and application cache Deliver user self-service training on demand with UPK support And if that wasn’t enough, we’ve also made additional improvements to timesheets, field change history and finance lock/close period. Learn more about Instantis EnterpriseTrack 8.5.

    Read the article

  • A pseudo-listener for AlwaysOn Availability Groups for SQL Server virtual machines running in Azure

    - by MikeD
    I am involved in a project that is implementing SharePoint 2013 on virtual machines hosted in Azure. The back end data tier consists of two Azure VMs running SQL Server 2012, with the SharePoint databases contained in an AlwaysOn Availability Group. I used this "Tutorial: AlwaysOn Availability Groups in Windows Azure (GUI)" to help me implement this setup.Because Azure DHCP will not assign multiple unique IP addresses to the same VM, having an AG Listener in Azure is not currently supported.  I wanted to figure out another mechanism to support a "pseudo listener" of some sort. First, I created a CNAME (alias) record in the DNS zone with a short TTL (time to live) of 5 minutes (I may yet make this even shorter). The record represents a logical name (let's say the alias is SPSQL) of the server to connect to for the databases in the availability group (AG). When Server1 was hosting the primary replica of the AG, I would set the CNAME of SPSQL to be SERVER1. When the AG failed over to Server1, I wanted to set the CNAME to SERVER2. Seemed simple enough.(It's important to point out that the connection strings for my SharePoint services should use the CNAME alias, and not the actual server name. This whole thing falls apart otherwise.)To accomplish this, I created identical SQL Agent Jobs on Server1 and Server2, with two steps:1. Step 1: Determine if this server is hosting the primary replica.This is a TSQL step using this script:declare @agName sysname = 'AGTest'set nocount on declare @primaryReplica sysnameselect @primaryReplica = agState.primary_replicafrom sys.dm_hadr_availability_group_states agState   join sys.availability_groups ag on agstate.group_id = ag.group_id   where ag.name = @AGname if not exists(   select *    from sys.dm_hadr_availability_group_states agState   join sys.availability_groups ag on agstate.group_id = ag.group_id   where @@Servername = agstate.primary_replica    and ag.name = @AGname)begin   raiserror ('Primary replica of %s is not hosted on %s, it is hosted on %s',17,1,@Agname, @@Servername, @primaryReplica) endThis script determines if the primary replica value of the AG group is the same as the server name, which means that our server is hosting the current AG (you should update the value of the @AgName variable to the name of your AG). If this is true, I want the DNS alias to point to this server. If the current server is not hosting the primary replica, then the script raises an error. Also, if the script can't be executed because it cannot connect to the server, that also will generate an error. For the job step settings, I set the On Failure option to "Quit the job reporting success". The next step in the job will set the DNS alias to this server name, and I only want to do that if I know that it is the current primary replica, otherwise I don't want to do anything. I also include the step output in the job history so I can see the error message.Job Step 2: Update the CNAME entry in DNS with this server's name.I used a PowerShell script to accomplish this:$cname = "SPSQL.contoso.com"$query = "Select * from MicrosoftDNS_CNAMEType"$dns1 = "dc01.contoso.com"$dns2 = "dc02.contoso.com"if ((Test-Connection -ComputerName $dns1 -Count 1 -Quiet) -eq $true){    $dnsServer = $dns1}elseif ((Test-Connection -ComputerName $dns2 -Count 1 -Quiet) -eq $true) {   $dnsServer = $dns2}else{  $msg = "Unable to connect to DNS servers: " + $dns1 + ", " + $dns2   Throw $msg}$record = Get-WmiObject -Namespace "root\microsoftdns" -Query $query -ComputerName $dnsServer  | ? { $_.Ownername -match $cname }$thisServer = [System.Net.Dns]::GetHostEntry("LocalHost").HostName + "."$currentServer = $record.RecordData if ($currentServer -eq $thisServer ) {     $cname + " CNAME is up to date: " + $currentServer}else{    $cname + " CNAME is being updated to " + $thisServer + ". It was " + $currentServer    $record.RecordData = $thisServer    $record.put()}This script does a few things:finds a responsive domain controller (Test-Connection does a ping and returns a Boolean value if you specify the -Quiet parameter)makes a WMI call to the domain controller to get the current CNAME record value (Get-WmiObject)gets the FQDN of this server (GetHostEntry)checks if the CNAME record is correct and updates it if necessary(You should update the values of the variables $cname, $dns1 and $dns2 for your environment.)Since my domain controllers are also hosted in Azure VMs, either one of them could be down at any point in time, so I need to find a DC that is responsive before attempting the DNS call. The other little thing here is that the CNAME record contains the FQDN of a machine, plus it ends with a period. So the comparison of the CNAME record has to take the trailing period into account. When I tested this step, I was getting ACCESS DENIED responses from PowerShell for the Get-WmiObject cmdlet that does a remote lookup on the DC. This occurred because the SQL Agent service account was not a member of the Domain Admins group, so I decided to create a SQL Credential to store the credentials for a domain administrator account and use it as a PowerShell proxy (rather than give the service account Domain Admins membership).In SQL Management Studio, right click on the Credentials node (under the server's Security node), and choose New Credential...Then, under SQL Agent-->Proxies, right click on the PowerShell node and choose New Proxy...Finally, in the job step properties for the PowerShell step, select the new proxy in the Run As drop down.I created this two step Job on both nodes of the Availability Group, but if you had more than two nodes, just create the same job on all the servers. I set the schedule for the job to execute every minute.When the server that is hosting the primary replica is running the job, the job history looks like this:The job history on the secondary server looks like this: When a failover occurs, the SQL Agent job on the new primary replica will detect that the CNAME needs to be updated within a minute. Based on the TTL of the CNAME (which I said at the beginning was 5 minutes), the SharePoint servers will get the new alias within five minutes and should be able to reconnect. I may want to shorten up the TTL to reduce the time it takes for the client connections to use the new alias. Using a DNS CNAME and a SQL Agent Job on all servers hosting AG replicas, I was able to create a pseudo-listener to automatically change the name of the server that was hosting the primary replica, for a scenario where I cannot use a regular AG listener (in this case, because the servers are all hosted in Azure).    

    Read the article

  • Simple way of converting server side objects into client side using JSON serialization for asp.net websites

    - by anil.kasalanati
     Introduction:- With the growth of Web2.0 and the need for faster user experience the spotlight has shifted onto javascript based applications built using REST pattern or asp.net AJAX Pagerequest manager. And when we are working with javascript wouldn’t it be much better if we could create objects in an OOAD way and easily push it to the client side.  Following are the reasons why you would push the server side objects onto client side -          Easy availability of the complex object. -          Use C# compiler and rick intellisense to create and maintain the objects but use them in the javascript. You could run code analysis etc. -          Reduce the number of calls we make to the server side by loading data on the pageload.   I would like to explain about the 3rd point because that proved to be highly beneficial to me when I was fixing the performance issues of a major website. There could be a scenario where in you be making multiple AJAX based webrequestmanager calls in order to get the same response in a single page. This happens in the case of widget based framework when all the widgets are independent but they need some common information available in the framework to load the data. So instead of making n multiple calls we could load the data needed during pageload. The above picture shows the scenario where in all the widgets need the common information and then call GetData webservice on the server side. Ofcourse the result can be cached on the client side but a better solution would be to avoid the call completely.  In order to do that we need to JSONSerialize the content and send it in the DOM.                                                                                                                                                                                                                                                                                                                                                                                            Example:- I have developed a simple application to demonstrate the idea and I would explaining that in detail here. The class called SimpleClass would be sent as serialized JSON to the client side .   And this inherits from the base class which has the implementation for the GetJSONString method. You can create a single base class and all the object which need to be pushed to the client side can inherit from that class. The important thing to note is that the class should be annotated with DataContract attribute and the methods should have the Data Member attribute. This is needed by the .Net DataContractSerializer and this follows the opt-in mode so if you want to send an attribute to the client side then you need to annotate the DataMember attribute. So if I didn’t want to send the Result I would simple remove the DataMember attribute. This is default WCF/.Net 3.5 stuff but it provides the flexibility of have a fullfledged object on the server side but sending a smaller object to the client side. Sometimes you may hide some values due to security constraints. And thing you will notice is that I have marked the class as Serializable so that it can be stored in the Session and used in webfarm deployment scenarios. Following is the implementation of the base class –  This implements the default DataContractJsonSerializer and for more information or customization refer to following blogs – http://softcero.blogspot.com/2010/03/optimizing-net-json-serializing-and-ii.html http://weblogs.asp.net/gunnarpeipman/archive/2010/12/28/asp-net-serializing-and-deserializing-json-objects.aspx The next part is pretty simple, I just need to inject this object into the aspx page.   And in the aspx markup I have the following line – <script type="text/javascript"> var data =(<%=SimpleClassJSON  %>);   alert(data.ResultText); </script>   This will output the content as JSON into the variable data and this can be any element in the DOM. And you can verify the element by checking data in the Firebug console.    Design Consideration – If you have a lot of javascripts then you need to think about using Script # and you can write javascript in C#. Refer to Nikhil’s blog – http://projects.nikhilk.net/ScriptSharp Ensure that you are taking security into consideration while exposing server side objects on to client side. I have seen application exposing passwords, secret key so it is not a good practice.   The application can be tested using the following url – http://techconsulting.vpscustomer.com/Samples/JsonTest.aspx The source code is available at http://techconsulting.vpscustomer.com/Source/HistoryTest.zip

    Read the article

  • Generate Strongly Typed Observable Events for the Reactive Extensions for .NET (Rx)

    - by Bobby Diaz
    I must have tried reading through the various explanations and introductions to the new Reactive Extensions for .NET before the concepts finally started sinking in.  The article that gave me the ah-ha moment was over on SilverlightShow.net and titled Using Reactive Extensions in Silverlight.  The author did a good job comparing the "normal" way of handling events vs. the new "reactive" methods. Admittedly, I still have more to learn about the Rx Framework, but I wanted to put together a sample project so I could start playing with the new Observable and IObservable<T> constructs.  I decided to throw together a whiteboard application in Silverlight based on the Drawing with Rx example on the aforementioned article.  At the very least, I figured I would learn a thing or two about a new technology, but my real goal is to create a fun application that I can share with the kids since they love drawing and coloring so much! Here is the code sample that I borrowed from the article: var mouseMoveEvent = Observable.FromEvent<MouseEventArgs>(this, "MouseMove"); var mouseLeftButtonDown = Observable.FromEvent<MouseButtonEventArgs>(this, "MouseLeftButtonDown"); var mouseLeftButtonUp = Observable.FromEvent<MouseButtonEventArgs>(this, "MouseLeftButtonUp");       var draggingEvents = from pos in mouseMoveEvent                              .SkipUntil(mouseLeftButtonDown)                              .TakeUntil(mouseLeftButtonUp)                              .Let(mm => mm.Zip(mm.Skip(1), (prev, cur) =>                                  new                                  {                                      X2 = cur.EventArgs.GetPosition(this).X,                                      X1 = prev.EventArgs.GetPosition(this).X,                                      Y2 = cur.EventArgs.GetPosition(this).Y,                                      Y1 = prev.EventArgs.GetPosition(this).Y                                  })).Repeat()                          select pos;       draggingEvents.Subscribe(p =>     {         Line line = new Line();         line.Stroke = new SolidColorBrush(Colors.Black);         line.StrokeEndLineCap = PenLineCap.Round;         line.StrokeLineJoin = PenLineJoin.Round;         line.StrokeThickness = 5;         line.X1 = p.X1;         line.Y1 = p.Y1;         line.X2 = p.X2;         line.Y2 = p.Y2;         this.LayoutRoot.Children.Add(line);     }); One thing that was nagging at the back of my mind was having to deal with the event names as strings, as well as the verbose syntax for the Observable.FromEvent<TEventArgs>() method.  I came up with a couple of static/helper classes to resolve both issues and also created a T4 template to auto-generate these helpers for any .NET type.  Take the following code from the above example: var mouseMoveEvent = Observable.FromEvent<MouseEventArgs>(this, "MouseMove"); var mouseLeftButtonDown = Observable.FromEvent<MouseButtonEventArgs>(this, "MouseLeftButtonDown"); var mouseLeftButtonUp = Observable.FromEvent<MouseButtonEventArgs>(this, "MouseLeftButtonUp"); Turns into this with the new static Events class: var mouseMoveEvent = Events.Mouse.Move.On(this); var mouseLeftButtonDown = Events.Mouse.LeftButtonDown.On(this); var mouseLeftButtonUp = Events.Mouse.LeftButtonUp.On(this); Or better yet, just remove the variable declarations altogether:     var draggingEvents = from pos in Events.Mouse.Move.On(this)                              .SkipUntil(Events.Mouse.LeftButtonDown.On(this))                              .TakeUntil(Events.Mouse.LeftButtonUp.On(this))                              .Let(mm => mm.Zip(mm.Skip(1), (prev, cur) =>                                  new                                  {                                      X2 = cur.EventArgs.GetPosition(this).X,                                      X1 = prev.EventArgs.GetPosition(this).X,                                      Y2 = cur.EventArgs.GetPosition(this).Y,                                      Y1 = prev.EventArgs.GetPosition(this).Y                                  })).Repeat()                          select pos; The Move, LeftButtonDown and LeftButtonUp members of the Events.Mouse class are readonly instances of the ObservableEvent<TTarget, TEventArgs> class that provide type-safe access to the events via the On() method.  Here is the code for the class: using System; using System.Collections.Generic; using System.Linq;   namespace System.Linq {     /// <summary>     /// Represents an event that can be managed via the <see cref="Observable"/> API.     /// </summary>     /// <typeparam name="TTarget">The type of the target.</typeparam>     /// <typeparam name="TEventArgs">The type of the event args.</typeparam>     public class ObservableEvent<TTarget, TEventArgs> where TEventArgs : EventArgs     {         /// <summary>         /// Initializes a new instance of the <see cref="ObservableEvent"/> class.         /// </summary>         /// <param name="eventName">Name of the event.</param>         protected ObservableEvent(String eventName)         {             EventName = eventName;         }           /// <summary>         /// Registers the specified event name.         /// </summary>         /// <param name="eventName">Name of the event.</param>         /// <returns></returns>         public static ObservableEvent<TTarget, TEventArgs> Register(String eventName)         {             return new ObservableEvent<TTarget, TEventArgs>(eventName);         }           /// <summary>         /// Creates an enumerable sequence of event values for the specified target.         /// </summary>         /// <param name="target">The target.</param>         /// <returns></returns>         public IObservable<IEvent<TEventArgs>> On(TTarget target)         {             return Observable.FromEvent<TEventArgs>(target, EventName);         }           /// <summary>         /// Gets or sets the name of the event.         /// </summary>         /// <value>The name of the event.</value>         public string EventName { get; private set; }     } } And this is how it's used:     /// <summary>     /// Categorizes <see cref="ObservableEvents"/> by class and/or functionality.     /// </summary>     public static partial class Events     {         /// <summary>         /// Implements a set of predefined <see cref="ObservableEvent"/>s         /// for the <see cref="System.Windows.System.Windows.UIElement"/> class         /// that represent mouse related events.         /// </summary>         public static partial class Mouse         {             /// <summary>Represents the MouseMove event.</summary>             public static readonly ObservableEvent<UIElement, MouseEventArgs> Move =                 ObservableEvent<UIElement, MouseEventArgs>.Register("MouseMove");               // additional members omitted...         }     } The source code contains a static Events class with prefedined members for various categories (Key, Mouse, etc.).  There is also an Events.tt template that you can customize to generate additional event categories for any .NET type.  All you should have to do is add the name of your class to the types collection near the top of the template:     types = new Dictionary<String, Type>()     {         //{ "Microsoft.Maps.MapControl.Map, Microsoft.Maps.MapControl", null }         { "System.Windows.FrameworkElement, System.Windows", null },         { "Whiteboard.MainPage, Whiteboard", null }     }; The template is also a bit rough at this point, but at least it generates code that *should* compile.  Please let me know if you run into any issues with it.  Some people have reported errors when trying to use T4 templates within a Silverlight project, but I was able to get it to work with a little black magic...  You can download the source code for this project or play around with the live demo.  Just be warned that it is at a very early stage so don't expect to find much today.  I plan on adding alot more options like pen colors and sizes, saving, printing, etc. as time permits.  HINT: hold down the ESC key to erase! Enjoy! Additional Resources Using Reactive Extensions in Silverlight DevLabs: Reactive Extensions for .NET (Rx) Rx Framework Part III - LINQ to Events - Generating GetEventName() Wrapper Methods using T4

    Read the article

  • New OFM versions released SOA Suite 11.1.1.4 &amp; BPM 11.1.1.4 &amp; JDeveloper 11.1.1.4 WebLogic on JRockit 10.3.4 feedback from the community

    - by Jürgen Kress
    Oracle SOA Suite 11g Installations This is the latest release of the Oracle SOA Suite 11g. Please see the Documentation tab for Release Notes, Installation Guides and other release specific information. Please also see the List of New Features and Samples provided for this release. Release 11gR1 (11.1.1.4.0) Microsoft Windows (32-bit JVM) Linux (32-bit JVM) Generic Oracle JDeveloper 11g Rel 1 (11.1.1.x) (JDeveloper + ADF) Integrated development environment certified on Windows, Linux, and Macintosh. License is free (read the Pricing FAQ). Studio Edition for Windows (1.2 GB) | Studio Edition for Linux (1.3 GB) | See All See Additional Development Tools Oracle WebLogic Server 11g Rel 1 (10.3.4) Installers The WebLogic Server installers include Oracle Coherence and Oracle Enterprise Pack for Eclipse and supports development with other Fusion Middleware products . The zip includes WebLogic Server only and is intended for WebLogic Server development only. Linux x86 (1.1 GB) | Windows x86 (1 GB) Zip for Windows x86, Linux x86, Mac OS X (316 MB) | See All Oracle WebLogic Server 11gR1 (10.3.4) on JRockit Virtual Edition Download For additional downloads please visit the Oracle Fusion Middleware Products Update Center Share your feedback with the @soacommunity on twitter SOASimone Simone Geib SOA Suite 11gR1 (11.1.1.4.0) has just been released: http://www.oracle.com/technetwork/middleware/soasuite/downloads/index.html gschmutz gschmutz My new blog post: WebLogic Server, JDev, SOA, BPM, OSB and CEP 11.1.1.4 (PS3) available! - http://tinyurl.com/4negnpn simon_haslam Simon Haslam I'm very pleased to see WLS 10.3.4 for JRockit VE launched at the same time as the rest of PS3 http://j.mp/gl1nQm (32bit anyway) lucasjellema Lucas Jellema See http://www.oracle.com/ocom/groups/public/@otn/documents/webcontent/156082.xml for PS3 extension downloads BPM, SOA Editor, WebCenter demed demed List of new features in @OracleSOA 11gR1 PS3: http://bit.ly/fVRwsP is not extremely long but huge release by # of bugs fixed. Go! biemond Edwin Biemond WebLogic 10.3.4 new features http://bit.ly/f7L1Eu Exalogic Elastic Cloud , JPA2 , Maven plugin, OWSM policies on WebLogic SCA applications JDeveloper JDeveloper & ADF JDeveloper and Oracle ADF 11g Release 1 Patch Set 3 (11.1.1.4.0): New Features and Bug Fixes http://bit.ly/feghnY simon_haslam Simon Haslam WebLogic Server 10.3.4 (i.e. 11gR1 PS3) available now too http://bit.ly/eeysZ2 JDeveloper JDeveloper & ADF Share your impressions on the new JDeveloper 11g Patchset 3 release that came out today! Download it here: http://bit.ly/dogRN8 VikasAatOracle Vikas Anand SOA Suite 11gR1PS3 is Hotpluggable ...see list of features that @Demed posted..#soa #soacommunity   New versions of Oracle Fusion Middleware 11g R1 (11.1.1.4.x)  include: Oracle WebLogic Server 11g R1 (10.3.4) Oracle SOA Suite 11g R1 (11.1.1.4.0) Oracle Business Process Management 11g R1 (11.1.1.4.0) Oracle Complex Event Processing 11g R1 (11.1.1.4.0) Oracle Application Integration Architecture Foundation Pack 11g R1 (11.1.1.4.0) Oracle Service Bus 11g R1 (11.1.1.4.0) Oracle Enterprise Repository 11g R1 (11.1.1.4.0) Oracle Identity Management 11g R1 (11.1.1.4.0) Oracle Enterprise Content Management 11g R1 (11.1.1.4.0) Oracle WebCenter 11g R1 (11.1.1.4.0) - coming soon Oracle Forms, Reports, Portal & Discoverer 11g R1 (11.1.1.4.0) Oracle Repository Creation Utility 11g R1 (11.1.1.4.0) Oracle JDeveloper & Application Development Runtime 11g R1 (11.1.1.4.0) Resources Download  (OTN) Certification Documentation   New Features in Oracle SOA Suite 11g Release 1 (11.1.1.4.0) Updated: January, 2011 Go to Oracle SOA Suite 11g Doc Introduction Oracle SOA Suite 11gR1 (11.1.1.4.0) includes both bug fixes as well as new features listed below - click on the title of each feature for more details. Downloads, documentation links and more information on the Oracle SOA Suite available on the SOA Suite OTN page and as always, we welcome your feedback on the SOA OTN forum. New in Oracle SOA Suite in this release BPEL Component BPEL 2.0 support in JDeveloper The BPEL editor in JDeveloper now generates BPEL 2.0 code and introduces several new activities. Augmented XML variables auto-initialization capabilities The XML variable auto-initialization capabilities have been enhanced to support two need additional use cases: to initialize the to-spec node if it doesn't exist during the rule and to initialize array elements. New Assign Activity dialog The new Assign Activity supports the same drag & drop paradigm used for the XSLT mapper, greatly streamlining the task of assigning multiple variables. Mediator Component Time window parameter for the resequencer This new parameter lets users initiate a best-effort resequencing based on a time window rather than a number of messages. Support for attachments in the Mediator assign dialog The Mediator assign dialog now supports attachment, enabling usage of the Mediator to transmit attachments even if source and target schemas are different. Adapters & Bindings ChunkSize property added to the File Adapter header properties The ChunkSize property of the File Adapter is now available as a header property, allowing in-process modification of the value for this property. Improved support for distributed WLS JMS topics though automatic rebalancing of listeners The JMS Adapter has been enhanced to subscribe to administrative events from WLS JMS. Based on these events, it dynamically rebalances listeners when there are changes to the members of a local or remote WLS JMS distributed destination. JDeveloper configuration wizard for custom JCA adapters A new wizard is available in JDeveloper to configure custom-built adapters Administration & Enterprise Manager Enhanced purging capabilities to manage database growth Historical instance data can now be purged using three different strategies: batch script, scheduled batch script or data partitioning. Asynchronous bulk instance deletion in Enterprise Manager Bulk deletion of instances in Enterprise Manager now executes as an asynchronous operation in Enterprise Manager, returning control to the user as soon as the action has been submitted and acknowledged. B2B Ability to schedule partner downtime This feature allows trading partners to notify each other about planned downtime and to delay delivery of messages during that period. Message sequencing B2B now supports both inbound and outbound message sequencing. Simplified BAM integration with B2B B2B ships with various pre-configured artifacts to simplify monitoring in BAM. Instance Message Java API for B2B The new instance message Java API supports programmatic access to B2B instance message data. Oracle Service Bus (OSB) Certification of the File and FTP JCA Adapters The File and FTP JCA adapters are now certified for use with Oracle Service Bus (in addition to the native transports). Security enhancements Oracle Service Bus now supports SAML 2.0 as well as the OWSM authorization policies. Check the Oracle Service Bus 11.1.1.4 Release Notes for a complete list of new features. Installation, Hot-Pluggability & Certifications Ability to run Oracle SOA Suite on IBM WebSphere Application Server Oracle SOA Suite can now be deployed on IBM WebSphere Application Server Network Deployment (ND) 7.0.11 and IBM WebSphere Application Server 7.0.11. Single JVM developer installation template Oracle SOA Suite can now be targeted to the WebLogic admin server - there is no requirement to also have a managed server. This topology is intended to minimize the memory foorprint of development environments. This is in addition to the list of supported browsers, operating systems and databases already certified in prior releases. Complex Event Processing (CEP) IDE enhancements This release introduces several enhancements to the development IDE, such as adapter wizards and event-type repository. CQL enhancements CQL enhancements include JDBC data cartridges and parametrized queries. Tracing and injecting events in the Event Processing Network (EPN) In the development environment you can now trace and inject events. Check the Oracle CEP 11.1.1.4 Release Notes for a complete list of new features. SOA Suite page on OTN For more information on SOA Specialization and the SOA Partner Community please feel free to register at www.oracle.com/goto/emea/soa (OPN account required) Blog Twitter LinkedIn Mix Forum Wiki Website Technorati Tags: SOA Suite 11.1.1.4,JDeveloper 11.1.1.4,WebLogic 10.3.4,JRockit 10.3.4,SOA Community,Oracle,OPN,SOA,Simone Geib,Guido Schmutz,Edwin Biemond,Lucas Jellema,Simon Haslam,Demed,Vikas Anand,Jürgen Kress

    Read the article

  • Enabling Service Availability in WCF Services

    - by cibrax
    It is very important for the enterprise to know which services are operational at any given point. There are many factors that can affect the availability of the services, some of them are external like a database not responding or any dependant service not working. However, in some cases, you only want to know whether a service is up or down, so a simple heart-beat mechanism with “Ping” messages would do the trick. Unfortunately, WCF does not provide a built-in mechanism to support this functionality, and you probably don’t to implement a “Ping” operation in any service that you have out there. For solving this in a generic way, there is a WCF extensibility point that comes to help us, the “Operation Invokers”. In a nutshell, an operation invoker is the class responsible invoking the service method with a set of parameters and generate the output parameters with the return value. What I am going to do here is to implement a custom operation invoker that intercepts any call to the service, and detects whether a “Ping” header was attached to the message. If the “Ping” header is detected, the operation invoker returns a new header to tell the client that the service is alive, and the real operation execution is omitted. In that way, we have a simple heart beat mechanism based on the messages that include a "Ping” header, so the client application can determine at any point whether the service is up or down. My operation invoker wraps the default implementation attached by default to any operation by WCF. internal class PingOperationInvoker : IOperationInvoker { IOperationInvoker innerInvoker; object[] outputs = null; object returnValue = null; public const string PingHeaderName = "Ping"; public const string PingHeaderNamespace = "http://tellago.serviceModel"; public PingOperationInvoker(IOperationInvoker innerInvoker, OperationDescription description) { this.innerInvoker = innerInvoker; outputs = description.SyncMethod.GetParameters() .Where(p => p.IsOut) .Select(p => DefaultForType(p.ParameterType)).ToArray(); var returnValue = DefaultForType(description.SyncMethod.ReturnType); } private static object DefaultForType(Type targetType) { return targetType.IsValueType ? Activator.CreateInstance(targetType) : null; } public object Invoke(object instance, object[] inputs, out object[] outputs) { object returnValue; if (Invoke(out returnValue, out outputs)) { return returnValue; } else { return this.innerInvoker.Invoke(instance, inputs, out outputs); } } private bool Invoke(out object returnValue, out object[] outputs) { object untypedProperty = null; if (OperationContext.Current .IncomingMessageProperties.TryGetValue(HttpRequestMessageProperty.Name, out untypedProperty)) { var httpRequestProperty = untypedProperty as HttpRequestMessageProperty; if (httpRequestProperty != null) { if (httpRequestProperty.Headers[PingHeaderName] != null) { outputs = this.outputs; if (OperationContext.Current .IncomingMessageProperties.TryGetValue(HttpRequestMessageProperty.Name, out untypedProperty)) { var httpResponseProperty = untypedProperty as HttpResponseMessageProperty; httpResponseProperty.Headers.Add(PingHeaderName, "Ok"); } returnValue = this.returnValue; return true; } } } var headers = OperationContext.Current.IncomingMessageHeaders; if (headers.FindHeader(PingHeaderName, PingHeaderNamespace) > -1) { outputs = this.outputs; MessageHeader<string> header = new MessageHeader<string>("Ok"); var untyped = header.GetUntypedHeader(PingHeaderName, PingHeaderNamespace); OperationContext.Current.OutgoingMessageHeaders.Add(untyped); returnValue = this.returnValue; return true; } returnValue = null; outputs = null; return false; } } The implementation above looks for the “Ping” header either in the Http Request or the Soap message. The next step is to implement a behavior for attaching this operation invoker to the services we want to monitor. [AttributeUsage(AttributeTargets.Method | AttributeTargets.Class, AllowMultiple = false, Inherited = true)] public class PingBehavior : Attribute, IServiceBehavior, IOperationBehavior { public void AddBindingParameters(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase, Collection<ServiceEndpoint> endpoints, BindingParameterCollection bindingParameters) { } public void ApplyDispatchBehavior(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase) { } public void Validate(ServiceDescription serviceDescription, ServiceHostBase serviceHostBase) { foreach (var endpoint in serviceDescription.Endpoints) { foreach (var operation in endpoint.Contract.Operations) { if (operation.Behaviors.Find<PingBehavior>() == null) operation.Behaviors.Add(this); } } } public void AddBindingParameters(OperationDescription operationDescription, BindingParameterCollection bindingParameters) { } public void ApplyClientBehavior(OperationDescription operationDescription, ClientOperation clientOperation) { } public void ApplyDispatchBehavior(OperationDescription operationDescription, DispatchOperation dispatchOperation) { dispatchOperation.Invoker = new PingOperationInvoker(dispatchOperation.Invoker, operationDescription); } public void Validate(OperationDescription operationDescription) { } } As an operation invoker can only be added in an “operation behavior”, a trick I learned in the past is that you can implement a service behavior as well and use the “Validate” method to inject it in all the operations, so the final configuration is much easier and cleaner. You only need to decorate the service with a simple attribute to enable the “Ping” functionality. [PingBehavior] public class HelloWorldService : IHelloWorld { public string Hello(string name) { return "Hello " + name; } } On the other hand, the client application needs to send a dummy message with a “Ping” header to detect whether the service is available or not. In order to simplify this task, I created a extension method in the WCF client channel to do this work. public static class ClientChannelExtensions { const string PingNamespace = "http://tellago.serviceModel"; const string PingName = "Ping"; public static bool IsAvailable<TChannel>(this IClientChannel channel, Action<TChannel> operation) { try { using (OperationContextScope scope = new OperationContextScope(channel)) { MessageHeader<string> header = new MessageHeader<string>(PingName); var untyped = header.GetUntypedHeader(PingName, PingNamespace); OperationContext.Current.OutgoingMessageHeaders.Add(untyped); try { operation((TChannel)channel); var headers = OperationContext.Current.IncomingMessageHeaders; if (headers.Any(h => h.Name == PingName && h.Namespace == PingNamespace)) { return true; } else { return false; } } catch (CommunicationException) { return false; } } } catch (Exception) { return false; } } } This extension method basically adds a “Ping” header to the request message, executes the operation passed as argument (Action<TChannel> operation), and looks for the corresponding “Ping” header in the response to see the results. The client application can use this extension with a single line of code, var client = new ServiceReference.HelloWorldClient(); var isAvailable = client.InnerChannel.IsAvailable<IHelloWorld>((c) => c.Hello(null)); The “isAvailable” variable will tell the client application whether the service is available or not. You can download the complete implementation from this location.    

    Read the article

  • Metro: Introduction to the WinJS ListView Control

    - by Stephen.Walther
    The goal of this blog entry is to provide a quick introduction to the ListView control – just the bare minimum that you need to know to start using the control. When building Metro style applications using JavaScript, the ListView control is the primary control that you use for displaying lists of items. For example, if you are building a product catalog app, then you can use the ListView control to display the list of products. The ListView control supports several advanced features that I plan to discuss in future blog entries. For example, you can group the items in a ListView, you can create master/details views with a ListView, and you can efficiently work with large sets of items with a ListView. In this blog entry, we’ll keep things simple and focus on displaying a list of products. There are three things that you need to do in order to display a list of items with a ListView: Create a data source Create an Item Template Declare the ListView Creating the ListView Data Source The first step is to create (or retrieve) the data that you want to display with the ListView. In most scenarios, you will want to bind a ListView to a WinJS.Binding.List object. The nice thing about the WinJS.Binding.List object is that it enables you to take a standard JavaScript array and convert the array into something that can be bound to the ListView. It doesn’t matter where the JavaScript array comes from. It could be a static array that you declare or you could retrieve the array as the result of an Ajax call to a remote server. The following JavaScript file – named products.js – contains a list of products which can be bound to a ListView. (function () { "use strict"; var products = new WinJS.Binding.List([ { name: "Milk", price: 2.44 }, { name: "Oranges", price: 1.99 }, { name: "Wine", price: 8.55 }, { name: "Apples", price: 2.44 }, { name: "Steak", price: 1.99 }, { name: "Eggs", price: 2.44 }, { name: "Mushrooms", price: 1.99 }, { name: "Yogurt", price: 2.44 }, { name: "Soup", price: 1.99 }, { name: "Cereal", price: 2.44 }, { name: "Pepsi", price: 1.99 } ]); WinJS.Namespace.define("ListViewDemos", { products: products }); })(); The products variable represents a WinJS.Binding.List object. This object is initialized with a plain-old JavaScript array which represents an array of products. To avoid polluting the global namespace, the code above uses the module pattern and exposes the products using a namespace. The list of products is exposed to the world as ListViewDemos.products. To learn more about the module pattern and namespaces in WinJS, see my earlier blog entry: http://stephenwalther.com/blog/archive/2012/02/22/metro-namespaces-and-modules.aspx Creating the ListView Item Template The ListView control does not know how to render anything. It doesn’t know how you want each list item to appear. To get the ListView control to render something useful, you must create an Item Template. Here’s what our template for rendering an individual product looks like: <div id="productTemplate" data-win-control="WinJS.Binding.Template"> <div class="product"> <span data-win-bind="innerText:name"></span> <span data-win-bind="innerText:price"></span> </div> </div> This template displays the product name and price from the data source. Normally, you will declare your template in the same file as you declare the ListView control. In our case, both the template and ListView are declared in the default.html file. To learn more about templates, see my earlier blog entry: http://stephenwalther.com/blog/archive/2012/02/27/metro-using-templates.aspx Declaring the ListView The final step is to declare the ListView control in a page. Here’s the markup for declaring a ListView: <div data-win-control="WinJS.UI.ListView" data-win-options="{ itemDataSource:ListViewDemos.products.dataSource, itemTemplate:select('#productTemplate') }"> </div> You declare a ListView by adding the data-win-control to an HTML DIV tag. The data-win-options attribute is used to set two properties of the ListView. The ListView is associated with its data source with the itemDataSource property. Notice that the data source is ListViewDemos.products.dataSource and not just ListViewDemos.products. You need to associate the ListView with the dataSoure property. The ListView is associated with its item template with the help of the itemTemplate property. The ID of the item template — #productTemplate – is used to select the template from the page. Here’s what the complete version of the default.html page looks like: <!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>ListViewDemos</title> <!-- WinJS references --> <link href="//Microsoft.WinJS.0.6/css/ui-dark.css" rel="stylesheet"> <script src="//Microsoft.WinJS.0.6/js/base.js"></script> <script src="//Microsoft.WinJS.0.6/js/ui.js"></script> <!-- ListViewDemos references --> <link href="/css/default.css" rel="stylesheet"> <script src="/js/default.js"></script> <script src="/js/products.js" type="text/javascript"></script> <style type="text/css"> .product { width: 200px; height: 100px; border: white solid 1px; } </style> </head> <body> <div id="productTemplate" data-win-control="WinJS.Binding.Template"> <div class="product"> <span data-win-bind="innerText:name"></span> <span data-win-bind="innerText:price"></span> </div> </div> <div data-win-control="WinJS.UI.ListView" data-win-options="{ itemDataSource:ListViewDemos.products.dataSource, itemTemplate:select('#productTemplate') }"> </div> </body> </html> Notice that the page above includes a reference to the products.js file: <script src=”/js/products.js” type=”text/javascript”></script> The page above also contains a Template control which contains the ListView item template. Finally, the page includes the declaration of the ListView control. Summary The goal of this blog entry was to describe the minimal set of steps which you must complete to use the WinJS ListView control to display a simple list of items. You learned how to create a data source, declare an item template, and declare a ListView control.

    Read the article

  • Master Data Management and Cloud Computing

    - by david.butler(at)oracle.com
    Cloud Computing is all the rage these days. There are many reasons why this is so. But like its predecessor, Service Oriented Architecture, it can fall on hard times if the underlying data is left unmanaged. Master Data Management is the perfect Cloud companion. It can materially increase the chances for successful Cloud initiatives. In this blog, I'll review the nature of the Cloud and show how MDM fits in.   Here's the National Institute of Standards and Technology Cloud definition: •          Cloud computing is a model for enabling convenient, on-demand network access to a shared pool of configurable computing resources that can be rapidly provisioned and released with minimal management effort or service provider interaction.   Cloud architectures have three main layers: applications or Software as a Service (SaaS), Platforms as a Service (PaaS), and Infrastructure as a Service (IaaS). SaaS generally refers to applications that are delivered to end-users over the Internet. Oracle CRM On Demand is an example of a SaaS application. Today there are hundreds of SaaS providers covering a wide variety of applications including Salesforce.com, Workday, and Netsuite. Oracle MDM applications are located in this layer of Oracle's On Demand enterprise Cloud platform. We call it Master Data as a Service (MDaaS). PaaS generally refers to an application deployment platform delivered as a service. They are often built on a grid computing architecture and include database and middleware. Oracle Fusion Middleware is in this category and includes the SOA and Data Integration products used to connect SaaS applications including MDM. Finally, IaaS generally refers to computing hardware (servers, storage and network) delivered as a service.  This typically includes the associated software as well: operating systems, virtualization, clustering, etc.    Cloud Computing benefits are compelling for a large number of organizations. These include significant cost savings, increased flexibility, and fast deployments. Cost advantages include paying for just what you use. This is especially critical for organizations with variable or seasonal usage. Companies don't have to invest to support peak computing periods. Costs are also more predictable and controllable. Increased agility includes access to the latest technology and experts without making significant up front investments.   While Cloud Computing is certainly very alluring with a clear value proposition, it is not without its challenges. An IDC survey of 244 IT executives/CIOs and their line-of-business (LOB) colleagues identified a number of issues:   Security - 74% identified security as an issue involving data privacy and resource access control. Integration - 61% found that it is hard to integrate Cloud Apps with in-house applications. Operational Costs - 50% are worried that On Demand will actually cost more given the impact of poor data quality on the rest of the enterprise. Compliance - 49% felt that compliance with required regulatory, legal and general industry requirements (such as PCI, HIPAA and Sarbanes-Oxley) would be a major issue. When control is lost, the ability of a provider to directly manage how and where data is deployed, used and destroyed is negatively impacted.  There are others, but I singled out these four top issues because Master Data Management, properly incorporated into a Cloud Computing infrastructure, can significantly ameliorate all of these problems. Cloud Computing can literally rain raw data across the enterprise.   According to fellow blogger, Mike Ferguson, "the fracturing of data caused by the adoption of cloud computing raises the importance of MDM in keeping disparate data synchronized."   David Linthicum, CTO Blue Mountain Labs blogs that "the lack of MDM will become more of an issue as cloud computing rises. We're moving from complex federated on-premise systems, to complex federated on-premise and cloud-delivered systems."    Left unmanaged, non-standard, inconsistent, ungoverned data with questionable quality can pollute analytical systems, increase operational costs, and reduce the ROI in Cloud and On-Premise applications. As cloud computing becomes more relevant, and more data, applications, services, and processes are moved out to cloud computing platforms, the need for MDM becomes ever more important. Oracle's MDM suite is designed to deal with all four of the above Cloud issues listed in the IDC survey.   Security - MDM manages all master data attribute privacy and resource access control issues. Integration - MDM pre-integrates Cloud Apps with each other and with On Premise applications at the data level. Operational Costs - MDM significantly reduces operational costs by increasing data quality, thereby improving enterprise business processes efficiency. Compliance - MDM, with its built in Data Governance capabilities, insures that the data is governed according to organizational standards. This facilitates rapid and accurate reporting for compliance purposes. Oracle MDM creates governed high quality master data. A unified cleansed and standardized data view is produced. The Oracle Customer Hub creates a single view of the customer. The Oracle Product Hub creates high quality product data designed to support all go-to-market processes. Oracle Supplier Hub dramatically reduces the chances of 'supplier exceptions'. Oracle Site Hub masters locations. And Oracle Hyperion Data Relationship Management masters financial reference data and manages enterprise hierarchies across operational areas from ERP to EPM and CRM to SCM. Oracle Fusion Middleware connects Cloud and On Premise applications to MDM Hubs and brings high quality master data to your enterprise business processes.   An independent analyst once said "Poor data quality is like dirt on the windshield. You may be able to drive for a long time with slowly degrading vision, but at some point, you either have to stop and clear the windshield or risk everything."  Cloud Computing has the potential to significantly degrade data quality across the enterprise over time. Deploying a Master Data Management solution prior to or in conjunction with a move to the Cloud can insure that the data flowing into the enterprise from the Cloud is clean and governed. This will in turn insure that expected returns on the investment in Cloud Computing will be realized.       Oracle MDM has proven its metal in this area and has the customers to back that up. In fact, I will be hosting a webcast on Tuesday, April 10th at 10 am PT with one of our top Cloud customers, the Church Pension Group. They have moved all mainline applications to a hosted model and use Oracle MDM to insure the master data is managed and cleansed before it is propagated to other cloud and internal systems. I invite you join Martin Hossfeld, VP, IT Operations, and Danette Patterson, Enterprise Data Manager as they review business drivers for MDM and hosted applications, how they did it, the benefits achieved, and lessons learned. You can register for this free webcast here.  Hope to see you there.

    Read the article

  • Parallel LINQ - PLINQ

    - by nmarun
    Turns out now with .net 4.0 we can run a query like a multi-threaded application. Say you want to query a collection of objects and return only those that meet certain conditions. Until now, we basically had one ‘control’ that iterated over all the objects in the collection, checked the condition on each object and returned if it passed. We obviously agree that if we can ‘break’ this task into smaller ones, assign each task to a different ‘control’ and ask all the controls to do their job - in-parallel, the time taken the finish the entire task will be much lower. Welcome to PLINQ. Let’s take some examples. I have the following method that uses our good ol’ LINQ. 1: private static void Linq(int lowerLimit, int upperLimit) 2: { 3: // populate an array with int values from lowerLimit to the upperLimit 4: var source = Enumerable.Range(lowerLimit, upperLimit); 5:  6: // Start a timer 7: Stopwatch stopwatch = new Stopwatch(); 8: stopwatch.Start(); 9:  10: // set the expectation => build the expression tree 11: var evenNumbers =   from num in source 12: where IsDivisibleBy(num, 2) 13: select num; 14: 15: // iterate over and print the returned items 16: foreach (var number in evenNumbers) 17: { 18: Console.WriteLine(string.Format("** {0}", number)); 19: } 20:  21: stopwatch.Stop(); 22:  23: // check the metrics 24: Console.WriteLine(String.Format("Elapsed {0}ms", stopwatch.ElapsedMilliseconds)); 25: } I’ve added comments for the major steps, but the only thing I want to talk about here is the IsDivisibleBy() method. I know I could have just included the logic directly in the where clause. I called a method to add ‘delay’ to the execution of the query - to simulate a loooooooooong operation (will be easier to compare the results). 1: private static bool IsDivisibleBy(int number, int divisor) 2: { 3: // iterate over some database query 4: // to add time to the execution of this method; 5: // the TableB has around 10 records 6: for (int i = 0; i < 10; i++) 7: { 8: DataClasses1DataContext dataContext = new DataClasses1DataContext(); 9: var query = from b in dataContext.TableBs select b; 10: 11: foreach (var row in query) 12: { 13: // Do NOTHING (wish my job was like this) 14: } 15: } 16:  17: return number % divisor == 0; 18: } Now, let’s look at how to modify this to PLINQ. 1: private static void Plinq(int lowerLimit, int upperLimit) 2: { 3: // populate an array with int values from lowerLimit to the upperLimit 4: var source = Enumerable.Range(lowerLimit, upperLimit); 5:  6: // Start a timer 7: Stopwatch stopwatch = new Stopwatch(); 8: stopwatch.Start(); 9:  10: // set the expectation => build the expression tree 11: var evenNumbers = from num in source.AsParallel() 12: where IsDivisibleBy(num, 2) 13: select num; 14:  15: // iterate over and print the returned items 16: foreach (var number in evenNumbers) 17: { 18: Console.WriteLine(string.Format("** {0}", number)); 19: } 20:  21: stopwatch.Stop(); 22:  23: // check the metrics 24: Console.WriteLine(String.Format("Elapsed {0}ms", stopwatch.ElapsedMilliseconds)); 25: } That’s it, this is now in PLINQ format. Oh and if you haven’t found the difference, look line 11 a little more closely. You’ll see an extension method ‘AsParallel()’ added to the ‘source’ variable. Couldn’t be more simpler right? So this is going to improve the performance for us. Let’s test it. So in my Main method of the Console application that I’m working on, I make a call to both. 1: static void Main(string[] args) 2: { 3: // set lower and upper limits 4: int lowerLimit = 1; 5: int upperLimit = 20; 6: // call the methods 7: Console.WriteLine("Calling Linq() method"); 8: Linq(lowerLimit, upperLimit); 9: 10: Console.WriteLine(); 11: Console.WriteLine("Calling Plinq() method"); 12: Plinq(lowerLimit, upperLimit); 13:  14: Console.ReadLine(); // just so I get enough time to read the output 15: } YMMV, but here are the results that I got:    It’s quite obvious from the above results that the Plinq() method is taking considerably less time than the Linq() version. I’m sure you’ve already noticed that the output of the Plinq() method is not in order. That’s because, each of the ‘control’s we sent to fetch the results, reported with values as and when they obtained them. This is something about parallel LINQ that one needs to remember – the collection cannot be guaranteed to be undisturbed. This could be counted as a negative about PLINQ (emphasize ‘could’). Nevertheless, if we want the collection to be sorted, we can use a SortedSet (.net 4.0) or build our own custom ‘sorter’. Either way we go, there’s a good chance we’ll end up with a better performance using PLINQ. And there’s another negative of PLINQ (depending on how you see it). This is regarding the CPU cycles. See the usage for Linq() method (used ResourceMonitor): I have dual CPU’s and see the height of the peak in the bottom two blocks and now compare to what happens when I run the Plinq() method. The difference is obvious. Higher usage, but for a shorter duration (width of the peak). Both these points make sense in both cases. Linq() runs for a longer time, but uses less resources whereas Plinq() runs for a shorter time and consumes more resources. Even after knowing all these, I’m still inclined towards PLINQ. PLINQ rocks! (no hard feelings LINQ)

    Read the article

  • Conversion of BizTalk Projects to Use the New WCF-SAP Adaptor

    - by Geordie
    We are in the process of upgrading our BizTalk Environment from BizTalk 2006 R2 to BizTalk 2010. The SAP adaptor in BizTalk 2010 is an all new and more powerful WCF-SAP adaptor. When my colleagues tested out the new adaptor they discovered that the format of the data extracted from SAP was not identical to the old adaptor. This is not a big deal if the structure of the messages from SAP is simple. In this case we were receiving the delivery and invoice iDocs. Both these structures are complex especially the delivery document. Over the past few years I have tweaked the delivery mapping to remove bugs from original mapping. The idea of redoing these maps did not appeal and due to the current work load was not even an option. I opted for a rather crude alternative of pulling in the iDoc in the new typed format and then adding a static map at the start of the orchestration to convert the data to the old schema.  Note WCF-SAP data formats (on the binding tab of the configuration dialog box is the ‘RecieiveIdocFormat’ field): Typed:  Returns a XML document with the hierarchy represented in XML and all fields being represented by XML tags. RFC: Returns an XML document with the hierarchy represented in XML but the iDoc lines in flat file format. String: This returns the iDoc in a format that is closest to the original flat file format but is still wrapped with some top level XML tags. The files also contained some strange characters at the end of each line. I started with the invoice document and it was quite straight forward to add the mapping but this is where my problems started. The orchestrations for these documents are dynamic and so require the identity of the partner to be able to correctly configure the orchestration. The partner identity is in the EDI_DC40 segment of the iDoc. In the old project the RECPRN node of the segment was promoted. The code to set a variable to the partner ID was now failing. After lot of head scratching I discovered the problem was due to the addition of Namespaces to the fields in the EDI_DC40 segment. To overcome this I needed to use an xPath query with a Namespace Manager. This had to be done in custom code. I now tried to repeat the process with the delivery document. Unfortunately when we tried to get sample typed data from SAP an exception was thrown. The adapter "WCF-SAP" raised an error message. Details "Microsoft.ServiceModel.Channels.Common.XmlReaderGenerationException: The segment or group definition E2EDKA1001 was not found in the IDoc metadata. The UniqueId of the IDoc type is: IDOCTYP/3/DESADV01/ZASNEXT1/640. For Receive operations, the SAP adapter does not support unreleased segments.   Our guess is that when the WCF-SAP adaptor tries to down load the data it retrieves a data schema from SAP. For some reason the schema does not match the data. This may be due to the version of SAP we are running or due to a customization. Either way resolving this problem did not look easy. When doing some research on this problem I found an article showing me how to get the data from SAP using the WCF-SAP adaptor without any XML tags. http://blogs.msdn.com/b/adapters/archive/2007/10/05/receiving-idocs-getting-the-raw-idoc-data.aspx Reproduction of Mustansir blog: Since the WCF based SAP Adapter is ... well, WCF based, all data flowing in and out of the adapter is encapsulated within a SOAP message. Which means there are those pesky xml tags all over the place. If you want to receive an Idoc from SAP, you can receive it in "Typed" format (in which case each column in each segment of the idoc appears within its own xml tag), or you can receive it in "String" format (in which case there are just 2 xml tags at the top, the raw xml data in string/flat file format, and the 2 closing xml tags). In "String" format, an incoming idoc (for ORDERS05, containing 5 data records) would look like: <ReceiveIdoc ><idocData>EDI_DC40 8000000000001064985620 E2EDK01005 800000000000106498500000100000001 E2EDK14 8000000000001064985000002000000020111000 E2EDK14 8000000000001064985000003000000020081000 E2EDK14 80000000000010649850000040000000200710 E2EDK14 80000000000010649850000050000000200600</idocData></ReceiveIdoc> (I have trimmed part of the control record so that it fits cleanly here on one line). Now, you're only interested in the IDOC data, and don't care much for the XML tags. It isn't that difficult to write your own pipeline component, or even some logic in the orchestration to remove the tags, right? Well, you don't need to write any extra code at all - the WCF Adapter can help you here! During the configuration of your one-way Receive Location using WCF-Custom, navigate to the Messages tab. Under the section "Inbound BizTalk Messge Body", select the "Path" radio button, and: (a) Enter the body path expression as: /*[local-name()='ReceiveIdoc']/*[local-name()='idocData'] (b) Choose "String" for the Node Encoding. What we've done is, used an XPATH to pull out the value of the "idocData" node from the XML. Your Receive Location will now emit text containing only the idoc data. You can at this point, for example, put the Flat File Pipeline component to convert the flat text into a different xml format based on some other schema you already have, and receive your version of the xml formatted message in your orchestration.   This was potentially a much easier solution than adding the static maps to the orchestrations and overcame the issue with ‘Typed’ delivery documents. Not quite so fast… Note: When I followed Mustansir’s blog the characters at the end of each line disappeared. After configuring the adaptor and passing the iDoc data into the original flat file receive pipelines I was receiving exceptions. There was a failure executing the receive pipeline: "PAPINETPipelines.DeliveryFlatFileReceive, CustomerIntegration2.PAPINET.Pipelines, Version=1.0.0.0, Culture=neutral, PublicKeyToken=4ca3635fbf092bbb" Source: "Pipeline " Receive Port: "recSAP_Delivery" URI: "D:\CustomerIntegration2\SAP\Delivery\*.xml" Reason: An error occurred when parsing the incoming document: "Unexpected data found while looking for: 'Z2EDPZ7' The current definition being parsed is E2EDP07GRP. The stream offset where the error occured is 8859. The line number where the error occured is 23. The column where the error occured is 0.". Although the new flat file looked the same as the old one there was a differences. In the original file all lines in the document were exactly 1064 character long. In the new file all lines were truncated to the last alphanumeric character. The final piece of the puzzle was to add a custom pipeline component to pad all the lines to 1064 characters. This component was added to the decode node of the custom delivery and invoice flat file disassembler pipelines. Execute method of the custom pipeline component: public IBaseMessage Execute(IPipelineContext pc, IBaseMessage inmsg) { //Convert Stream to a string Stream s = null; IBaseMessagePart bodyPart = inmsg.BodyPart;   // NOTE inmsg.BodyPart.Data is implemented only as a setter in the http adapter API and a //getter and setter for the file adapter. Use GetOriginalDataStream to get data instead. if (bodyPart != null) s = bodyPart.GetOriginalDataStream();   string newMsg = string.Empty; string strLine; try { StreamReader sr = new StreamReader(s); strLine = sr.ReadLine(); while (strLine != null) { //Execute padding code if (strLine != null) strLine = strLine.PadRight(1064, ' ') + "\r\n"; newMsg += strLine; strLine = sr.ReadLine(); } sr.Close(); } catch (IOException ex) { throw new Exception("Error occured trying to pad the message to 1064 charactors"); }   //Convert back to stream and set to Data property inmsg.BodyPart.Data = new MemoryStream(Encoding.UTF8.GetBytes(newMsg)); ; //reset the position of the stream to zero inmsg.BodyPart.Data.Position = 0; return inmsg; }

    Read the article

  • C#/.NET Little Wonders: Using &lsquo;default&rsquo; to Get Default Values

    - 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 help improve your code by making it easier to write and maintain. The index of all my past little wonders posts can be found here. Today’s little wonder is another of those small items that can help a lot in certain situations, especially when writing generics.  In particular, it is useful in determining what the default value of a given type would be. The Problem: what’s the default value for a generic type? There comes a time when you’re writing generic code where you may want to set an item of a given generic type.  Seems simple enough, right?  We’ll let’s see! Let’s say we want to query a Dictionary<TKey, TValue> for a given key and get back the value, but if the key doesn’t exist, we’d like a default value instead of throwing an exception. So, for example, we might have a the following dictionary defined: 1: var lookup = new Dictionary<int, string> 2: { 3: { 1, "Apple" }, 4: { 2, "Orange" }, 5: { 3, "Banana" }, 6: { 4, "Pear" }, 7: { 9, "Peach" } 8: }; And using those definitions, perhaps we want to do something like this: 1: // assume a default 2: string value = "Unknown"; 3:  4: // if the item exists in dictionary, get its value 5: if (lookup.ContainsKey(5)) 6: { 7: value = lookup[5]; 8: } But that’s inefficient, because then we’re double-hashing (once for ContainsKey() and once for the indexer).  Well, to avoid the double-hashing, we could use TryGetValue() instead: 1: string value; 2:  3: // if key exists, value will be put in value, if not default it 4: if (!lookup.TryGetValue(5, out value)) 5: { 6: value = "Unknown"; 7: } But the “flow” of using of TryGetValue() can get clunky at times when you just want to assign either the value or a default to a variable.  Essentially it’s 3-ish lines (depending on formatting) for 1 assignment.  So perhaps instead we’d like to write an extension method to support a cleaner interface that will return a default if the item isn’t found: 1: public static class DictionaryExtensions 2: { 3: public static TValue GetValueOrDefault<TKey, TValue>(this Dictionary<TKey, TValue> dict, 4: TKey key, TValue defaultIfNotFound) 5: { 6: TValue value; 7:  8: // value will be the result or the default for TValue 9: if (!dict.TryGetValue(key, out value)) 10: { 11: value = defaultIfNotFound; 12: } 13:  14: return value; 15: } 16: } 17:  So this creates an extension method on Dictionary<TKey, TValue> that will attempt to get a value using the given key, and will return the defaultIfNotFound as a stand-in if the key does not exist. This code compiles, fine, but what if we would like to go one step further and allow them to specify a default if not found, or accept the default for the type?  Obviously, we could overload the method to take the default or not, but that would be duplicated code and a bit heavy for just specifying a default.  It seems reasonable that we could set the not found value to be either the default for the type, or the specified value. So what if we defaulted the type to null? 1: public static TValue GetValueOrDefault<TKey, TValue>(this Dictionary<TKey, TValue> dict, 2: TKey key, TValue defaultIfNotFound = null) // ... No, this won’t work, because only reference types (and Nullable<T> wrapped types due to syntactical sugar) can be assigned to null.  So what about a calling parameterless constructor? 1: public static TValue GetValueOrDefault<TKey, TValue>(this Dictionary<TKey, TValue> dict, 2: TKey key, TValue defaultIfNotFound = new TValue()) // ... No, this won’t work either for several reasons.  First, we’d expect a reference type to return null, not an “empty” instance.  Secondly, not all reference types have a parameter-less constructor (string for example does not).  And finally, a constructor cannot be determined at compile-time, while default values can. The Solution: default(T) – returns the default value for type T Many of us know the default keyword for its uses in switch statements as the default case.  But it has another use as well: it can return us the default value for a given type.  And since it generates the same defaults that default field initialization uses, it can be determined at compile-time as well. For example: 1: var x = default(int); // x is 0 2:  3: var y = default(bool); // y is false 4:  5: var z = default(string); // z is null 6:  7: var t = default(TimeSpan); // t is a TimeSpan with Ticks == 0 8:  9: var n = default(int?); // n is a Nullable<int> with HasValue == false Notice that for numeric types the default is 0, and for reference types the default is null.  In addition, for struct types, the value is a default-constructed struct – which simply means a struct where every field has their default value (hence 0 Ticks for TimeSpan, etc.). So using this, we could modify our code to this: 1: public static class DictionaryExtensions 2: { 3: public static TValue GetValueOrDefault<TKey, TValue>(this Dictionary<TKey, TValue> dict, 4: TKey key, TValue defaultIfNotFound = default(TValue)) 5: { 6: TValue value; 7:  8: // value will be the result or the default for TValue 9: if (!dict.TryGetValue(key, out value)) 10: { 11: value = defaultIfNotFound; 12: } 13:  14: return value; 15: } 16: } Now, if defaultIfNotFound is unspecified, it will use default(TValue) which will be the default value for whatever value type the dictionary holds.  So let’s consider how we could use this: 1: lookup.GetValueOrDefault(1); // returns “Apple” 2:  3: lookup.GetValueOrDefault(5); // returns null 4:  5: lookup.GetValueOrDefault(5, “Unknown”); // returns “Unknown” 6:  Again, do not confuse a parameter-less constructor with the default value for a type.  Remember that the default value for any type is the compile-time default for any instance of that type (0 for numeric, false for bool, null for reference types, and struct will all default fields for struct).  Consider the difference: 1: // both zero 2: int i1 = default(int); 3: int i2 = new int(); 4:  5: // both “zeroed” structs 6: var dt1 = default(DateTime); 7: var dt2 = new DateTime(); 8:  9: // sb1 is null, sb2 is an “empty” string builder 10: var sb1 = default(StringBuilder()); 11: var sb2 = new StringBuilder(); So in the above code, notice that the value types all resolve the same whether using default or parameter-less construction.  This is because a value type is never null (even Nullable<T> wrapped types are never “null” in a reference sense), they will just by default contain fields with all default values. However, for reference types, the default is null and not a constructed instance.  Also it should be noted that not all classes have parameter-less constructors (string, for instance, doesn’t have one – and doesn’t need one). Summary Whenever you need to get the default value for a type, especially a generic type, consider using the default keyword.  This handy word will give you the default value for the given type at compile-time, which can then be used for initialization, optional parameters, etc. Technorati Tags: C#,CSharp,.NET,Little Wonders,default

    Read the article

  • CI Deployment Of Azure Web Roles Using TeamCity

    - by srkirkland
    After recently migrating an important new website to use Windows Azure “Web Roles” I wanted an easier way to deploy new versions to the Azure Staging environment as well as a reliable process to rollback deployments to a certain “known good” source control commit checkpoint.  By configuring our JetBrains’ TeamCity CI server to utilize Windows Azure PowerShell cmdlets to create new automated deployments, I’ll show you how to take control of your Azure publish process. Step 0: Configuring your Azure Project in Visual Studio Before we can start looking at automating the deployment, we should make sure manual deployments from Visual Studio are working properly.  Detailed information for setting up deployments can be found at http://msdn.microsoft.com/en-us/library/windowsazure/ff683672.aspx#PublishAzure or by doing some quick Googling, but the basics are as follows: Install the prerequisite Windows Azure SDK Create an Azure project by right-clicking on your web project and choosing “Add Windows Azure Cloud Service Project” (or by manually adding that project type) Configure your Role and Service Configuration/Definition as desired Right-click on your azure project and choose “Publish,” create a publish profile, and push to your web role You don’t actually have to do step #4 and create a publish profile, but it’s a good exercise to make sure everything is working properly.  Once your Windows Azure project is setup correctly, we are ready to move on to understanding the Azure Publish process. Understanding the Azure Publish Process The actual Windows Azure project is fairly simple at its core—it builds your dependent roles (in our case, a web role) against a specific service and build configuration, and outputs two files: ServiceConfiguration.Cloud.cscfg: This is just the file containing your package configuration info, for example Instance Count, OsFamily, ConnectionString and other Setting information. ProjectName.Azure.cspkg: This is the package file that contains the guts of your deployment, including all deployable files. When you package your Azure project, these two files will be created within the directory ./[ProjectName].Azure/bin/[ConfigName]/app.publish/.  If you want to build your Azure Project from the command line, it’s as simple as calling MSBuild on the “Publish” target: msbuild.exe /target:Publish Windows Azure PowerShell Cmdlets The last pieces of the puzzle that make CI automation possible are the Azure PowerShell Cmdlets (http://msdn.microsoft.com/en-us/library/windowsazure/jj156055.aspx).  These cmdlets are what will let us create deployments without Visual Studio or other user intervention. Preparing TeamCity for Azure Deployments Now we are ready to get our TeamCity server setup so it can build and deploy Windows Azure projects, which we now know requires the Azure SDK and the Windows Azure PowerShell Cmdlets. Installing the Azure SDK is easy enough, just go to https://www.windowsazure.com/en-us/develop/net/ and click “Install” Once this SDK is installed, I recommend running a test build to make sure your project is building correctly.  You’ll want to setup your build step using MSBuild with the “Publish” target against your solution file.  Mine looks like this: Assuming the build was successful, you will now have the two *.cspkg and *cscfg files within your build directory.  If the build was red (failed), take a look at the build logs and keep an eye out for “unsupported project type” or other build errors, which will need to be addressed before the CI deployment can be completed. With a successful build we are now ready to install and configure the Windows Azure PowerShell Cmdlets: Follow the instructions at http://msdn.microsoft.com/en-us/library/windowsazure/jj554332 to install the Cmdlets and configure PowerShell After installing the Cmdlets, you’ll need to get your Azure Subscription Info using the Get-AzurePublishSettingsFile command. Store the resulting *.publishsettings file somewhere you can get to easily, like C:\TeamCity, because you will need to reference it later from your deploy script. Scripting the CI Deploy Process Now that the cmdlets are installed on our TeamCity server, we are ready to script the actual deployment using a TeamCity “PowerShell” build runner.  Before we look at any code, here’s a breakdown of our deployment algorithm: Setup your variables, including the location of the *.cspkg and *cscfg files produced in the earlier MSBuild step (remember, the folder is something like [ProjectName].Azure/bin/[ConfigName]/app.publish/ Import the Windows Azure PowerShell Cmdlets Import and set your Azure Subscription information (this is basically your authentication/authorization step, so protect your settings file Now look for a current deployment, and if you find one Upgrade it, else Create a new deployment Pretty simple and straightforward.  Now let’s look at the code (also available as a gist here: https://gist.github.com/3694398): $subscription = "[Your Subscription Name]" $service = "[Your Azure Service Name]" $slot = "staging" #staging or production $package = "[ProjectName]\bin\[BuildConfigName]\app.publish\[ProjectName].cspkg" $configuration = "[ProjectName]\bin\[BuildConfigName]\app.publish\ServiceConfiguration.Cloud.cscfg" $timeStampFormat = "g" $deploymentLabel = "ContinuousDeploy to $service v%build.number%"   Write-Output "Running Azure Imports" Import-Module "C:\Program Files (x86)\Microsoft SDKs\Windows Azure\PowerShell\Azure\*.psd1" Import-AzurePublishSettingsFile "C:\TeamCity\[PSFileName].publishsettings" Set-AzureSubscription -CurrentStorageAccount $service -SubscriptionName $subscription   function Publish(){ $deployment = Get-AzureDeployment -ServiceName $service -Slot $slot -ErrorVariable a -ErrorAction silentlycontinue   if ($a[0] -ne $null) { Write-Output "$(Get-Date -f $timeStampFormat) - No deployment is detected. Creating a new deployment. " } if ($deployment.Name -ne $null) { #Update deployment inplace (usually faster, cheaper, won't destroy VIP) Write-Output "$(Get-Date -f $timeStampFormat) - Deployment exists in $servicename. Upgrading deployment." UpgradeDeployment } else { CreateNewDeployment } }   function CreateNewDeployment() { write-progress -id 3 -activity "Creating New Deployment" -Status "In progress" Write-Output "$(Get-Date -f $timeStampFormat) - Creating New Deployment: In progress"   $opstat = New-AzureDeployment -Slot $slot -Package $package -Configuration $configuration -label $deploymentLabel -ServiceName $service   $completeDeployment = Get-AzureDeployment -ServiceName $service -Slot $slot $completeDeploymentID = $completeDeployment.deploymentid   write-progress -id 3 -activity "Creating New Deployment" -completed -Status "Complete" Write-Output "$(Get-Date -f $timeStampFormat) - Creating New Deployment: Complete, Deployment ID: $completeDeploymentID" }   function UpgradeDeployment() { write-progress -id 3 -activity "Upgrading Deployment" -Status "In progress" Write-Output "$(Get-Date -f $timeStampFormat) - Upgrading Deployment: In progress"   # perform Update-Deployment $setdeployment = Set-AzureDeployment -Upgrade -Slot $slot -Package $package -Configuration $configuration -label $deploymentLabel -ServiceName $service -Force   $completeDeployment = Get-AzureDeployment -ServiceName $service -Slot $slot $completeDeploymentID = $completeDeployment.deploymentid   write-progress -id 3 -activity "Upgrading Deployment" -completed -Status "Complete" Write-Output "$(Get-Date -f $timeStampFormat) - Upgrading Deployment: Complete, Deployment ID: $completeDeploymentID" }   Write-Output "Create Azure Deployment" Publish   Creating the TeamCity Build Step The only thing left is to create a second build step, after your MSBuild “Publish” step, with the build runner type “PowerShell”.  Then set your script to “Source Code,” the script execution mode to “Put script into PowerShell stdin with “-Command” arguments” and then copy/paste in the above script (replacing the placeholder sections with your values).  This should look like the following:   Wrap Up After combining the MSBuild /target:Publish step (which creates the necessary Windows Azure *.cspkg and *.cscfg files) and a PowerShell script step which utilizes the Azure PowerShell Cmdlets, we have a fully deployable build configuration in TeamCity.  You can configure this step to run whenever you’d like using build triggers – for example, you could even deploy whenever a new master branch deploy comes in and passes all required tests. In the script I’ve hardcoded that every deployment goes to the Staging environment on Azure, but you could deploy straight to Production if you want to, or even setup a deployment configuration variable and set it as desired. After your TeamCity Build Configuration is complete, you’ll see something that looks like this: Whenever you click the “Run” button, all of your code will be compiled, published, and deployed to Windows Azure! One additional enormous benefit of automating the process this way is that you can easily deploy any specific source control changeset by clicking the little ellipsis button next to "Run.”  This will bring up a dialog like the one below, where you can select the last change to use for your deployment.  Since Azure Web Role deployments don’t have any rollback functionality, this is a critical feature.   Enjoy!

    Read the article

< Previous Page | 512 513 514 515 516 517 518 519 520 521 522 523  | Next Page >