mcs/class/System.Web.Mvc3/Mvc/HttpHandlerUtil.cs

   1 namespace System.Web.Mvc {
   2     using System;
   3     using System.Diagnostics.CodeAnalysis;
   4     using System.Web;
   5     using System.Web.Mvc.Resources;
   6     using System.Web.UI;
   7
   8     internal static class HttpHandlerUtil {
   9
  10         // Since Server.Execute() doesn't propagate HttpExceptions where the status code is
  11         // anything other than 500, we need to wrap these exceptions ourselves.
  12         [SuppressMessage("Microsoft.Reliability", "CA2000:Dispose objects before losing scope", Justification = "The Dispose on Page doesn't do anything by default, and we control both of these internal types.")]
  13         public static IHttpHandler WrapForServerExecute(IHttpHandler httpHandler) {
  14             IHttpAsyncHandler asyncHandler = httpHandler as IHttpAsyncHandler;
  15             return (asyncHandler != null) ? new ServerExecuteHttpHandlerAsyncWrapper(asyncHandler) : new ServerExecuteHttpHandlerWrapper(httpHandler);
  16         }
  17
  18         // Server.Execute() requires that the provided IHttpHandler subclass Page.
  19         internal class ServerExecuteHttpHandlerWrapper : Page {
  20             private readonly IHttpHandler _httpHandler;
  21
  22             public ServerExecuteHttpHandlerWrapper(IHttpHandler httpHandler) {
  23                 _httpHandler = httpHandler;
  24             }
  25
  26             internal IHttpHandler InnerHandler {
  27                 get {
  28                     return _httpHandler;
  29                 }
  30             }
  31
  32             public override void ProcessRequest(HttpContext context) {
  33                 Wrap(() => _httpHandler.ProcessRequest(context));
  34             }
  35
  36             protected static void Wrap(Action action) {
  37                 Wrap(delegate {
  38                     action();
  39                     return (object)null;
  40                 });
  41             }
  42
  43             protected static TResult Wrap<TResult>(Func<TResult> func) {
  44                 try {
  45                     return func();
  46                 }
  47                 catch (HttpException he) {
  48                     if (he.GetHttpCode() == 500) {
  49                         throw; // doesn't need to be wrapped
  50                     }
  51                     else {
  52                         HttpException newHe = new HttpException(500, MvcResources.ViewPageHttpHandlerWrapper_ExceptionOccurred, he);
  53                         throw newHe;
  54                     }
  55                 }
  56             }
  57         }
  58
  59         private sealed class ServerExecuteHttpHandlerAsyncWrapper : ServerExecuteHttpHandlerWrapper, IHttpAsyncHandler {
  60             private readonly IHttpAsyncHandler _httpHandler;
  61
  62             public ServerExecuteHttpHandlerAsyncWrapper(IHttpAsyncHandler httpHandler)
  63                 : base(httpHandler) {
  64                 _httpHandler = httpHandler;
  65             }
  66
  67             public IAsyncResult BeginProcessRequest(HttpContext context, AsyncCallback cb, object extraData) {
  68                 return Wrap(() => _httpHandler.BeginProcessRequest(context, cb, extraData));
  69             }
  70
  71             public void EndProcessRequest(IAsyncResult result) {
  72                 Wrap(() => _httpHandler.EndProcessRequest(result));
  73             }
  74         }
  75
  76     }
  77 }