mcs/class/System.Web.Mvc2/System.Web.Mvc/MvcHandler.cs

   1 /* ****************************************************************************\r
   2  *\r
   3  * Copyright (c) Microsoft Corporation. All rights reserved.\r
   4  *\r
   5  * This software is subject to the Microsoft Public License (Ms-PL). \r
   6  * A copy of the license can be found in the license.htm file included \r
   7  * in this distribution.\r
   8  *\r
   9  * You must not remove this notice, or any other, from this software.\r
  10  *\r
  11  * ***************************************************************************/\r
  12 \r
  13 namespace System.Web.Mvc {\r
  14     using System;\r
  15     using System.Diagnostics.CodeAnalysis;\r
  16     using System.Globalization;\r
  17     using System.Linq;\r
  18     using System.Reflection;\r
  19     using System.Threading;\r
  20     using System.Web;\r
  21     using System.Web.Mvc.Async;\r
  22     using System.Web.Mvc.Resources;\r
  23     using System.Web.Routing;\r
  24     using System.Web.SessionState;\r
  25 \r
  26     [SuppressMessage("Microsoft.Security", "CA2112:SecuredTypesShouldNotExposeFields", Justification = "There's nothing secret about the value of this field.")]\r
  27     public class MvcHandler : IHttpAsyncHandler, IHttpHandler, IRequiresSessionState {\r
  28         private static readonly object _processRequestTag = new object();\r
  29         private ControllerBuilder _controllerBuilder;\r
  30 \r
  31         internal static readonly string MvcVersion = GetMvcVersionString();\r
  32         public static readonly string MvcVersionHeaderName = "X-AspNetMvc-Version";\r
  33 \r
  34         public MvcHandler(RequestContext requestContext) {\r
  35             if (requestContext == null) {\r
  36                 throw new ArgumentNullException("requestContext");\r
  37             }\r
  38 \r
  39             RequestContext = requestContext;\r
  40         }\r
  41 \r
  42         internal ControllerBuilder ControllerBuilder {\r
  43             get {\r
  44                 if (_controllerBuilder == null) {\r
  45                     _controllerBuilder = ControllerBuilder.Current;\r
  46                 }\r
  47                 return _controllerBuilder;\r
  48             }\r
  49             set {\r
  50                 _controllerBuilder = value;\r
  51             }\r
  52         }\r
  53 \r
  54         public static bool DisableMvcResponseHeader {\r
  55             get;\r
  56             set;\r
  57         }\r
  58 \r
  59         protected virtual bool IsReusable {\r
  60             get {\r
  61                 return false;\r
  62             }\r
  63         }\r
  64 \r
  65         public RequestContext RequestContext {\r
  66             get;\r
  67             private set;\r
  68         }\r
  69 \r
  70         protected internal virtual void AddVersionHeader(HttpContextBase httpContext) {\r
  71             if (!DisableMvcResponseHeader) {\r
  72                 httpContext.Response.AppendHeader(MvcVersionHeaderName, MvcVersion);\r
  73             }\r
  74         }\r
  75 \r
  76         protected virtual IAsyncResult BeginProcessRequest(HttpContext httpContext, AsyncCallback callback, object state) {\r
  77             HttpContextBase iHttpContext = new HttpContextWrapper(httpContext);\r
  78             return BeginProcessRequest(iHttpContext, callback, state);\r
  79         }\r
  80 \r
  81         protected internal virtual IAsyncResult BeginProcessRequest(HttpContextBase httpContext, AsyncCallback callback, object state) {\r
  82             IController controller;\r
  83             IControllerFactory factory;\r
  84             ProcessRequestInit(httpContext, out controller, out factory);\r
  85 \r
  86             IAsyncController asyncController = controller as IAsyncController;\r
  87             if (asyncController != null) {\r
  88                 // asynchronous controller\r
  89                 BeginInvokeDelegate beginDelegate = delegate(AsyncCallback asyncCallback, object asyncState) {\r
  90                     try {\r
  91                         return asyncController.BeginExecute(RequestContext, asyncCallback, asyncState);\r
  92                     }\r
  93                     catch {\r
  94                         factory.ReleaseController(asyncController);\r
  95                         throw;\r
  96                     }\r
  97                 };\r
  98 \r
  99                 EndInvokeDelegate endDelegate = delegate(IAsyncResult asyncResult) {\r
 100                     try {\r
 101                         asyncController.EndExecute(asyncResult);\r
 102                     }\r
 103                     finally {\r
 104                         factory.ReleaseController(asyncController);\r
 105                     }\r
 106                 };\r
 107 \r
 108                 SynchronizationContext syncContext = SynchronizationContextUtil.GetSynchronizationContext();\r
 109                 AsyncCallback newCallback = AsyncUtil.WrapCallbackForSynchronizedExecution(callback, syncContext);\r
 110                 return AsyncResultWrapper.Begin(newCallback, state, beginDelegate, endDelegate, _processRequestTag);\r
 111             }\r
 112             else {\r
 113                 // synchronous controller\r
 114                 Action action = delegate {\r
 115                     try {\r
 116                         controller.Execute(RequestContext);\r
 117                     }\r
 118                     finally {\r
 119                         factory.ReleaseController(controller);\r
 120                     }\r
 121                 };\r
 122 \r
 123                 return AsyncResultWrapper.BeginSynchronous(callback, state, action, _processRequestTag);\r
 124             }\r
 125         }\r
 126 \r
 127         protected internal virtual void EndProcessRequest(IAsyncResult asyncResult) {\r
 128             AsyncResultWrapper.End(asyncResult, _processRequestTag);\r
 129         }\r
 130 \r
 131         private static string GetMvcVersionString() {\r
 132             // DevDiv 216459:\r
 133             // This code originally used Assembly.GetName(), but that requires FileIOPermission, which isn't granted in\r
 134             // medium trust. However, Assembly.FullName *is* accessible in medium trust.\r
 135             return new AssemblyName(typeof(MvcHandler).Assembly.FullName).Version.ToString(2);\r
 136         }\r
 137 \r
 138         protected virtual void ProcessRequest(HttpContext httpContext) {\r
 139             HttpContextBase iHttpContext = new HttpContextWrapper(httpContext);\r
 140             ProcessRequest(iHttpContext);\r
 141         }\r
 142 \r
 143         protected internal virtual void ProcessRequest(HttpContextBase httpContext) {\r
 144             IController controller;\r
 145             IControllerFactory factory;\r
 146             ProcessRequestInit(httpContext, out controller, out factory);\r
 147 \r
 148             try {\r
 149                 controller.Execute(RequestContext);\r
 150             }\r
 151             finally {\r
 152                 factory.ReleaseController(controller);\r
 153             }\r
 154         }\r
 155 \r
 156         private void ProcessRequestInit(HttpContextBase httpContext, out IController controller, out IControllerFactory factory) {\r
 157             AddVersionHeader(httpContext);\r
 158             RemoveOptionalRoutingParameters();\r
 159 \r
 160             // Get the controller type\r
 161             string controllerName = RequestContext.RouteData.GetRequiredString("controller");\r
 162 \r
 163             // Instantiate the controller and call Execute\r
 164             factory = ControllerBuilder.GetControllerFactory();\r
 165             controller = factory.CreateController(RequestContext, controllerName);\r
 166             if (controller == null) {\r
 167                 throw new InvalidOperationException(\r
 168                     String.Format(\r
 169                         CultureInfo.CurrentUICulture,\r
 170                         MvcResources.ControllerBuilder_FactoryReturnedNull,\r
 171                         factory.GetType(),\r
 172                         controllerName));\r
 173             }\r
 174         }\r
 175 \r
 176         private void RemoveOptionalRoutingParameters() {\r
 177             RouteValueDictionary rvd = RequestContext.RouteData.Values;\r
 178 \r
 179             // Get all keys for which the corresponding value is 'Optional'.\r
 180             // ToArray() necessary so that we don't manipulate the dictionary while enumerating.\r
 181             string[] matchingKeys = (from entry in rvd\r
 182                                      where entry.Value == UrlParameter.Optional\r
 183                                      select entry.Key).ToArray();\r
 184 \r
 185             foreach (string key in matchingKeys) {\r
 186                 rvd.Remove(key);\r
 187             }\r
 188         }\r
 189 \r
 190         #region IHttpHandler Members\r
 191         bool IHttpHandler.IsReusable {\r
 192             get {\r
 193                 return IsReusable;\r
 194             }\r
 195         }\r
 196 \r
 197         void IHttpHandler.ProcessRequest(HttpContext httpContext) {\r
 198             ProcessRequest(httpContext);\r
 199         }\r
 200         #endregion\r
 201 \r
 202         #region IHttpAsyncHandler Members\r
 203         IAsyncResult IHttpAsyncHandler.BeginProcessRequest(HttpContext context, AsyncCallback cb, object extraData) {\r
 204             return BeginProcessRequest(context, cb, extraData);\r
 205         }\r
 206 \r
 207         void IHttpAsyncHandler.EndProcessRequest(IAsyncResult result) {\r
 208             EndProcessRequest(result);\r
 209         }\r
 210         #endregion\r
 211     }\r
 212 }\r