mcs/class/System.Web/System.Web/HttpApplicationFactory.cs

   1 // \r
   2 // System.Web.HttpApplicationFactory\r
   3 //\r
   4 // Author:\r
   5 //      Patrik Torstensson (ptorsten@hotmail.com)\r
   6 //      Gonzalo Paniagua Javier (gonzalo@ximian.com)\r
   7 //\r
   8 // (c) 2002,2003 Ximian, Inc. (http://www.ximian.com)\r
   9 //\r
  10
  11 //
  12 // Permission is hereby granted, free of charge, to any person obtaining
  13 // a copy of this software and associated documentation files (the
  14 // "Software"), to deal in the Software without restriction, including
  15 // without limitation the rights to use, copy, modify, merge, publish,
  16 // distribute, sublicense, and/or sell copies of the Software, and to
  17 // permit persons to whom the Software is furnished to do so, subject to
  18 // the following conditions:
  19 //
  20 // The above copyright notice and this permission notice shall be
  21 // included in all copies or substantial portions of the Software.
  22 //
  23 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  27 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  28 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  29 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  30 //
  31 using System;\r
  32 using System.Collections;\r
  33 using System.IO;\r
  34 using System.Reflection;\r
  35 using System.Web.UI;\r
  36 using System.Web.Compilation;\r
  37 using System.Web.SessionState;\r
  38 \r
  39 namespace System.Web {\r
  40         class HttpApplicationFactory {\r
  41                 private string _appFilename;\r
  42                 private Type _appType;\r
  43 \r
  44                 private bool _appInitialized;\r
  45                 private bool _appFiredEnd;\r
  46 \r
  47                 private Stack                   _appFreePublicList;\r
  48                 private int                             _appFreePublicInstances;\r
  49                 static private int      _appMaxFreePublicInstances = 32;\r
  50 \r
  51                 private HttpApplicationState _state;\r
  52 \r
  53                 static IHttpHandler custApplication;\r
  54 \r
  55                 static private HttpApplicationFactory s_Factory = new HttpApplicationFactory();\r
  56 \r
  57                 public HttpApplicationFactory() {\r
  58                         _appInitialized = false;\r
  59                         _appFiredEnd = false;\r
  60 \r
  61                         _appFreePublicList = new Stack();\r
  62                         _appFreePublicInstances = 0;\r
  63                 }\r
  64 \r
  65                 static private string GetAppFilename (HttpContext context)\r
  66                 {\r
  67                         string physicalAppPath = context.Request.PhysicalApplicationPath;\r
  68                         string appFilePath = Path.Combine (physicalAppPath, "Global.asax");\r
  69                         if (File.Exists (appFilePath))\r
  70                                 return appFilePath;\r
  71 \r
  72                         return Path.Combine (physicalAppPath, "global.asax");\r
  73                 }\r
  74 \r
  75                 private void CompileApp(HttpContext context) {\r
  76                         if (File.Exists(_appFilename)) {\r
  77                                 // Setup filemonitor for all filedepend also. CacheDependency?\r
  78 \r
  79                                 _appType = ApplicationFileParser.GetCompiledApplicationType (_appFilename, context);\r
  80                                 if (_appType == null) {\r
  81                                         string msg = String.Format ("Error compiling application file ({0}).", _appFilename);\r
  82                                         throw new ApplicationException (msg);\r
  83                                 }\r
  84                         } else {\r
  85                                 _appType = typeof (System.Web.HttpApplication);\r
  86                                 _state = new HttpApplicationState ();\r
  87                         }\r
  88                 }\r
  89 \r
  90                 static bool IsEventHandler (MethodInfo m)\r
  91                 {\r
  92                         if (m.ReturnType != typeof (void))\r
  93                                 return false;\r
  94 \r
  95                         ParameterInfo [] pi = m.GetParameters ();\r
  96                         int length = pi.Length;\r
  97                         if (length == 0)\r
  98                                 return true;\r
  99 \r
 100                         if (length != 2)\r
 101                                 return false;\r
 102 \r
 103                         if (pi [0].ParameterType != typeof (object) ||\r
 104                             pi [1].ParameterType != typeof (EventArgs))\r
 105                                 return false;\r
 106                         \r
 107                         return true;\r
 108                 }\r
 109 \r
 110                 static void AddEvent (MethodInfo method, Hashtable appTypeEventHandlers)\r
 111                 {\r
 112                         string name = method.Name.Replace ("_On", "_");\r
 113                         if (appTypeEventHandlers [name] == null) {\r
 114                                 appTypeEventHandlers [name] = method;\r
 115                                 return;\r
 116                         }\r
 117                         \r
 118                         ArrayList list;\r
 119                         if (appTypeEventHandlers [name] is MethodInfo)\r
 120                                 list = new ArrayList ();\r
 121                         else\r
 122                                 list = appTypeEventHandlers [name] as ArrayList;\r
 123 \r
 124                         list.Add (method);\r
 125                 }\r
 126                 \r
 127                 static Hashtable GetApplicationTypeEvents (HttpApplication app)\r
 128                 {\r
 129                         Type appType = app.GetType ();\r
 130                         Hashtable appTypeEventHandlers = new Hashtable ();\r
 131                         ArrayList evtMethods = new ArrayList ();\r
 132                         BindingFlags flags = BindingFlags.Public    |\r
 133                                              BindingFlags.NonPublic | \r
 134                                              BindingFlags.Instance |\r
 135                                              BindingFlags.Static;\r
 136 \r
 137                         MethodInfo [] methods = appType.GetMethods (flags);\r
 138                         foreach (MethodInfo m in methods) {\r
 139                                 if (IsEventHandler (m))\r
 140                                         AddEvent (m, appTypeEventHandlers);\r
 141                         }\r
 142 \r
 143                         return appTypeEventHandlers;\r
 144                 }\r
 145
 146                 static bool FireEvent (string method_name, object target, object [] args)
 147                 {
 148                         Hashtable possibleEvents = GetApplicationTypeEvents ((HttpApplication) target);
 149                         MethodInfo method = possibleEvents [method_name] as MethodInfo;
 150                         if (method == null)
 151                                 return false;
 152
 153                         if (method.GetParameters ().Length == 0)
 154                                 method.Invoke (target, null);
 155                         else
 156                                 method.Invoke (target, args);
 157
 158                         return true;
 159                 }
 160
 161                 internal static void FireOnAppStart (HttpApplication app)\r
 162                 {
 163                         object [] args = new object [] {app, EventArgs.Empty};\r
 164                         FireEvent ("Application_Start", app, args);\r
 165                 }
 166
 167                 void FireOnAppEnd ()
 168                 {
 169                         if (_appType == null)
 170                                 return; // we didn't even get an application
 171
 172                         HttpApplication app = (HttpApplication) HttpRuntime.CreateInternalObject (_appType);
 173                         AttachEvents (app);
 174                         FireEvent ("Application_End", app, new object [] {this, EventArgs.Empty});
 175                         app.Dispose ();
 176                 }
 177
 178                 private void InitializeFactory (HttpContext context)\r
 179                 {\r
 180                         _appFilename = GetAppFilename (context);\r
 181 \r
 182                         CompileApp (context);\r
 183 \r
 184                         // Create a application object\r
 185                         HttpApplication app = (HttpApplication) HttpRuntime.CreateInternalObject (_appType);\r
 186 \r
 187                         // Startup\r
 188                         app.Startup(context, HttpApplicationFactory.ApplicationState);\r
 189 \r
 190                         // Fire OnAppStart\r
 191                         HttpApplicationFactory.FireOnAppStart (app);\r
 192 \r
 193                         // Recycle our application instance\r
 194                         RecyclePublicInstance(app);\r
 195                 }\r
 196 \r
 197                 private void Dispose() {\r
 198                         ArrayList torelease = new ArrayList();\r
 199                         lock (_appFreePublicList) {\r
 200                                 while (_appFreePublicList.Count > 0) {\r
 201                                         torelease.Add(_appFreePublicList.Pop());\r
 202                                         _appFreePublicInstances--;\r
 203                                 }\r
 204                         }\r
 205 \r
 206                         if (torelease.Count > 0) {\r
 207                                 foreach (Object obj in torelease) {\r
 208                                         ((HttpApplication) obj).Cleanup();\r
 209                                 }\r
 210                         }\r
 211 \r
 212                         if (!_appFiredEnd) {\r
 213                                 lock (this) {\r
 214                                         if (!_appFiredEnd) {\r
 215                                                 FireOnAppEnd();\r
 216                                                 _appFiredEnd = true;\r
 217                                         }\r
 218                                 }\r
 219                         }\r
 220                 }\r
 221 \r
 222                 internal static IHttpHandler GetInstance(HttpContext context)\r
 223                 {\r
 224                         if (custApplication != null)\r
 225                                 return custApplication;\r
 226 \r
 227                         if (!s_Factory._appInitialized) {\r
 228                                 lock (s_Factory) {\r
 229                                         if (!s_Factory._appInitialized) {\r
 230                                                 s_Factory.InitializeFactory(context);\r
 231                                                 s_Factory._appInitialized = true;\r
 232                                         }\r
 233                                 }\r
 234                         }\r
 235 \r
 236                         return s_Factory.GetPublicInstance(context);\r
 237                 }\r
 238 \r
 239                 internal static void RecycleInstance(HttpApplication app) {\r
 240                         if (!s_Factory._appInitialized)\r
 241                                 throw new InvalidOperationException("Factory not intialized");\r
 242 \r
 243                         s_Factory.RecyclePublicInstance(app);\r
 244                 }\r
 245 \r
 246                 internal static void AttachEvents (HttpApplication app)\r
 247                 {\r
 248                         Hashtable possibleEvents = GetApplicationTypeEvents (app);\r
 249                         foreach (string key in possibleEvents.Keys) {\r
 250                                 int pos = key.IndexOf ('_');\r
 251                                 if (pos == -1 || key.Length <= pos + 1)\r
 252                                         continue;\r
 253 \r
 254                                 string moduleName = key.Substring (0, pos);\r
 255                                 object target;\r
 256                                 if (moduleName == "Application") {\r
 257                                         target = app;\r
 258                                 } else {\r
 259                                         target = app.Modules [moduleName];\r
 260                                         if (target == null)\r
 261                                                 continue;\r
 262                                 }\r
 263 \r
 264                                 string eventName = key.Substring (pos + 1);\r
 265                                 EventInfo evt = target.GetType ().GetEvent (eventName);\r
 266                                 if (evt == null)\r
 267                                         continue;\r
 268                         \r
 269                                 string usualName = moduleName + "_" + eventName;\r
 270                                 object methodData = possibleEvents [usualName];\r
 271                                 if (methodData == null)\r
 272                                         continue;\r
 273 \r
 274                                 if (methodData is MethodInfo) {\r
 275                                         AddHandler (evt, target, app, (MethodInfo) methodData);\r
 276                                         continue;\r
 277                                 }\r
 278 \r
 279                                 ArrayList list = (ArrayList) methodData;\r
 280                                 foreach (MethodInfo method in list)\r
 281                                         AddHandler (evt, target, app, method);\r
 282                         }\r
 283                 }\r
 284 \r
 285                 static void AddHandler (EventInfo evt, object target, HttpApplication app, MethodInfo method)\r
 286                 {\r
 287                         int length = method.GetParameters ().Length;\r
 288 \r
 289                         if (length == 0) {\r
 290                                 NoParamsInvoker npi = new NoParamsInvoker (app, method.Name);\r
 291                                 evt.AddEventHandler (target, npi.FakeDelegate);\r
 292                         } else {\r
 293                                 evt.AddEventHandler (target, Delegate.CreateDelegate (\r
 294                                                         typeof (EventHandler), app, method.Name));\r
 295                         }\r
 296                 }\r
 297 \r
 298                 private IHttpHandler GetPublicInstance(HttpContext context) {\r
 299                         HttpApplication app = null;\r
 300 \r
 301                         lock (_appFreePublicList) {\r
 302                                 if (_appFreePublicInstances > 0) {\r
 303                                         app = (HttpApplication) _appFreePublicList.Pop();\r
 304                                         _appFreePublicInstances--;\r
 305                                 }\r
 306                         }\r
 307 \r
 308                         if (app == null) {\r
 309                                 // Create non-public object\r
 310                                 app = (HttpApplication) HttpRuntime.CreateInternalObject(_appType);\r
 311 \r
 312                                 app.Startup(context, HttpApplicationFactory.ApplicationState);\r
 313                         }\r
 314 \r
 315                         return (IHttpHandler) app;\r
 316                 }\r
 317 \r
 318                 internal void RecyclePublicInstance(HttpApplication app) {\r
 319                         lock (_appFreePublicList) {\r
 320                                 if (_appFreePublicInstances < _appMaxFreePublicInstances) {\r
 321                                         _appFreePublicList.Push(app);\r
 322                                         _appFreePublicInstances++;\r
 323 \r
 324                                         app = null;\r
 325                                 }\r
 326                         }\r
 327                         \r
 328                         if  (app != null) {\r
 329                                 app.Cleanup();\r
 330                         }\r
 331                 }\r
 332 \r
 333                 static HttpStaticObjectsCollection MakeStaticCollection (ArrayList list)\r
 334                 {\r
 335                         if (list == null || list.Count == 0)\r
 336                                 return null;\r
 337 \r
 338                         HttpStaticObjectsCollection coll = new HttpStaticObjectsCollection ();\r
 339                         foreach (ObjectTagBuilder tag in list) {\r
 340                                 coll.Add (tag);\r
 341                         }\r
 342 \r
 343                         return coll;\r
 344                 }\r
 345                 \r
 346                 static internal HttpApplicationState ApplicationState {\r
 347                         get {\r
 348                                 if (null == s_Factory._state) {\r
 349                                         HttpStaticObjectsCollection app = MakeStaticCollection (GlobalAsaxCompiler.ApplicationObjects);\r
 350                                         HttpStaticObjectsCollection ses = MakeStaticCollection (GlobalAsaxCompiler.SessionObjects);\r
 351                                         s_Factory._state = new HttpApplicationState (app, ses);\r
 352                                 }\r
 353 \r
 354                                 return s_Factory._state;\r
 355                         }\r
 356                 }\r
 357 \r
 358                 internal static void EndApplication() {\r
 359                         s_Factory.Dispose();\r
 360                 }\r
 361 \r
 362                 public static void SetCustomApplication (IHttpHandler customApplication)\r
 363                 {\r
 364                         custApplication = customApplication;\r
 365                 }\r
 366 \r
 367                 internal Type AppType {\r
 368                         get { return _appType; }\r
 369                 }\r
 370 \r
 371                 internal static void SignalError(Exception exc) {\r
 372                         // TODO: Raise an error (we probably don't have a HttpContext)\r
 373                 }\r
 374         }\r
 375 }\r