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

   1 //
   2 // System.Web.HttpApplicationFactory
   3 //
   4 // TODO:
   5 //   bin_watcher must work.
   6 //
   7 //
   8 // Author:
   9 //      Gonzalo Paniagua Javier (gonzalo@ximian.com)
  10 //
  11 // (c) 2002,2003 Ximian, Inc. (http://www.ximian.com)
  12 // (c) Copyright 2004 Novell, Inc. (http://www.novell.com)
  13 //
  14 // Permission is hereby granted, free of charge, to any person obtaining
  15 // a copy of this software and associated documentation files (the
  16 // "Software"), to deal in the Software without restriction, including
  17 // without limitation the rights to use, copy, modify, merge, publish,
  18 // distribute, sublicense, and/or sell copies of the Software, and to
  19 // permit persons to whom the Software is furnished to do so, subject to
  20 // the following conditions:
  21 //
  22 // The above copyright notice and this permission notice shall be
  23 // included in all copies or substantial portions of the Software.
  24 //
  25 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  26 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  27 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  28 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  29 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  30 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  31 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  32 //
  33 using System;
  34 using System.Collections;
  35 using System.IO;
  36 using System.Reflection;
  37 using System.Web.UI;
  38 using System.Web.SessionState;
  39 using System.Web.Configuration;
  40
  41 #if !TARGET_J2EE
  42 using System.Web.Compilation;
  43 #else
  44 using vmw.common;
  45 #endif
  46
  47 namespace System.Web {
  48         class HttpApplicationFactory {
  49                 // Initialized in InitType
  50 #if TARGET_J2EE
  51                 static HttpApplicationFactory theFactory {
  52                         get
  53                         {
  54                                 HttpApplicationFactory factory = (HttpApplicationFactory)AppDomain.CurrentDomain.GetData("HttpApplicationFactory");
  55                                 if (factory == null) {
  56                                         lock(typeof(HttpApplicationFactory)) {
  57                                                 factory = (HttpApplicationFactory)AppDomain.CurrentDomain.GetData("HttpApplicationFactory");
  58                                                 if (factory == null) {
  59                                                         factory = new HttpApplicationFactory();
  60                                                         System.Threading.Thread.Sleep(1);
  61                                                         AppDomain.CurrentDomain.SetData("HttpApplicationFactory", factory);
  62                                                 }
  63                                         }
  64                                 }
  65                                 return factory;
  66                         }
  67                 }
  68 #else
  69                 static HttpApplicationFactory theFactory = new HttpApplicationFactory();
  70 #endif
  71
  72                 bool needs_init = true;
  73                 bool app_start_needed = true;
  74                 Type app_type;
  75                 HttpApplicationState app_state;
  76 #if !TARGET_JVM
  77                 FileSystemWatcher app_file_watcher;
  78                 FileSystemWatcher bin_watcher;
  79 #endif
  80                 Stack available = new Stack ();
  81
  82                 // Watch this thing out when getting an instance
  83                 IHttpHandler custom_application;
  84
  85                 bool IsEventHandler (MethodInfo m)
  86                 {
  87                         if (m.ReturnType != typeof (void))
  88                                 return false;
  89
  90                         ParameterInfo [] pi = m.GetParameters ();
  91                         int length = pi.Length;
  92                         if (length == 0)
  93                                 return true;
  94
  95                         if (length != 2)
  96                                 return false;
  97
  98                         if (pi [0].ParameterType != typeof (object) ||
  99                             pi [1].ParameterType != typeof (EventArgs))
 100                                 return false;
 101
 102                         return true;
 103                 }
 104
 105                 void AddEvent (MethodInfo method, Hashtable appTypeEventHandlers)
 106                 {
 107                         string name = method.Name.Replace ("_On", "_");
 108                         if (appTypeEventHandlers [name] == null) {
 109                                 appTypeEventHandlers [name] = method;
 110                                 return;
 111                         }
 112
 113                         MethodInfo old_method = appTypeEventHandlers [name] as MethodInfo;
 114                         ArrayList list;
 115                         if (old_method != null){
 116                                 list = new ArrayList (4);
 117                                 list.Add (old_method);
 118                                 appTypeEventHandlers [name] = list;
 119                         } else
 120                                 list = appTypeEventHandlers [name] as ArrayList;
 121
 122                         list.Add (method);
 123                 }
 124
 125                 Hashtable GetApplicationTypeEvents (HttpApplication app)
 126                 {
 127                         Type appType = app.GetType ();
 128                         Hashtable appTypeEventHandlers = new Hashtable ();
 129                         BindingFlags flags = BindingFlags.Public    |
 130                                              BindingFlags.NonPublic |
 131                                              BindingFlags.Instance |
 132                                              BindingFlags.Static;
 133
 134                         MethodInfo [] methods = appType.GetMethods (flags);
 135                         foreach (MethodInfo m in methods) {
 136                                 if (IsEventHandler (m))
 137                                         AddEvent (m, appTypeEventHandlers);
 138                         }
 139
 140                         return appTypeEventHandlers;
 141                 }
 142
 143                 bool FireEvent (string method_name, object target, object [] args)
 144                 {
 145                         Hashtable possibleEvents = GetApplicationTypeEvents ((HttpApplication) target);
 146                         MethodInfo method = possibleEvents [method_name] as MethodInfo;
 147                         if (method == null)
 148                                 return false;
 149
 150                         if (method.GetParameters ().Length == 0)
 151                                 args = null;
 152
 153                         method.Invoke (target, args);
 154
 155                         return true;
 156                 }
 157
 158                 void FireOnAppStart (HttpContext context)
 159                 {
 160                         HttpApplication app = (HttpApplication) Activator.CreateInstance (app_type, true);
 161                         app.SetContext (context);
 162                         object [] args = new object [] {app, EventArgs.Empty};
 163                         FireEvent ("Application_Start", app, args);
 164                         Recycle (app);
 165                 }
 166
 167                 void FireOnAppEnd ()
 168                 {
 169                         if (app_type == null)
 170                                 return; // we didn't even get an application
 171
 172                         HttpApplication app = (HttpApplication) Activator.CreateInstance (app_type, true);
 173                         FireEvent ("Application_End", app, new object [] {new object (), EventArgs.Empty});
 174                         app.Dispose ();
 175                 }
 176
 177                 //
 178                 // This is invoked by HttpRuntime.Dispose, when we unload an AppDomain
 179                 // To reproduce this in action, touch "global.asax" while XSP is running.
 180                 //
 181                 public static void Dispose ()
 182                 {
 183                         theFactory.FireOnAppEnd ();
 184                 }
 185
 186 #if !TARGET_JVM
 187                 FileSystemWatcher CreateWatcher (string file, FileSystemEventHandler hnd)
 188                 {
 189                         FileSystemWatcher watcher = new FileSystemWatcher ();
 190
 191                         watcher.Path = Path.GetFullPath (Path.GetDirectoryName (file));
 192                         watcher.Filter = Path.GetFileName (file);
 193
 194                         watcher.Changed += hnd;
 195                         watcher.Created += hnd;
 196                         watcher.Deleted += hnd;
 197
 198                         watcher.EnableRaisingEvents = true;
 199
 200                         return watcher;
 201                 }
 202
 203                 void OnAppFileChanged (object sender, FileSystemEventArgs args)
 204                 {
 205                         bin_watcher.EnableRaisingEvents = false;
 206                         app_file_watcher.EnableRaisingEvents = false;
 207                         HttpRuntime.UnloadAppDomain ();
 208                 }
 209 #endif
 210
 211                 internal static void AttachEvents (HttpApplication app)
 212                 {
 213                         HttpApplicationFactory factory = theFactory;
 214                         Hashtable possibleEvents = factory.GetApplicationTypeEvents (app);
 215                         foreach (string key in possibleEvents.Keys) {
 216                                 int pos = key.IndexOf ('_');
 217                                 if (pos == -1 || key.Length <= pos + 1)
 218                                         continue;
 219
 220                                 string moduleName = key.Substring (0, pos);
 221                                 object target;
 222                                 if (moduleName == "Application") {
 223                                         target = app;
 224                                 } else {
 225                                         target = app.Modules [moduleName];
 226                                         if (target == null)
 227                                                 continue;
 228                                 }
 229
 230                                 string eventName = key.Substring (pos + 1);
 231                                 EventInfo evt = target.GetType ().GetEvent (eventName);
 232                                 if (evt == null)
 233                                         continue;
 234
 235                                 string usualName = moduleName + "_" + eventName;
 236                                 object methodData = possibleEvents [usualName];
 237                                 if (methodData == null)
 238                                         continue;
 239
 240                                 if (methodData is MethodInfo) {
 241                                         factory.AddHandler (evt, target, app, (MethodInfo) methodData);
 242                                         continue;
 243                                 }
 244
 245                                 ArrayList list = (ArrayList) methodData;
 246                                 foreach (MethodInfo method in list)
 247                                         factory.AddHandler (evt, target, app, method);
 248                         }
 249                 }
 250
 251                 void AddHandler (EventInfo evt, object target, HttpApplication app, MethodInfo method)
 252                 {
 253                         int length = method.GetParameters ().Length;
 254
 255                         if (length == 0) {
 256                                 NoParamsInvoker npi = new NoParamsInvoker (app, method.Name);
 257                                 evt.AddEventHandler (target, npi.FakeDelegate);
 258                         } else {
 259                                 evt.AddEventHandler (target, Delegate.CreateDelegate (
 260                                                         typeof (EventHandler), app, method.Name));
 261                         }
 262                 }
 263
 264                 static HttpStaticObjectsCollection MakeStaticCollection (ArrayList list)
 265                 {
 266                         if (list == null || list.Count == 0)
 267                                 return null;
 268
 269                         HttpStaticObjectsCollection coll = new HttpStaticObjectsCollection ();
 270                         foreach (ObjectTagBuilder tag in list) {
 271                                 coll.Add (tag);
 272                         }
 273
 274                         return coll;
 275                 }
 276
 277                 internal static HttpApplicationState ApplicationState {
 278 #if TARGET_J2EE
 279                         get {
 280                                 HttpApplicationFactory factory = theFactory;
 281                                 if (factory.app_state == null)
 282                                         factory.app_state = new HttpApplicationState (null, null);
 283                                 return factory.app_state;
 284                         }
 285 #else
 286                         get {
 287                                 if (theFactory.app_state == null) {
 288                                         HttpStaticObjectsCollection app = MakeStaticCollection (GlobalAsaxCompiler.ApplicationObjects);
 289                                         HttpStaticObjectsCollection ses = MakeStaticCollection (GlobalAsaxCompiler.SessionObjects);
 290
 291                                         theFactory.app_state = new HttpApplicationState (app, ses);
 292                                 }
 293                                 return theFactory.app_state;
 294                         }
 295 #endif
 296                 }
 297
 298                 public static void SetCustomApplication (IHttpHandler customApplication)
 299                 {
 300                         theFactory.custom_application = customApplication;
 301                 }
 302
 303                 internal static Type AppType {
 304                         get {
 305                                 return theFactory.app_type;
 306                         }
 307                 }
 308
 309                 void InitType (HttpContext context)
 310                 {
 311                         lock (this) {
 312                                 if (!needs_init)
 313                                         return;
 314
 315                                 string physical_app_path = context.Request.PhysicalApplicationPath;
 316                                 string app_file;
 317
 318                                 app_file = Path.Combine (physical_app_path, "Global.asax");
 319                                 if (!File.Exists (app_file))
 320                                         app_file = Path.Combine (physical_app_path, "global.asax");
 321
 322                                 WebConfigurationSettings.Init (context);
 323
 324                                 if (File.Exists (app_file)) {
 325 #if TARGET_J2EE
 326                                         app_type = System.Web.J2EE.PageMapper.GetObjectType(app_file);
 327 #else
 328                                         app_type = ApplicationFileParser.GetCompiledApplicationType (app_file, context);
 329                                         if (app_type == null) {
 330                                                 string msg = String.Format ("Error compiling application file ({0}).", app_file);
 331                                                 throw new ApplicationException (msg);
 332                                         }
 333
 334                                         app_file_watcher = CreateWatcher (app_file, new FileSystemEventHandler (OnAppFileChanged));
 335 #endif
 336                                 } else {
 337                                         app_type = typeof (System.Web.HttpApplication);
 338                                         app_state = new HttpApplicationState ();
 339                                 }
 340                                 needs_init = false;
 341
 342                                 //
 343                                 // Now init the settings
 344                                 //
 345
 346                         }
 347                 }
 348
 349                 //
 350                 // Multiple-threads might hit this one on startup, and we have
 351                 // to delay-initialize until we have the HttpContext
 352                 //
 353                 internal static HttpApplication GetApplication (HttpContext context)
 354                 {
 355                         HttpApplicationFactory factory = theFactory;
 356                         if (factory.needs_init){
 357                                 if (context == null)
 358                                         return null;
 359
 360                                 factory.InitType (context);
 361                                 lock (factory) {
 362                                         if (factory.app_start_needed) {
 363                                                 factory.FireOnAppStart (context);
 364                                                 factory.app_start_needed = false;
 365                                         }
 366                                 }
 367                         }
 368
 369                         lock (factory) {
 370                                 if (factory.available.Count > 0)
 371                                         return (HttpApplication) factory.available.Pop ();
 372                         }
 373
 374                         HttpApplication app = (HttpApplication) Activator.CreateInstance (factory.app_type, true);
 375
 376                         return app;
 377                 }
 378
 379                 internal static void Recycle (HttpApplication app)
 380                 {
 381                         HttpApplicationFactory factory = theFactory;
 382                         lock (factory) {
 383                                 if (factory.available.Count < 32)
 384                                         factory.available.Push (app);
 385                                 else
 386                                         app.Dispose ();
 387                         }
 388                 }
 389         }
 390 }