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

   1 //
   2 // System.Web.HttpApplicationFactory
   3 //
   4 // Author:
   5 //      Gonzalo Paniagua Javier (gonzalo@ximian.com)
   6 //
   7 // (c) 2002,2003 Ximian, Inc. (http://www.ximian.com)
   8 // (c) Copyright 2004 Novell, Inc. (http://www.novell.com)
   9 //
  10 // Permission is hereby granted, free of charge, to any person obtaining
  11 // a copy of this software and associated documentation files (the
  12 // "Software"), to deal in the Software without restriction, including
  13 // without limitation the rights to use, copy, modify, merge, publish,
  14 // distribute, sublicense, and/or sell copies of the Software, and to
  15 // permit persons to whom the Software is furnished to do so, subject to
  16 // the following conditions:
  17 //
  18 // The above copyright notice and this permission notice shall be
  19 // included in all copies or substantial portions of the Software.
  20 //
  21 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  22 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  23 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  24 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  25 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  26 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  27 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  28 //
  29 using System;
  30 using System.Collections;
  31 using System.IO;
  32 using System.Reflection;
  33 using System.Web.UI;
  34 using System.Web.SessionState;
  35 using System.Web.Configuration;
  36
  37 #if !TARGET_J2EE
  38 using System.Web.Compilation;
  39 #else
  40 using vmw.common;
  41 #endif
  42
  43 namespace System.Web {
  44         class HttpApplicationFactory {
  45                 // Initialized in InitType
  46 #if TARGET_J2EE
  47                 static HttpApplicationFactory theFactory {
  48                         get
  49                         {
  50                                 HttpApplicationFactory factory = (HttpApplicationFactory)AppDomain.CurrentDomain.GetData("HttpApplicationFactory");
  51                                 if (factory == null) {
  52                                         lock(typeof(HttpApplicationFactory)) {
  53                                                 factory = (HttpApplicationFactory)AppDomain.CurrentDomain.GetData("HttpApplicationFactory");
  54                                                 if (factory == null) {
  55                                                         factory = new HttpApplicationFactory();
  56                                                         System.Threading.Thread.Sleep(1);
  57                                                         AppDomain.CurrentDomain.SetData("HttpApplicationFactory", factory);
  58                                                 }
  59                                         }
  60                                 }
  61                                 return factory;
  62                         }
  63                 }
  64 #else
  65                 static HttpApplicationFactory theFactory = new HttpApplicationFactory();
  66 #endif
  67
  68                 static MethodInfo session_end;
  69                 bool needs_init = true;
  70                 bool app_start_needed = true;
  71                 Type app_type;
  72                 HttpApplicationState app_state;
  73                 Hashtable app_event_handlers;
  74 #if !TARGET_JVM
  75                 FileSystemWatcher app_file_watcher;
  76                 FileSystemWatcher bin_watcher;
  77 #endif
  78                 Stack available = new Stack ();
  79                 Stack available_for_end = new Stack ();
  80
  81                 // Watch this thing out when getting an instance
  82                 IHttpHandler custom_application;
  83
  84                 bool IsEventHandler (MethodInfo m)
  85                 {
  86                         int pos = m.Name.IndexOf ('_');
  87                         if (pos == -1 || (m.Name.Length - 1) <= pos)
  88                                 return false;
  89
  90                         if (m.ReturnType != typeof (void))
  91                                 return false;
  92
  93                         ParameterInfo [] pi = m.GetParameters ();
  94                         int length = pi.Length;
  95                         if (length == 0)
  96                                 return true;
  97
  98                         if (length != 2)
  99                                 return false;
 100
 101                         if (pi [0].ParameterType != typeof (object) ||
 102                             pi [1].ParameterType != typeof (EventArgs))
 103                                 return false;
 104
 105                         return true;
 106                 }
 107
 108                 void AddEvent (MethodInfo method, Hashtable appTypeEventHandlers)
 109                 {
 110                         string name = method.Name.Replace ("_On", "_");
 111                         if (appTypeEventHandlers [name] == null) {
 112                                 appTypeEventHandlers [name] = method;
 113                                 return;
 114                         }
 115
 116                         MethodInfo old_method = appTypeEventHandlers [name] as MethodInfo;
 117                         ArrayList list;
 118                         if (old_method != null){
 119                                 list = new ArrayList (4);
 120                                 list.Add (old_method);
 121                                 appTypeEventHandlers [name] = list;
 122                         } else
 123                                 list = appTypeEventHandlers [name] as ArrayList;
 124
 125                         list.Add (method);
 126                 }
 127
 128                 Hashtable GetApplicationTypeEvents (Type type)
 129                 {
 130                         lock (this) {
 131                                 if (app_event_handlers != null)
 132                                         return app_event_handlers;
 133
 134                                 app_event_handlers = new Hashtable ();
 135                                 BindingFlags flags = BindingFlags.Public    | BindingFlags.NonPublic |
 136                                                      BindingFlags.Instance  | BindingFlags.Static;
 137
 138                                 MethodInfo [] methods = type.GetMethods (flags);
 139                                 foreach (MethodInfo m in methods) {
 140                                         if (m.DeclaringType != typeof (HttpApplication) && IsEventHandler (m))
 141                                                 AddEvent (m, app_event_handlers);
 142                                 }
 143                         }
 144
 145                         return app_event_handlers;
 146                 }
 147
 148                 Hashtable GetApplicationTypeEvents (HttpApplication app)
 149                 {
 150                         lock (this) {
 151                                 if (app_event_handlers != null)
 152                                         return app_event_handlers;
 153
 154                                 return GetApplicationTypeEvents (app.GetType ());
 155                         }
 156                 }
 157
 158                 bool FireEvent (string method_name, object target, object [] args)
 159                 {
 160                         Hashtable possibleEvents = GetApplicationTypeEvents ((HttpApplication) target);
 161                         MethodInfo method = possibleEvents [method_name] as MethodInfo;
 162                         if (method == null)
 163                                 return false;
 164
 165                         if (method.GetParameters ().Length == 0)
 166                                 args = null;
 167
 168                         method.Invoke (target, args);
 169
 170                         return true;
 171                 }
 172
 173                 HttpApplication FireOnAppStart (HttpContext context)
 174                 {
 175                         HttpApplication app = (HttpApplication) Activator.CreateInstance (app_type, true);
 176                         context.ApplicationInstance = app;
 177                         app.SetContext (context);
 178                         object [] args = new object [] {app, EventArgs.Empty};
 179                         FireEvent ("Application_Start", app, args);
 180                         return app;
 181                 }
 182
 183                 void FireOnAppEnd ()
 184                 {
 185                         if (app_type == null)
 186                                 return; // we didn't even get an application
 187
 188                         HttpApplication app = (HttpApplication) Activator.CreateInstance (app_type, true);
 189                         FireEvent ("Application_End", app, new object [] {new object (), EventArgs.Empty});
 190                         app.Dispose ();
 191                 }
 192
 193                 //
 194                 // This is invoked by HttpRuntime.Dispose, when we unload an AppDomain
 195                 // To reproduce this in action, touch "global.asax" while XSP is running.
 196                 //
 197                 public static void Dispose ()
 198                 {
 199                         theFactory.FireOnAppEnd ();
 200                 }
 201
 202 #if !TARGET_JVM
 203                 static FileSystemWatcher CreateWatcher (string file, FileSystemEventHandler hnd)
 204                 {
 205                         FileSystemWatcher watcher = new FileSystemWatcher ();
 206
 207                         watcher.Path = Path.GetFullPath (Path.GetDirectoryName (file));
 208                         watcher.Filter = Path.GetFileName (file);
 209
 210                         watcher.Changed += hnd;
 211                         watcher.Created += hnd;
 212                         watcher.Deleted += hnd;
 213
 214                         watcher.EnableRaisingEvents = true;
 215
 216                         return watcher;
 217                 }
 218
 219                 void OnAppFileChanged (object sender, FileSystemEventArgs args)
 220                 {
 221                         if (bin_watcher != null)
 222                                 bin_watcher.EnableRaisingEvents = false;
 223                         if (app_file_watcher != null)
 224                                 app_file_watcher.EnableRaisingEvents = false;
 225                         HttpRuntime.UnloadAppDomain ();
 226                 }
 227 #endif
 228
 229                 internal static void AttachEvents (HttpApplication app)
 230                 {
 231                         HttpApplicationFactory factory = theFactory;
 232                         Hashtable possibleEvents = factory.GetApplicationTypeEvents (app);
 233                         foreach (string key in possibleEvents.Keys) {
 234                                 int pos = key.IndexOf ('_');
 235                                 string moduleName = key.Substring (0, pos);
 236                                 object target;
 237                                 if (moduleName == "Application") {
 238                                         target = app;
 239                                 } else {
 240                                         target = app.Modules [moduleName];
 241                                         if (target == null)
 242                                                 continue;
 243                                 }
 244
 245                                 string eventName = key.Substring (pos + 1);
 246                                 EventInfo evt = target.GetType ().GetEvent (eventName);
 247                                 if (evt == null)
 248                                         continue;
 249
 250                                 string usualName = moduleName + "_" + eventName;
 251                                 object methodData = possibleEvents [usualName];
 252                                 if (methodData != null && eventName == "End" && moduleName == "Session") {
 253                                         lock (factory) {
 254                                                 if (session_end == null)
 255                                                         session_end = (MethodInfo) methodData;
 256                                         }
 257                                         continue;
 258                                 }
 259
 260                                 if (methodData == null)
 261                                         continue;
 262
 263                                 if (methodData is MethodInfo) {
 264                                         factory.AddHandler (evt, target, app, (MethodInfo) methodData);
 265                                         continue;
 266                                 }
 267
 268                                 ArrayList list = (ArrayList) methodData;
 269                                 foreach (MethodInfo method in list)
 270                                         factory.AddHandler (evt, target, app, method);
 271                         }
 272                 }
 273
 274                 void AddHandler (EventInfo evt, object target, HttpApplication app, MethodInfo method)
 275                 {
 276                         int length = method.GetParameters ().Length;
 277
 278                         if (length == 0) {
 279                                 NoParamsInvoker npi = new NoParamsInvoker (app, method.Name);
 280                                 evt.AddEventHandler (target, npi.FakeDelegate);
 281                         } else {
 282                                 evt.AddEventHandler (target, Delegate.CreateDelegate (
 283                                                         typeof (EventHandler), app, method.Name));
 284                         }
 285                 }
 286
 287                 internal static void InvokeSessionEnd (object state)
 288                 {
 289                         HttpApplicationFactory factory = theFactory;
 290                         MethodInfo method = null;
 291                         HttpApplication app = null;
 292                         lock (factory.available_for_end) {
 293                                 method = session_end;
 294                                 if (method == null)
 295                                         return;
 296
 297                                 app = GetApplicationForSessionEnd ();
 298                         }
 299
 300                         app.SetSession ((HttpSessionState) state);
 301                         try {
 302                                 method.Invoke (app, new object [] {app, EventArgs.Empty});
 303                         } catch (Exception e) {
 304                                 // Ignore
 305                         }
 306                         RecycleForSessionEnd (app);
 307                 }
 308
 309                 static HttpStaticObjectsCollection MakeStaticCollection (ArrayList list)
 310                 {
 311                         if (list == null || list.Count == 0)
 312                                 return null;
 313
 314                         HttpStaticObjectsCollection coll = new HttpStaticObjectsCollection ();
 315                         foreach (ObjectTagBuilder tag in list) {
 316                                 coll.Add (tag);
 317                         }
 318
 319                         return coll;
 320                 }
 321
 322                 internal static HttpApplicationState ApplicationState {
 323 #if TARGET_J2EE
 324                         get {
 325                                 HttpApplicationFactory factory = theFactory;
 326                                 if (factory.app_state == null)
 327                                         factory.app_state = new HttpApplicationState (null, null);
 328                                 return factory.app_state;
 329                         }
 330 #else
 331                         get {
 332                                 if (theFactory.app_state == null) {
 333                                         HttpStaticObjectsCollection app = MakeStaticCollection (GlobalAsaxCompiler.ApplicationObjects);
 334                                         HttpStaticObjectsCollection ses = MakeStaticCollection (GlobalAsaxCompiler.SessionObjects);
 335
 336                                         theFactory.app_state = new HttpApplicationState (app, ses);
 337                                 }
 338                                 return theFactory.app_state;
 339                         }
 340 #endif
 341                 }
 342
 343                 public static void SetCustomApplication (IHttpHandler customApplication)
 344                 {
 345                         theFactory.custom_application = customApplication;
 346                 }
 347
 348                 internal static Type AppType {
 349                         get {
 350                                 return theFactory.app_type;
 351                         }
 352                 }
 353
 354                 void InitType (HttpContext context)
 355                 {
 356                         lock (this) {
 357                                 if (!needs_init)
 358                                         return;
 359
 360                                 string physical_app_path = context.Request.PhysicalApplicationPath;
 361                                 string app_file;
 362
 363                                 app_file = Path.Combine (physical_app_path, "Global.asax");
 364                                 if (!File.Exists (app_file))
 365                                         app_file = Path.Combine (physical_app_path, "global.asax");
 366
 367 #if !CONFIGURATION_2_0
 368                                 WebConfigurationSettings.Init (context);
 369 #endif
 370
 371                                 if (File.Exists (app_file)) {
 372 #if TARGET_J2EE
 373                                         app_type = System.Web.J2EE.PageMapper.GetObjectType(app_file);
 374 #else
 375                                         app_type = ApplicationFileParser.GetCompiledApplicationType (app_file, context);
 376                                         if (app_type == null) {
 377                                                 string msg = String.Format ("Error compiling application file ({0}).", app_file);
 378                                                 throw new ApplicationException (msg);
 379                                         }
 380
 381                                         app_file_watcher = CreateWatcher (app_file, new FileSystemEventHandler (OnAppFileChanged));
 382 #endif
 383                                 } else {
 384                                         app_type = typeof (System.Web.HttpApplication);
 385                                         app_state = new HttpApplicationState ();
 386                                 }
 387                                 needs_init = false;
 388
 389                                 //
 390                                 // Now init the settings
 391                                 //
 392
 393                         }
 394                 }
 395
 396                 //
 397                 // Multiple-threads might hit this one on startup, and we have
 398                 // to delay-initialize until we have the HttpContext
 399                 //
 400                 internal static HttpApplication GetApplication (HttpContext context)
 401                 {
 402                         HttpApplicationFactory factory = theFactory;
 403                         HttpApplication app = null;
 404                         if (factory.needs_init){
 405                                 if (context == null)
 406                                         return null;
 407
 408                                 factory.InitType (context);
 409                                 lock (factory) {
 410                                         if (factory.app_start_needed) {
 411 #if !TARGET_JVM
 412                                                 string bin = HttpRuntime.BinDirectory;
 413                                                 if (Directory.Exists (bin))
 414                                                         bin = Path.Combine (bin, "*.dll");
 415
 416                                                 // We watch bin or bin/*.dll if the directory exists
 417                                                 factory.bin_watcher = CreateWatcher (bin, new FileSystemEventHandler (factory.OnAppFileChanged));
 418 #endif
 419                                                 app = factory.FireOnAppStart (context);
 420                                                 factory.app_start_needed = false;
 421                                                 return app;
 422                                         }
 423                                 }
 424                         }
 425
 426                         lock (factory.available) {
 427                                 if (factory.available.Count > 0) {
 428                                         app = (HttpApplication) factory.available.Pop ();
 429                                         app.RequestCompleted = false;
 430                                         return app;
 431                                 }
 432                         }
 433
 434                         return (HttpApplication) Activator.CreateInstance (factory.app_type, true);
 435                 }
 436
 437                 // The lock is in InvokeSessionEnd
 438                 static HttpApplication GetApplicationForSessionEnd ()
 439                 {
 440                         HttpApplicationFactory factory = theFactory;
 441                         if (factory.available_for_end.Count > 0)
 442                                 return (HttpApplication) factory.available_for_end.Pop ();
 443
 444                         HttpApplication app = (HttpApplication) Activator.CreateInstance (factory.app_type, true);
 445                         app.InitOnce (false);
 446
 447                         return app;
 448                 }
 449
 450                 internal static void RecycleForSessionEnd (HttpApplication app)
 451                 {
 452                         HttpApplicationFactory factory = theFactory;
 453                         lock (factory.available_for_end) {
 454                                 if (factory.available_for_end.Count < 32)
 455                                         factory.available_for_end.Push (app);
 456                                 else
 457                                         app.Dispose ();
 458                         }
 459                 }
 460
 461                 internal static void Recycle (HttpApplication app)
 462                 {
 463                         HttpApplicationFactory factory = theFactory;
 464                         lock (factory.available) {
 465                                 if (factory.available.Count < 32)
 466                                         factory.available.Push (app);
 467                                 else
 468                                         app.Dispose ();
 469                         }
 470                 }
 471
 472                 internal static bool ContextAvailable {
 473                         get { return theFactory != null && theFactory.app_start_needed && theFactory.needs_init; }
 474                 }
 475         }
 476 }
 477