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                 void FireOnAppStart (HttpContext context)
 174                 {
 175                         HttpApplication app = (HttpApplication) Activator.CreateInstance (app_type, true);
 176                         app.SetContext (context);
 177                         object [] args = new object [] {app, EventArgs.Empty};
 178                         FireEvent ("Application_Start", app, args);
 179                         Recycle (app);
 180                 }
 181
 182                 void FireOnAppEnd ()
 183                 {
 184                         if (app_type == null)
 185                                 return; // we didn't even get an application
 186
 187                         HttpApplication app = (HttpApplication) Activator.CreateInstance (app_type, true);
 188                         FireEvent ("Application_End", app, new object [] {new object (), EventArgs.Empty});
 189                         app.Dispose ();
 190                 }
 191
 192                 //
 193                 // This is invoked by HttpRuntime.Dispose, when we unload an AppDomain
 194                 // To reproduce this in action, touch "global.asax" while XSP is running.
 195                 //
 196                 public static void Dispose ()
 197                 {
 198                         theFactory.FireOnAppEnd ();
 199                 }
 200
 201 #if !TARGET_JVM
 202                 static FileSystemWatcher CreateWatcher (string file, FileSystemEventHandler hnd)
 203                 {
 204                         FileSystemWatcher watcher = new FileSystemWatcher ();
 205
 206                         watcher.Path = Path.GetFullPath (Path.GetDirectoryName (file));
 207                         watcher.Filter = Path.GetFileName (file);
 208
 209                         watcher.Changed += hnd;
 210                         watcher.Created += hnd;
 211                         watcher.Deleted += hnd;
 212
 213                         watcher.EnableRaisingEvents = true;
 214
 215                         return watcher;
 216                 }
 217
 218                 void OnAppFileChanged (object sender, FileSystemEventArgs args)
 219                 {
 220                         if (bin_watcher != null)
 221                                 bin_watcher.EnableRaisingEvents = false;
 222                         if (app_file_watcher != null)
 223                                 app_file_watcher.EnableRaisingEvents = false;
 224                         HttpRuntime.UnloadAppDomain ();
 225                 }
 226 #endif
 227
 228                 internal static void AttachEvents (HttpApplication app)
 229                 {
 230                         HttpApplicationFactory factory = theFactory;
 231                         Hashtable possibleEvents = factory.GetApplicationTypeEvents (app);
 232                         foreach (string key in possibleEvents.Keys) {
 233                                 int pos = key.IndexOf ('_');
 234                                 string moduleName = key.Substring (0, pos);
 235                                 object target;
 236                                 if (moduleName == "Application") {
 237                                         target = app;
 238                                 } else {
 239                                         target = app.Modules [moduleName];
 240                                         if (target == null)
 241                                                 continue;
 242                                 }
 243
 244                                 string eventName = key.Substring (pos + 1);
 245                                 EventInfo evt = target.GetType ().GetEvent (eventName);
 246                                 if (evt == null)
 247                                         continue;
 248
 249                                 string usualName = moduleName + "_" + eventName;
 250                                 object methodData = possibleEvents [usualName];
 251                                 if (methodData != null && eventName == "End" && moduleName == "Session") {
 252                                         lock (factory) {
 253                                                 if (session_end == null)
 254                                                         session_end = (MethodInfo) methodData;
 255                                         }
 256                                         continue;
 257                                 }
 258
 259                                 if (methodData == null)
 260                                         continue;
 261
 262                                 if (methodData is MethodInfo) {
 263                                         factory.AddHandler (evt, target, app, (MethodInfo) methodData);
 264                                         continue;
 265                                 }
 266
 267                                 ArrayList list = (ArrayList) methodData;
 268                                 foreach (MethodInfo method in list)
 269                                         factory.AddHandler (evt, target, app, method);
 270                         }
 271                 }
 272
 273                 void AddHandler (EventInfo evt, object target, HttpApplication app, MethodInfo method)
 274                 {
 275                         int length = method.GetParameters ().Length;
 276
 277                         if (length == 0) {
 278                                 NoParamsInvoker npi = new NoParamsInvoker (app, method.Name);
 279                                 evt.AddEventHandler (target, npi.FakeDelegate);
 280                         } else {
 281                                 evt.AddEventHandler (target, Delegate.CreateDelegate (
 282                                                         typeof (EventHandler), app, method.Name));
 283                         }
 284                 }
 285
 286                 internal static void InvokeSessionEnd (object state)
 287                 {
 288                         HttpApplicationFactory factory = theFactory;
 289                         MethodInfo method = null;
 290                         HttpApplication app = null;
 291                         lock (factory.available_for_end) {
 292                                 method = session_end;
 293                                 if (method == null)
 294                                         return;
 295
 296                                 app = GetApplicationForSessionEnd ();
 297                         }
 298
 299                         app.SetSession ((HttpSessionState) state);
 300                         try {
 301                                 method.Invoke (app, new object [] {app, EventArgs.Empty});
 302                         } catch (Exception e) {
 303                                 // Ignore
 304                         }
 305                         RecycleForSessionEnd (app);
 306                 }
 307
 308                 static HttpStaticObjectsCollection MakeStaticCollection (ArrayList list)
 309                 {
 310                         if (list == null || list.Count == 0)
 311                                 return null;
 312
 313                         HttpStaticObjectsCollection coll = new HttpStaticObjectsCollection ();
 314                         foreach (ObjectTagBuilder tag in list) {
 315                                 coll.Add (tag);
 316                         }
 317
 318                         return coll;
 319                 }
 320
 321                 internal static HttpApplicationState ApplicationState {
 322 #if TARGET_J2EE
 323                         get {
 324                                 HttpApplicationFactory factory = theFactory;
 325                                 if (factory.app_state == null)
 326                                         factory.app_state = new HttpApplicationState (null, null);
 327                                 return factory.app_state;
 328                         }
 329 #else
 330                         get {
 331                                 if (theFactory.app_state == null) {
 332                                         HttpStaticObjectsCollection app = MakeStaticCollection (GlobalAsaxCompiler.ApplicationObjects);
 333                                         HttpStaticObjectsCollection ses = MakeStaticCollection (GlobalAsaxCompiler.SessionObjects);
 334
 335                                         theFactory.app_state = new HttpApplicationState (app, ses);
 336                                 }
 337                                 return theFactory.app_state;
 338                         }
 339 #endif
 340                 }
 341
 342                 public static void SetCustomApplication (IHttpHandler customApplication)
 343                 {
 344                         theFactory.custom_application = customApplication;
 345                 }
 346
 347                 internal static Type AppType {
 348                         get {
 349                                 return theFactory.app_type;
 350                         }
 351                 }
 352
 353                 void InitType (HttpContext context)
 354                 {
 355                         lock (this) {
 356                                 if (!needs_init)
 357                                         return;
 358
 359                                 string physical_app_path = context.Request.PhysicalApplicationPath;
 360                                 string app_file;
 361
 362                                 app_file = Path.Combine (physical_app_path, "Global.asax");
 363                                 if (!File.Exists (app_file))
 364                                         app_file = Path.Combine (physical_app_path, "global.asax");
 365
 366                                 WebConfigurationSettings.Init (context);
 367
 368                                 if (File.Exists (app_file)) {
 369 #if TARGET_J2EE
 370                                         app_type = System.Web.J2EE.PageMapper.GetObjectType(app_file);
 371 #else
 372                                         app_type = ApplicationFileParser.GetCompiledApplicationType (app_file, context);
 373                                         if (app_type == null) {
 374                                                 string msg = String.Format ("Error compiling application file ({0}).", app_file);
 375                                                 throw new ApplicationException (msg);
 376                                         }
 377
 378                                         app_file_watcher = CreateWatcher (app_file, new FileSystemEventHandler (OnAppFileChanged));
 379 #endif
 380                                 } else {
 381                                         app_type = typeof (System.Web.HttpApplication);
 382                                         app_state = new HttpApplicationState ();
 383                                 }
 384                                 needs_init = false;
 385
 386                                 //
 387                                 // Now init the settings
 388                                 //
 389
 390                         }
 391                 }
 392
 393                 //
 394                 // Multiple-threads might hit this one on startup, and we have
 395                 // to delay-initialize until we have the HttpContext
 396                 //
 397                 internal static HttpApplication GetApplication (HttpContext context)
 398                 {
 399                         HttpApplicationFactory factory = theFactory;
 400                         if (factory.needs_init){
 401                                 if (context == null)
 402                                         return null;
 403
 404                                 factory.InitType (context);
 405                                 lock (factory) {
 406                                         if (factory.app_start_needed) {
 407 #if !TARGET_JVM
 408                                                 string bin = HttpRuntime.BinDirectory;
 409                                                 if (Directory.Exists (bin))
 410                                                         bin = Path.Combine (bin, "*.dll");
 411
 412                                                 // We watch bin or bin/*.dll if the directory exists
 413                                                 factory.bin_watcher = CreateWatcher (bin, new FileSystemEventHandler (factory.OnAppFileChanged));
 414 #endif
 415                                                 factory.FireOnAppStart (context);
 416                                                 factory.app_start_needed = false;
 417                                         }
 418                                 }
 419                         }
 420
 421                         lock (factory.available) {
 422                                 if (factory.available.Count > 0)
 423                                         return (HttpApplication) factory.available.Pop ();
 424                         }
 425
 426                         HttpApplication app = (HttpApplication) Activator.CreateInstance (factory.app_type, true);
 427
 428                         return app;
 429                 }
 430
 431                 // The lock is in InvokeSessionEnd
 432                 static HttpApplication GetApplicationForSessionEnd ()
 433                 {
 434                         HttpApplicationFactory factory = theFactory;
 435                         if (factory.available_for_end.Count > 0)
 436                                 return (HttpApplication) factory.available_for_end.Pop ();
 437
 438                         HttpApplication app = (HttpApplication) Activator.CreateInstance (factory.app_type, true);
 439                         app.InitOnce (false);
 440
 441                         return app;
 442                 }
 443
 444                 internal static void RecycleForSessionEnd (HttpApplication app)
 445                 {
 446                         HttpApplicationFactory factory = theFactory;
 447                         lock (factory.available_for_end) {
 448                                 if (factory.available_for_end.Count < 32)
 449                                         factory.available_for_end.Push (app);
 450                                 else
 451                                         app.Dispose ();
 452                         }
 453                 }
 454
 455                 internal static void Recycle (HttpApplication app)
 456                 {
 457                         HttpApplicationFactory factory = theFactory;
 458                         lock (factory.available) {
 459                                 if (factory.available.Count < 32)
 460                                         factory.available.Push (app);
 461                                 else
 462                                         app.Dispose ();
 463                         }
 464                 }
 465         }
 466 }
 467