mcs/class/System.ServiceModel/System.ServiceModel/ServiceHostBase.cs

   1 //
   2 // ServiceHostBase.cs
   3 //
   4 // Author:
   5 //      Atsushi Enomoto <atsushi@ximian.com>
   6 //
   7 // Copyright (C) 2005-2006 Novell, Inc.  http://www.novell.com
   8 //
   9 // Permission is hereby granted, free of charge, to any person obtaining
  10 // a copy of this software and associated documentation files (the
  11 // "Software"), to deal in the Software without restriction, including
  12 // without limitation the rights to use, copy, modify, merge, publish,
  13 // distribute, sublicense, and/or sell copies of the Software, and to
  14 // permit persons to whom the Software is furnished to do so, subject to
  15 // the following conditions:
  16 //
  17 // The above copyright notice and this permission notice shall be
  18 // included in all copies or substantial portions of the Software.
  19 //
  20 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  21 // EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  22 // MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  23 // NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
  24 // LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  25 // OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  26 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  27 //
  28 using System;
  29 using System.Collections.Generic;
  30 using System.Collections.ObjectModel;
  31 using System.ServiceModel.Channels;
  32 using System.ServiceModel.Configuration;
  33 using System.ServiceModel.Description;
  34 using System.ServiceModel.Dispatcher;
  35 using System.ServiceModel.Security;
  36 using System.Reflection;
  37
  38 namespace System.ServiceModel
  39 {
  40         public abstract class ServiceHostBase
  41                 : CommunicationObject, IExtensibleObject<ServiceHostBase>, IDisposable
  42         {
  43                 ServiceCredentials credentials;
  44                 ServiceDescription description;
  45                 UriSchemeKeyedCollection base_addresses;
  46                 TimeSpan open_timeout, close_timeout, instance_idle_timeout;
  47                 ServiceThrottle throttle;
  48                 List<InstanceContext> contexts;
  49                 ReadOnlyCollection<InstanceContext> exposed_contexts;
  50                 ChannelDispatcherCollection channel_dispatchers;
  51                 IDictionary<string,ContractDescription> contracts;
  52                 int flow_limit = int.MaxValue;
  53                 IExtensionCollection<ServiceHostBase> extensions;
  54
  55                 protected ServiceHostBase ()
  56                 {
  57                         open_timeout = DefaultOpenTimeout;
  58                         close_timeout = DefaultCloseTimeout;
  59
  60                         credentials = new ServiceCredentials ();
  61                         throttle = new ServiceThrottle ();
  62                         contexts = new List<InstanceContext> ();
  63                         exposed_contexts = new ReadOnlyCollection<InstanceContext> (contexts);
  64                         channel_dispatchers = new ChannelDispatcherCollection (this);
  65                 }
  66
  67                 public event EventHandler<UnknownMessageReceivedEventArgs>
  68                         UnknownMessageReceived;
  69
  70                 internal void OnUnknownMessageReceived (Message message)
  71                 {
  72                         if (UnknownMessageReceived != null)
  73                                 UnknownMessageReceived (this, new UnknownMessageReceivedEventArgs (message));
  74                         else
  75                                 // FIXME: better be logged
  76                                 throw new EndpointNotFoundException (String.Format ("The request message has the target '{0}' with action '{1}' which is not reachable in this service contract", message.Headers.To, message.Headers.Action));
  77                 }
  78
  79                 public ReadOnlyCollection<Uri> BaseAddresses {
  80                         get { return new ReadOnlyCollection<Uri> (base_addresses.InternalItems); }
  81                 }
  82
  83                 internal Uri CreateUri (string sheme, Uri relatieUri) {
  84                         Uri baseUri = base_addresses.Contains (sheme) ? base_addresses [sheme] : null;
  85
  86                         if (relatieUri == null)
  87                                 return baseUri;
  88                         if (relatieUri.IsAbsoluteUri)
  89                                 return relatieUri;
  90                         if (baseUri == null)
  91                                 return null;
  92                         return new Uri (baseUri, relatieUri);
  93                 }
  94
  95                 public ChannelDispatcherCollection ChannelDispatchers {
  96                         get { return channel_dispatchers; }
  97                 }
  98
  99                 public ServiceAuthorizationBehavior Authorization {
 100                         get;
 101                         private set;
 102                 }
 103
 104                 [MonoTODO]
 105                 public ServiceCredentials Credentials {
 106                         get { return credentials; }
 107                 }
 108
 109                 public ServiceDescription Description {
 110                         get { return description; }
 111                 }
 112
 113                 protected IDictionary<string,ContractDescription> ImplementedContracts {
 114                         get { return contracts; }
 115                 }
 116
 117                 [MonoTODO]
 118                 public IExtensionCollection<ServiceHostBase> Extensions {
 119                         get {
 120                                 if (extensions == null)
 121                                         extensions = new ExtensionCollection<ServiceHostBase> (this);
 122                                 return extensions;
 123                         }
 124                 }
 125
 126                 protected internal override TimeSpan DefaultCloseTimeout {
 127                         get { return DefaultCommunicationTimeouts.Instance.CloseTimeout; }
 128                 }
 129
 130                 protected internal override TimeSpan DefaultOpenTimeout {
 131                         get { return DefaultCommunicationTimeouts.Instance.OpenTimeout; }
 132                 }
 133
 134                 public TimeSpan CloseTimeout {
 135                         get { return close_timeout; }
 136                         set { close_timeout = value; }
 137                 }
 138
 139                 public TimeSpan OpenTimeout {
 140                         get { return open_timeout; }
 141                         set { open_timeout = value; }
 142                 }
 143
 144                 public int ManualFlowControlLimit {
 145                         get { return flow_limit; }
 146                         set { flow_limit = value; }
 147                 }
 148
 149                 public ServiceEndpoint AddServiceEndpoint (
 150                         string implementedContract, Binding binding, string address)
 151                 {
 152                         return AddServiceEndpoint (implementedContract,
 153                                 binding,
 154                                 new Uri (address, UriKind.RelativeOrAbsolute));
 155                 }
 156
 157                 public ServiceEndpoint AddServiceEndpoint (
 158                         string implementedContract, Binding binding,
 159                         string address, Uri listenUri)
 160                 {
 161                         Uri uri = new Uri (address, UriKind.RelativeOrAbsolute);
 162                         return AddServiceEndpoint (
 163                                 implementedContract, binding, uri, uri);
 164                 }
 165
 166                 public ServiceEndpoint AddServiceEndpoint (
 167                         string implementedContract, Binding binding,
 168                         Uri address)
 169                 {
 170                         return AddServiceEndpoint (implementedContract, binding, address, address);
 171                 }
 172
 173                 public ServiceEndpoint AddServiceEndpoint (
 174                         string implementedContract, Binding binding,
 175                         Uri address, Uri listenUri)
 176                 {
 177                         EndpointAddress ea = BuildEndpointAddress (address, binding);
 178                         ContractDescription cd = GetContract (implementedContract);
 179                         if (cd == null)
 180                                 throw new InvalidOperationException (String.Format ("Contract '{0}' was not found in the implemented contracts in this service host.", implementedContract));
 181                         return AddServiceEndpointCore (cd, binding, ea, listenUri);
 182                 }
 183
 184                 Type PopulateType (string typeName)
 185                 {
 186                         Type type = Type.GetType (typeName);
 187                         if (type != null)
 188                                 return type;
 189                         foreach (ContractDescription cd in ImplementedContracts.Values) {
 190                                 type = cd.ContractType.Assembly.GetType (typeName);
 191                                 if (type != null)
 192                                         return type;
 193                         }
 194                         return null;
 195                 }
 196
 197                 ContractDescription GetContract (string typeName)
 198                 {
 199                         //FIXME: hack hack hack
 200                         ImplementedContracts ["IHttpGetHelpPageAndMetadataContract"] =
 201                                 ContractDescription.GetContract (typeof (IHttpGetHelpPageAndMetadataContract));
 202
 203                         // FIXME: As long as I tried, *only* IMetadataExchange
 204                         // is the exception case that does not require full
 205                         // type name. Hence I treat it as a special case.
 206                         if (typeName == ServiceMetadataBehavior.MexContractName) {
 207                                 if (!Description.Behaviors.Contains (typeof (ServiceMetadataBehavior)) && Array.IndexOf (Description.ServiceType.GetInterfaces (), typeof (IMetadataExchange)) < 0)
 208                                         throw new InvalidOperationException (
 209                                                 "Add ServiceMetadataBehavior to the ServiceHost to add a endpoint for IMetadataExchange contract.");
 210
 211                                 ImplementedContracts [ServiceMetadataBehavior.MexContractName] =
 212                                         ContractDescription.GetContract (typeof (IMetadataExchange));
 213
 214                                 foreach (ContractDescription cd in ImplementedContracts.Values)
 215                                         if (cd.ContractType == typeof (IMetadataExchange))
 216                                                 return cd;
 217                                 return null;
 218                         }
 219
 220                         Type type = PopulateType (typeName);
 221                         if (type == null)
 222                                 return null;
 223
 224                         foreach (ContractDescription cd in ImplementedContracts.Values) {
 225                                 // FIXME: This check is a negative side effect
 226                                 // of the above hack.
 227                                 if (cd.ContractType == typeof (IMetadataExchange))
 228                                         continue;
 229
 230                                 if (cd.ContractType == type ||
 231                                     cd.ContractType.IsSubclassOf (type) ||
 232                                     type.IsInterface && cd.ContractType.GetInterface (type.FullName) == type)
 233                                         return cd;
 234                         }
 235                         return null;
 236                 }
 237
 238                 internal EndpointAddress BuildEndpointAddress (Uri address, Binding binding)
 239                 {
 240                         if (!address.IsAbsoluteUri) {
 241                                 // Find a Base address with matching scheme,
 242                                 // and build new absolute address
 243                                 if (!base_addresses.Contains (binding.Scheme))
 244                                         throw new InvalidOperationException (String.Format ("Could not find base address that matches Scheme {0} for endpoint {1}", binding.Scheme, binding.Name));
 245
 246                                 Uri baseaddr = base_addresses [binding.Scheme];
 247
 248                                 if (!baseaddr.AbsoluteUri.EndsWith ("/"))
 249                                         baseaddr = new Uri (baseaddr.AbsoluteUri + "/");
 250                                 address = new Uri (baseaddr, address);
 251                         }
 252                         return new EndpointAddress (address);
 253                 }
 254
 255                 internal ServiceEndpoint AddServiceEndpointCore (
 256                         ContractDescription cd, Binding binding, EndpointAddress address, Uri listenUri)
 257                 {
 258                         foreach (ServiceEndpoint e in Description.Endpoints)
 259                                 if (e.Contract == cd)
 260                                         return e;
 261                         ServiceEndpoint se = new ServiceEndpoint (cd, binding, address);
 262                         se.ListenUri = listenUri.IsAbsoluteUri ? listenUri : new Uri (address.Uri, listenUri);
 263                         Description.Endpoints.Add (se);
 264                         return se;
 265                 }
 266
 267                 [MonoTODO]
 268                 protected virtual void ApplyConfiguration ()
 269                 {
 270                         if (Description == null)
 271                                 throw new InvalidOperationException ("ApplyConfiguration requires that the Description property be initialized. Either provide a valid ServiceDescription in the CreateDescription method or override the ApplyConfiguration method to provide an alternative implementation");
 272
 273                         ServiceElement service = GetServiceElement ();
 274
 275                         //TODO: Should we call here LoadServiceElement ?
 276                         if (service != null) {
 277
 278                                 //base addresses
 279                                 HostElement host = service.Host;
 280                                 foreach (BaseAddressElement baseAddress in host.BaseAddresses) {
 281                                         this.base_addresses.Add (new Uri (baseAddress.BaseAddress));
 282                                 }
 283
 284                                 // services
 285                                 foreach (ServiceEndpointElement endpoint in service.Endpoints) {
 286                                         // FIXME: consider BindingName as well
 287                                         ServiceEndpoint se = AddServiceEndpoint (
 288                                                 endpoint.Contract,
 289                                                 ConfigUtil.CreateBinding (endpoint.Binding, endpoint.BindingConfiguration),
 290                                                 endpoint.Address.ToString ());
 291                                 }
 292                                 // behaviors
 293                                 // TODO: use EvaluationContext of ServiceElement.
 294                                 ServiceBehaviorElement behavior = ConfigUtil.BehaviorsSection.ServiceBehaviors.Find (service.BehaviorConfiguration);
 295                                 if (behavior != null) {
 296                                         for (int i = 0; i < behavior.Count; i++) {
 297                                                 BehaviorExtensionElement bxel = behavior [i];
 298                                                 IServiceBehavior b = (IServiceBehavior) behavior [i].CreateBehavior ();
 299                                                 if (b != null)
 300                                                         Description.Behaviors.Add (b);
 301                                         }
 302                                 }
 303                         }
 304                         // TODO: consider commonBehaviors here
 305
 306                         // ensure ServiceAuthorizationBehavior
 307                         Authorization = Description.Behaviors.Find<ServiceAuthorizationBehavior> ();
 308                         if (Authorization == null) {
 309                                 Authorization = new ServiceAuthorizationBehavior ();
 310                                 Description.Behaviors.Add (Authorization);
 311                         }
 312
 313                         // ensure ServiceDebugBehavior
 314                         ServiceDebugBehavior debugBehavior = Description.Behaviors.Find<ServiceDebugBehavior> ();
 315                         if (debugBehavior == null) {
 316                                 debugBehavior = new ServiceDebugBehavior ();
 317                                 Description.Behaviors.Add (debugBehavior);
 318                         }
 319                 }
 320
 321                 private ServiceElement GetServiceElement() {
 322                         Type serviceType = Description.ServiceType;
 323                         if (serviceType == null)
 324                                 return null;
 325
 326                         return ConfigUtil.ServicesSection.Services [serviceType.FullName];
 327                 }
 328
 329                 internal ContractDescription GetContract (string name, string ns)
 330                 {
 331                         foreach (ContractDescription d in ImplementedContracts.Values)
 332                                 if (d.Name == name && d.Namespace == ns)
 333                                         return d;
 334                         return null;
 335                 }
 336
 337                 protected abstract ServiceDescription CreateDescription (
 338                         out IDictionary<string,ContractDescription> implementedContracts);
 339
 340                 protected void InitializeDescription (UriSchemeKeyedCollection baseAddresses)
 341                 {
 342                         this.base_addresses = baseAddresses;
 343                         IDictionary<string,ContractDescription> retContracts;
 344                         description = CreateDescription (out retContracts);
 345                         contracts = retContracts;
 346
 347                         ApplyConfiguration ();
 348                 }
 349
 350                 protected virtual void InitializeRuntime ()
 351                 {
 352                         //First validate the description, which should call all behaviors
 353                         //'Validate' method.
 354                         ValidateDescription ();
 355
 356                         //Build all ChannelDispatchers, one dispatcher per user configured EndPoint.
 357                         //We must keep thet ServiceEndpoints as a seperate collection, since the user
 358                         //can change the collection in the description during the behaviors events.
 359                         Dictionary<ServiceEndpoint, ChannelDispatcher> endPointToDispatcher = new Dictionary<ServiceEndpoint,ChannelDispatcher>();
 360                         ServiceEndpoint[] endPoints = new ServiceEndpoint[Description.Endpoints.Count];
 361                         Description.Endpoints.CopyTo (endPoints, 0);
 362                         foreach (ServiceEndpoint se in endPoints) {
 363                                 //Let all behaviors add their binding parameters
 364                                 BindingParameterCollection commonParams =
 365                                         new BindingParameterCollection ();
 366                                 AddBindingParameters (commonParams, se);
 367                                 ChannelDispatcher channel = BuildChannelDispatcher (se, commonParams);
 368                                 ChannelDispatchers.Add (channel);
 369                                 endPointToDispatcher[se] = channel;
 370                         }
 371
 372                         //After the ChannelDispatchers are created, and attached to the service host
 373                         //Apply dispatching behaviors.
 374                         foreach (IServiceBehavior b in Description.Behaviors)
 375                                 b.ApplyDispatchBehavior (Description, this);
 376
 377                         foreach(KeyValuePair<ServiceEndpoint, ChannelDispatcher> val in endPointToDispatcher)
 378                                 ApplyDispatchBehavior(val.Value, val.Key);
 379                 }
 380
 381                 private void ValidateDescription ()
 382                 {
 383                         foreach (IServiceBehavior b in Description.Behaviors)
 384                                 b.Validate (Description, this);
 385                         foreach (ServiceEndpoint endPoint in Description.Endpoints)
 386                                 endPoint.Validate ();
 387                 }
 388
 389                 private void ApplyDispatchBehavior (ChannelDispatcher dispatcher, ServiceEndpoint endPoint) {
 390                         foreach (IContractBehavior b in endPoint.Contract.Behaviors)
 391                                 b.ApplyDispatchBehavior (endPoint.Contract, endPoint, dispatcher.Endpoints[0].DispatchRuntime);
 392                         foreach (IEndpointBehavior b in endPoint.Behaviors)
 393                                 b.ApplyDispatchBehavior (endPoint, dispatcher.Endpoints [0]);
 394                         foreach (OperationDescription operation in endPoint.Contract.Operations) {
 395                                 foreach (IOperationBehavior b in operation.Behaviors)
 396                                         b.ApplyDispatchBehavior (operation, dispatcher.Endpoints [0].DispatchRuntime.Operations [operation.Name]);
 397                         }
 398
 399                 }
 400
 401                 internal ChannelDispatcher BuildChannelDispatcher (ServiceEndpoint se, BindingParameterCollection commonParams)
 402                 {
 403                         //User the binding parameters to build the channel listener and Dispatcher
 404                         IChannelListener lf = BuildListener (se, commonParams);
 405                         ChannelDispatcher cd = new ChannelDispatcher (
 406                                 lf, se.Binding.Name);
 407                         cd.InitializeServiceEndpoint (Description.ServiceType, se);
 408                         return cd;
 409                 }
 410
 411                 private void AddBindingParameters (BindingParameterCollection commonParams, ServiceEndpoint endPoint) {
 412
 413                         commonParams.Add (ChannelProtectionRequirements.CreateFromContract (endPoint.Contract));
 414                         foreach (IServiceBehavior b in Description.Behaviors)
 415                                 b.AddBindingParameters (Description, this, Description.Endpoints, commonParams);
 416
 417                         foreach (IContractBehavior b in endPoint.Contract.Behaviors)
 418                                 b.AddBindingParameters (endPoint.Contract, endPoint, commonParams);
 419                         foreach (IEndpointBehavior b in endPoint.Behaviors)
 420                                 b.AddBindingParameters (endPoint, commonParams);
 421                         foreach (OperationDescription operation in endPoint.Contract.Operations) {
 422                                 foreach (IOperationBehavior b in operation.Behaviors)
 423                                         b.AddBindingParameters (operation, commonParams);
 424                         }
 425                 }
 426
 427                 [MonoTODO]
 428                 protected void LoadConfigurationSection (ServiceElement element)
 429                 {
 430                         ServicesSection services = ConfigUtil.ServicesSection;
 431                 }
 432
 433                 void DoOpen (TimeSpan timeout)
 434                 {
 435                         foreach (var cd in ChannelDispatchers) {
 436                                 cd.Open (timeout);
 437                                 // This is likely hack.
 438                                 if (cd is ChannelDispatcher)
 439                                         ((ChannelDispatcher) cd).StartLoop ();
 440                         }
 441                 }
 442
 443                 IChannelListener BuildListener (ServiceEndpoint se,
 444                         BindingParameterCollection pl)
 445                 {
 446                         Binding b = se.Binding;
 447                         if (b.CanBuildChannelListener<IReplySessionChannel> (pl))
 448                                 return b.BuildChannelListener<IReplySessionChannel> (se.ListenUri, "", se.ListenUriMode, pl);
 449                         if (b.CanBuildChannelListener<IReplyChannel> (pl))
 450                                 return b.BuildChannelListener<IReplyChannel> (se.ListenUri, "", se.ListenUriMode, pl);
 451                         if (b.CanBuildChannelListener<IInputSessionChannel> (pl))
 452                                 return b.BuildChannelListener<IInputSessionChannel> (se.ListenUri, "", se.ListenUriMode, pl);
 453                         if (b.CanBuildChannelListener<IInputChannel> (pl))
 454                                 return b.BuildChannelListener<IInputChannel> (se.ListenUri, "", se.ListenUriMode, pl);
 455
 456                         if (b.CanBuildChannelListener<IDuplexChannel> (pl))
 457                                 return b.BuildChannelListener<IDuplexChannel> (se.ListenUri, "", se.ListenUriMode, pl);
 458                         if (b.CanBuildChannelListener<IDuplexSessionChannel> (pl))
 459                                 return b.BuildChannelListener<IDuplexSessionChannel> (se.ListenUri, "", se.ListenUriMode, pl);
 460                         throw new InvalidOperationException ("None of the listener channel types is supported");
 461                 }
 462
 463                 [MonoTODO]
 464                 protected override sealed void OnAbort ()
 465                 {
 466                 }
 467
 468                 Action<TimeSpan> close_delegate;
 469                 Action<TimeSpan> open_delegate;
 470
 471                 protected override sealed IAsyncResult OnBeginClose (
 472                         TimeSpan timeout, AsyncCallback callback, object state)
 473                 {
 474                         if (close_delegate != null)
 475                                 close_delegate = new Action<TimeSpan> (OnClose);
 476                         return close_delegate.BeginInvoke (timeout, callback, state);
 477                 }
 478
 479                 protected override sealed IAsyncResult OnBeginOpen (
 480                         TimeSpan timeout, AsyncCallback callback, object state)
 481                 {
 482                         if (open_delegate == null)
 483                                 open_delegate = new Action<TimeSpan> (OnOpen);
 484                         return open_delegate.BeginInvoke (timeout, callback, state);
 485                 }
 486
 487                 protected override void OnClose (TimeSpan timeout)
 488                 {
 489                         DateTime start = DateTime.Now;
 490                         ReleasePerformanceCounters ();
 491                         List<ChannelDispatcherBase> l = new List<ChannelDispatcherBase> (ChannelDispatchers);
 492                         foreach (ChannelDispatcherBase e in l) {
 493                                 try {
 494                                         TimeSpan ts = timeout - (DateTime.Now - start);
 495                                         if (ts < TimeSpan.Zero)
 496                                                 e.Abort ();
 497                                         else
 498                                                 e.Close (ts);
 499                                 } catch (Exception ex) {
 500                                         Console.WriteLine ("ServiceHostBase failed to close the channel dispatcher:");
 501                                         Console.WriteLine (ex);
 502                                 }
 503                         }
 504                 }
 505
 506                 protected override sealed void OnOpen (TimeSpan timeout)
 507                 {
 508                         InitializeRuntime ();
 509                         DoOpen (timeout);
 510                 }
 511
 512                 protected override void OnEndClose (IAsyncResult result)
 513                 {
 514                         if (close_delegate == null)
 515                                 throw new InvalidOperationException ("Async close operation has not started");
 516                         close_delegate.EndInvoke (result);
 517                 }
 518
 519                 protected override sealed void OnEndOpen (IAsyncResult result)
 520                 {
 521                         if (open_delegate == null)
 522                                 throw new InvalidOperationException ("Aync open operation has not started");
 523                         open_delegate.EndInvoke (result);
 524                 }
 525
 526                 protected override void OnOpened ()
 527                 {
 528                 }
 529
 530                 [MonoTODO]
 531                 protected void ReleasePerformanceCounters ()
 532                 {
 533                 }
 534
 535                 void IDisposable.Dispose ()
 536                 {
 537                         Close ();
 538                 }
 539
 540                 /*
 541                 class SyncMethodInvoker : IOperationInvoker
 542                 {
 543                         readonly MethodInfo _methodInfo;
 544                         public SyncMethodInvoker (MethodInfo methodInfo) {
 545                                 _methodInfo = methodInfo;
 546                         }
 547
 548                         #region IOperationInvoker Members
 549
 550                         public bool IsSynchronous {
 551                                 get { return true; }
 552                         }
 553
 554                         public object [] AllocateParameters () {
 555                                 return new object [_methodInfo.GetParameters ().Length];
 556                         }
 557
 558                         public object Invoke (object instance, object [] parameters)
 559             {
 560                                 return _methodInfo.Invoke (instance, parameters);
 561                         }
 562
 563                         public IAsyncResult InvokeBegin (object instance, object [] inputs, AsyncCallback callback, object state) {
 564                                 throw new NotSupportedException ();
 565                         }
 566
 567                         public object InvokeEnd (object instance, out object [] outputs, IAsyncResult result) {
 568                                 throw new NotSupportedException ();
 569                         }
 570
 571                         #endregion
 572                 }
 573
 574                 class AsyncMethodInvoker : IOperationInvoker
 575                 {
 576                         readonly MethodInfo _beginMethodInfo, _endMethodInfo;
 577                         public AsyncMethodInvoker (MethodInfo beginMethodInfo, MethodInfo endMethodInfo) {
 578                                 _beginMethodInfo = beginMethodInfo;
 579                                 _endMethodInfo = endMethodInfo;
 580                         }
 581
 582                         #region IOperationInvoker Members
 583
 584                         public bool IsSynchronous {
 585                                 get { return false; }
 586                         }
 587
 588                         public object [] AllocateParameters () {
 589                                 return new object [_beginMethodInfo.GetParameters ().Length - 2 + _endMethodInfo.GetParameters().Length-1];
 590                         }
 591
 592                         public object Invoke (object instance, object [] parameters) {
 593                                 throw new NotImplementedException ("Can't invoke async method synchronously");
 594                                 //BUGBUG: need to differentiate between input and output parameters.
 595                                 IAsyncResult asyncResult = InvokeBegin(instance, parameters, delegate(IAsyncResult ignore) { }, null);
 596                                 asyncResult.AsyncWaitHandle.WaitOne();
 597                                 return InvokeEnd(instance, out parameters, asyncResult);
 598                         }
 599
 600                         public IAsyncResult InvokeBegin (object instance, object [] inputs, AsyncCallback callback, object state) {
 601                                 if (inputs.Length + 2 != _beginMethodInfo.GetParameters ().Length)
 602                                         throw new ArgumentException ("Wrong number of input parameters");
 603                                 object [] fullargs = new object [_beginMethodInfo.GetParameters ().Length];
 604                                 Array.Copy (inputs, fullargs, inputs.Length);
 605                                 fullargs [inputs.Length] = callback;
 606                                 fullargs [inputs.Length + 1] = state;
 607                                 return (IAsyncResult) _beginMethodInfo.Invoke (instance, fullargs);
 608                         }
 609
 610                         public object InvokeEnd (object instance, out object [] outputs, IAsyncResult asyncResult) {
 611                                 outputs = new object [_endMethodInfo.GetParameters ().Length - 1];
 612                                 object [] fullargs = new object [_endMethodInfo.GetParameters ().Length];
 613                                 fullargs [outputs.Length] = asyncResult;
 614                                 object result = _endMethodInfo.Invoke (instance, fullargs);
 615                                 Array.Copy (fullargs, outputs, outputs.Length);
 616                                 return result;
 617                         }
 618
 619                         #endregion
 620                 }
 621                 */
 622         }
 623
 624 }