mcs/class/referencesource/System.Workflow.Runtime/Hosting/WorkflowWebHostingModule.cs

   1 /*******************************************************************************
   2 // Copyright (C) 2000-2001 Microsoft Corporation.  All rights reserved.
   3 //
   4 // CONTENTS
   5 //     Workflow Web Hosting Module.
   6
   7 // DESCRIPTION
   8 //      Implementation of Workflow Web Host Module.
   9
  10 // REVISIONS
  11 // Date          Ver     By           Remarks
  12 // ~~~~~~~~~~    ~~~     ~~~~~~~~     ~~~~~~~~~~~~~~
  13 // 02/22/05      1.0     [....]       Implementation.
  14  * ****************************************************************************/
  15
  16 #region Using directives
  17
  18 using System;
  19 using System.Collections;
  20 using System.Collections.Generic;
  21 using System.Text;
  22 using System.Diagnostics;
  23 using System.Web;
  24 using System.Collections.Specialized;
  25 using System.Threading;
  26
  27 #endregion
  28
  29 namespace System.Workflow.Runtime.Hosting
  30 {
  31     /// <summary>
  32     /// Cookie based rotuing module implementation
  33     /// </summary>
  34     [Obsolete("The System.Workflow.* types are deprecated.  Instead, please use the new types from System.Activities.*")]
  35     public sealed class WorkflowWebHostingModule : IHttpModule
  36     {
  37         HttpApplication currentApplication;
  38
  39         public WorkflowWebHostingModule()
  40         {
  41             WorkflowTrace.Host.TraceEvent(TraceEventType.Information, 0, "Workflow Web Hosting Module Created");
  42         }
  43
  44         /// <summary>
  45         /// IHttpModule.Init()
  46         /// </summary>
  47         /// <param name="application"></param>
  48         void IHttpModule.Init(HttpApplication application)
  49         {
  50             WorkflowTrace.Host.TraceEvent(TraceEventType.Information, 0, "Workflow Web Hosting Module Initialized");
  51
  52             this.currentApplication = application;
  53
  54             //Listen for Acquire and ReleaseRequestState event
  55             application.ReleaseRequestState += this.OnReleaseRequestState;
  56             application.AcquireRequestState += this.OnAcquireRequestState;
  57         }
  58
  59         void IHttpModule.Dispose()
  60         {
  61
  62         }
  63
  64         void OnAcquireRequestState(Object sender, EventArgs e)
  65         {
  66             //Performs Cookie based routing.
  67             WorkflowTrace.Host.TraceEvent(TraceEventType.Information, 0, "WebHost Module Routing Begin");
  68
  69             HttpCookie routingCookie = HttpContext.Current.Request.Cookies.Get("WF_WorkflowInstanceId");
  70
  71             if (routingCookie != null)
  72             {
  73                 HttpContext.Current.Items.Add("__WorkflowInstanceId__", new Guid(routingCookie.Value));
  74             }
  75             //else no routing information found, it could be activation request or non workflow based request.
  76         }
  77
  78         void OnReleaseRequestState(Object sender, EventArgs e)
  79         {
  80             //Saves cookie back to client.
  81             HttpCookie cookie = HttpContext.Current.Request.Cookies.Get("WF_WorkflowInstanceId");
  82
  83             if (cookie == null)
  84             {
  85                 cookie = new HttpCookie("WF_WorkflowInstanceId");
  86                 Object workflowInstanceId = HttpContext.Current.Items["__WorkflowInstanceId__"];
  87
  88                 if (workflowInstanceId != null)
  89                 {
  90                     cookie.Value = workflowInstanceId.ToString();
  91                     HttpContext.Current.Response.Cookies.Add(cookie);
  92                 }
  93             }
  94         }
  95     }
  96 }