Andreas Erben's posts : VS 2008, Windows Communication Foundation

Cloud Proxy Demo / Simple BizTalk Workflow Services End-to-end demo

Andreas Erben — Thu, 02 Oct 2008 09:55:00 GMT

(German version may be written at a later time / Deutsche Version wird gegebenenfalls später geschrieben)

This post combines several concepts from several posts about BizTalk Workflow Services. You should read the intro, about flow control, about send&receive activities and about the little trick to hide some code in conditions. Additionally we will showcase binding of properties in BizTalk Workflow Services.

What shall be achieved?

We want a workflow instance to communicate with a service and be called back by the service. Then the workflow should do something and wait for the client to fetch the result of the work done.

Some challenges:

How to get the WorkflowInstanceId to the service?
How to get information back to the workflow?
How to pass the information from one activity in the workflow to another activity?
How to get the information back to the service?

Challenge 1: How to get the WorkflowInstanceId to the service?

There is currently no out-of-the-box way to access the WorkflowInstanceId and there is no "setter" activity to store a value somewhere. To do this, we will use the technique described in here, where we hide code in conditions to send information via the CloudServiceBusSend activity to the service.

We will use the following condition for that.

System.Convert.ToBoolean(((System.ServiceBus.Workflow.CloudServiceBusSend) this.GetActivityByName("cloudServiceBusSend1") ).GetType().GetProperty("Body").SetValue(this.GetActivityByName("cloudServiceBusSend1"), "<Echo xmlns='http://samples.microsoft.com/ServiceModel/Relay/'><text></text> </Echo>".Insert(69, this.WorkflowInstanceId.ToString()), null)) || True

Note that this condition results in an Xml-string that is longer than 8192 characters. You will have to strip whitespace from that Xml-string to be able to upload it to BizTalk Workflow Services.

Challenge 2: How to get information back to the workflow?

Fortunately we received the InstanceId, now we need to tell the workflow that we want it to do something for us. Unfortunately CloudServiceBusSend so far does not work with returned values. So: The only way to call the workflow is through the CloudHttpReceive activity and we need the InstanceId to call the proper instance. Using the CloudHttpReceive was demonstrated here.

Challenge 3: How to pass the information from one activity in the workflow to another activity?

As mentioned, we have no activities for getting/setting or manipulating data. We could either employ the previously mentioned trick to hide some code in conditions or we can use property binding. We will do the latter.

We bind the request property of a CloudHttpReceive activity to the URL property of a CloudHttpSend activity. So, the URL of the CloudHttpSend will be "filled" by the incoming WebHttpRequest and when CloudHttpSend gets executed it will request data from the URL that was supplied externally.

Activity=cloudHttpSend1, Path=URL

The complete activity with activity binding would look like this:

<ns0:CloudHttpReceive Request="{ActivityBind cloudHttpSend1,Path=URL}" x:Name="cloudHttpReceive1" StatusCode="0" Response="Hello" />

Challenge 4: How to get the information back to the service?

To solve that challenge we can either use a CloudServiceBusSend or we can have the service asking the workflow via a CloudHttpReceive activity. We will use CloudHttpReceive in this case because we want the service to "control" when it asks for the result.

The workflow

Now let us look at the complete workflow first

and as Xoml definition:

<SequentialWorkflowActivity x:Class="WorkflowProject1.Workflow1" x:Name="Workflow1" xmlns:ns0="http://schemas.microsoft.com/2007/11/CloudWorkflowActivityLibrary" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/workflow">
  <ns0:CloudWhile x:Name="cloudWhile1">
    <ns0:CloudWhile.Condition>
      <RuleConditionReference ConditionName="While Condition" />
    </ns0:CloudWhile.Condition>
    <ns0:CloudSequence x:Name="cloudSequence1">
      <ns0:CloudServiceBusSend x:Name="cloudServiceBusSend1" URL="sb://connect.biztalk.net/services/YOURUSERNAMEHERE/EchoService/" Response="" Body="&lt;Echo xmlns='http://samples.microsoft.com/ServiceModel/Relay/'&gt; &lt;text&gt;Original&lt;/text&gt;&lt;/Echo&gt;" Action="http://samples.microsoft.com/ServiceModel/Relay/EchoContract/Echo" ConnectionMode="RelayedDuplexSession" />
      <ns0:CloudHttpReceive Request="{ActivityBind cloudHttpSend1,Path=URL}" x:Name="cloudHttpReceive1" StatusCode="0" Response="Hello" />
      <ns0:CloudHttpSend x:Name="cloudHttpSend1" StatusCode="0" URL="http://www.microsoft.com" Method="GET" Request="{x:Null}" RequestContentType="{x:Null}" Response="{ActivityBind cloudHttpReceive2,Path=Response}" />
      <ns0:CloudHttpReceive Request="{x:Null}" x:Name="cloudHttpReceive2" StatusCode="0" Response="Bye" />
      <ns0:CloudDelay x:Name="cloudDelay1" Timeout="00:00:10" />
    </ns0:CloudSequence>
  </ns0:CloudWhile>
</SequentialWorkflowActivity>

Let's look at the activities from top to bottom.

There is not really anything to say about cloudSequence1.

The cloudWhile1 activity has the condition set as seen in Challenge 1.

The condition is represented by this Xml structure:

<RuleDefinitions xmlns="http://schemas.microsoft.com/winfx/2006/xaml/workflow">
  <RuleDefinitions.Conditions>
    <RuleExpressionCondition Name="While Condition">
      <RuleExpressionCondition.Expression>
        <ns0:CodeBinaryOperatorExpression Operator="BooleanOr" xmlns:ns0="clr-namespace:System.CodeDom;Assembly=System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
          <ns0:CodeBinaryOperatorExpression.Left>
            <ns0:CodeMethodInvokeExpression>
              <ns0:CodeMethodInvokeExpression.Parameters>
                <ns0:CodeMethodInvokeExpression>
                  <ns0:CodeMethodInvokeExpression.Parameters>
                    <ns0:CodeMethodInvokeExpression>
                      <ns0:CodeMethodInvokeExpression.Parameters>
                        <ns0:CodePrimitiveExpression>
                          <ns0:CodePrimitiveExpression.Value>
                            <ns1:String xmlns:ns1="clr-namespace:System;Assembly=mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">cloudServiceBusSend1</ns1:String>
                          </ns0:CodePrimitiveExpression.Value>
                        </ns0:CodePrimitiveExpression>
                      </ns0:CodeMethodInvokeExpression.Parameters>
                      <ns0:CodeMethodInvokeExpression.Method>
                        <ns0:CodeMethodReferenceExpression MethodName="GetActivityByName">
                          <ns0:CodeMethodReferenceExpression.TargetObject>
                            <ns0:CodeThisReferenceExpression />
                          </ns0:CodeMethodReferenceExpression.TargetObject>
                        </ns0:CodeMethodReferenceExpression>
                      </ns0:CodeMethodInvokeExpression.Method>
                    </ns0:CodeMethodInvokeExpression>
                    <ns0:CodeMethodInvokeExpression>
                      <ns0:CodeMethodInvokeExpression.Parameters>
                        <ns0:CodePrimitiveExpression>
                          <ns0:CodePrimitiveExpression.Value>
                            <ns1:Int32 xmlns:ns1="clr-namespace:System;Assembly=mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">69</ns1:Int32>
                          </ns0:CodePrimitiveExpression.Value>
                        </ns0:CodePrimitiveExpression>
                        <ns0:CodeMethodInvokeExpression>
                          <ns0:CodeMethodInvokeExpression.Method>
                            <ns0:CodeMethodReferenceExpression MethodName="ToString">
                              <ns0:CodeMethodReferenceExpression.TargetObject>
                                <ns0:CodePropertyReferenceExpression PropertyName="WorkflowInstanceId">
                                  <ns0:CodePropertyReferenceExpression.TargetObject>
                                    <ns0:CodeThisReferenceExpression />
                                  </ns0:CodePropertyReferenceExpression.TargetObject>
                                </ns0:CodePropertyReferenceExpression>
                              </ns0:CodeMethodReferenceExpression.TargetObject>
                            </ns0:CodeMethodReferenceExpression>
                          </ns0:CodeMethodInvokeExpression.Method>
                        </ns0:CodeMethodInvokeExpression>
                      </ns0:CodeMethodInvokeExpression.Parameters>
                      <ns0:CodeMethodInvokeExpression.Method>
                        <ns0:CodeMethodReferenceExpression MethodName="Insert">
                          <ns0:CodeMethodReferenceExpression.TargetObject>
                            <ns0:CodePrimitiveExpression>
                              <ns0:CodePrimitiveExpression.Value>
                                <ns1:String xmlns:ns1="clr-namespace:System;Assembly=mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">&lt;Echo xmlns='http://samples.microsoft.com/ServiceModel/Relay/'&gt;&lt;text&gt;&lt;/text&gt; &lt;/Echo&gt;</ns1:String>
                              </ns0:CodePrimitiveExpression.Value>
                            </ns0:CodePrimitiveExpression>
                          </ns0:CodeMethodReferenceExpression.TargetObject>
                        </ns0:CodeMethodReferenceExpression>
                      </ns0:CodeMethodInvokeExpression.Method>
                    </ns0:CodeMethodInvokeExpression>
                    <ns0:CodePrimitiveExpression />
                  </ns0:CodeMethodInvokeExpression.Parameters>
                  <ns0:CodeMethodInvokeExpression.Method>
                    <ns0:CodeMethodReferenceExpression MethodName="SetValue">
                      <ns0:CodeMethodReferenceExpression.TargetObject>
                        <ns0:CodeMethodInvokeExpression>
                          <ns0:CodeMethodInvokeExpression.Parameters>
                            <ns0:CodePrimitiveExpression>
                              <ns0:CodePrimitiveExpression.Value>
                                <ns1:String xmlns:ns1="clr-namespace:System;Assembly=mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">Body</ns1:String>
                              </ns0:CodePrimitiveExpression.Value>
                            </ns0:CodePrimitiveExpression>
                          </ns0:CodeMethodInvokeExpression.Parameters>
                          <ns0:CodeMethodInvokeExpression.Method>
                            <ns0:CodeMethodReferenceExpression MethodName="GetProperty">
                              <ns0:CodeMethodReferenceExpression.TargetObject>
                                <ns0:CodeMethodInvokeExpression>
                                  <ns0:CodeMethodInvokeExpression.Method>
                                    <ns0:CodeMethodReferenceExpression MethodName="GetType">
                                      <ns0:CodeMethodReferenceExpression.TargetObject>
                                        <ns0:CodeCastExpression TargetType="System.ServiceBus.Workflow.CloudServiceBusSend, System.ServiceBus.Workflow, Version=0.12.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
                                          <ns0:CodeCastExpression.Expression>
                                            <ns0:CodeMethodInvokeExpression>
                                              <ns0:CodeMethodInvokeExpression.Parameters>
                                                <ns0:CodePrimitiveExpression>
                                                  <ns0:CodePrimitiveExpression.Value>
                                                    <ns1:String xmlns:ns1="clr-namespace:System;Assembly=mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">cloudServiceBusSend1</ns1:String>
                                                  </ns0:CodePrimitiveExpression.Value>
                                                </ns0:CodePrimitiveExpression>
                                              </ns0:CodeMethodInvokeExpression.Parameters>
                                              <ns0:CodeMethodInvokeExpression.Method>
                                                <ns0:CodeMethodReferenceExpression MethodName="GetActivityByName">
                                                  <ns0:CodeMethodReferenceExpression.TargetObject>
                                                    <ns0:CodeThisReferenceExpression />
                                                  </ns0:CodeMethodReferenceExpression.TargetObject>
                                                </ns0:CodeMethodReferenceExpression>
                                              </ns0:CodeMethodInvokeExpression.Method>
                                            </ns0:CodeMethodInvokeExpression>
                                          </ns0:CodeCastExpression.Expression>
                                        </ns0:CodeCastExpression>
                                      </ns0:CodeMethodReferenceExpression.TargetObject>
                                    </ns0:CodeMethodReferenceExpression>
                                  </ns0:CodeMethodInvokeExpression.Method>
                                </ns0:CodeMethodInvokeExpression>
                              </ns0:CodeMethodReferenceExpression.TargetObject>
                            </ns0:CodeMethodReferenceExpression>
                          </ns0:CodeMethodInvokeExpression.Method>
                        </ns0:CodeMethodInvokeExpression>
                      </ns0:CodeMethodReferenceExpression.TargetObject>
                    </ns0:CodeMethodReferenceExpression>
                  </ns0:CodeMethodInvokeExpression.Method>
                </ns0:CodeMethodInvokeExpression>
              </ns0:CodeMethodInvokeExpression.Parameters>
              <ns0:CodeMethodInvokeExpression.Method>
                <ns0:CodeMethodReferenceExpression MethodName="ToBoolean">
                  <ns0:CodeMethodReferenceExpression.TargetObject>
                    <ns0:CodeTypeReferenceExpression Type="System.Convert, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" />
                  </ns0:CodeMethodReferenceExpression.TargetObject>
                </ns0:CodeMethodReferenceExpression>
              </ns0:CodeMethodInvokeExpression.Method>
            </ns0:CodeMethodInvokeExpression>
          </ns0:CodeBinaryOperatorExpression.Left>
          <ns0:CodeBinaryOperatorExpression.Right>
            <ns0:CodePrimitiveExpression>
              <ns0:CodePrimitiveExpression.Value>
                <ns1:Boolean xmlns:ns1="clr-namespace:System;Assembly=mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">true</ns1:Boolean>
              </ns0:CodePrimitiveExpression.Value>
            </ns0:CodePrimitiveExpression>
          </ns0:CodeBinaryOperatorExpression.Right>
        </ns0:CodeBinaryOperatorExpression>
      </RuleExpressionCondition.Expression>
    </RuleExpressionCondition>
  </RuleDefinitions.Conditions>
</RuleDefinitions>

For "copy/paste" purposes, here is the whitespace-stripped Xml-representation:

<RuleDefinitions xmlns="http://schemas.microsoft.com/winfx/2006/xaml/workflow"><RuleDefinitions.Conditions><RuleExpressionCondition Name="While Condition"><RuleExpressionCondition.Expression><ns0:CodeBinaryOperatorExpression Operator="BooleanOr" xmlns:ns0="clr-namespace:System.CodeDom;Assembly=System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"><ns0:CodeBinaryOperatorExpression.Left><ns0:CodeMethodInvokeExpression><ns0:CodeMethodInvokeExpression.Parameters><ns0:CodeMethodInvokeExpression><ns0:CodeMethodInvokeExpression.Parameters><ns0:CodeMethodInvokeExpression><ns0:CodeMethodInvokeExpression.Parameters><ns0:CodePrimitiveExpression><ns0:CodePrimitiveExpression.Value><ns1:String xmlns:ns1="clr-namespace:System;Assembly=mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">cloudServiceBusSend1</ns1:String></ns0:CodePrimitiveExpression.Value></ns0:CodePrimitiveExpression></ns0:CodeMethodInvokeExpression.Parameters><ns0:CodeMethodInvokeExpression.Method><ns0:CodeMethodReferenceExpression MethodName="GetActivityByName"><ns0:CodeMethodReferenceExpression.TargetObject><ns0:CodeThisReferenceExpression /></ns0:CodeMethodReferenceExpression.TargetObject></ns0:CodeMethodReferenceExpression></ns0:CodeMethodInvokeExpression.Method></ns0:CodeMethodInvokeExpression><ns0:CodeMethodInvokeExpression><ns0:CodeMethodInvokeExpression.Parameters><ns0:CodePrimitiveExpression><ns0:CodePrimitiveExpression.Value><ns1:Int32 xmlns:ns1="clr-namespace:System;Assembly=mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">69</ns1:Int32></ns0:CodePrimitiveExpression.Value></ns0:CodePrimitiveExpression><ns0:CodeMethodInvokeExpression><ns0:CodeMethodInvokeExpression.Method><ns0:CodeMethodReferenceExpression MethodName="ToString"><ns0:CodeMethodReferenceExpression.TargetObject><ns0:CodePropertyReferenceExpression PropertyName="WorkflowInstanceId"><ns0:CodePropertyReferenceExpression.TargetObject><ns0:CodeThisReferenceExpression /></ns0:CodePropertyReferenceExpression.TargetObject></ns0:CodePropertyReferenceExpression></ns0:CodeMethodReferenceExpression.TargetObject></ns0:CodeMethodReferenceExpression></ns0:CodeMethodInvokeExpression.Method></ns0:CodeMethodInvokeExpression></ns0:CodeMethodInvokeExpression.Parameters><ns0:CodeMethodInvokeExpression.Method><ns0:CodeMethodReferenceExpression MethodName="Insert"><ns0:CodeMethodReferenceExpression.TargetObject><ns0:CodePrimitiveExpression><ns0:CodePrimitiveExpression.Value><ns1:String xmlns:ns1="clr-namespace:System;Assembly=mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">&lt;Echo xmlns='http://samples.microsoft.com/ServiceModel/Relay/'&gt;&lt;text&gt;&lt;/text&gt; &lt;/Echo&gt;</ns1:String></ns0:CodePrimitiveExpression.Value></ns0:CodePrimitiveExpression></ns0:CodeMethodReferenceExpression.TargetObject></ns0:CodeMethodReferenceExpression></ns0:CodeMethodInvokeExpression.Method></ns0:CodeMethodInvokeExpression><ns0:CodePrimitiveExpression /></ns0:CodeMethodInvokeExpression.Parameters><ns0:CodeMethodInvokeExpression.Method><ns0:CodeMethodReferenceExpression MethodName="SetValue"><ns0:CodeMethodReferenceExpression.TargetObject><ns0:CodeMethodInvokeExpression><ns0:CodeMethodInvokeExpression.Parameters><ns0:CodePrimitiveExpression><ns0:CodePrimitiveExpression.Value><ns1:String xmlns:ns1="clr-namespace:System;Assembly=mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">Body</ns1:String></ns0:CodePrimitiveExpression.Value></ns0:CodePrimitiveExpression></ns0:CodeMethodInvokeExpression.Parameters><ns0:CodeMethodInvokeExpression.Method><ns0:CodeMethodReferenceExpression MethodName="GetProperty"><ns0:CodeMethodReferenceExpression.TargetObject><ns0:CodeMethodInvokeExpression><ns0:CodeMethodInvokeExpression.Method><ns0:CodeMethodReferenceExpression MethodName="GetType"><ns0:CodeMethodReferenceExpression.TargetObject><ns0:CodeCastExpression TargetType="System.ServiceBus.Workflow.CloudServiceBusSend, System.ServiceBus.Workflow, Version=0.12.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"><ns0:CodeCastExpression.Expression><ns0:CodeMethodInvokeExpression><ns0:CodeMethodInvokeExpression.Parameters><ns0:CodePrimitiveExpression><ns0:CodePrimitiveExpression.Value><ns1:String xmlns:ns1="clr-namespace:System;Assembly=mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">cloudServiceBusSend1</ns1:String></ns0:CodePrimitiveExpression.Value></ns0:CodePrimitiveExpression></ns0:CodeMethodInvokeExpression.Parameters><ns0:CodeMethodInvokeExpression.Method><ns0:CodeMethodReferenceExpression MethodName="GetActivityByName"><ns0:CodeMethodReferenceExpression.TargetObject><ns0:CodeThisReferenceExpression /></ns0:CodeMethodReferenceExpression.TargetObject></ns0:CodeMethodReferenceExpression></ns0:CodeMethodInvokeExpression.Method></ns0:CodeMethodInvokeExpression></ns0:CodeCastExpression.Expression></ns0:CodeCastExpression></ns0:CodeMethodReferenceExpression.TargetObject></ns0:CodeMethodReferenceExpression></ns0:CodeMethodInvokeExpression.Method></ns0:CodeMethodInvokeExpression></ns0:CodeMethodReferenceExpression.TargetObject></ns0:CodeMethodReferenceExpression></ns0:CodeMethodInvokeExpression.Method></ns0:CodeMethodInvokeExpression></ns0:CodeMethodReferenceExpression.TargetObject></ns0:CodeMethodReferenceExpression></ns0:CodeMethodInvokeExpression.Method></ns0:CodeMethodInvokeExpression></ns0:CodeMethodInvokeExpression.Parameters><ns0:CodeMethodInvokeExpression.Method><ns0:CodeMethodReferenceExpression MethodName="ToBoolean"><ns0:CodeMethodReferenceExpression.TargetObject><ns0:CodeTypeReferenceExpression Type="System.Convert, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" /></ns0:CodeMethodReferenceExpression.TargetObject></ns0:CodeMethodReferenceExpression></ns0:CodeMethodInvokeExpression.Method></ns0:CodeMethodInvokeExpression></ns0:CodeBinaryOperatorExpression.Left><ns0:CodeBinaryOperatorExpression.Right><ns0:CodePrimitiveExpression><ns0:CodePrimitiveExpression.Value><ns1:Boolean xmlns:ns1="clr-namespace:System;Assembly=mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">true</ns1:Boolean></ns0:CodePrimitiveExpression.Value></ns0:CodePrimitiveExpression></ns0:CodeBinaryOperatorExpression.Right></ns0:CodeBinaryOperatorExpression></RuleExpressionCondition.Expression></RuleExpressionCondition></RuleDefinitions.Conditions></RuleDefinitions>

cloudServiceBusSend1 is configured like this with the "Body" property actually at execution time being overwritten by the condition of cloudWhile1.

cloudHttpReceive1 will get data in the "Request" property and put it into the "URL" property of cloudHttpSend1.

cloudHttpSend1 will find it's URL property overwritten by the data received at cloudHttpReceive1. Then it will execute the WebHttpRequest and put the body of the result in the "Response" property of cloudHttpReceive2.

cloudHttpReceive2 looks very empty. The "Response" property however will be overwritten by the data bound in cloudHttpSend1.

cloudDelay1 is configured to wait 10 seconds.

Create this workflow by copy/pasting the Xoml and rules and setting the type name to "SimpleEnd2End".

The service

Now you need to set up the service. To do that work on a copy of Program Files\Microsoft BizTalk Services SDK\Samples\Communication\GettingStarted\Echo.

You will need to modify the file "EchoService.cs".

Modify the "using" statements like this:

using System;
using System.ServiceModel;
using System.Threading;
using System.Net;
using System.IO;
using System.Text;

Copy the methods "CallHttpReceiveActivityWithLogin", "GetTokenGrantingToken" and "CallHttpReceiveActivity" from the code snippet at the bottom of send&receive activities to the class "EchoService".

Modify the "Echo"-method like this:

public string Echo(string text)
{
    Console.WriteLine(text + ":InstanceId received");
    Threading.ThreadStart starter = delegate { HttpCall(text); };
    new Threading.Thread(starter).Start();
    return "nothing to return really";        
}

You see that a new thread will be started with a delegate to HttpCall(text). This is because the service shall continue processing after returning from the "Echo"-method

Add a method "HttpCall" like this:

private void HttpCall(string instanceId)
{
    Console.WriteLine(instanceId+":Thread started");
    string username = "YOURUSERNAME";
    string password = "YOURPASSWORD";
    string workflowTypeName = "SimpleEnd2End";
    string activityName1 = "cloudHttpReceive1";
    string activityName2 = "cloudHttpReceive2";
    string dummyString = "does not matter";
    string urlToGet = "http://www.daenet.eu";
    //wait a bit before the first call
    Thread.Sleep(1000);
    Console.WriteLine(instanceId + ":request "+urlToGet);
    string result1 = CallHttpReceiveActivityWithLogin(
                                urlToGet, username, password,
                                workflowTypeName, activityName1,
                                instanceId);
    //wait a bit before the second call to allow loading of URL
    Thread.Sleep(5000);
    Console.WriteLine(instanceId + ":retrieve data for "
                      + urlToGet);
    string result2 = CallHttpReceiveActivityWithLogin(
                                dummyString, username, password,
                                workflowTypeName, activityName2,
                                instanceId);
    Console.WriteLine(instanceId + ":WebHttpResponse length "
                      + result2.Length);
    Console.WriteLine(instanceId + ":Thread exits");
}

After some initialization this method waits for 1 second and then does a WebHttpRequest to the activity cloudHttpReceive1, sending "http://www.daenet.eu" in the body of the request (which will then overwrite "http://www.microsoft.com" in the cloudHttpSend1 activity). At the same time the workflow in the cloud should continue and retrieve the wanted data. Then it waits another 5 seconds and executes another WebHttpRequest, but this time to the activity cloudHttpReceive2, where it will retrieve the result of what the workflow hopefully loaded meanwhile from the passed URL. Some output is printed to the console and the method and thread exits.
Please note that the workflow itself however will loop endlessly and likely block at some point since it may reach a CloudHttpReceive when there is nobody to send anymore.

For your convenience, the complete code of the modified file "EchoService.cs":

//---------------------------------------------------------------------------------
// Microsoft (R) BizTalk Services
// Software Development Kit
// 
// Copyright (c) Microsoft Corporation. All rights reserved.  
// Copyright (c) of modifications: Andreas Erben
// THIS CODE AND INFORMATION ARE PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, 
// EITHER EXPRESSED OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES 
// OF MERCHANTABILITY AND/OR FITNESS FOR A PARTICULAR PURPOSE. 
//---------------------------------------------------------------------------------
 
namespace System.ServiceBus.Samples
{
    using System;
    using System.ServiceModel;
    using System.Threading;
    using System.Net;
    using System.IO;
    using System.Text;
 
 
    [ServiceBehavior(Name = "EchoService",
        Namespace = "http://samples.microsoft.com/ServiceModel/Relay/")]
    class EchoService : EchoContract
    {
        public string Echo(string text)
        {
            Console.WriteLine(text + ":InstanceId received");
            Threading.ThreadStart starter = delegate { HttpCall(text); };
            new Threading.Thread(starter).Start();
            return "nothing to return really";        
        }
 
        private void HttpCall(string instanceId)
        {
            Console.WriteLine(instanceId+":Thread started");
            string username = "YOURUSERNAME";
            string password = "YOURPASSWORD";
            string workflowTypeName = "SimpleEnd2End";
            string activityName1 = "cloudHttpReceive1";
            string activityName2 = "cloudHttpReceive2";
            string dummyString = "does not matter";
            string urlToGet = "http://www.daenet.eu";
            //wait a bit before the first call
            Thread.Sleep(1000);
            Console.WriteLine(instanceId + ":request "+urlToGet);
            string result1 = CallHttpReceiveActivityWithLogin(
                                        urlToGet, username, password,
                                        workflowTypeName, activityName1,
                                        instanceId);
            //wait a bit before the second call to allow loading of URL
            Thread.Sleep(5000);
            Console.WriteLine(instanceId + ":retrieve data for "
                              + urlToGet);
            string result2 = CallHttpReceiveActivityWithLogin(
                                        dummyString, username, password,
                                        workflowTypeName, activityName2,
                                        instanceId);
            Console.WriteLine(instanceId + ":WebHttpResponse length "
                              + result2.Length);
            Console.WriteLine(instanceId + ":Thread exits");
        }
 
        static string CallHttpReceiveActivityWithLogin(
                    string requestBody, string username, string password,
                    string workflowTypeName, string activityName,
                    string instanceId)
        {
            string token = GetTokenGrantingToken(username, password);
            return CallHttpReceiveActivity(
                                    requestBody, username, token,
                                    workflowTypeName, activityName,
                                    instanceId);
        }
 
        static string GetTokenGrantingToken(string userName, string password)
        {
            string tokenUrl = string.Format(
                "https://{0}/issuetoken.aspx?u={1}&p={2}",
                "identity.biztalk.net",
                userName,
                password);
 
            HttpWebRequest tokenRequest = (HttpWebRequest)WebRequest.Create(tokenUrl);
            HttpWebResponse tokenResponse = (HttpWebResponse)tokenRequest.GetResponse();
 
            using (Stream responseStream = tokenResponse.GetResponseStream())
            {
                byte[] tokenBody = new byte[500];
                int tokenBodyLength = responseStream.Read(tokenBody, 0, 500);
                return Encoding.UTF8.GetString(tokenBody, 0, tokenBodyLength);
            }
        }
 
        static string CallHttpReceiveActivity(
                            string requestBody, string username, string token,
                            string workflowTypeName, string activityName,
                            string instanceId)
        {
            Uri address = new Uri(@"http://workflow.biztalk.net/servicesHttp/"
                        + username + "/workflows/" + workflowTypeName +
                        "/instances/" + instanceId + "/" + activityName);
            HttpWebRequest request = (HttpWebRequest)HttpWebRequest.Create(address);
            //this adds the retrieved token as a header
            request.Headers.Add("X-MS-Identity-Token", token);
            request.Method = "POST";
            request.ContentType = "text/plain";
            //send the body
            byte[] requestBodyBytes = Encoding.UTF8.GetBytes(requestBody);
            request.ContentLength = requestBodyBytes.Length;
            using (Stream requestStream = request.GetRequestStream())
            {
                requestStream.Write(requestBodyBytes, 0, requestBodyBytes.Length);
                requestStream.Flush();
            }
 
            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            using (Stream responseStream = response.GetResponseStream())
            {
 
                using (StreamReader reader = new StreamReader(responseStream,
                                                              Encoding.UTF8))
                {
                    return reader.ReadToEnd();
                }
            }
        }
    }
}

Running the sample

Start the modifed "Echo"-sample that will start-up its self-hosted ServiceBus endpoint.
Create 1 or more instances of the type SimpleEnd2End.
Start the instances of SimpleEnd2End.
Watch the output in the console of the modified "Echo"-sample until you are happy and press enter.

The output for 1 workflow instance:

d81d8ba2-3137-4a6d-aafe-c6c8c5eea1a8:InstanceId received
d81d8ba2-3137-4a6d-aafe-c6c8c5eea1a8:Thread started
d81d8ba2-3137-4a6d-aafe-c6c8c5eea1a8:request http://www.daenet.eu
d81d8ba2-3137-4a6d-aafe-c6c8c5eea1a8:retrieve data for http://www.daenet.eu
d81d8ba2-3137-4a6d-aafe-c6c8c5eea1a8:WebHttpResponse length 28427
d81d8ba2-3137-4a6d-aafe-c6c8c5eea1a8:Thread exits
d81d8ba2-3137-4a6d-aafe-c6c8c5eea1a8:InstanceId received
d81d8ba2-3137-4a6d-aafe-c6c8c5eea1a8:Thread started
d81d8ba2-3137-4a6d-aafe-c6c8c5eea1a8:request http://www.daenet.eu
d81d8ba2-3137-4a6d-aafe-c6c8c5eea1a8:retrieve data for http://www.daenet.eu
d81d8ba2-3137-4a6d-aafe-c6c8c5eea1a8:WebHttpResponse length 28427
d81d8ba2-3137-4a6d-aafe-c6c8c5eea1a8:Thread exits

The output for 2 concurrent workflow instances:

a7874223-e9d1-430c-b0f9-d36baf6d1076:InstanceId received
a7874223-e9d1-430c-b0f9-d36baf6d1076:Thread started
a7874223-e9d1-430c-b0f9-d36baf6d1076:request http://www.daenet.eu
befa13cf-4b4c-4118-82dc-4a94ef288952:InstanceId received
befa13cf-4b4c-4118-82dc-4a94ef288952:Thread started
befa13cf-4b4c-4118-82dc-4a94ef288952:request http://www.daenet.eu
a7874223-e9d1-430c-b0f9-d36baf6d1076:retrieve data for http://www.daenet.eu
befa13cf-4b4c-4118-82dc-4a94ef288952:retrieve data for http://www.daenet.eu
a7874223-e9d1-430c-b0f9-d36baf6d1076:WebHttpResponse length 28427
a7874223-e9d1-430c-b0f9-d36baf6d1076:Thread exits
befa13cf-4b4c-4118-82dc-4a94ef288952:WebHttpResponse length 28427
befa13cf-4b4c-4118-82dc-4a94ef288952:Thread exits
a7874223-e9d1-430c-b0f9-d36baf6d1076:InstanceId received
a7874223-e9d1-430c-b0f9-d36baf6d1076:Thread started
a7874223-e9d1-430c-b0f9-d36baf6d1076:request http://www.daenet.eu
befa13cf-4b4c-4118-82dc-4a94ef288952:InstanceId received
befa13cf-4b4c-4118-82dc-4a94ef288952:Thread started
befa13cf-4b4c-4118-82dc-4a94ef288952:request http://www.daenet.eu
a7874223-e9d1-430c-b0f9-d36baf6d1076:retrieve data for http://www.daenet.eu
befa13cf-4b4c-4118-82dc-4a94ef288952:retrieve data for http://www.daenet.eu
a7874223-e9d1-430c-b0f9-d36baf6d1076:WebHttpResponse length 28427
a7874223-e9d1-430c-b0f9-d36baf6d1076:Thread exits
befa13cf-4b4c-4118-82dc-4a94ef288952:WebHttpResponse length 28427
befa13cf-4b4c-4118-82dc-4a94ef288952:Thread exits

This is part of the actual retrieved data to be found in result2 when breaking after the second call to the workflow:

Note that it will, as seen in the previous blog-post be wrapped in the XML representation of a string object containing the retrieved data. To get the actual data, you would need to parse that XML structure (even though it is a simple parse).

This is all for now, I hope it made BizTalk Workflow Services more "accessible".

Finally some advertisment: If you want to talk to us/me about BizTalk Workflow Services or other exciting technologies or approaches then contact us/me. "face 2 face" logistics are most easy in the US or Europe.

Andreas@Mobility Day 2008, Zagreb, Croatia

Andreas Erben — Sat, 13 Sep 2008 01:10:24 GMT

I had the honor to present at the Mobility Day 2008 in beautiful Zagreb, Croatia on September 9, 2008.

I covered part 2 of a series of two sessions dealing with "best practices" about connecting mobile systems. While the first part, presented by Damir Dobric, dealt with quite advanced connectivity scenarios utilizing WCF and .NET Compact Framework at the core implementation level, my part presented a larger scenario combining a WCF Service Bus and a retry-ing binding together with a cell tower to geo-coordinate service to a multiple-subscriber application.

Find my presentation at this location: http://developers.de/media/p/2857.aspx.

Workaround for problem with BizTalk RFID and .NET 3.5 beta 2 installed on the same machine

Andreas Erben — Wed, 03 Oct 2007 18:44:39 GMT

If you install .NET framework 3.5 beta 2 on the same machine like Microsoft BizTalk RFID, then your RFID Services will not start anymore.

See: http://support.microsoft.com/kb/942521

The reason for this is that the installation of .NET framework 3.5 beta 2 does not leave the DLLs of .NET framework 3.0 alone, but replaces them, introducing at least one bug.

In this case, the System.Runtime.Serialization.dll is replaced, both in
%windir%\Microsoft.Net\Framework\v3.0\Windows Communication Foundation
and in the GAC.

To fix this, you need to retrieve an old version of the System.Runtime.Serialization.dll from a working installation of .NET framework 3.0 and register it in the GAC.
What you do NOT want is version 3.0.4506.590. What you want is for example version 3.0.4506.30. Note however, that this is completely unsupported and that you do this at your own risk and that their might be side effects and incompatibilities with other parts of the system.

Reminder: To install the correct copy in the GAC use this line:
gacutil /f /i System.Runtime.Serialization.dll

This will force an overwrite of the existing System.Runtime.Serialization.dll

You can find gacutil usually in:
%ProgramFiles%\Microsoft SDKs\Windows\6.0\bin\gacutil.exe
or if you installed the full SDK that comes with Visual Studio 2008 Beta 2, in
%ProgramFiles%\Microsoft SDKs\Windows\6.0\bin\gacutil.exe.

Good luck!

WCF designer revisited: Efforts on the way, not coming as part of any product yet

Andreas Erben — Thu, 07 Jun 2007 00:19:46 GMT

Damir recently posted about a WCF designer, or rather that there is no WCF designer yet and it does not seem to be on the immediate roadmap for Orcas / Visual Studio 2008.

Let me look deeper into the promise of the WCF designer..

Chris Smith said in early 2006 he is working on the WCF designer experience. But what are the actual developments we actually see?

1. VS 2005 extensions for .NET Framework 3.0 (WCF & WPF) & VS 2008 ("Orcas")

The "Visual Studio 2005 extensions for .NET Framework 3.0 (WCF & WPF)" have been referred to as "WCF designer" in the blog post "Introducing the <DataContract>" by Thom Robbins. Those features will be available in Visual Studio 2008 (codename: Orcas). They might not "deserve" the name though when comparing with what people actually might expect when hearing "WCF designer".

2. Patterns & Practices: Service Factory

There is speculation that the "Service Factory" from Patterns&Practices will basically contain or be what people will then call "WCF designer". Currently the recent developments are available at Codeplex, check out the newer builds. Check out the Service Factory Blogs.As of the time of the posting though, this does NOT work with Orcas yet.

Taken from Don Smith's blog post "First Service Factory v3 Community Drop" here are two pictures of what to expect

There are newer builds available already.

3. Community effort: DSLFactory Utilities

Last but not least I want to point your attention to the efforts of the French speaking community http://dslfactory.org/. Check out codeplex here: http://www.codeplex.com/DslFactoryUtilities.

They posted how it can look like:

This is synchronized with code.

Not bad at all!

Not part of any product yet

We see various efforts underway inside Microsoft and inside the community, but there is no product yet that will ship anything WCF designer-like. Please note that "Service Factory" is something "unsupported" as long as it resides in "Patterns&Practices" and does not count as a product.

I hope this overview gets you started on the quest for the WCF designer :)