Question

I am working on an asp .net net project which calls a workflow service. I want to call the service without adding it as a service to the solution. I am using the following code

XNamespace ns = "http://schemas.microsoft.com/2003/10/Serialization/";

var factory = new ChannelFactory<IGenericService>(new BasicHttpBinding(), new EndpointAddress("http://localhost:2757/BPMNSimple.xamlx"));

var proxy = factory.CreateChannel();

var request = Message.CreateMessage(MessageVersion.Soap11, "http://tempuri.org/IService/TestSimple", new XElement(ns + "string", "45"));

var response = proxy.GetData(request); 

var xml = (XElement)XElement.ReadFrom(response.GetReaderAtBodyContents());
var message = xml.Value;
lblMessage.Text = message.ToString();

In the xamlx file the receive activity takes one argument which is a string and the sendreplytoreceive activity gives 2 parameters as an output. I get the following error when i run this code:

System.ServiceModel.CommunicationException: The server did not provide a meaningful reply;   
this might be caused by a contract mismatch, a premature session shutdown or an internal server error. Server stack trace: 
at System.ServiceModel.Channels.ServiceChannel.Call(String action, Boolean oneway, ProxyOperationRuntime operation, Object[] ins, Object[] outs, TimeSpan timeout) 
at System.ServiceModel.Channels.ServiceChannelProxy.InvokeService(IMethodCallMessage methodCall, ProxyOperationRuntime operation) 
at System.ServiceModel.Channels.ServiceChannelProxy.Invoke(IMessage message) Exception rethrown at [0]: 
at System.Runtime.Remoting.Proxies.RealProxy.HandleReturnMessage(IMessage reqMsg, IMessage retMsg) 
at System.Runtime.Remoting.Proxies.RealProxy.PrivateInvoke(MessageData& msgData, Int32 type) 
at _Default.IGenericService.GetData(Message request) 
at _Default.Page_Load(Object sender, EventArgs e) in c:\Users\marios\Documents\Visual Studio 2010\WebSites\WebSite2\Default.aspx.cs:line 63 

Answer 1

In the first instance, turn IncludeExceptionDetailsInFaults on on the service side. You will be able to get more information from http://msdn.microsoft.com/en-us/library/system.servicemodel.description.servicedebugbehavior.includeexceptiondetailinfaults.aspx.

You’ll need to add something like the following to your services web.config:

 <serviceDebug includeExceptionDetailInFaults="true" />

Eidt:
So the next thing to try is using the built in error handling to see if you can see what is happeneing serveside. Have a read of this MSDN article. You need to add someting like:

<configuration>
 <system.diagnostics>
  <sources>
        <source name="System.ServiceModel" 
                switchValue="Information, ActivityTracing"
                propagateActivity="true">
        <listeners>
           <add name="traceListener" 
               type="System.Diagnostics.XmlWriterTraceListener" 
               initializeData= "c:\log\Traces.svclog" />
        </listeners>
     </source>
  </sources>
</system.diagnostics>

This will create a WCF log file where you can (hopefully) see an error relating to your request.