Silverlight & WCF Debugging and using Fiddler!

12. April 2010
Comments (0)

 

Fiddler2 Best program out there I think for debugging WCF errors in silverlight when you get “NotFound” error messages.

 

Example. I had a Silverlight application where I had to enable it work over https and change the host headers. As many of you may know, WCF on .NET 3.5 you can not bind to website with multiple headers. You have to hardcode the WCF Address in the web.config. (I’ve read that .Net 4.0 will allow this but still not for ssl).

All my setting from what I can tell in my web.config and my clientConfig were correct, and the app worked fine in http mode only, however I would get the most generic message ever.

image

This is my custom error window I use to have users send the errors to the server.  As you can see the error is “The remote server returned an error: NotFound.”  this is basically the equivalent of the old server error message “An Unexpected Error Occurred”.  Basically who knows. Something’s wrong.  The WCF service is not responding. Could be your firewall, your IIS, your service is erroring out or 100 other things. 

Download and install Fiddler2 and let the magic begin.  I did try WebDevHelper which is like FireBug for FireFox but it works in IE.  It’s pretty good, but like FireBug, doesn’t give you that WCF error.

Loading up Fiddler, I can inspect the traffic and actually see the .Net error. It even highlights it in red for me.  (Had to block out the app names).

image

From this I was able to expand the information like below to see the real error message.

image

“Cannot be process at the receiver, due to an AddressFilter mismatch at the EndpointDispatcher.  Check that the sender and receiver’s EndPointAddresses agree”

After I realized what the problem was I was able to fix my service by adding the attribute AddressFilterMode:=AddressFilterMode.Any to my WCF class.

<ServiceContract(Namespace:="")> _
<ServiceBehavior(IncludeExceptionDetailInFaults:=True, AddressFilterMode:=AddressFilterMode.Any)> _
<AspNetCompatibilityRequirements(RequirementsMode:=AspNetCompatibilityRequirementsMode.Allowed)> _
Public Class xxxxxxxxxxxService

 

Problem Solved.

 

WCF logging:

You can also log all your WCF Traffic to a Log file on your server.

  <system.diagnostics>
      <sharedListeners>
          <add name="WcfListener"
                  type="System.Diagnostics.XmlWriterTraceListener"
                    initializeData="C:\logs\wcfLog.svclog"/>
      </sharedListeners>
      <sources>
          <!-- switchValue attribute has no impact on MessageLogging -->
          <source name="System.ServiceModel.MessageLogging">
              <listeners>
                  <add name="WcfListener" />
              </listeners>
          </source>
          <source name="System.ServiceModel"
                        switchValue="Warning, ActivityTracing"
                        propagateActivity="true" >
              <listeners>
                  <add name="WcfListener" />
              </listeners>
          </source>
      </sources>
  </system.diagnostics>

 

<system.serviceModel>
    <diagnostics>
        <messageLogging
             logEntireMessage="true"
             logMalformedMessages="false"
             logMessagesAtServiceLevel="true"
             logMessagesAtTransportLevel="false"
             maxMessagesToLog="3000"
             maxSizeOfMessageToLog="2000"/>
    </diagnostics>
</system.serviceModel>

 

Other useful posts..

Silverlight and WCF – WCF Logs and Debugging

Service Trace Viewer Tool (SvcTraceViewer.exe)

Silverlight & WCF - HTTPS

WCF, SilverLight, Troubleshooting , , , ,

Sending Generic.List collection back to WCF ObservableCollection

16. December 2009
Comments (2)

Found a good article and helped with a problem I was having, trying to send a list of collection back to a WCF service that was set to accept Observable Collections. 

Source: http://smehrozalam.wordpress.com/2009/01/18/ienumerabletoobservablecollection/

In WPF/Silverlight, binding UI objects such as DataGrid or ListBox to collections is typically done using an ObservableCollectioninstead of the generic List object. This way, our UI is automatically synchronized since the observable collection provides event notification to WPF data binding engine whenever items are added, removed, or when the whole list is refreshed. The LINQ extension methods that return a collection actually return IEnumerable<T>. The .NET framework for Silverlight provides built-in extension methods to convert IEnumerable<T> to List<T> and Array<T> but there’s no method available to convert the collection to ObservableCollection<T>(WPF developers can simply use this constructor overload) . So here’s one you may find useful:

  1. Public Static Class CollectionExtensions
  2. {
  3.     public static ObservableCollection<T> ToObservableCollection<T>(this IEnumerable<T> enumerableList)
  4.     {
  5.         if (enumerableList != null)
  6.         {
  7.             //create an emtpy observable collection object
  8.             var observableCollection = new ObservableCollection<T>();
  9.  
  10.             //loop through all the records and add to observable collection object
  11.             foreach (var item in enumerableList)
  12.                 observableCollection.Add(item);
  13.  
  14.             //return the populated observable collection
  15.             return observableCollection;
  16.         }
  17.         return null;
  18.     }
  19. }

Extension methods are very powerful and I am planning to post an example demonstrating their potential.

I’ve converted the above example to VB.Net version for you to copy.

Public Shared Function ToObservableCollection(Of T)(ByVal enumerableList As IEnumerable(Of T)) As ObservableCollection(Of T)
    If enumerableList IsNot Nothing Then
        'create an emtpy observable collection object
        Dim observableCollection As New ObservableCollection(Of T)()

        'loop through all the records and add to observable collection object
        For Each item As T In enumerableList
            observableCollection.Add(item)
        Next

        'return the populated observable collection
        Return observableCollection
    End If
    Return Nothing
End Function

Now you can call your List and send it back as a ObservableCollection

.Net Framework, Code Snippets, Programming, VB.NET, WCF, SilverLight , , , ,

HTTP Error 404.17 Not Found – Using WCF .SVC Service

30. November 2009
Comments (0)

So you’re getting IIS error’s when trying to run a .svc file that’s coded to use WCF or Windows Communication Foundation.

HTTP Error 404.17 - Not Found

The requested content appears to be script and will not be served by the static file handler.

or maybe..

HTTP Error 404.3 - Not Found

The page you are requesting cannot be served because of the extension configuration. If the page is a script, add a handler. If the file should be downloaded, add a MIME map.

Took me awhile to realize I need to setup/configure IIS and WCF properly.  Here are the steps from MS, I went through and realized I had missed one component (IIS6 Scripting tools, who would have thought), which I probably didn’t need, but the big ones that I didn’t have WCF Http Activation installed.  After that, I registered WCF..

"%WINDIR%\Microsoft.Net\Framework\v3.5\WFServicesReg.exe" /c

and then I was golden, but there might be other things you are lacking or missing. So go through all the steps.

One-Time Set Up Procedure for the Windows Communication Foundation Samples

ASP.NET, IIS And Hosting, WCF , ,