Friday, October 15, 2010

Debugging a WCF Data Service

Creating a WCF Data Service is really easy thanks to the built-in item template. Unfortunately when something goes wrong, a useless
“The server encountered an error processing the request” message is returned.
WCFDataServiceRequestError
There are 2 important settings that help you to return useful error messages.
1. Add a WCF serviceDebug behavior with the IncludeExceptionDetailInFaults property set to true.
This is especially useful when something failes during the WCF request pipeline and the WCF Data Service couldn’t be initialized.
   1:  <system.serviceModel>
   2:  <behaviors>
   3:  <serviceBehaviors>
   4:  <behavior>
   5:  <!-- To receive exception details in faults for debugging purposes, set the value below to true.  Set to false before deployment to avoid disclosing exception information -->
   6:  <serviceDebug includeExceptionDetailInFaults="true"/>
   7:  </behavior>
   8:  </serviceBehaviors>
   9:  </behaviors>
  10:  </system.serviceModel>

2. Set UseVerboseErrors to true in the ServiceConfiguration
   1:  public class WcfDataService2 : DataService<DataContext>
   2:      {
   3:  // This method is called only once to initialize service-wide policies.
   4:  public static void InitializeService(IDataServiceConfiguration config)
   5:          {
   6:              config.UseVerboseErrors = true;
   7:              config.SetEntitySetAccessRule("*", EntitySetRights.All);
   8:          }
   9:  }

2 comments:

Anonymous said...

Awesome. Out of all the blogs out there you are the only person to get the error data to display.

Anonymous said...

Ditto.
Thanks so much.