What are the cases that cause WCF proxy to be faulted?

Question

I want to know what are the cases in which WCF proxy (generated by vs2008 or svcutil) becomes faulted (fault state)? so I can recreate new instance and avoid use the faulted one.

currently I am handling TimeoutException,FaultException,CommunicationObjectAbortedException

            try
            {
                client.Method1(args);
            }
            catch (TimeoutException)
            {
                client.Abort();
                ReCreate();
            }
            catch (FaultException)
            {
                client.Abort();
                ReCreate();
            }
            catch (CommunicationObjectAbortedException)
            {
                client.Abort();
                ReCreate();
            }

I think I can avoid all these types and handle only the parent CommunicationException, is this sufficient? I need comments

Answer 1

WCF proxy object can become faulted because of any sort of exception except a faultException. So basically you best bet is just to check the proxy state and of it is faulted create a new one.

Another thing to keep in mind is that faulted is related to WCF sessions. If you don't need WCF sessions make sure to turn them off and you have prevented a whole series of possible issues.

Answer 2

Any uncaught exception on the server side that isn't handled and converted into a FaultException or FaultException<T> will likely fault your channel. In a per-call scenario or a one-way scenario, you often don't really care about the channel being faulted, but in a session-based scenario, you definitely will!

Your best bet is to really try and catch all exceptions on the server side and either just suppress them (log them on the server and don't do anything), or return them to the client in a FaultException way.

In order to do that, your service implementation should also implement the IErrorHandler interface which allows you to do just that - catch all exceptions and either logging+suppressing them, or converting them to SOAP faults.

Marc