Question

I was able to get this working for different projects and believe im following the same path/pattern but something is missing.
I keep getting a poison message when I send a message of a known type on the MSMQ.

I have a class called ConcreteClass which has several properties, decorated with DataMember attributes. I have a “Base” class which the ConcreteClass derives from.
I can send the message to the MSMQ fine but when reading from the MSMQ using WCF, the service always faults and looking at the logs, it is a poison message.

the WCF service is using the base class as the signature (which worked fine in a different project) and has serviceknowntype attributes decorated for the concrete classes the service should expect.

[ServiceKnownType(typeof(ConcreteClass))]
public sealed class WCFServiceMSMQReader : IWCFServiceMSMQReader { 
   [OperationBehavior(TransactionScopeRequired = true, TransactionAutoComplete = true)]
   public void ProcessIncomingMessage(MsmqMessage<BaseClass> msg) { .... do stuff .... }
}

interface:

[ServiceContract]
public interface IWCFServiceMSMQReader {
   [OperationContract(IsOneWay = true, Action = "*")]
   void ProcessIncomingMessage(MsmqMessage<BaseClass> msg);
}

BaseClass:

[DataContract]
[KnownType(typeof(ConcreteClass))]
public class BaseClass
{
   ... some properties here...
}

ConcreteClass:

[DataContract]
public class ConcreteClass : BaseClass {

public ConcreteClass() : base() { ... stuff ... }
public ConcreteClass(params here) : base() { .... }

}

any ideas where I am going wrong?

Answer 1

The service known types should be declared in the interface