Returning an Object that contains a List member in WCF service

Question

I have the follow classes in my Shared.DataContracts DLL

[DataContract]
public class TestClass
{
   [DataMember]
   public int Group { get; set; }

   [DataMember]
   public List<TestClassTwo> Member { get; set; }
}

[DataContract]
public class TestClassTwo
{
   [DataMember]
   public long MessageId { get; set; }

   [DataMember]
   public RequestOpType ResultType { get; set; }
}

[DataContract(Name = "RequestOperationType")]
public enum RequestOpType
{
   [EnumMember]
   Add,
   [EnumMember]
   Delete,
   [EnumMember]
   Update,
   [EnumMember]
   Retrieve,
   [EnumMember]
   Search
}

My service contract is as follows:

[ServiceContract]
public interface IConnectorService
{
    [OperationContract]
    void PustRequestToWorkBuffer(TestClass test); 
}

[ServiceBehavior(InstanceContextMode = InstanceContextMode.Single)]
public class ConnectorService : IConnectorService
{
    public void PustRequestToWorkBuffer(TestClass test)
    {
        return;
    }
}

When I try to add the following as a Service Reference to one of my projects I always get an error being thrown by WSDL. The project has a reference to Shared.DataContracts DLL. I therefore add the Service Reference by leaving the 'Re-use typres in referenced assemblies' check box ticked.

I get this error:

Error 73 Custom tool error: Failed to generate code for the service reference 'ServiceReference1'. Please check other error and warning messages for details. S:\\src\\test\\source\\test\\Connector\\Service References\\ServiceReference1\\Reference.svcmap 1 1 MetaConnector

The warning is:

Warning 68 Custom tool warning: Cannot import wsdl:portType Detail: An exception was thrown while running a WSDL import extension: System.ServiceModel.Description.DataContractSerializerMessageContractImporter Error: Referenced type 'Poc.Shared.DataContract.TestClass, Poc.Shared, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null' with data contract name 'TestClass' in namespace ' http://schemas.datacontract.org/2004/07/Poc.Shared.DataContract ' cannot be used since it does not match imported DataContract. Need to exclude this type from referenced types. XPath to Error Source: //wsdl:definitions[@targetNamespace=' http://tempuri.org/ ']/wsdl:portType[@name='IConnectorService'] S:\\src\\source\\MetaConnector\\Service References\\ServiceReference1\\Reference.svcmap 1 1 MetaConnector

If I remove List<TestClassTwo> from the TestClass and replace it with just a TestClassTwo member it works fine. Looks like having a List is the cause of my problem.

I need to re-use the types in the shared assembly so un-checking this option is not applicable (that would remove the error though).

EDIT: I think the visual studio 'Add Service Reference' functionality is a bit flaky based on reading around. Since I controlled both the client and server I re-factored my code to share the contract and use a ChannelFactory instead. Although I did use the same contracts in a separate solution and everything seemed okay. I have a feeling the client and server solutions had some issues and they were looking at different versions of the Shared.DataContracts.DLL.

Answer 1

Try adding new DataContract like :

[DataContract]
public class ListTestClassTwo
{
   [DataMember]
   public List<TestClassTwo> Member { get; set; }

   public ListTestClassTwo()
   {
        Member = new List<TestClassTwo>();
   }
}

Then define it inside TestClass like:

[DataContract]
public class TestClass
{
   [DataMember]
   public int Group { get; set; }

   [DataMember]
   public ListTestClassTwo ListOfMembers { get; set; }
}

I think this should work.

OR Alternatively you can try KnownType for TestClassTwo over TestClass like:

[DataContract]
[KnownType(typeof(TestClassTwo))]
public class TestClass
{
   [DataMember]
   public int Group { get; set; }

   [DataMember]
   public List<TestClassTwo> Member { get; set; }
}

Update:

If you are reusing assembly make sure same version of assembly is referenced everywhere it is used. Each time I faced error having Cannot import wsdl:portType Detail , it's always something to do with mismatch of assembly versions which is reused.

Last time I faced similar issue it was that I added some attribute into some DataContract & it was reused but from where it was referenced had the old version not having new added attributes, that was the cause of issue.