Does anyone know of any problems with using WCF to expose a SOAP interface for non .NET clients?

Question

Does anyone know of any problems with using WCF to expose a SOAP interface for non .NET clients? For example incompatibilities with other SOAP libraries?

This is so that the SOAP interface can be exposed for third parties to integrate with our software.

Answer 1

Some of the problem areas I've encountered with WCF:

• It generates WSDL that is split across multiple URLs. That is, one part of the schema is at one URL, another is at a different URL, etc. The "main" WSDL URL (the one with just "?WSDL" after the service name) references the others via xsd:import elements. Many SOAP clients (eg pre-.NET Delphi) have enormous difficulty with this idiom. So you really have to "flatten" your WSDL in order to achieve interoperability in practice. One solution is given here.
• WCF doesn't generate XML namespaces the same way as, say, ASMX web services. WCF has a tendency to place any service or data contract into a namespace of its own choosing. Again, some SOAP clients have difficulty with this. You can increase you interoperability level by adding an explicit namespace to your ServiceContract and DataContract attributes.
• Many SOAP clients won't handle faults as nicely as WCF clients. For example, the proxy generation code won't create client-side objects for the faults declared in the WSDL. The faults will still be transmitted to the client, of course, but the client then has to do more work to figure out what kind of fault it was.