I'm pretty much repeating what I posted here on the MSDN forum, but my work around seems to be doing fine so I thought it's worth noting down in case someone else comes across this problem.
If you're using the XmlSerializer rather than the default DataContractSerializer, beware that once you are out of the context of the service implementation (i.e. in a behaviour), WCF will use the DataContractSerializer. Why is this a problem?
Well, if you have implemented IErrorHandler, and are recreating the fault message that is returned to the client (e.g. using the CreateMessageFault method from the FaultException instance), the message has been serialized again. The trouble is, there is no way as far as I am aware of specifying which serializer to use (hence the reason for my post on MSDN) and WCF resorts back to its default of the DataContractSerializer.
I'm using a fault contract when creating the FaultException - i.e. FaultException and my ErrorInfo type in decorated with the appropriate Xml attribute indicating its Xml type and namespace. Eg:
[XmlType("ErrorInfo", Namespace="http://FaultContract")]
public class ErrorInfo
When this is returned back to the client, a different namespace arrives for the ErrorInfo type (rather than FaultContract), which means the client can't deserialize it. The xml namespace instead is http://schemas.datacontract.org/2004/07/ etc which is not what the client is expecting.
The reason this is happening is that the DataContractSerializer is looking for the DataContract attribute to determine what to use for the xml namespace. Since the ErrorInfo type isn't decorated with this attribute, which makes sense - I'm not using the DataContractSerializer, a default namespace is used instead.
To fix this, I have decorated the ErrorInfo type with both the XmlType attribute, and DataContract attribute:
[DataContract(Name="ErrorInfo", Namespace="http://FaultContract")]
[XmlType("ErrorInfo", Namespace="http://FaultContract")]
public class ErrorInfo
This now handle both scenarios, the Fault message created within the context of the service (where you can specify the serializer to use), and the Fault message created within a behaviour.
If you're using the XmlSerializer rather than the default DataContractSerializer, beware that once you are out of the context of the service implementation (i.e. in a behaviour), WCF will use the DataContractSerializer. Why is this a problem?
Well, if you have implemented IErrorHandler, and are recreating the fault message that is returned to the client (e.g. using the CreateMessageFault method from the FaultException instance), the message has been serialized again. The trouble is, there is no way as far as I am aware of specifying which serializer to use (hence the reason for my post on MSDN) and WCF resorts back to its default of the DataContractSerializer.
I'm using a fault contract when creating the FaultException - i.e. FaultException and my ErrorInfo type in decorated with the appropriate Xml attribute indicating its Xml type and namespace. Eg:
[XmlType("ErrorInfo", Namespace="http://FaultContract")]
public class ErrorInfo
When this is returned back to the client, a different namespace arrives for the ErrorInfo type (rather than FaultContract), which means the client can't deserialize it. The xml namespace instead is http://schemas.datacontract.org/2004/07/ etc which is not what the client is expecting.
The reason this is happening is that the DataContractSerializer is looking for the DataContract attribute to determine what to use for the xml namespace. Since the ErrorInfo type isn't decorated with this attribute, which makes sense - I'm not using the DataContractSerializer, a default namespace is used instead.
To fix this, I have decorated the ErrorInfo type with both the XmlType attribute, and DataContract attribute:
[DataContract(Name="ErrorInfo", Namespace="http://FaultContract")]
[XmlType("ErrorInfo", Namespace="http://FaultContract")]
public class ErrorInfo
This now handle both scenarios, the Fault message created within the context of the service (where you can specify the serializer to use), and the Fault message created within a behaviour.
This took me a while to determine why this was occuring, but eventually I was able to isolate where the problem was (the behaviour). When I turned the IErrorHandler behaviour off, the client was able to deserialize the ErrorInfo type correctly (as the correct namespace was used).
IErrorHandlerProvideFault serialization is a crucial aspect of error handling in software development. It involves converting error information into a format suitable for transmission or storage. Best Mouse This process ensures that error details can be communicated effectively.
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