Support Exception Propagation for .NET Core

[pardahlman]

Serialization in general, and of or Exception in particular is still an unresolved topic for .NET Core (https://github.com/dotnet/coreclr/issues/2715, https://github.com/dotnet/corefx/issues/6564). Until this issue is resolved, we should overlook how MessageHandlerException should be serialized and re-thrown for RPC.

[chrishaly]

it's very hardly to implements InnerException, StackTrace, Message etc. (de)serializable for json or xml.

I reveiwed the .NetCore Framework XmlSerializer it can serialize/deserialize InnerException, the method is use Reflection to access private fields. It's a very low level usage, private field is not contract and variable.

corefx\src\System.Private.DataContractSerialization\src\System\Runtime\Serialization\ExceptionDataContract.cs

            private static Dictionary<string, string> CreateExceptionFields()
            {
                var essentialExceptionFields = new Dictionary<string, string>(12);
                essentialExceptionFields.Add("_className", "ClassName");
                essentialExceptionFields.Add("_message", "Message");
                essentialExceptionFields.Add("_data", "Data");
                essentialExceptionFields.Add("_innerException", "InnerException");
                essentialExceptionFields.Add("_helpURL", "HelpURL");
                essentialExceptionFields.Add("_stackTraceString", "StackTraceString");
                essentialExceptionFields.Add("_remoteStackTraceString", "RemoteStackTraceString");
                essentialExceptionFields.Add("_remoteStackIndex", "RemoteStackIndex");
                essentialExceptionFields.Add("_exceptionMethodString", "ExceptionMethod");
                essentialExceptionFields.Add("_HResult", "HResult");
                essentialExceptionFields.Add("_source", "Source");
                essentialExceptionFields.Add("_watsonBuckets", "WatsonBuckets");
                return essentialExceptionFields;
            }

since Framework need to do like this why not support ISerializable?

[pardahlman]

Hi @chrishaly, thanks for the input! I did a somewhat similar discovery myself when looking into this. The ambition for 1.10.0 is to support netstandard1.5, and that is somewhat limiting to what can be done. Until there is a clean way to serialize exception for .NET Core, we'll have to do with the work-around in 3afb94d. Exception will be captured, metadata extracted and re-thrown in the Requester.

Let me know if you have any other suggestions for how to achieve this!