Return null in service but throw a exception No message returned from method.

[ElderJames]

I think the expected behavior should be returning null in client side

[mgravell]

That's an interesting one, because protobuf has no concept of null, and no way to encode null. We could abuse headers, but I suspect that adds confusion because that would only work if both client and server knew about it, i.e. it would only work protobuf-net.Grpc to protobuf-net.Grpc

Frankly, I wonder if the best option is to leave it as-is. Thoughts?

[GoNextGroup]

Maybe, It's a solution to pass an "object" as a "null-value"?

[mgravell]

An outer message with an optional inner message works well. That I can encode.

[mgravell]

This is fundamentally not doable in the general case because protobuf has no null; I think the answer here is: "don't do that"