Support returning multiple streaming responses for a unary gRPC request

[subnova]

Support returning multiple streaming responses for a unary gRPC request.

Implementation

The JSON response is parsed into a JSON tree using Jackson's MappingIterator. Each JSON document is then mapped to a gRPC response as before and emitted using the gRPC stub response observer.

References

#55

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[tomakehurst]

Thanks for contributing this. I'm going to hold off merging it though, as we plan to expand WireMock's core model for streaming/multi chunk responses and then utilise this for gRPC streaming.

[subnova]

Look forward to seeing a more complete solution - but this would be a useful stop-gap for those of us who desperately need this feature.

[tomakehurst]

OK, that's fair enough, but let's find a way to enable this explicitly rather than it being the default behaviour when there's a streamed response defined.

I suggest adding a response definition transformer that's enabled per-stub, that sets a response header indicating this behaviour be enabled. So e.g. the transformer would add grpc-convert-response-body-array-to-stream:true to the headers, then there'd be an if block around the code you've already written that checks this is true.

[tomakehurst]

Suggest adding an overload taking a vararg so that it's not necessary to put List.of(...) when calling.

[tomakehurst]

Is serialising the whole list not possible?

Seems a bit messy to have to do string concat like this.