Enable gPRC proxy renderer while recording gRPC traffic

[elune1108]

References

• TODO

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[tomakehurst]

I'm wondering whether this architectural approach is the best one. The requirement to downcast the original request to a GrpcRequest feels like a leaked abstraction, which may have unintended consequences when working with other extensions.

Similarly, the addition of grpc to the mime types the recorder in the core looks for seems like a coupling that shouldn't exist.

Did you consider the option of keeping the proxy response renderer as-is and building a custom HttpClientFactory instead? i.e. one that has the default behaviour when it's a non-gRPC request, but builds and executes a gRPC request when it is.
This would keep WireMock's abstractions more intact - the internal view of the request/response would be plain JSON, and also we could probably avoid having to make changes to the core.