I have an existing java grpc server file that is generated from a .proto file. I need to add HTTP REST API endpoints for each of the rpc calls in my .proto file. Probably using google.api.http.
The .proto file looks something like:
rpc GetShelves(GetShelvesRequest) returns (stream Shelf);
In the grpc service, this turns into:
public StreamObserver<GetShelvesRequest> GetShelves( StreamObserver<GetShelvesResponse> responseObserver) { /* do something */ }
However, the StreamObserver is a class provided by gRPC and it's not applicable for HTTP. Ideally, I'd use the StreamingResponseBody interface in Spring MVC to write directly to the response body as bytes are available in my REST endpoint. However I want to reuse the same .proto file to enforce consistency across my two API endpoints.
From the google.api.http documentation for transcoding, I should add an annotation like:
rpc GetShelves(GetShelvesRequest) returns (stream Shelf) { option (google.api.http) = { get: "/v1/shelves/" }; }
To add an http end point. But the stream keyword will generate a SteamObserver.
How do I use the same .proto file, but have the end result be a StreamObserver for grpc but a StreamingResponseBody for http?
n/a, described above.
