Response body as a single field

[BrianHicks]

Part of the API I'm covering needs to be able to return just bytes. Right now I have something similar to the following:

message Content {
  string content = 1;
}

for RPC, that's just fine; the client can unwrap it. However, over HTTP I don't want a wrapping JSON, I only want that content field. Is there a way to specify this in the gateway configuration?

[yugui]

You can write a custom marshaler to do that.
Also, what grpc-gateway generates is an ordinary HTTP handler in Golang. So you can do whatever you want by wrapping the handler.

[BrianHicks]

Is there documentation or an example of where to put the custom marshaller? It doesn't jump out at me where it should go.

[skylarbpayne]

Hey @BrianHicks , I see your question was never answered. You can use the WithMarshalerOption in your entry point:

grpc-gateway/runtime/marshaler_registry.go

Line 85 in acebe0f

func WithMarshalerOption(mime string, marshaler Marshaler) ServeMuxOption {

Hope that helps :).