[ahuang]

gRPC isn't a requirement for response streaming (as is quoted as one of the main reasons for doing the migration). That can all be achieved with http/json using chunked encoding. In fact, that's what the gRPC-gateway (http/json gateway to a gRPC service) does https://github.com/grpc-ecosystem/grpc-gateway.

gRPC adds bi-directional streaming which is not possible in http, but the use cases for that are more specialized.

[anderspitman]

Sure, the actual transfer will be streamed, but most JSON clients wait for the entire response before firing your callback. As far as I know there isn't even a commonly used spec for partially reading a JSON document.