gRPC.
also: GRPCA remote procedure call framework from Google: Protocol Buffers over HTTP/2, with generated client and server stubs.
the two-minute refresher
- Protobuf is a typed binary format: smaller and faster to (de)serialise than JSON.
- HTTP/2 gives multiplexing and streaming: unary, server-streaming, client-streaming and bidirectional calls.
- Code is generated from .proto files for many languages.
- Great between services; browsers and public APIs usually stay on REST/JSON.