GRPC-PROTOBUF
The standard modern RPC duo — Protobuf for types, gRPC for transport.
Definition
A .proto file defines both (1) messages (data structs) and (2) services (RPC methods with input/output signatures). The protoc compiler generates client and server in 11+ languages. 5-10x faster than REST+JSON. Native bidirectional streaming. Adopted by Google, Netflix, Spotify, Square, Lyft.
Origin
gRPC released by Google in 2015, based on stubby (internal Google RPC since 2001).
Example in context
service EdiParser { rpc ParseEdifact (ParseRequest) returns (stream ParsedSegment); }