Communication Protocols — gRPC vs REST vs GraphQL in Go Microservices
Prerequisite: This is Part 12 of the System Design Masterclass. Previous parts built the reliability patterns — this part covers comparing communication protocols and data formats for microservice communication. Answer-first: gRPC is optimized for internal microservices using binary Protobuf serialization over multiplexed HTTP/2 or HTTP/3 streams. REST uses standard JSON over HTTP/1.1 or HTTP/2, serving as the default for public APIs. GraphQL operates as an aggregator at the API gateway or Backend-for-Frontend (BFF) layer, allowing clients to query specific properties, but requires complexity limits and DataLoader batching to prevent server degradation. ...