Sample PROTO File Download

A .proto file defines a Protocol Buffers schema — the language-neutral contract for a binary serialization format. You declare message types with numbered fields, optionally enums and gRPC servicedefinitions, and a compiler generates typed code in Go, Java, Python, and more.

It underpins gRPC and a large share of internal service-to-service APIs because the wire format is compact and the numbered fields make forward and backward compatibility explicit.

Use the samples below to test a proto parser, check protoc code generation, or confirm editor support for proto3 syntax including nested types, maps, oneof, and streaming RPCs.