grpcmd vs protoc-gen-doc

grpcmd is a free command-line tool for working with gRPC services on Linux, macOS, and Windows. It can use reflection to find available services and methods, describe a method’s request and response messages, and make calls. Requests and responses can stream, with headers, data, and trailers included in output. Users who do not want to rely on reflection can instead provide.proto files and import search paths. The tool can also start a gRPC server implementing grpcmd.GrpcmdService with reflection, and its documentation covers shell completion for Bash, Zsh, fish, and PowerShell. A related tool, grpcmd-script, lets users define endpoint tests in JavaScript and assert response headers, data messages, and trailers; it is distributed as a binary and does not require Node.js. The separate grpcmd-gui desktop app supports reflection-based method lookup, request headers, response headers and trailers, JSON request templates, streaming, and themes. GUI downloads are available for macOS, Windows, and Linux, including amd64 and arm64 builds. grpcmd is listed at free; grpcmd-script is listed at $9 a year with early-bird pricing.

protoc-gen-doc is a documentation generator plugin for the Google Protocol Buffers compiler. It turns comments in .proto files into HTML, JSON, DocBook, or Markdown documentation, covering files, messages, fields, services and methods, enums and values, and extensions. It supports proto2 and proto3, including both in the same context. You can exclude files with path patterns and omit comments marked with the @exclude prefix. The plugin runs through protoc with the --doc_out and --doc_opt options; its source_relative flag places generated output in the same relative directory as the input. For customization, users can supply a Go template or use a stylesheet.css file to change HTML appearance. Installation options include Go, prebuilt releases, a Docker image, and a Maven Central package. It runs on Linux, macOS, and Windows and is self-hosted. The project is free under the MIT License, which allows use, modification, distribution, sublicensing, and sale under its terms. The license provides the software as is, without warranty.