@protobuf-ts/plugin-framework

framework to create protoc plugins

Usage no npm install needed!

<script type="module">
  import protobufTsPluginFramework from 'https://cdn.skypack.dev/@protobuf-ts/plugin-framework';
</script>

README

@protobuf-ts/plugin-framework

A framework to create protoc plugins in typescript.

The google protocol buffer compiler (protoc) has a plugin system. With a protoc plugin, it is possible to generate code for .proto files in any language, not just the ones supported directly by protoc.

A protoc plugin receives a CodeGeneratorRequest (a protobuf message) via stdin and returns a CodeGeneratorResponse via stdout.

This framework aims to make it as easy as possible to write a protoc plugin in typescript. It has special support for generating typescript code, but can be used to generate code in other languages.

Features

  • provides a symbol table that can be used to track generated types in any language

  • has special support for generating typescript code using the typescript compiler API. For example, it has a simple API to import objects from a package, or from the symbol table.

  • provides a base class for plugins that supports parameters, error handling, supported features and easy setup.

  • builds a tree of descriptors so that it is trivial to lookup the parent of a nested message, for example.

  • builds a lookup object to find the descriptor for a given type name

  • provides a string format object that can print a message field like it was typed by the user.

  • provides a source code comment lookup that can be used to easily find comments for a given element in a .proto

  • provides convenience methods to check if a field was declared optional or as a oneof member

Getting started

  • Check the types and comments of descriptor.proto and plugin.proto to get familiar with the plugin system of protoc.
  • Take a look at descriptor-registry.ts to see the if it can help you work with the descriptor protos that the compiler sends you.
  • Take a look at plugin-base.ts for a base class that can help with some plumbing.
  • Take a look at the source code of protobuf-ts, which uses this framework.

Copyright

  • The files plugin.ts and descriptor.ts are Copyright 2008 Google Inc., licensed under BSD-3-Clause
  • All other files are licensed under Apache-2.0, see LICENSE.