Protobuf UUID Helper Plugin

This project provides a collection of protoc plugins that generate helper methods to access UUID fields in Protobuf messages across multiple languages (currently Kotlin and Go). These helpers simplify UUID parsing by providing idiomatic accessors for fields that represent UUIDs as byte arrays or strings.

Features

• Language Support:

  • ✅ Go: Generates methods like func (m *OnlinePlayer) GetSessionUUID() uuid.UUID
  • ✅ Kotlin: Generates DSL extensions and functions like player.getSessionUUID()
  • 🧪 Extensible: Easily add support for more languages via a clean plugin structure

• Field Detection:

  • Automatically detects UUID fields based on the naming pattern *_uuid and protobuf type bytes
  • Also supports repeated bytes *_uuids fields

To see an example of what code is generated, see either the Go or Kotlin plugin's README.

Installation

Each language-specific plugin is located in its own folder under cmd/ with a README.md file.

Follow the instructions in the respective folder to build and use the plugin:

• Go Plugin
• Kotlin Plugin

All plugins can usually be built using the same command:

go build -o protoc-gen-uuidhelper-<lang> ./cmd/protoc-gen-uuidhelper-<lang>

It's recommended to add the plugin to your $PATH so you can invoke it directly.

To make this easier, there is a Taskfile.yaml, which requires Task to be installed. Then you can do

task install-<lang>

to install the plugin to your $PATH, or use the install task to install all available plugins.

Adding a new language

To add support for a new language, follow these steps:

1. Create a New Plugin Directory

   Create a new folder under cmd/ named protoc-gen-uuidhelper-<lang> (e.g., protoc-gen-uuidhelper-python).

2. Implement the Plugin

   Inside the new folder, create a main.go file that implements the following:

   • A backend struct the UUIDHelperBackend interface.
     • Please check out existing implementations for Go and Kotlin for reference.
     • The backend has to implement how the file is named and then return a new writer for this file.
   • A main function that then calls the Main method on the core package with the backend struct.
   • A writer struct that implements the UUIDHelperWriter interface.
     • Please check out existing implementations for Go and Kotlin for reference.
     • The writer has to implement what should be generated for the file header (e.g., package, imports, etc.) as well as what methods to generate for each UUID field.

   For generating the methods, there are various helper methods in the core package that can be used e.g., convert a fields name from Protobuf' snake_case to the target language's camelCase or PascalCase.

   Refer to the Go implementation in cmd/protoc-gen-uuidhelper-go/plugin.go for a simple example (the kotlin plugin is a lot more complex) of how to structure the plugin.

Tip

The writer will only be called for those fields that actually are considered "UUID-Fields" — therefore you don't have to filter the fields yourself, as that's already done by the core implementation.

3. Build the Plugin

   Build the plugin using the following command:

   go build -o protoc-gen-uuidhelper-<lang> ./cmd/protoc-gen-uuidhelper-<lang>

License

MIT License. See LICENSE for details.