Snaps OpenRPC Generator

Generate High end snaps in a snap.

A Generator tool for creating Metamask Snaps using open-rpc APIs.

It does this via an OpenRPC Generator Custom Component.

Features:

• Can generate:
  • Documentation
  • Snap Scaffold with strongly typed interfaces and service discovery via rpc.discover
  • Clients for accessing your snap (Not Implemented)

In a new project

Make a new folder for your Snap project

$ mkdir MySnap && cd MySnap

npm init

Install

$ npm install @xops.net/snaps-openrpc-generator @open-rpc/generator --save-dev

Usage

Create a generator config

open-rpc-generator-config.json

echo '{
  "openrpcDocument": "./openrpc.json",
  "outDir": "./generated",
  "components": [
      {
        "type": "custom",
        "name": "snap-openrpc-generator",
        "language": "typescript",
        "customComponent": "@xops.net/snaps-openrpc-generator/build/components/snap",
        "customType": "snap"
      },
      {
        "type": "custom",
        "name": "snap-docs-openrpc-generator",
        "language": "docs",
        "customComponent": "@xops.net/snaps-openrpc-generator/build/components/docs",
        "customType": "docs"
    }
  ]
}' > open-rpc-generator-config.json

Write an OpenRPC Document that describes your plugins interface, and includes any documentation, examples, etc you may want. You can start with one of the OpenRPC examples, write your own with the help of the OpenRPC Playground, or start from the hello world snap:

open-rpc.json

echo '{
  "openrpc": "1.2.4",
  "info": {
    "title": "MySnap",
    "version": "1.0.0"
  },
  "methods": [
    {
      "name": "hello",
      "description": "a method that returns world",
      "params": [],
      "result": {
        "name": "helloWorldResult",
        "schema": {
          "type": "string"
        }
      },
      "examples": [
        {
          "name": "helloWorldExample",
          "params": [],
          "result": {
            "name": "world",
            "value": "world"
          }
        }
      ]
    }
  ]
}' > openrpc.json

Run the OpenRPC Generator

$ npx open-rpc-generator generate -c open-rpc-generator-config.json

To run the generated snap:

cd generated/custom/typescript
npm install .
npm start

The resulting plugin is now at at http://localhost:8081 and which hosts the package.json and bundle.js needed for snaps.

To build the documentation:

cd into docs directory, install and start

cd generated/custom/docs
npm install .
npm start

you can now open http://localhost:8000 and view your generated, interactive documentation site.

and play around with the interactive api documentation at http://localhost:8000/api-documentation

Resources

• Getting Started Video (Demo) - EthDenver Hackathon 2020 - outdated on build steps but still really useful resource
• @open-rpc/generator package
• example open-rpc documents