@remixproject/engine

Engine

The engine manages

• Plugin registration
• Plugin activation
• Plugin communication

Tutorial

1. Getting Started
2. Plugin Communication
3. Host a Plugin with UI
4. External Plugins
5. Plugin Service

APIs

• Engine
• Plugin Manager

Getting started

npm install @remixproject/engine

The engine works a with two classes :

• PluginManager: manage activation/deactivation
• Engine: manage registration & communication

import { PluginManager, Engine, Plugin } from '@remixproject/engine'

const manager = new PluginManager()
const engine = new Engine(manager)
const plugin = new Plugin({ name: 'plugin-name' })

// Wait for the manager to be loaded
await engine.onload()

// Register plugins
engine.register(plugin)

// Activate plugins
manager.activatePlugin('plugin-name')

Registration

The registration make the plugin available for activation in the engine.

To register a plugin you need:

• Profile: The ID card of your plugin.
• Plugin: A class that expose the logic of the plugin.

const profile = {
  name: 'console',
  methods: ['print']
}

class Console extends Plugin {
  constructor() {
    super(profile)
  }
  print(msg: string) {
    console.log(msg)
  }
}
const consolePlugin = new Console()

// Register plugins
engine.register(consolePlugin)

In the future this part will be manage by a Marketplace plugin.

Activation

The activation pocess is managed by the PluginManager.

Actvating a plugin makes it visible by other plugins. Now they can communicate.

manager.activatePlugin('console')

The PluginManager is a plugin itself.

Communication

Plugin exposes a simple interface to communicate with each others :

• call: Call a method exposed by another plugin (This returns always a Promise).
• on: Listen on event emitted by another plugin.
• emit: Emit an event broadcasted to all listeners.

This code will call the method print from the plugin console with the parameter 'My message'.

plugin.call('console', 'print', 'My message')

Full code example

import { PluginManager, Engine, Plugin } from '@remixproject/engine'
const profile = {
  name: 'console',
  methods: ['print']
}

class Console extends Plugin {
  constructor() {
    super(profile)
  }
  print(msg: string) {
    console.log(msg)
  }
}

const manager = new PluginManager()
const engine = new Engine(manager)
const emptyPlugin = new Plugin({ name: 'empty' })
const consolePlugin = new Console()

// Wait for the manager to be loaded
await engine.onload()

// Register plugins
engine.register([plugin, consolePlugin])

// Activate plugins
manager.activatePlugin(['empty', 'console'])

// Plugin communication
emptyPlugin.call('console', 'print', 'My message')