@sitespeed.io/plugin

Base class for sitespeed.io plugins. Extend it, implement processMessage, and sitespeed.io will instantiate and drive your plugin through the message queue.

See the plugin documentation for the full plugin lifecycle.

Install

npm install @sitespeed.io/plugin

Usage

sitespeed.io instantiates your plugin with the positional arguments new MyPlugin(options, context, queue). Your constructor must accept them in that order and forward them to super as a config object. The other lifecycle methods are called with their own positional arguments (shown below).

import { SitespeedioPlugin } from '@sitespeed.io/plugin';

export default class MyPlugin extends SitespeedioPlugin {
  // Optional: limit how many messages this plugin processes in parallel.
  // concurrency = 1;

  constructor(options, context, queue) {
    super({ name: 'myplugin', options, context, queue });
  }

  // Called once on startup. (context, options) are the same as the constructor's.
  async open(context, options) {
    // optional: setup on startup
  }

  // Called for every message on the queue. `queue` is the same as `this.queue`.
  async processMessage(message, queue) {
    if (message.type === 'url') {
      this.log.info('Got a URL: %s', message.url);
      await this.sendMessage('myplugin.data', { hello: 'world' });
    }
  }

  // Called once on shutdown.
  async close(options, errors) {
    // optional: cleanup on shutdown
  }
}

Lifecycle messages

While a run is in flight, sitespeed.io posts a few framework-level messages on the queue. Handle them in processMessage to hook into the run:

message.type	When
sitespeedio.setup	Plugins announce themselves / register filters
sitespeedio.summarize	All analysis is done — time to summarize
sitespeedio.prepareToRender	About to render output
sitespeedio.render	Write final output to storage

Other plugins emit their own message types (for example browsertime.pageSummary, browsertime.har, pagexray.run, …). See the plugin documentation for the full list.

API

• this.name / getName() — plugin name
• this.options / getOptions() — sitespeed.io start options
• this.context / getContext() — sitespeed.io context
• this.queue — the message queue
• this.log / getLog() — logger (call levels directly: this.log.info(...))
• getStorageManager() — storage manager for writing files
• getFilterRegistry() — filter registry for TimeSeries metrics
• sendMessage(type, data, extras) — post a message on the queue
• concurrency — optional class field; limits parallel processMessage calls
• open(context, options) / close(options, errors) — lifecycle hooks (override as needed)
• processMessage(message, queue) — must be implemented by your subclass

License

MIT