sw-register

Service Worker registration utility

Made with ❤ at @outlandish

Register or retrieve a Service Worker that controls the page with ease...

• Register a Service Worker with one call to register(<options>)
• Get an existing Service Worker with one call to register()
• Always favours returning the active Service Worker over registering a new one, which means you can put a call to register(<options>) with options in your init procedure and it will not try to re-register the worker. Saving you having to inspect navigator.serviceWorker.ready manually, etc.

Import

// ES6
import register from 'sw-register'

// CommonJS
var register = require('sw-register')

// RequireJS
define(['sw-register'], function (register) {/*...*/})

<!-- Script, available as `window.swRegister` -->
<script src="/node_modules/sw-register/index.js"></script>

Register

const register = require('sw-register')

// Get existing worker
register().then((worker) => {
  const channel = new MessageChannel()
  worker.postMessage("Hey!", [channel.port2])
})

// Register a worker from the client
// Worker scope depends on worker location/headers
// Read the Service Worker docs for more details
const registration = {
  url: '/sw.js',
  scope: '/'
}

// Subsequent calls with a registration object
// will not attempt re-registration but return
// the existing registered worker instead
register(registration).then((worker) => {
  const channel = new MessageChannel()
  worker.postMessage("Hey!", [channel.ports2])
})

// Catch registration error
register().catch((err) => {
  console.log(err.message)
})

Usage

register([options]) : Promise

Register or retrieve a Service Worker.

• [register] {Object} Options object

Returns the Service Worker controller.

Available options (any not listed can also be passed in):

• url (required) the URL of the service worker
• scope (optional) the scope of the service worker
• forceUpdate (optional) call update() on the registration?

Example:

register().then((worker) => {
  // do something with the worker
}).catch((err) => {
  // you get here if:
  // - service workers unsupported
  // - no existing worker and no options given to register one
})

Contributing

All pull requests and issues welcome!

If you're not sure how, check out Kent C. Dodds' great video tutorials on egghead.io!

Author & License

sw-register was created by Sam Gluck and is released under the MIT license.