workbox Files

The latest beta release of Workbox v4 includes the following developer-visible changes, in addition to all the changes from the previous pre-releases.

🎉 What's New?

workbox-window

• The Workbox constructor function signature has changed to accept an optional scriptVersion option. To support this new option (and other future options) the constructor now accepts a single object argument [#1861].

  :::js // Old way new Workbox(scriptURL, registerOptions);

  // New way new Workbox({ scriptUrl, scriptVersion, registerOptions, });

• The properties .active and .controlling have been added to the Workbox class. These are promises which will resolve as soon as Workbox has a reference to a service working in the corresponding state (active or controlling) with a matching scriptURL (and optionally scriptVersion, if used). These are similar to the navigator.serviceWorker.ready promise, but when using scriptVersion you can be sure they won't resolve until the correct version of the script is active/controlling [#1861].

• Workbox event listeners are now always called with an Event-like object (i.e. they have a .type, .target properties), to more closely match how native event listeners work. In the future when all browsers support contructable EventTarget, these will be native Event objects [#1861].

  :::js // Old way myWorkbox.addEventListener('activated', (sw) => { // Do something with sw. });

  // New way myWorkbox.addEventListener('activated', (event) => { // The activated service worker is at event.sw. // And the underlying event that triggered this is at event.originalEvent. });

• The controlling event is now dispatched prior to the activated event, which correctly matches the ordering of when the controllerchange and statechange events fire in the service worker lifecycle. [#1861]

workbox-routing

• The workbox.routing.Router#addCacheListener() method has updated the format off messages it can receive from the window to cache. Previously it would accept an array of URL strings, now it can also accept an array of URL strings or arrays in the form of [url, requestInit]. This is useful if you need to override the default request mode [#1851]

Build tools

• Support for a new boolean configuration option, cleanupOutdatedCaches, has been added to the GenerateSW mode of all of the build tools. It defaults to false. When set to true, a call to workbox.precaching.cleanupOutdatedCaches() will automatically be added to your generated service worker, which will in turn delete any out-of-date precaches no longer used by Workbox. Workbox v4 introduced a breaking change to the precache format, so developers upgrading from Workbox v3 or earlier might find this useful. [#1863]

🐛 What's Fixed?

workbox-webpack-plugin

• In addition to swSrc being a file on file system, it can now be a webpack generated asset as well. This allows users to compile their service worker with webpack and then give it as a source to inject-manifest plugin. [#1763]

workbox-core

• Don't set fetchOptions when request.mode is 'navigate', to work around an issue that could lead to failed navigations. [#1862]