Performance
Stop waiting on the network! You can improve your web app's performance by caching and serving your files, powered by a service worker.
Resilience
Even on an unreliable connection, your web app can still work using the right runtime caching strategies.
Enhancement
Looking to build a progressive web app? Workbox makes it easy to create an offline first experience.
Why Workbox?
Workbox is a library that bakes in a set of best practices and removes the boilerplate every developer writes when working with service workers.
- Precaching
- Runtime caching
- Strategies
- Request routing
- Background sync
- Helpful debugging
What's the API Like?
Below are a few examples of the Workbox API demonstrating some of the common approaches developers take in their service workers.
Cache Google Fonts
Wish you could rely on Google Fonts being available offline after the user has visited your site? Add a quick rule to serve them from the cache.
import {ExpirationPlugin} from 'workbox-expiration'; import {registerRoute} from 'workbox-routing'; import {StaleWhileRevalidate} from 'workbox-strategies'; // Cache Google Fonts with a stale-while-revalidate strategy, with // a maximum number of entries. registerRoute( ({url}) => url.origin === 'https://fonts.googleapis.com' || url.origin === 'https://fonts.gstatic.com', new StaleWhileRevalidate({ cacheName: 'google-fonts', plugins: [ new ExpirationPlugin({maxEntries: 20}), ], }), );
Cache JavaScript and CSS
Make your JS and CSS ⚡ fast by returning the assets from the cache, while making sure they are updated in the background for the next use.
import {registerRoute} from 'workbox-routing'; import {StaleWhileRevalidate} from 'workbox-strategies'; registerRoute( ({request}) => request.destination === 'script' || request.destination === 'style', new StaleWhileRevalidate() );
Cache Images
Images carry most of the weight for a web page. Use this rule to serve them quickly from the cache, while making sure you don’t cache them indefinitely, consuming your users' storage.
import {CacheableResponsePlugin} from 'workbox-cacheable-response'; import {CacheFirst} from 'workbox-strategies'; import {ExpirationPlugin} from 'workbox-expiration'; import {registerRoute} from 'workbox-routing'; registerRoute( ({request}) => request.destination === 'image', new CacheFirst({ cacheName: 'images', plugins: [ new CacheableResponsePlugin({ statuses: [0, 200], }), new ExpirationPlugin({ maxEntries: 60, maxAgeSeconds: 30 * 24 * 60 * 60, // 30 Days }), ], }), );
Precache your Files
Use Workbox to precache assets in your web app using our CLI, Node module or webpack plugin.
workbox wizard
const {generateSW} = require('workbox-build'); generateSW({ swDest: './build/sw.js', globDirectory: './app', globPatterns: '**/*.{js,css,html,png}', });
const {GenerateSW} = require('workbox-webpack-plugin'); module.exports = { // Other webpack config... plugins: [ // Other plugins... new GenerateSW(), ] };
Offline Google Analytics
Want offline analytics for your offline PWA? No problem.
import * as googleAnalytics from 'workbox-google-analytics'; googleAnalytics.initialize();
Workbox @ Chrome Dev Summit
Case Studies
Learn more about how developers are using Workbox in production:
Contributors
Workbox is built and maintained by a friendly bunch of contributors, without whom none of this would be possible.