Service Workers

This topic describes what service workers are and how to use them in platformOS.

Service workers

A service worker is a script that your browser runs in the background (separate from a web page) helping you to implement features that don't need a web page or user interaction. It's essentially a JavaScript file that runs separately from the main browser thread, intercepting network requests, caching or retrieving resources from the cache, and delivering push messages.

Service workers are like a new set of features on the web that allow you to turn an application into a Progressive Web App (also known as a PWA), send push notifications, and improve performance by caching.

Usage: Adding a service worker JavaScript file on root scope

For security reasons, service workers can intercept requests only from the scope they are in.

For example, assuming you have sw.js on example.com/assets/js/sw.js, your SW can control requests sent to paths starting with example.com/assets/js/ at most. That's why, most of the time, you want your SW file to be on the root domain, so you can control every request coming towards your application.

You can do that in platformOS by placing your SW files directly in the assets/ directory and using this pattern to name them:

• sw.js (and sw-X.js)
• serviceworker.js (and serviceworker-X.js)

Examples:

• assets/sw.js, assets/sw-2.js
• assets/serviceworker.js, assets/serviceworker-1.js

Read more on service workers

• Service Workers: an Introduction
• MDN web docs: Using Service Workers
• MDN web docs: Service Worker API