app_offline_sw.js

const CACHE_VERSION = 'motor-control-client-v1';
const URLS_TO_CACHE = [
  './',
  './css/main.css',
  './img/motor_icon_192.png',
  './img/motor_icon_512.png',
  './img/settings_icon.svg',
  './js/api_logic.js',
  './js/jquery-3.7.1.min.js',
  './js/keypad_logic.js',
  './js/settings.js',
  './js/signed_in_worker.js',
  './js/signin_state.js',
  './js/state_manager.js',
  './app_offline_sw.js',
  './index.html',
  './manifest.webmanifest'
];

self.addEventListener('install', event => {
    console.log('Installing SW, caching: ', URLS_TO_CACHE)
  event.waitUntil(
    caches.open(CACHE_VERSION)
      .then(cache => cache.addAll(URLS_TO_CACHE))
  );
});

self.addEventListener('fetch', event => {
    console.log('Fetching: ', event.request.url);
  event.respondWith(
    caches.match(event.request)
      .then(response => response || fetch(event.request))
  );
});


// handle updates
self.addEventListener('activate', event => {
  event.waitUntil(
    caches.keys().then(cacheNames => {
      return Promise.all(
        cacheNames.map(cache => {
          if (cache !== CACHE_VERSION) {
            return caches.delete(cache);
          }
        })
      );
    })
  );
});