web2019/static/sw.js

var CACHE_NAME = 'ml-03';
var urlsToCache = [
  '/css/bootstrap-4.3.1.min.css',
  '/css/styles.css',
  '/js/jquery-3.3.1.slim.min.js',
  '/js/bootstrap-4.3.1.min.js',
  '/js/popper-1.14.7.min.js',
];

self.addEventListener('install', function(event) {
  console.log('[SW] Install');
  event.waitUntil(
    caches.open(CACHE_NAME)
      .then(function(cache) {
        console.log('[SW] add to cache');
        return cache.addAll(urlsToCache);
      })
  );
});

self.addEventListener('fetch', function (event) {
  console.log('[SW] Fetch');
  event.respondWith(
    caches.match(event.request).then(function (response) {
      return response || fetch(event.request);
    })
  );
});

self.addEventListener('message', function (event) {
  if (event.data.action === 'skipWaiting') {
    self.skipWaiting();
    caches.delete(CACHE_NAME);
  }
});