firebase-messaging-sw.js

// Give the service worker access to Firebase Messaging.
// Note that you can only use Firebase Messaging here, other Firebase libraries
// are not available in the service worker.
importScripts("https://www.gstatic.com/firebasejs/7.14.2/firebase-app.js");
importScripts("https://www.gstatic.com/firebasejs/7.14.2/firebase-messaging.js");

// Initialize the Firebase app in the service worker by passing in the
// messagingSenderId.
firebase.initializeApp({
  'messagingSenderId': '38226611639'
});

// Retrieve an instance of Firebase Messaging so that it can handle background messages.
const messaging = firebase.messaging();
// [END initialize_firebase_in_sw]
 
// If you would like to customize notifications that are received in the
// background (Web app is closed or not in browser focus) then you should
// implement this optional method.
// [START background_handler]
messaging.setBackgroundMessageHandler(function(payload) {
  console.log('[sw.js] Received background message ', payload);
  // Customize notification here
  var notificationTitle = 'Background Message Title';
  var notificationOptions = {
    body: 'Background Message body.',
    icon: '/firebase-logo.png'
  };

  return self.registration.showNotification(notificationTitle,
    notificationOptions);
});
// [END background_handler]

let cacheName = "MyCacheV";

let filesToCache = [
	"/",
	"/index.html",
	"js/main.js",
	"css/style.css"
];

self.addEventListener("install", function(event) {
	event.waitUntil(caches.open(cacheName).then((cache) =>{
		return cache.addAll(filesToCache);
	}));
});

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

self.addEventListener('activate', function(e) {
    console.log('service worker: Activate');
    e.waitUntil(
    caches.keys().then(function(keyList) {
      return Promise.all(keyList.map(function(key) {
        if (key !== cacheName) {
          console.log('service worker: Removing old cache', key);
          return caches.delete(key);
        }
      }));
    })
    );
    return self.clients.claim();
});