https://www.italiaoggi.it/firebase-messaging-sw.js

1if('function' === typeof importScripts) {
2    const firebaseVersion = '8.9.1';
3
4    importScripts("https://www.gstatic.com/firebasejs/" + firebaseVersion + "/firebase-app.js");
5    importScripts("https://www.gstatic.com/firebasejs/" + firebaseVersion + "/firebase-messaging.js");
6    addEventListener('message', onMessage);
7
8    function onMessage(e) {
9        // do some work here
10    }
11
12    // Initialize the Firebase app in the service worker by passing in the
13    // messagingSenderId.
14    const firebaseConfig = {
15      apiKey: "AIzaSyBSyn3KNz3yFduBSsAYC43cC3iMzMG4CGQ",
16	  authDomain: "mapp-web-push-io.firebaseapp.com",
17	  projectId: "mapp-web-push-io",
18	  storageBucket: "mapp-web-push-io.firebasestorage.app",
19	  messagingSenderId: "1007819306117",
20	  appId: "1:1007819306117:web:a87d64b01a84f1a069a5ec"
21    };
22
23    firebase.initializeApp(firebaseConfig);
24
25    // Retrieve an instance of Firebase Messaging so that it can handle background messages.
26    const messaging = firebase.messaging();
27
28    messaging.onBackgroundMessage(function(payload) {
29        // do some work here
30
31        /*
32        if (!payload.notification && payload.webpush && payload.webpush.notification) {
33            const notificationTitle = payload.webpush.notification.title;
34            const notificationOptions = payload.webpush.notification;
35
36            if (notificationOptions.image && !notificationOptions.icon) {
37                notificationOptions.icon = notificationOptions.image;
38            }
39
40            return self.registration.showNotification(
41                notificationTitle,
42                notificationOptions
43            );
44        }
45        */
46    });
47}