Firebase Cloud Messaging foreground notification not working in Vue

Question

I've been working on integrating FCM in my Vue PWA app. So far I've managed to get the background notification working, but handling notifications when the app's on the foreground doesn't work. Here's my code.

src/App.vue

import firebase from './plugins/firebase'

export default {
  // Other stuff here...

  methods: {
    prepareFcm () {
      var messaging = firebase.messaging()
      messaging.usePublicVapidKey(this.$store.state.fcm.vapidKey)
      messaging.getToken().then(async fcmToken => {
        this.$store.commit('fcm/setToken', fcmToken)
        messaging.onMessage(payload => {
          window.alert(payload)
        })
      }).catch(e => {
        this.$store.commit('toast/setError', 'An error occured to push notification.')
      })
    }
  },

  mounted () {
    this.prepareFcm()
  }
}

public/firebase-messaging-sw.js

importScripts('https://www.gstatic.com/firebasejs/5.5.6/firebase-app.js')
importScripts('https://www.gstatic.com/firebasejs/5.5.6/firebase-messaging.js')

firebase.initializeApp({
  messagingSenderId: '123456789'
})

const messaging = firebase.messaging()

messaging.setBackgroundMessageHandler(function (payload) {
  return self.registration.showNotification(payload)
})

src/plugins/firebase.js

import firebase from '@firebase/app'
import '@firebase/messaging'
// import other firebase stuff...

const firebaseConfig = {
  apiKey: '...',
  authDomain: '...',
  databaseURL: '...',
  projectId: '...',
  storageBucket: '...',
  messagingSenderId: '123456789',
  appId: '...'
}

firebase.initializeApp(firebaseConfig)

export default firebase

What did I do wrong?

Answer 1

I've found a solution in another QA here in StackOverflow (which I can't find anymore for some reason).

Turns out you have to use Firebase API v7.8.0 instead of 5.5.6 like the docs said at the time. So those first two lines in public/firebase-messaging-sw.js should read like this instead:

importScripts('https://www.gstatic.com/firebasejs/7.8.0/firebase-app.js')
importScripts('https://www.gstatic.com/firebasejs/7.8.0/firebase-messaging.js')

Answer 2

Same issue i was faced. In my case firebase version in "package.json" and "firebase-messaging-sw.js" importScripts version was different. After set same version in "firebase-messaging-sw.js" importScripts which was in "package.json", my issue is resolved.

Before change

 **"package.json"**
 
 "firebase": "^8.2.1",
 
  **"firebase-messaging-sw.js"**

 importScripts('https://www.gstatic.com/firebasejs/7.8.0/firebase-app.js');
 importScripts('https://www.gstatic.com/firebasejs/7.8.0/firebase-messaging.js');

After change

 **"package.json"**

 "firebase": "^8.2.1",

 **"firebase-messaging-sw.js"**

 importScripts('https://www.gstatic.com/firebasejs/8.2.1/firebase-app.js');
 importScripts('https://www.gstatic.com/firebasejs/8.2.1/firebase-messaging.js');