Web Push Receiver

message.js

import { Injectable }          from '@angular/core';
import { AngularFireDatabase } from 'angularfire2/database';
import { AngularFireAuth }     from 'angularfire2/auth';
import * as firebase from 'firebase';

// import 'rxjs/add/operator/take';
import { BehaviorSubject } from 'rxjs'

@Injectable()
export class MessagingService {

  messaging = firebase.messaging()
  currentMessage = new BehaviorSubject(null)

  constructor(private db: AngularFireDatabase, private afAuth: AngularFireAuth) { }


  updateToken(token) {
    this.afAuth.authState.subscribe(user => {
      if (!user) return;

      const data = { [user.uid]: token }
      this.db.object('fcmTokens/').update(data)
    })
  }

  getPermission() {
      this.messaging.requestPermission()
      .then(() => {
        console.log('Notification permission granted.');
        this.messaging.getToken().then(function(c){
          console.log(c);
        })
        return this.messaging.getToken()
      })
      
      .catch((err) => {
        console.log('Unable to get permission to notify.', err);
      });
    }

    receiveMessage() {
      console.log("Message received. ");
       this.messaging.onMessage((payload) => {
        console.log("Message received. ", payload);
        this.currentMessage.next(payload)
      });

    }

   
}