Simple implementation of Laravel Echo in vanilla JS

laravel-echo-vanillajs.js

import Echo from 'laravel-echo';
import Pusher from 'pusher-js';
import axios from 'axios';

const token = 'your-access-token'
const authUrl = 'your-api-url/api/broadcasting/auth'
const pusherKey =  'your-pusher-key'
const pusherCluster = 'mt1'
const userId = 1
const privateChannel = 'App.Models.User.' + userId

const api = axios.create({
  headers: {
    "Authorization": `Bearer ${token}`
  }
})
 
window.Pusher = Pusher;
 
window.Echo = new Echo({
    broadcaster: 'pusher',
    key: pusherKey,
    cluster: pusherCluster,
    forceTLS: true,
    authorizer: (channel, options) => {
      return {
          authorize: (socketId, callback) => {
              api.post(authUrl, {
                  socket_id: socketId,
                  channel_name: channel.name
              })
              .then(response => {
                  callback(null, response.data);
              })
              .catch(error => {
                  callback(error);
              });
          }
      };
  },
});

window.Echo.private(privateChannel)
    .notification((notification) => {
        console.log(notification);
    });