action-cable.js

// npm install --save actioncable
import * as ActionCable from 'actioncable/lib/assets/compiled/action_cable';

let myUid = '123';
let url = `ws://mesh-relay-in-us-1.herokuapp.com?uid=${myUid}`;
const cable = ActionCable.createConsumer(url);

const channel = cable.subscriptions.create({ channel: 'MeshRelayChannel', }, {
  connected: () => {
    console.log('connected');
  },

  disconnected: (data) => {
    console.log(data);
    console.log('disconnected');
  },

  rejected: (data) => {
    console.log(data);
    console.log('rejected');
  },

  received: (data) => {
    console.log(data);
    console.log('received');
  }
});

setTimeout(() => {
  channel.send({ to: myUid, message: 'test message', action: 'chat' });
}, 5000);