server.js

    // taken from: https://pusher.com/tutorials/react-websockets
    // npm install --save axios body-parser cors express pusher pusher-js
		
    const Pusher = require('pusher');
    const express = require('express');
    const bodyParser = require('body-parser');
    const cors = require('cors');

    const app = express();

    app.use(cors());
    app.use(bodyParser.urlencoded({extended: false}));
    app.use(bodyParser.json());
    const pusher = new Pusher({
      appId: '818136',
      key: 'dffbab583e3f0e41aea3',
      secret: '9e37ae462d31e46a47b3',
      cluster: 'us2',
      encrypted: true
    });
    // pusher.trigger('reactWebRTC', 'chat', {
    //   "message": "hello world"
    // })

    app.set('PORT', process.env.PORT || 3000);

    app.post('/offer', (req, res) => {
      const payload = req.body;
      pusher.trigger('reactWebRTC', 'offer', payload);
      res.send(payload)
    });

    app.post('/answer', (req, res) => {
      const payload = req.body;
      pusher.trigger('reactWebRTC', 'answer', payload);
      res.send(payload)
    });

    app.post('/candidate', (req, res) => {
      const payload = req.body;
      pusher.trigger('reactWebRTC', 'candidate', payload);
      res.send(payload)
    });

    app.listen(app.get('PORT'), () => 
      console.log('Listening at ' + app.get('PORT')))