sever.js

const Pusher = require('pusher')
const uuid = require('uuid/v1')
const ngrok = require('ngrok')

var pusher = new Pusher({
  appId: '385685',
  key: '955f28f383404945239b',
  secret: 'c58baaf698167224517f',
  cluster: 'eu',
  encrypted: true
})

ngrok.connect(8080, (err, url) => {
  console.log(url)
})
const app = express()
app.engine('handlebars', exphbs({ defaultLayout: 'main' }))
app.set('view engine', 'handlebars')
app.use(bodyParser.json())
app.use(bodyParser.urlencoded({ extended: false }))

app.get('/', (req, res) => {
  res.render('home', { layout: false, initialText: 'Hello' })
})

let whoIsTyping = null
let timer

const processEvent = (timestamp, event) => {
  const broadcast = function() {
    whoIsTyping = null
    pusher.trigger('typing-events', 'update-whoIsTyping', {
      whoIsTyping
    })
  }
  if (whoIsTyping === event.user_id) {
    clearTimeout(timer)
    timer = setTimeout(broadcast, 2000)
    return
  }
  whoIsTyping = event.user_id
  pusher.trigger('typing-events', 'update-whoIsTyping', {
    whoIsTyping
  })

  timer = setTimeout(broadcast, 2000)
  console.log('timer', timer)
}

const findOnInputEvents = events =>
  events.filter(event => event.event === 'client-oninput')

app.post('/client_event', function(req, res) {
  var timestamp = req.body.time_ms
  var events = req.body.events
  events.forEach(event => processEvent(timestamp, event))
  res.sendStatus(200)
})

app.post('/pusher/auth', function(req, res) {
  console.log(req.body)
  const user_id = uuid()
  console.log(user_id)
  var presenceData = {
    user_id
  }
  const auth = pusher.authenticate(
    req.body.socket_id,
    req.body.channel_name,
    presenceData
  )
  res.send(auth)
})

app.listen(8080)