index.js

const express = require('express')
const app = express()
const bodyParser = require('body-parser')
const cors = require('cors')
const dotEnv = require('dotenv')
const mongoose = require('mongoose')
const socket = require('socket.io')
const redis = require('redis')
const { promisify } = require('util')
const http = require('http')
// const https = require('https')
// const fs = require('fs')
const morgan = require('morgan')

// Middleware
app.use(bodyParser.json())
app.use(
  bodyParser.urlencoded({
    extended: true
  })
)
dotEnv.config()
app.use(cors({
  origin: function (origin, callback) {
    callback(null, true)
  },
  credentials: true
}))
app.use(morgan('dev'))
// Connect to Database
mongoose.connect(
  process.env.DB_CONNECTION, {
    useNewUrlParser: true,
    useUnifiedTopology: true,
    useFindAndModify: false
  }
)
  .then(() => console.log('Connected to DB'))
  .catch(err => {
    console.log(err)
  })
// Connecting to redis
const client = redis.createClient(process.env.REDIS_URL)
client.on('connect', () => {
  console.log('Redis Client Connected')
})
client.on('error', (err) => {
  console.log('Something went wrong ' + err)
})
// Creating callbacks to promises
const redisSet = promisify(client.set).bind(client)
const redisGet = promisify(client.get).bind(client)
const redisDel = promisify(client.del).bind(client)

// setting up HTTP(s) servers
const httpServer = http.createServer(app)
const server = httpServer.listen(process.env.PORT || 3000, () => {
  console.log('listening on HTTP')
})

/*
const privateKey  = fs.readFileSync('./sslcert/privkey.pem', 'utf8');
const certificate = fs.readFileSync('./sslcert/cert.pem', 'utf8');
const httpsServer = https.createServer({key: privateKey, cert: certificate}, app);
const server = httpsServer.listen(process.env.SSL_PORT || 3443);
console.log("Listening on HTTPS");
*/

const io = socket(server)

// Calling all routes
const authRoute = require('./routes/auth')
const eventHandler = require('./routes/eventHandler')
const actionHandler = require('./routes/actionHandler')
const questionHandler = require('./routes/questionHandler')
const optionHandler = require('./routes/optionHandler')

// Array Functions
const increment = async (optionId) => {
  try {
    let stat = await redisGet(optionId)
    console.log(stat)
    if (stat == null) {
      await redisSet(optionId, 1)
      return {
        stat: 1,
        _id: optionId
      }
    }
    stat = parseInt(stat)
    stat += 1
    console.log('Updated Stat' + stat)
    await redisSet(optionId, stat)
    return {
      stat: stat,
      _id: optionId
    }
  } catch (err) {
    console.log(err)
  }
}

const clean = async (optionId) => {
  try {
    for (const _id of optionId) {
      await redisDel(_id)
    }
  } catch (err) {
    console.log(err)
  }
}

const restore = async (optionIds) => {
  try {
    for (const _id of optionIds) {
      await redisSet(_id, 0)
    }
  } catch (err) {
    console.log(err)
  }
}

io.on('connection', sc => {
  console.log('Connected')
  sc.on('disconnect', () => {
    console.log('Disconnected')
  })
  sc.on('option', async optionId => {
    const dataToEmit = await increment(optionId)
    console.log(dataToEmit)
    io.sockets.emit('all options', dataToEmit)
  })
  sc.on('next question', data => {
    io.sockets.emit('next', data)
  })
  sc.on('close quiz', async data => {
    await clean(data)
    io.sockets.emit('quiz ended', data[0])
  })
  sc.on('reset options', async data => {
    await restore(data)
  })
})

app.use('/api/user', authRoute)
app.use('/api/events', eventHandler)
app.use('/api/actions', actionHandler)
app.use('/api/questions', questionHandler)
app.use('/api/options', optionHandler)