app.js

const express = require('express')
const app = express();
const server = require('http').Server(app);
const io = require('socket.io').listen(server);
const db = require('./modules/db.js');

const port = 3004;

/*
Copy the following session code
This code takes the username if the session is not set and sets the session
After that, username should be accessed using req.sess.username variable
or using socket.request.sess.username inside sockets
Do not change the value of req.sess.username anywhere in your code
The following code is required to integrate the game on the teknack servers
Use http://localhost:3000/unsetSession to unset session and reset username
Change the environment variable during deployment
*/

//********************Session Code Start*******************************//
//Copy from here
// const environment = "production";  ///change it to "production" when the game is deployed on the teknack servers
const environment = "development";

const sessions = require("client-sessions");
const bodyParser = require('body-parser');
app.use(bodyParser.urlencoded({ extended: false }));
app.use(bodyParser.json());

const sessionMiddleware = sessions({
    cookieName: 'sess',
    secret: 'dws9iu3r42mx1zvh6k5m',
    duration: 2 * 60 * 60 * 1000,
    activeDuration: 1000 * 60 * 60
})

app.use(sessionMiddleware);

app.post("/setSession", function (req, res) {
    req.sess.username = req.body.username;    // username is stored in sess variable
    console.log(req.sess.username + " logged in");  // username can be accessed using req.sess.username
    res.sendStatus(200);
});

app.get("/unsetSession", function (req, res) {
    if (environment == "development") {
        req.sess.username = null;
        res.sendStatus(200);
    } else if (environment == "production") {
        res.sendStatus(400);
    }
});


app.use(function (req, res, next) {
    if (!req.sess.username) {
        let login = `<script>
        var username = prompt("Enter username");
        if (username) {
            var xhttp = new XMLHttpRequest();
            xhttp.onreadystatechange = function () {
                if (this.readyState == 4 && this.status == 200) {
                    window.location = "/";
                }
            };
            xhttp.open("POST", "/setSession", true);
            xhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
            xhttp.send("username=" + username);

        }
    </script>`;
        if (environment == "development") {
            res.send(login);
        } else if (environment == "production") {
            res.redirect('https://teknack.in');
        }
    } else {
        next();
    }
});
//Copy till here
//********************Session Code End*******************************//

//If sockets are used
//Copy the following code to access username inside sockets

io.use(function (socket, next) {
    sessionMiddleware(socket.request, socket.request.res, next);
});

//********************************************************************//
// Your code starts from here

app.use(express.static(__dirname + '/public'));

io.on('connection', function (socket) {

    socket.on('test', function () {
        var username = socket.request.sess.username;   // accessing username inside sockets
        console.log(username + " connected");
        console.log('test received');
    });
    socket.emit('hellosocket');

    socket.on('sendScore', function (score) {
        var username = socket.request.sess.username;
        var record = { name: username, score: score };
        db.insertScore(record);
    })

    socket.on('getHighScore', function () {
        db.getScore(function (score) {
            socket.emit('sendHighScore', score);
        })
    })

});


server.listen(port, function () {
    console.log('App listening on port '+port.toString()+'!')
})