Hi, I have a nodejs (socket.io) app running on a dedicated Ubuntu server; a good friend of mine introduced me to app engine. As such, I have created and deployed a nodejs app as per instructions.

I can access the app via http as a websever, express.js is handling all of that.

However, when I try to access the app via a socket, it fails, and I do not understand why.

I have attached my code:

const logger = require('winston');
const express = require("express");
const socket = require("socket.io");
const fs = require('fs');
const http = require('http');

// my utility module
const functions = require('./my_modules/functions');
const utils = require('./my_modules/utils');


// App setup
const PORT = 8080;

// Logger config
logger.remove(logger.transports.Console);
logger.add(new logger.transports.Console, { colorize: true, timestamp: true });

const app = express();

app.use(function(req, res, next) {
    res.header('Access-Control-Allow-Origin', '*');
    res.header('Access-Control-Allow-Methods', 'OPTIONS, GET, PUT, POST, DELETE');
    res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept");
    next();
});

// this inserts a json middleware into the current app
// which parse the request, and populate the request.body property, i.e req.body
app.use(express.json());

// parse url encoded inputs, i.e) key=value&key=value and populate the req.body property
// this is usefull, when we are not using json
app.use(express.urlencoded({ extended: true }));

let server = http.createServer(app);

server.listen(PORT, () => {
    logger.info('SocketIO > Server listening on port: ' + PORT);
});


// Socket setup
const io = socket(server);

// const staffs = [];
// const riders = [];
const devices = [];

// home entry
app.get('/', (req, res) => {
    console.log("devices", devices);
    res.status(200).send(utils.response(true, "Hello World"));
});


io.on('connection', (socket) => {

    // log on server that app has been connected
    logger.info('SocketIO > Connected socket ' + socket.id);

    // notifies, the client of successful connection
    socket.emit('connection', "You're connected to the node server buddy");

    // sets the initial parameter of an object
    socket.on('init', (data) => {
        let obj = JSON.parse(data);
        devices.push({
            socket: socket,
            userid: obj.userid,
            platform: "riderapp"
        });

        // if(obj.type == "rider"){
        //     riders.push({
        //         socket: socket,
        //         userid: obj.userid,
        //         platform: "riderapp"
        //     });
        // } else {
        //     staffs.push({
        //         socket: socket,
        //         userid: obj.userid,
        //         platform: "staffapp"
        //     });
        // }

    });

    // lsitens, when a socket is closed
    socket.on('disconnect', () => {
        let index = 0;
        staffs.forEach(staff => {
            if(staff.socket.id === socket.id){
                staffs.splice(index, 1);
            }
            index++;
        });

        let index2 = 0;
        riders.forEach(rider => {
            if(rider.socket.id === socket.id){
                riders.splice(index2, 1);
            }
            index2++;
        });

        logger.info('SocketIO > Disconnected socket ' + socket.id);
    });
});