socket.io not loading on heroku - node.js

Question

I'm using node.js, express, socket.io, mongodb, mongoose, mongolab and heroku to build simple chat.
Everything work great on the localhost (without heroku), but when I deploy my app on the heroku the socket.io.js not loading.
https://prnt.sc/gm6fz0
I've read about 10-20 other similiar questions and tried other variations, but socket.io.js still won't load.
app.js - server side
var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');
var app = require('express')();
var server = require('http').createServer(app);
var io = require('socket.io')(server);
var mongoose = require('mongoose');
var mongodb = require('mongodb');
server.listen(8080);
var uri = 'mongodb://username:password#ds141264.mlab.com:41264/chat';
var index = require('./routes/index');
var users = require('./routes/users');
mongoose.connect(uri, function(err){
if(err) {
console.log(err);
} else {
console.log('connected to mongo db');
}
});
var db = mongoose.connection;
db.on('error', console.error.bind(console, 'connection error:'));
db.once('open', function callback () {
var chatSchema = mongoose.Schema ({
msg: String,
created: {type: String, default: function(){return new Date()}}
});
var Chat = mongoose.model('Message', chatSchema);
io.on('connection', function(socket){
console.log('a user connected');
var query = Chat.find({});
query.sort({'_id': -1}).limit(10).exec(function(err, docs){
if (err) throw err;
console.log('sending old msgs');
socket.emit('load old msgs', docs);
});
socket.on('disconnect', function(){
console.log('user disconnected');
});
socket.on('chat', function(msg){
console.log('message: ' + msg);
var newMsg = new Chat({ msg: msg });
newMsg.save(function(err){
if(err) throw err;
io.emit('chat', msg);
});
});
});
});
app.use(express.static(__dirname + '/public'));
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');
// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use('/', index);
app.use('/users', users);
// catch 404 and forward to error handler
app.use(function(req, res, next) {
var err = new Error('Not Found');
err.status = 404;
next(err);
});
// error handler
app.use(function(err, req, res, next) {
// set locals, only providing error in development
res.locals.message = err.message;
res.locals.error = req.app.get('env') === 'development' ? err : {};
// render the error page
res.status(err.status || 500);
res.render('error');
});
module.exports = app;
global.js - client-side
var socket = io.connect();
$('#send-message-btn').click(function () {
var msg = $('#message-box').val();
socket.emit('chat', msg);
$('#message-box').val('');
return false;
});
socket.on('chat', function (msg) {
var dadd = new Date;
$('#messages').append($('<time>').text(dadd));
$('#messages').append($('<p>').text(msg));
});
socket.on('load old msgs', function(docs){
for(var i=0; i < docs.length; i++) {
$('#messages').prepend($('<p>').text(docs[i].msg));
$('#messages').prepend($('<time>').text(docs[i].created));
}
});

Answer 1

As Per the documentation provided on heroku (Apps using Socket.io should enable session affinity. If you plan to use node’s Cluster module or to scale your app to multiple dynos, you should also follow Socket.io’s multiple-nodes instructions.), You Basically have to execute the following command from you project directory.
heroku features:enable http-session-affinity
Best,
Daksh Miglani