Websocket error that is only occuring on live server - node.js

Question

Bizarre situation going on here with my websocket. It's giving me the error
Error during WebSocket handshake: Unexpected response code: 200
Which for the life of me I cannot figure out why.
I've set up a very similar server with the exact same code with the exact same servers & settings. The only difference is one server has a .com TLD while the other has a .sg TLD.
I've reduced it down to the simplest form, which is the below and the error is still happening. It's on the api side for sure and not the frontend as the frontend can connect to the .com TLD.
Below is all the code that I believe is related to the problem. If you think there might be other areas please ask and I will post other areas. It's hosted on AWS Elastic Beanstalk. I've also set the SSL cert to domain.com & *.domain.com
Does anybody know why this might be happening?
The bizarre thing to me is I literally set up a server with these exact settings and it's working perfectly fine.
server.js (start point in package.json)
'use strict';
(async function() {
// Server Setup
const WSServer = require('ws').Server;
const app = await require('./app.js');
const server = require('http').createServer(app);
const port = 3075;
// Create web socket server on top of a regular http server
const wss = new WSServer({
server: server
});
// Also mount the app here
// server.on('request', app);
let sendMessage = {
"connected":"connected to web socket",
}
wss.on('connection', function connection(ws) {
ws.send(JSON.stringify(sendMessage));
ws.on('message', async function incoming(message) {
let interval = setInterval(async () => {
console.log("ping");
ws.send(message);
}, 500);
});
ws.on('close', function close() {
console.log('/socket connection Closed');
});
});
server.listen(process.env.PORT || port, function() {
console.log(`AppName https/wss is listening on port ${process.env.PORT || port}`);
});
})();
app.js (removed much of the code that is irrelevant to this question)
module.exports = (async function() {
const {Config,Environments} = await require("./common/config");
const packageJson = require('./package.json');
// Handler
const AuthFunc = await require("./funcs/user/auth");
const BillingFunc = await require("./funcs/billing/billing");
const ObjectUtil = require("./utils/object");
const AccountStatusEnum = require("./enums/account-status").accountStatusEnum;
const sleep = require('util').promisify(setTimeout);
const {t} = require('./translations/i18n').i18n;
const {availableLanguages} = require('./translations/all');
// Simulate real API calls
const delayResponse = 250;// milliseconds
// ==============================================
// Base setup
// ==============================================
process.env.TZ = "Etc/GMT"
const express = require('express');
const app = express();
var expressWs = require('express-ws')(app);
const bodyParser = require('body-parser');
app.use(bodyParser.urlencoded({ extended: true }));
app.use(bodyParser.json());
app.use(require('express-useragent').express());
// Cors
app.use(async function(req, res, next) {
res.header("Access-Control-Allow-Origin", "*");
res.header("Access-Control-Allow-Headers", "Origin, X-Requested-With, Content-Type, Accept, auth-id, auth-token, x-csrf-token, _csrf");
res.header('Access-Control-Allow-Methods', 'PATCH, POST, GET, DELETE, OPTIONS');
next();
});
// ==============================================
// Auth
// ==============================================
const normRoute = (req, res, next) => {
req.body = (req.body != undefined && req.body != null) ? ObjectUtil.toCamelCaseKeys(req.body) : req.body;
response(req,res,next(req));
}
// Does not need to be logged in but passes user info if logged in
const passRoute = async (req, res, next) => {
authRoute(req, res, next, AccountStatusEnum.any, true);
}
const authRoute = async (req, res, next, minimumStatus, passRoute) => {
req.body = (req.body != undefined && req.body != null) ? ObjectUtil.toCamelCaseKeys(req.body) : req.body;
let authId = (req.headers['auth-id'] !== undefined) ? req.headers['auth-id'] :"";
let authToken = (req.headers['auth-token'] !== undefined) ? req.headers['auth-token'] : "";
let r = await AuthFunc.authUser(
req,
req.ip,
req.useragent,
authId,
authToken,
minimumStatus,
);
if(r.err.code){
if(r.err.authError && passRoute){
response(req,res,next(req,null));
return false;
}else{
response(req,res,r);
return false;
}
}
let user = r.res.user;
r = await BillingFunc.updateSubStatus(req,user);
if(r.err.code){ response(req,res,r); return false; }
if(r.res.userStatus !== undefined){
user.status = r.res.userStatus;
}
response(req,res,next(req,user));
}
// ===============================================================
// Routes
// ===============================================================
app.get('/', function(req, res) {
res.send(
'<html>'+
'<head></head>'+
'<body>'+
'API is running <br>'+
'App: '+Config.FrontEnd.AppName+'<br>'+
'Env: '+Config.Env+'<br>'+
'Version: '+packageJson.version+'<br>'+
'</body>'+
'</html>'
);
});
// ==============================================
// Response type
// ==============================================
const response = async (req,res,obj) => {
await obj;
Promise.resolve(obj).then(function(val) {
if(delayResponse >= 1 && (Config.Env === Environments.Local)){
setTimeout(function(){
resume(req,res,val);
}, delayResponse);
return true;
}
resume(req,res,val);
});
}
const resume = (req,res,obj) => {
obj = (obj === undefined) ? {} : obj;
var status = (obj.status !== undefined) ? obj.status : 200;
// Let status override settings
if(obj.status === undefined){
if((obj.err.code)){
status = 400;
}else if(obj.res === undefined || ObjectUtil.isEmpty(obj.res)){
// status = 204;
}
}
let json = {};
json.err = obj.err;
json.res = obj.res;
json = ObjectUtil.toCamelCaseKeys(json);
res.status(status).json(json);
}
// ==============================================
// Return the app
// ==============================================
return app;
})();
package.json
{
"name": "name-api",
"version": "1.17.0",
"description": "name-api",
"main": "server.js",
"dependencies": {
"axios": "^0.21.1",
"cookie-parser": "^1.4.4",
"express": "^4.17.1",
"express-session": "^1.17.1",
"express-useragent": "^1.0.13",
"express-ws": "^4.0.0",
"googleapis": "^50.0.0",
"mocha": "^8.0.1",
"mysql": "github:mysqljs/mysql",
"nodemailer": "^6.4.6",
"query-string": "^6.12.1",
"stripe": "^8.60.0",
"ws": "^7.4.3"
},
"devDependencies": {},
"scripts": {
"test": "mocha",
"start": "node server.js"
},
"repository": {
"type": "git",
"url": "git+https://github.com/..."
},
"author": "",
"license": "ISC",
"bugs": {
"url": "https://github.com/..."
},
"homepage": "https://github.com/..."
}

Answer 1

Problem solved.
It was a load balancer issue. Apparently this doesn't work well with Classic Load Balancer. I believe it's due to the way it's requested.
Changing over to a Application Load balancer fixed the issue for me.