Heroku: My routes still pointing to localhost when deployed - mongodb

Question

I set up my NODE_ENV to production under APP>Settings>Config Vars on Heroku and set up a mongo.json file in my root directory:
{
"development": {
"host": "127.0.0.1:27017",
"dbName": "hillfinder"
},
"production": {
"PRODUCTION_DB_DSN": "mongodb+srv://***credentials***#hillfinder-qjxuo.mongodb.net/production?retryWrites=true&w=majority"
}
}
But it's still pointing to localhost:
This is the my server/index.js:
const express = require('express');
require('dotenv').config();
const nextJS = require('next');
var cookieParser = require('cookie-parser');
var session = require('express-session');
var MongoStore = require('connect-mongo')(session);
var bodyParser = require('body-parser');
var auth = require('./lib/auth');
var cors = require('cors');
var morgan = require('morgan');
var HttpStatus = require('http-status-codes');
var PORT = process.env.PORT || 8016;
const { isBlockedPage, isInternalUrl } = require('next-server/dist/server/utils');
function NODE_ENVSetter(ENV) {
var environment,
environments = {
production: () => {
environment = process.env.PRODUCTION_DB_DSN;
console.log(`We are currently in the production environment: ${environment}`);
return environment;
},
test: () => {
environment = process.env.TEST_DB_DSN;
console.log(`We are currently in the test environment: ${environment}`);
return environment;
},
default: () => {
environment = process.env.DEVELOPMENT_DB_DSN;
console.log(`We are currently in the development environment: ${environment}`);
return environment;
}
};
(environments[ENV] || environments['default'])();
return environment;
}
var db = NODE_ENVSetter('production');
var mongoose = require('mongoose');
function errorHandler(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 : {};
// Log error
console.error(err.stack);
// Render the error page
res.status(err.status || 500);
// Default error message by HTTP code
res.render('error', {
title: HttpStatus.getStatusText(err.status),
message: HttpStatus.getStatusText(err.status)
});
}
async function start() {
const dev = process.env.NODE_ENV !== 'production';
const app = nextJS({ dev });
const server = express();
await app
.prepare()
.then(() => {
mongoose.connect(db, { useNewUrlParser: true });
mongoose.Promise = global.Promise;
mongoose.connection
.on('connected', () => {
console.log(`Mongoose connection open on ${db}`);
})
.on('error', err => {
console.log(`Connection error: ${err.message}`);
});
})
.catch(err => {
console.error(err);
});
server.set('view engine', 'html');
server.use('/uploads', express.static(__dirname + '/uploads'));
server.use(bodyParser.urlencoded({ limit: '50mb', extended: false }));
server.use(bodyParser.json({ limit: '50mb' }));
server.use(morgan('dev'));
server.use(cookieParser());
server.use(
session({
secret: 'very secret 12345',
resave: false,
saveUninitialized: false,
store: new MongoStore({ mongooseConnection: mongoose.connection })
})
);
server.use(auth.initialize);
server.use(auth.session);
server.use(auth.setUser);
console.log('auth.setUser ', auth.setUser);
server.use(cors());
server.use('/users', require('./users'));
server.use('/images', require('./images'));
// Redirect all requests to main entrypoint pages/index.js
server.get('/*', async (req, res, next) => {
try {
const pathName = req.originalUrl;
if (isInternalUrl(req.url)) {
return app.handleRequest(req, res, req.originalUrl);
}
if (isBlockedPage(pathName)) {
return app.render404(req, res, req.originalUrl);
}
req.locals = {};
req.locals.context = {};
const html = await app.renderToHTML(req, res, '/', {});
// Handle client redirects
const context = req.locals.context;
if (context.url) {
return res.redirect(context.url);
}
// Handle client response statuses
if (context.status) {
return res.status(context.status).send();
}
// Request was ended by the user
if (html === null) {
return;
}
app.sendHTML(req, res, html);
} catch (e) {
next(e);
}
});
// error handler
server.use(function(err, req, res, next) {
// set locals, only providing error in development
res.locals.errorStatus = err.status;
res.locals.errorMessage = err.message;
res.locals.error = req.app.get('env') === 'development' ? err : {};
// render the error page
console.log('err.status ', err.status);
res.status(err.status).send(err.message);
});
server.listen(PORT, err => {
if (err) throw err;
console.log(`> Ready and listening on http://localhost:${PORT}`);
});
}
start();
How would I fix that so I can log on to MongoDB atlas?
Thank you in advance!