process.env.PORT and process.env.NODE_ENV are both returning undefined

Question

I am trying to learn MERN and have hit an issue straight away

 App.listen(process.env.PORT, () => {
console.log(`Server started on PORT: ${process.env.PORT} in ${process.env.NODE_ENV} mode.`)
})

returns "Server started on PORT: undefined in undefined mode."

Here is structure

backend:

config:

  config.ev

App.js

server.js

App.js> const express = require('express); const App = express(); module.exports = App

server.js> `const App = require('./App');

const dotenv = require('dotenv')

// Config set up

dotenv.config({ path: 'backend\config\config.env'})

App.listen(process.env.PORT, () => { console.log(Server started on PORT: ${process.env.PORT} in ${process.env.NODE_ENV} mode.) })`

config.env PORT = 4000 NODE_ENV = DEVELOPMENT

Answer 1

to require dotenv, use this instead of what you have currently

const dotenv = require("dotenv").config();

i also noticed some typos in your question like the missing quotation mark when you required express but i assume this was a typo from writing it on here and not in your actual code.

and you can find more info on dotenv here