process.env.NODE_ENV is undefined

Question

I\'m trying to follow a tutorial on NodeJs. I don\'t think I missed anything but whenever I call the process.env.NODE_ENV the only value I get back is undefine

Answer 1

You can use the cross-env npm package. It will take care of trimming the environment variable, and will also make sure it works across different platforms.

In the project root, run:

npm install cross-env

Then in your package.json, under scripts, add:

"start": "cross-env NODE_ENV=dev node your-app-name.js"

Then in your terminal, at the project root, start your app by running:

npm start

The environment variable will then be available in your app as process.env.NODE_ENV, so you could do something like:

if (process.env.NODE_ENV === 'dev') {
  // Your dev-only logic goes here
}

Answer 2

process.env is a reference to your environment, so you have to set the variable there.

To set an environment variable in Windows:

SET NODE_ENV=development

on OS X or Linux:

export NODE_ENV=development

Answer 3

tips

in package.json:

"scripts": {
  "start": "set NODE_ENV=dev && node app.js"
 }

in app.js:

console.log(process.env.NODE_ENV) // dev
console.log(process.env.NODE_ENV === 'dev') // false
console.log(process.env.NODE_ENV.length) // 4 (including a space at the end) 

so, this may better:

"start": "set NODE_ENV=dev&& node app.js"

or

console.log(process.env.NODE_ENV.trim() === 'dev') // true

Answer 4

It is due to OS

In your package.json, make sure to have your scripts(Where app.js is your main js file to be executed & NODE_ENV is declared in a .env file).Eg:

"scripts": {
    "start": "node app.js",
    "dev": "nodemon server.js",
    "prod": "NODE_ENV=production & nodemon app.js"
  }

For windows

Also set up your .env file variable having NODE_ENV=development

If your .env file is in a folder for eg.config folder make sure to specify in app.js(your main js file)

const dotenv = require('dotenv'); dotenv.config({ path: './config/config.env' });

Answer 5

in package.json we have to config like below (works in Linux and Mac OS)

the important thing is "export NODE_ENV=production" after your build commands below is an example:

  "scripts": {
     "start": "export NODE_ENV=production && npm run build && npm run start-server",
     "dev": "export NODE_ENV=dev && npm run build && npm run start-server",
  } 

• for dev environment, we have to hit "npm run dev" command

• for a production environment, we have to hit "npm run start" command

Answer 6

In macOS for those who are using the express version 4.x.x and using the DOTENV plugin, need to use like this:

1. After installing the plugin import like the following in the file where you init the application: require('dotenv').config({path: path.resolve(__dirname+'/.env')});

2. In the root directory create a file '.env' and add the varaiable like:

   NODE_ENV=development or NODE_ENV = development