Using environment variables with .env

tl;dr

npm i -D dotenv

define vars in .env file

ACCESS_TOKEN=j1v7qstp59eodbn79tsp
CLEINT_KEY=wp2aksuvduasepd2edre2rd
CLIENT_SECRET=227tasgvdvqid2tedt2e

use vars in your code app.js file

add a .env-sample and commit that, .gitignore the actual .env file

const connection = new API({
	api_token: process.env.ACCESS_TOKEN,
	client_key: process.env.CLEINT_KEY,
	client_secret: process.env.CLIENT_SECRET
})
// .env
SECRET_KEY=SuperSecretKey90965443241
require('dotenv').config() // require config
require('./../server/index') // entry point

console.info(process.env.SECRET_KEY);

Set env variables by passing them as an argument

# *nix
NODE_ENV=development node app.js

For Windows you need to use the set keyword

# windows
set NODE_ENV=development&& node app.js 

cross-env can be used for cross-platform env variables

npm insall cross-env --save-dev

npx cross-env NODE_ENV=development node app.js
npx cross-env NODE_ENV=development PORT=3000 node app.js

package.json

"scripts": {
	"dev": "NODE_ENV=development PORT=3000 node app"
}
  • .js is optional in app.js
  • "cross-env NODE_ENV=development PORT=3000 node app" will run on any operating system

Sample .env

NODE_ENV=development
PORT=3000
HOST
const {
	NODE_ENV, PORT, HOST
} = process.env

console.info(
	NODE_ENV, PORT, HOST
);
# Load env variables and pass them along as cofig vars in terminal
eval $(cat .env) node app.js

# make values available to current Shell
export $(cat .env) && node app.js
require('dotenv').config() // by adding this one line you can now do `node app.js` and it'll have your vars

const {
	NODE_ENV, PORT, HOST
} = process.env

console.info(
	NODE_ENV, PORT, HOST
);
node app.js