Using environment variables with .env

April 4, 2019

tl;dr

code

npm i -D dotenv

define vars in .env file

code

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

code

const connection = new API({
  api_token: process.env.ACCESS_TOKEN,
  client_key: process.env.CLEINT_KEY,
  client_secret: process.env.CLIENT_SECRET,
});

code

// .env
SECRET_KEY = SuperSecretKey90965443241;

code

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

code

# *nix
NODE_ENV=development node app.js

For Windows you need to use the set keyword

code

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

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

code

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

code

"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

code

NODE_ENV=development
PORT=3000
HOST

code

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

console.info(NODE_ENV, PORT, HOST);

code

# 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

code

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);

code

node app.js

Using environment variables with .env

Links