Read environment variables in Node.js

Question

Is there a way to read environment variables in Node.js code?

Like for example Python's os.environ['HOME'].

Answer 1

process.env.ENV_VARIABLE

Where ENV_VARIABLE is the name of the variable you wish to access.

See Node.js docs for process.env.

Answer 2

When using Node.js, you can retrieve environment variables by key from the process.env object:

for example

var mode   = process.env.NODE_ENV;
var apiKey = process.env.apiKey; // '42348901293989849243'

Here is the answer that will explain setting environment variables in node.js

Answer 3

To retrieve environment variables in Node.JS you can use process.env.VARIABLE_NAME, but don't forget that assigning a property on process.env will implicitly convert the value to a string.

Avoid Boolean Logic

Even if your .env file defines a variable like SHOULD_SEND=false or SHOULD_SEND=0, the values will be converted to strings (“false” and “0” respectively) and not interpreted as booleans.

if (process.env.SHOULD_SEND) {
 mailer.send();
} else {
  console.log("this won't be reached with values like false and 0");
}

Instead, you should make explicit checks. I’ve found depending on the environment name goes a long way.

 db.connect({
  debug: process.env.NODE_ENV === 'development'
 });

Answer 4

If you want to use a string key generated in your Node.js program, say, var v = 'HOME', you can use process.env[v].

Otherwise, process.env.VARNAME has to be hardcoded in your program.

Answer 5

You can use the dotenv package to manage your environment variables per project:

• Create a .env file under the project directory and put all of your variables there as VAR_NAME=value pairs.
• Add require('dotenv').config(); to the top of your application entry file.

Now you can access your environment variables with process.env.VAR_NAME.

Answer 6

Using process.env. If Home is your env variable name then Try this:

const HOME = process.env.HOME;

Or

const { HOME } = process.env;

Answer 7

If you want to see all the Enviroment Variables on execution time just write in some nodejs file like server.js:

console.log(process.env);

Answer 8

You first have to install the following library, ensuring you are in the root of your project:

npm i dotenv

Next create your .env file ensuring it is in the root of your project directory, here is an example of how to add a new variable within it:

# test variable
TESTVARIABLE='The test variable is working, value pulled from local!'

Next you would have to reference this module/library in the file you wish to use the environment variable e.g index.js, at the top of the file add the following code:

require("dotenv").config();

Now you can use/obtain the environment variable like so:

const message = process.env['TESTVARIABLE'];

Answer 9

#Install the npm package dotenv

npm i dotenv

#Let's create a file .env

#Inside the .env file what I will do is that...

DATABASE_CONFIG={"host":"localhost","user":"root","password":"password123"}

BASE_URL=192.168.163.128;

#Now we will create the index.js file and it contains like the following ways...

require('dotenv').config();

// Example - 01: const url=process.env.BASE_URL; console.log("Base Url which is reading from env : ${url}")

//Example - 02:

const databaseConfigString = process.env.DATABASE_CONFIG; console.log(databaseConfigString);

let databaseConfig;

try { databaseConfig = JSON.parse(databaseConfigString); } catch (error) { console.error('Error parsing DATABASE_CONFIG:', error.message); }

if (databaseConfig) { console.log('Database Config:', databaseConfig); console.log('Host:', databaseConfig.host); console.log('User:', databaseConfig.user); console.log('Password:', databaseConfig.password); }

https://www.youtube.com/watch?v=gzCZ7l4pK3Y

Answer 10

addon ensure envs are there before imports read them:

import { a} from "A.mjs";
console.log('env checks here')
import {b} from "B.mjs";

Despite log is before the import, nodejs will hoist all imports to the top and process respective modules. If any module eg B.mjs imports an env variable it will run before the env checks. thus one cannot use destructure { foo } = process.env but use a preinit script or dynamically import:

import myEnvCheck ... from ...;
myEnvCheck(["env1","env2"])

// now use a dynamic import which is run when reached / not hoisted; 
import("index.js").catch(...);

alternatively you can use import "dotenv/config"; in index.js and put the envs in a file instead

Answer 11

Why not use them in the Users directory in the .bash_profile file, so you don't have to push any files with your variables to production?