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<div align="center">
πŸŽ‰ announcing <a href="https://github.com/dotenvx/dotenvx">dotenvx</a>. <em>run anywhere, multi-environment, encrypted envs</em>.
</div>

&nbsp;

<div align="center">

<p>
  <sup>
    <a href="https://github.com/sponsors/motdotla">Dotenv is supported by the community.</a>
  </sup>
</p>
<sup>Special thanks to:</sup>
<br>
<br>
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  <div>
    <img src="https://res.cloudinary.com/dotenv-org/image/upload/v1661980709/warp_hi8oqj.png" width="230" alt="Warp">
  </div>
  <b>Warp is a blazingly fast, Rust-based terminal reimagined to work like a modern app.</b>
  <div>
    <sup>Get more done in the CLI with real text editing, block-based output, and AI command search.</sup>
  </div>
</a>
<br>
<a href="https://workos.com/?utm_campaign=github_repo&utm_medium=referral&utm_content=dotenv&utm_source=github">
  <div>
    <img src="https://res.cloudinary.com/dotenv-org/image/upload/c_scale,w_400/v1665605496/68747470733a2f2f73696e647265736f726875732e636f6d2f6173736574732f7468616e6b732f776f726b6f732d6c6f676f2d77686974652d62672e737667_zdmsbu.svg" width="270" alt="WorkOS">
  </div>
  <b>Your App, Enterprise Ready.</b>
  <div>
    <sup>Add Single Sign-On, Multi-Factor Auth, and more, in minutes instead of months.</sup>
  </div>
</a>
<hr>
</div>

# dotenv [![NPM version](https://img.shields.io/npm/v/dotenv.svg?style=flat-square)](https://www.npmjs.com/package/dotenv)

<img src="https://raw.githubusercontent.com/motdotla/dotenv/master/dotenv.svg" alt="dotenv" align="right" width="200" />

Dotenv is a zero-dependency module that loads environment variables from a `.env` file into [`process.env`](https://nodejs.org/docs/latest/api/process.html#process_process_env). Storing configuration in the environment separate from code is based on [The Twelve-Factor App](https://12factor.net/config) methodology.

[![js-standard-style](https://img.shields.io/badge/code%20style-standard-brightgreen.svg?style=flat-square)](https://github.com/feross/standard)
[![LICENSE](https://img.shields.io/github/license/motdotla/dotenv.svg)](LICENSE)
[![codecov](https://codecov.io/gh/motdotla/dotenv-expand/graph/badge.svg?token=pawWEyaMfg)](https://codecov.io/gh/motdotla/dotenv-expand)

* [🌱 Install](#-install)
* [πŸ—οΈ Usage (.env)](#%EF%B8%8F-usage)
* [🌴 Multiple Environments πŸ†•](#-manage-multiple-environments)
* [πŸš€ Deploying (encryption) πŸ†•](#-deploying)
* [πŸ“š Examples](#-examples)
* [πŸ“– Docs](#-documentation)
* [❓ FAQ](#-faq)
* [⏱️ Changelog](./CHANGELOG.md)

## 🌱 Install

```bash
# install locally (recommended)
npm install dotenv --save
```

Or installing with yarn? `yarn add dotenv`

## πŸ—οΈ Usage

<a href="https://www.youtube.com/watch?v=YtkZR0NFd1g">
<div align="right">
<img src="https://img.youtube.com/vi/YtkZR0NFd1g/hqdefault.jpg" alt="how to use dotenv video tutorial" align="right" width="330" />
<img src="https://simpleicons.vercel.app/youtube/ff0000" alt="youtube/@dotenvorg" align="right" width="24" />
</div>
</a>

Create a `.env` file in the root of your project (if using a monorepo structure like `apps/backend/app.js`, put it in the root of the folder where your `app.js` process runs):

```dosini
S3_BUCKET="YOURS3BUCKET"
SECRET_KEY="YOURSECRETKEYGOESHERE"
```

As early as possible in your application, import and configure dotenv:

```javascript
require('dotenv').config()
console.log(process.env) // remove this after you've confirmed it is working
```

.. [or using ES6?](#how-do-i-use-dotenv-with-import)

```javascript
import 'dotenv/config'
```

That's it. `process.env` now has the keys and values you defined in your `.env` file:

```javascript
require('dotenv').config()
// or import 'dotenv/config' if you're using ES6

...

s3.getBucketCors({Bucket: process.env.S3_BUCKET}, function(err, data) {})
```

### Multiline values

If you need multiline variables, for example private keys, those are now supported (`>= v15.0.0`) with line breaks:

```dosini
PRIVATE_KEY="-----BEGIN RSA PRIVATE KEY-----
...
Kh9NV...
...
-----END RSA PRIVATE KEY-----"
```

Alternatively, you can double quote strings and use the `\n` character:

```dosini
PRIVATE_KEY="-----BEGIN RSA PRIVATE KEY-----\nKh9NV...\n-----END RSA PRIVATE KEY-----\n"
```

### Comments

Comments may be added to your file on their own line or inline:

```dosini
# This is a comment
SECRET_KEY=YOURSECRETKEYGOESHERE # comment
SECRET_HASH="something-with-a-#-hash"
```

Comments begin where a `#` exists, so if your value contains a `#` please wrap it in quotes. This is a breaking change from `>= v15.0.0` and on.

### Parsing

The engine which parses the contents of your file containing environment variables is available to use. It accepts a String or Buffer and will return an Object with the parsed keys and values.

```javascript
const dotenv = require('dotenv')
const buf = Buffer.from('BASIC=basic')
const config = dotenv.parse(buf) // will return an object
console.log(typeof config, config) // object { BASIC : 'basic' }
```

### Preload

> Note: Consider using [`dotenvx`](https://github.com/dotenvx/dotenvx) instead of preloading. I am now doing (and recommending) so.
>
> It serves the same purpose (you do not need to require and load dotenv), adds better debugging, and works with ANY language, framework, or platform. – [motdotla](https://github.com/motdotla)

You can use the `--require` (`-r`) [command line option](https://nodejs.org/api/cli.html#-r---require-module) to preload dotenv. By doing this, you do not need to require and load dotenv in your application code.

```bash
$ node -r dotenv/config your_script.js
```

The configuration options below are supported as command line arguments in the format `dotenv_config_<option>=value`

```bash
$ node -r dotenv/config your_script.js dotenv_config_path=/custom/path/to/.env dotenv_config_debug=true
```

Additionally, you can use environment variables to set configuration options. Command line arguments will precede these.

```bash
$ DOTENV_CONFIG_<OPTION>=value node -r dotenv/config your_script.js
```

```bash
$ DOTENV_CONFIG_ENCODING=latin1 DOTENV_CONFIG_DEBUG=true node -r dotenv/config your_script.js dotenv_config_path=/custom/path/to/.env
```

### Variable Expansion

You need to add the value of another variable in one of your variables? Use [dotenv-expand](https://github.com/motdotla/dotenv-expand).

### Command Substitution

Use [dotenvx](https://github.com/dotenvx/dotenvx) to use command substitution.

Add the output of a command to one of your variables in your .env file.

```ini
# .env
DATABASE_URL="postgres://$(whoami)@localhost/my_database"
```
```js
// index.js
console.log('DATABASE_URL', process.env.DATABASE_URL)
```
```sh
$ dotenvx run --debug -- node index.js
[[email protected]] injecting env (1) from .env
DATABASE_URL postgres://yourusername@localhost/my_database
```

### Syncing

You need to keep `.env` files in sync between machines, environments, or team members? Use [dotenvx](https://github.com/dotenvx/dotenvx) to encrypt your `.env` files and safely include them in source control. This still subscribes to the twelve-factor app rules by generating a decryption key separate from code.

### Multiple Environments

Use [dotenvx](https://github.com/dotenvx/dotenvx) to generate `.env.ci`, `.env.production` files, and more.

### Deploying

You need to deploy your secrets in a cloud-agnostic manner? Use [dotenvx](https://github.com/dotenvx/dotenvx) to generate a private decryption key that is set on your production server.

## 🌴 Manage Multiple Environments

Use [dotenvx](https://github.com/dotenvx/dotenvx)

Run any environment locally. Create a `.env.ENVIRONMENT` file and use `--env-file` to load it. It's straightforward, yet flexible.

```bash
$ echo "HELLO=production" > .env.production
$ echo "console.log('Hello ' + process.env.HELLO)" > index.js

$ dotenvx run --env-file=.env.production -- node index.js
Hello production
> ^^
```

or with multiple .env files

```bash
$ echo "HELLO=local" > .env.local
$ echo "HELLO=World" > .env
$ echo "console.log('Hello ' + process.env.HELLO)" > index.js

$ dotenvx run --env-file=.env.local --env-file=.env -- node index.js
Hello local
```

[more environment examples](https://dotenvx.com/docs/quickstart/environments)

## πŸš€ Deploying

Use [dotenvx](https://github.com/dotenvx/dotenvx).

Add encryption to your `.env` files with a single command. Pass the `--encrypt` flag.

```
$ dotenvx set HELLO Production --encrypt -f .env.production
$ echo "console.log('Hello ' + process.env.HELLO)" > index.js

$ DOTENV_PRIVATE_KEY_PRODUCTION="<.env.production private key>" dotenvx run -- node index.js
[dotenvx] injecting env (2) from .env.production
Hello Production
```

[learn more](https://github.com/dotenvx/dotenvx?tab=readme-ov-file#encryption)

## πŸ“š Examples

See [examples](https://github.com/dotenv-org/examples) of using dotenv with various frameworks, languages, and configurations.

* [nodejs](https://github.com/dotenv-org/examples/tree/master/usage/dotenv-nodejs)
* [nodejs (debug on)](https://github.com/dotenv-org/examples/tree/master/usage/dotenv-nodejs-debug)
* [nodejs (override on)](https://github.com/dotenv-org/examples/tree/master/usage/dotenv-nodejs-override)
* [nodejs (processEnv override)](https://github.com/dotenv-org/examples/tree/master/usage/dotenv-custom-target)
* [esm](https://github.com/dotenv-org/examples/tree/master/usage/dotenv-esm)
* [esm (preload)](https://github.com/dotenv-org/examples/tree/master/usage/dotenv-esm-preload)
* [typescript](https://github.com/dotenv-org/examples/tree/master/usage/dotenv-typescript)
* [typescript parse](https://github.com/dotenv-org/examples/tree/master/usage/dotenv-typescript-parse)
* [typescript config](https://github.com/dotenv-org/examples/tree/master/usage/dotenv-typescript-config)
* [webpack](https://github.com/dotenv-org/examples/tree/master/usage/dotenv-webpack)
* [webpack (plugin)](https://github.com/dotenv-org/examples/tree/master/usage/dotenv-webpack2)
* [react](https://github.com/dotenv-org/examples/tree/master/usage/dotenv-react)
* [react (typescript)](https://github.com/dotenv-org/examples/tree/master/usage/dotenv-react-typescript)
* [express](https://github.com/dotenv-org/examples/tree/master/usage/dotenv-express)
* [nestjs](https://github.com/dotenv-org/examples/tree/master/usage/dotenv-nestjs)
* [fastify](https://github.com/dotenv-org/examples/tree/master/usage/dotenv-fastify)

## πŸ“– Documentation

Dotenv exposes four functions:

* `config`
* `parse`
* `populate`
* `decrypt`

### Config

`config` will read your `.env` file, parse the contents, assign it to
[`process.env`](https://nodejs.org/docs/latest/api/process.html#process_process_env),
and return an Object with a `parsed` key containing the loaded content or an `error` key if it failed.

```js
const result = dotenv.config()

if (result.error) {
  throw result.error
}

console.log(result.parsed)
```

You can additionally, pass options to `config`.

#### Options

##### path

Default: `path.resolve(process.cwd(), '.env')`

Specify a custom path if your file containing environment variables is located elsewhere.

```js
require('dotenv').config({ path: '/custom/path/to/.env' })
```

By default, `config` will look for a file called .env in the current working directory.

Pass in multiple files as an array, and they will be parsed in order and combined with `process.env` (or `option.processEnv`, if set). The first value set for a variable will win, unless the `options.override` flag is set, in which case the last value set will win.  If a value already exists in `process.env` and the `options.override` flag is NOT set, no changes will be made to that value. 

```js  
require('dotenv').config({ path: ['.env.local', '.env'] })
```

##### encoding

Default: `utf8`

Specify the encoding of your file containing environment variables.

```js
require('dotenv').config({ encoding: 'latin1' })
```

##### debug

Default: `false`

Turn on logging to help debug why certain keys or values are not being set as you expect.

```js
require('dotenv').config({ debug: process.env.DEBUG })
```

##### override

Default: `false`

Override any environment variables that have already been set on your machine with values from your .env file(s). If multiple files have been provided in `option.path` the override will also be used as each file is combined with the next. Without `override` being set, the first value wins. With `override` set the last value wins. 

```js
require('dotenv').config({ override: true })
```

##### processEnv

Default: `process.env`

Specify an object to write your secrets to. Defaults to `process.env` environment variables.

```js
const myObject = {}
require('dotenv').config({ processEnv: myObject })

console.log(myObject) // values from .env
console.log(process.env) // this was not changed or written to
```

### Parse

The engine which parses the contents of your file containing environment
variables is available to use. It accepts a String or Buffer and will return
an Object with the parsed keys and values.

```js
const dotenv = require('dotenv')
const buf = Buffer.from('BASIC=basic')
const config = dotenv.parse(buf) // will return an object
console.log(typeof config, config) // object { BASIC : 'basic' }
```

#### Options

##### debug

Default: `false`

Turn on logging to help debug why certain keys or values are not being set as you expect.

```js
const dotenv = require('dotenv')
const buf = Buffer.from('hello world')
const opt = { debug: true }
const config = dotenv.parse(buf, opt)
// expect a debug message because the buffer is not in KEY=VAL form
```

### Populate

The engine which populates the contents of your .env file to `process.env` is available for use. It accepts a target, a source, and options. This is useful for power users who want to supply their own objects.

For example, customizing the source:

```js
const dotenv = require('dotenv')
const parsed = { HELLO: 'world' }

dotenv.populate(process.env, parsed)

console.log(process.env.HELLO) // world
```

For example, customizing the source AND target:

```js
const dotenv = require('dotenv')
const parsed = { HELLO: 'universe' }
const target = { HELLO: 'world' } // empty object

dotenv.populate(target, parsed, { override: true, debug: true })

console.log(target) // { HELLO: 'universe' }
```

#### options

##### Debug

Default: `false`

Turn on logging to help debug why certain keys or values are not being populated as you expect.

##### override

Default: `false`

Override any environment variables that have already been set.

## ❓ FAQ

### Why is the `.env` file not loading my environment variables successfully?

Most likely your `.env` file is not in the correct place. [See this stack overflow](https://stackoverflow.com/questions/42335016/dotenv-file-is-not-loading-environment-variables).

Turn on debug mode and try again..

```js
require('dotenv').config({ debug: true })
```

You will receive a helpful error outputted to your console.

### Should I commit my `.env` file?

No. We **strongly** recommend against committing your `.env` file to version
control. It should only include environment-specific values such as database
passwords or API keys. Your production database should have a different
password than your development database.

### Should I have multiple `.env` files?

We recommend creating one `.env` file per environment. Use `.env` for local/development, `.env.production` for production and so on. This still follows the twelve factor principles as each is attributed individually to its own environment. Avoid custom set ups that work in inheritance somehow (`.env.production` inherits values form `.env` for example). It is better to duplicate values if necessary across each `.env.environment` file.

> In a twelve-factor app, env vars are granular controls, each fully orthogonal to other env vars. They are never grouped together as β€œenvironments”, but instead are independently managed for each deploy. This is a model that scales up smoothly as the app naturally expands into more deploys over its lifetime.
>
> – [The Twelve-Factor App](http://12factor.net/config)

### What rules does the parsing engine follow?

The parsing engine currently supports the following rules:

- `BASIC=basic` becomes `{BASIC: 'basic'}`
- empty lines are skipped
- lines beginning with `#` are treated as comments
- `#` marks the beginning of a comment (unless when the value is wrapped in quotes)
- empty values become empty strings (`EMPTY=` becomes `{EMPTY: ''}`)
- inner quotes are maintained (think JSON) (`JSON={"foo": "bar"}` becomes `{JSON:"{\"foo\": \"bar\"}"`)
- whitespace is removed from both ends of unquoted values (see more on [`trim`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String/Trim)) (`FOO=  some value  ` becomes `{FOO: 'some value'}`)
- single and double quoted values are escaped (`SINGLE_QUOTE='quoted'` becomes `{SINGLE_QUOTE: "quoted"}`)
- single and double quoted values maintain whitespace from both ends (`FOO="  some value  "` becomes `{FOO: '  some value  '}`)
- double quoted values expand new lines (`MULTILINE="new\nline"` becomes

```
{MULTILINE: 'new
line'}
```

- backticks are supported (`` BACKTICK_KEY=`This has 'single' and "double" quotes inside of it.` ``)

### What happens to environment variables that were already set?

By default, we will never modify any environment variables that have already been set. In particular, if there is a variable in your `.env` file which collides with one that already exists in your environment, then that variable will be skipped.

If instead, you want to override `process.env` use the `override` option.

```javascript
require('dotenv').config({ override: true })
```

### How come my environment variables are not showing up for React?

Your React code is run in Webpack, where the `fs` module or even the `process` global itself are not accessible out-of-the-box. `process.env` can only be injected through Webpack configuration.

If you are using [`react-scripts`](https://www.npmjs.com/package/react-scripts), which is distributed through [`create-react-app`](https://create-react-app.dev/), it has dotenv built in but with a quirk. Preface your environment variables with `REACT_APP_`. See [this stack overflow](https://stackoverflow.com/questions/42182577/is-it-possible-to-use-dotenv-in-a-react-project) for more details.

If you are using other frameworks (e.g. Next.js, Gatsby...), you need to consult their documentation for how to inject environment variables into the client.

### Can I customize/write plugins for dotenv?

Yes! `dotenv.config()` returns an object representing the parsed `.env` file. This gives you everything you need to continue setting values on `process.env`. For example:

```js
const dotenv = require('dotenv')
const variableExpansion = require('dotenv-expand')
const myEnv = dotenv.config()
variableExpansion(myEnv)
```

### How do I use dotenv with `import`?

Simply..

```javascript
// index.mjs (ESM)
import 'dotenv/config' // see https://github.com/motdotla/dotenv#how-do-i-use-dotenv-with-import
import express from 'express'
```

A little background..

> When you run a module containing an `import` declaration, the modules it imports are loaded first, then each module body is executed in a depth-first traversal of the dependency graph, avoiding cycles by skipping anything already executed.
>
> – [ES6 In Depth: Modules](https://hacks.mozilla.org/2015/08/es6-in-depth-modules/)

What does this mean in plain language? It means you would think the following would work but it won't.

`errorReporter.mjs`:
```js
import { Client } from 'best-error-reporting-service'

export default new Client(process.env.API_KEY)
```
`index.mjs`:
```js
// Note: this is INCORRECT and will not work
import * as dotenv from 'dotenv'
dotenv.config()

import errorReporter from './errorReporter.mjs'
errorReporter.report(new Error('documented example'))
```

`process.env.API_KEY` will be blank.

Instead, `index.mjs` should be written as..

```js
import 'dotenv/config'

import errorReporter from './errorReporter.mjs'
errorReporter.report(new Error('documented example'))
```

Does that make sense? It's a bit unintuitive, but it is how importing of ES6 modules work. Here is a [working example of this pitfall](https://github.com/dotenv-org/examples/tree/master/usage/dotenv-es6-import-pitfall).

There are two alternatives to this approach:

1. Preload dotenv: `node --require dotenv/config index.js` (_Note: you do not need to `import` dotenv with this approach_)
2. Create a separate file that will execute `config` first as outlined in [this comment on #133](https://github.com/motdotla/dotenv/issues/133#issuecomment-255298822)

### Why am I getting the error `Module not found: Error: Can't resolve 'crypto|os|path'`?

You are using dotenv on the front-end and have not included a polyfill. Webpack < 5 used to include these for you. Do the following:

```bash
npm install node-polyfill-webpack-plugin
```

Configure your `webpack.config.js` to something like the following.

```js
require('dotenv').config()

const path = require('path');
const webpack = require('webpack')

const NodePolyfillPlugin = require('node-polyfill-webpack-plugin')

module.exports = {
  mode: 'development',
  entry: './src/index.ts',
  output: {
    filename: 'bundle.js',
    path: path.resolve(__dirname, 'dist'),
  },
  plugins: [
    new NodePolyfillPlugin(),
    new webpack.DefinePlugin({
      'process.env': {
        HELLO: JSON.stringify(process.env.HELLO)
      }
    }),
  ]
};
```

Alternatively, just use [dotenv-webpack](https://github.com/mrsteele/dotenv-webpack) which does this and more behind the scenes for you.

### What about variable expansion?

Try [dotenv-expand](https://github.com/motdotla/dotenv-expand)

### What about syncing and securing .env files?

Use [dotenvx](https://github.com/dotenvx/dotenvx)

### What if I accidentally commit my `.env` file to code?

Remove it, [remove git history](https://docs.github.com/en/authentication/keeping-your-account-and-data-secure/removing-sensitive-data-from-a-repository) and then install the [git pre-commit hook](https://github.com/dotenvx/dotenvx#pre-commit) to prevent this from ever happening again. 

```
brew install dotenvx/brew/dotenvx
dotenvx precommit --install
```

### How can I prevent committing my `.env` file to a Docker build?

Use the [docker prebuild hook](https://dotenvx.com/docs/features/prebuild).

```bash
# Dockerfile
...
RUN curl -fsS https://dotenvx.sh/ | sh
...
RUN dotenvx prebuild
CMD ["dotenvx", "run", "--", "node", "index.js"]
```

## Contributing Guide

See [CONTRIBUTING.md](CONTRIBUTING.md)

## CHANGELOG

See [CHANGELOG.md](CHANGELOG.md)

## Who's using dotenv?

[These npm modules depend on it.](https://www.npmjs.com/browse/depended/dotenv)

Projects that expand it often use the [keyword "dotenv" on npm](https://www.npmjs.com/search?q=keywords:dotenv).