$ npm install dotenv
Dotenv is supported by the community.
Special thanks to:Dotenv is a zero-dependency module that loads environment variables from a .env
file into process.env
. Storing configuration in the environment separate from code is based on The Twelve-Factor App methodology.
# install locally (recommended)
npm install dotenv --save
Or installing with yarn? yarn add dotenv
Create a .env
file in the root of your project:
S3_BUCKET="YOURS3BUCKET"
SECRET_KEY="YOURSECRETKEYGOESHERE"
As early as possible in your application, import and configure dotenv:
require('dotenv').config()
console.log(process.env) // remove this after you've confirmed it is working
import 'dotenv/config'
That's it. process.env
now has the keys and values you defined in your .env
file:
require('dotenv').config()
...
s3.getBucketCors({Bucket: process.env.S3_BUCKET}, function(err, data) {})
If you need multiline variables, for example private keys, those are now supported (>= v15.0.0
) with line breaks:
PRIVATE_KEY="-----BEGIN RSA PRIVATE KEY-----
...
Kh9NV...
...
-----END RSA PRIVATE KEY-----"
Alternatively, you can double quote strings and use the \n
character:
PRIVATE_KEY="-----BEGIN RSA PRIVATE KEY-----\nKh9NV...\n-----END RSA PRIVATE KEY-----\n"
Comments may be added to your file on their own line or inline:
# 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.
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.
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' }
You can use the --require
(-r
) command line option to preload dotenv. By doing this, you do not need to require and load dotenv in your application code.
$ node -r dotenv/config your_script.js
The configuration options below are supported as command line arguments in the format dotenv_config_<option>=value
$ 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.
$ DOTENV_CONFIG_<OPTION>=value node -r dotenv/config your_script.js
$ DOTENV_CONFIG_ENCODING=latin1 DOTENV_CONFIG_DEBUG=true node -r dotenv/config your_script.js dotenv_config_path=/custom/path/to/.env
You need to add the value of another variable in one of your variables? Use dotenv-expand.
You need to keep .env
files in sync between machines, environments, or team members? Use dotenv-vault.
Note: Currently released as RC Candidate dotenv@16.1.0-rc1
Encrypt your environment variables by doing:
npx dotenv-vault local build
This will create an encrypted .env.vault
file along with a .env.keys
file containing the encryption keys. Set the DOTENV_KEY
environment variable by copying and pasting the key value from the .env.keys
file onto your server or cloud provider. For example in heroku:
heroku config:set DOTENV_KEY=<key string from .env.keys>
Commit your .env.vault file safely to code and deploy. Your .env.vault fill be decrypted on boot, its environment variables injected, and your app work as expected.
You have two options for managing multiple environments - locally managed or vault managed - both use dotenv-vault.
Locally managed never makes a remote API call. It is completely managed on your machine. Vault managed adds conveniences like backing up your .env file, secure sharing across your team, access permissions, and version history. Choose what works best for you.
Create a .env.production
file in the root of your project and put your production values there.
# .env.production
S3_BUCKET="PRODUCTION_S3BUCKET"
SECRET_KEY="PRODUCTION_SECRETKEYGOESHERE"
Rebuild your .env.vault
file.
$ npx dotenv-vault local build
Check your .env.keys
file. There is a production DOTENV_KEY
that coincides with the additional DOTENV_VAULT_PRODUCTION
cipher in your .env.vault
file.
Set the production DOTENV_KEY
on your server, recommit your .env.vault
file to code, and deploy. That's it!
Sync your .env file. Run the push command and follow the instructions. learn more
$ npx dotenv-vault push
Manage multiple environments with the included UI. learn more
$ npx dotenv-vault open
Build your .env.vault
file with multiple environments.
$ npx dotenv-vault build
Access your DOTENV_KEY
.
$ npx dotenv-vault keys
Set the production DOTENV_KEY
on your server, recommit your .env.vault
file to code, and deploy. That's it!
See examples of using dotenv with various frameworks, languages, and configurations.
Dotenv exposes two functions:
config
parse
config
will read your .env
file, parse the contents, assign it to
process.env
,
and return an Object with a parsed
key containing the loaded content or an error
key if it failed.
const result = dotenv.config()
if (result.error) {
throw result.error
}
console.log(result.parsed)
You can additionally, pass options to config
.
Default: path.resolve(process.cwd(), '.env')
Specify a custom path if your file containing environment variables is located elsewhere.
require('dotenv').config({ path: '/custom/path/to/.env' })
Default: utf8
Specify the encoding of your file containing environment variables.
require('dotenv').config({ encoding: 'latin1' })
Default: false
Turn on logging to help debug why certain keys or values are not being set as you expect.
require('dotenv').config({ debug: process.env.DEBUG })
Default: false
Override any environment variables that have already been set on your machine with values from your .env file.
require('dotenv').config({ override: true })
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.
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' }
Default: false
Turn on logging to help debug why certain keys or values are not being set as you expect.
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
.env
file not loading my environment variables successfully?Most likely your .env
file is not in the correct place. See this stack overflow.
Turn on debug mode and try again..
require('dotenv').config({ debug: true })
You will receive a helpful error outputted to your console.
.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.
.env
files?No. We strongly recommend against having a "main" .env
file and an "environment" .env
file like .env.test
. Your config should vary between deploys, and you should not be sharing values between environments.
In a twelve-factor app, env vars are granular controls, each fully orthogonal to other env vars. They are never grouped together as βenvironmentsβ, 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 parsing engine currently supports the following rules:
BASIC=basic
becomes {BASIC: 'basic'}
#
are treated as comments#
marks the beginning of a comment (unless when the value is wrapped in quotes)EMPTY=
becomes {EMPTY: ''}
)JSON={"foo": "bar"}
becomes {JSON:"{\"foo\": \"bar\"}"
)trim
) (FOO= some value
becomes {FOO: 'some value'}
)SINGLE_QUOTE='quoted'
becomes {SINGLE_QUOTE: "quoted"}
)FOO=" some value "
becomes {FOO: ' some value '}
)MULTILINE="new\nline"
becomes{MULTILINE: 'new
line'}
BACKTICK_KEY=`This has 'single' and "double" quotes inside of it.`
)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.
require('dotenv').config({ override: true })
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
, which is distributed through create-react-app
, it has dotenv built in but with a quirk. Preface your environment variables with REACT_APP_
. See this stack overflow 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.
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:
const dotenv = require('dotenv')
const variableExpansion = require('dotenv-expand')
const myEnv = dotenv.config()
variableExpansion(myEnv)
import
?Simply..
// 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.
What does this mean in plain language? It means you would think the following would work but it won't.
errorReporter.mjs
:
import { Client } from 'best-error-reporting-service'
export default new Client(process.env.API_KEY)
index.mjs
:
// 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..
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.
There are two alternatives to this approach:
node --require dotenv/config index.js
(Note: you do not need to import
dotenv with this approach)config
first as outlined in this comment on #133Try dotenv-expand
Use dotenv-vault
See CONTRIBUTING.md
See CHANGELOG.md
These npm modules depend on it.
Projects that expand it often use the keyword "dotenv" on npm.
© 2010 - cnpmjs.org x YWFE | Home | YWFE