Announcement 📣
From the makers that brought you Dotenv, introducing Dotenv Sync.
Sync your .env files between machines, environments, and team members.
Join the early access list.💛
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
Usage is easy!
# .env file
#
# Add environment-specific variables on new lines in the form of NAME=VALUE
#
DB_HOST=localhost
DB_USER=root
DB_PASS=s1mpl3
// index.js
require('dotenv').config()
console.log(process.env) // remove this after you've confirmed it working
.. or using ES6?
// index.mjs (ESM)
import 'dotenv/config' // see https://github.com/motdotla/dotenv#how-do-i-use-dotenv-with-import
import express from 'express'
process.env
now has the keys and values you defined in your .env
file.
require('dotenv').config()
...
const db = require('db')
db.connect({
host: process.env.DB_HOST,
username: process.env.DB_USER,
password: process.env.DB_PASS
})
See examples of using dotenv with various frameworks, languages, and configurations.
- nodejs
- nodejs (debug on)
- nodejs (override on)
- nodejs (multiline on)
- esm
- esm (preload)
- typescript
- typescript parse
- typescript config
- webpack
- webpack (plugin)
- react
- react (typescript)
- express
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 })
Default: false
Turn on multiline line break parsing.
require('dotenv').config({ multiline: true })
This allows specifying multiline values in this format:
PRIVATE_KEY="-----BEGIN PRIVATE KEY-----
MIGT...
7ure...
-----END PRIVATE KEY-----"
Ensure that the value begins with a single or double quote character, and it ends with the same character.
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
Default: false
Turn on multiline line break parsing.
require('dotenv').config({ multiline: true })
This allows specifying multiline values in this format:
PRIVATE_KEY="-----BEGIN PRIVATE KEY-----
MIGT...
7ure...
-----END PRIVATE KEY-----"
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. This is the preferred approach when using import
instead of require
.
$ 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
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.
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.
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 “environments”, 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'}
- empty lines are skipped
- lines beginning with
#
are treated as comments - whitespace followed by
#
marks the beginning of an inline 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
) (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'}
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 })
React has dotenv built in but with a quirk. Preface your environment variables with REACT_APP_
. See this stack overflow for more details.
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)
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
import dotenv from 'dotenv'
dotenv.config()
import errorReporter from './errorReporter.mjs'
errorReporter.report(new Error('documented example'))
process.env.API_KEY
will be blank.
Instead the above code should be written as..
// errorReporter.mjs
import { Client } from 'best-error-reporting-service'
export default new Client(process.env.API_KEY)
// index.mjs
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 also 2 alternatives to this approach:
- Preload dotenv:
node --require dotenv/config index.js
(Note: you do not need toimport
dotenv with this approach) - Create a separate file that will execute
config
first as outlined in this comment on #133
Try dotenv-expand
Try dotenv cli
See CONTRIBUTING.md
See CHANGELOG.md
These npm modules depend on it.
Projects that expand it often use the keyword "dotenv" on npm.