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dotenv-expand 

Dotenv-expand adds variable expansion on top of dotenv. If you find yourself needing to expand environment variables already existing on your machine, then dotenv-expand is your tool.


Install

``bash


Install locally (recommended)

Or installing with yarn? yarn add dotenv-expand

Usage

Create a .env file in the root of your project:

`dosini
PASSWORD="s1mpl3"
DB_PASS=$PASSWORD
`

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

`javascript
const dotenv = require('dotenv')
const dotenvExpand = require('dotenv-expand')

dotenvExpand.expand(dotenv.config())

console.log(process.env) // remove this after you've confirmed it is expanding
`

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

`
dotenvExpand.expand(dotenv.config())

...

connectdb(process.env.DB_PASS)
`

$3

> Note: Consider using 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), has built-in expansion support, adds better debugging, and works with ANY language, framework, or platform. – motdotla

You can use the --require (-r) command line option to preload dotenv & dotenv-expand. By doing this, you do not need to require and load dotenv or dotenv-expand in your application code. This is the preferred approach when using import instead of require.

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

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

`bash
$ node -r dotenv-expand/config your_script.js dotenv_config_path=/custom/path/to/your/env/vars
`

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

`bash
$ DOTENV_CONFIG_=value node -r dotenv-expand/config your_script.js
`

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

Examples

See tests/.env.test for simple and complex examples of variable expansion in your .env
file.

Documentation

dotenv-expand exposes one function:

* expand

$3

expand will expand your environment variables.

`js
const env = {
parsed: {
BASIC: 'basic',
BASIC_EXPAND: '${BASIC}',
BASIC_EXPAND_SIMPLE: '$BASIC'
}
}

console.log(dotenvExpand.expand(env))
`

#### Options

##### processEnv

Default: process.env

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

`js
const myEnv = {}
const env = {
processEnv: myEnv,
parsed: {
HELLO: 'World'
}
}
dotenvExpand.expand(env)

console.log(myEnv.HELLO) // World
console.log(process.env.HELLO) // undefined
`

FAQ

$3

See a full list of rules here.

$3

As of v12.0.0 dotenv-expand no longer expands process.env.

If you need this ability, use dotenvx by shipping an encrypted .env file with your code - allowing safe expansion at runtime.

$3

Use dotenvx as dotenv-expand does not support this.

dotenv-expand is a separate module (without knowledge of the loading of process.env and the .env` file) and so cannot reliably know what to override.

Contributing Guide

See CONTRIBUTING.md

CHANGELOG

See CHANGELOG.md

Who's using dotenv-expand?

These npm modules depend on it.