dotenv-flow-webpack

A Webpack plugin that allows you to securely use environment variables within your javascript web application, loading them using _dotenv-flow's_ .env* files loading strategy.

> _dotenv-flow_ extends _dotenv_, adding support of NODE_ENV-specific .env files _like .env.development, .env.test, .env.stage, and .env.production,_ and the appropriate .env.local overrides allowing your app to have multiple environments with selectively-adjusted environment variable setups and load them dynamically depending on the current NODE_ENV.

🌱 Inspired by _dotenv-webpack_, _CreateReactApp's storing configs in .env* files approach_,
the _Twelve-Factor App methodology_ in general, and _its store config in the environment section_ in particular.


Key Features

- Environment-based configuration: You can have different .env* files for various environments like _development_, _test_, and _production_.
- Variable overriding _(or environment-specific cascade)_: Allows you to selectively override the default and environment-specific variables with the appropriate .env*.local overrides.
- Secure: Injects variables by replacing the process.env. entries with the actual values from your .env* files during the build process, thus _exposing only those variables that are explicitly used in your code_.
- dotenv-flow as a Webpack plugin: directly integrates dotenv-flow with all its flexibility options to your build process making it easier to use environment variables without extra build scripts.

Installation

Using NPM:

``sh
$ npm install dotenv-flow-webpack --save-dev
`

Using Yarn:

`sh
$ yarn add dotenv-flow-webpack --dev
`

Basic usage

Here's how to include the dotenv-flow-webpack to your webpack.config.js:

`js
// webpack.config.js

const DotenvFlow = require('dotenv-flow-webpack');

module.exports = {
// ...other webpack configurations
plugins: [
new DotenvFlow({
// configuration options
})
],
// ...other webpack plugins
};
`

Configuration options

#### node_env
###### Type: string
###### Default: process.env.NODE_ENV || options.default_node_env

By default, the plugin refers the NODE_ENV environment variable to detect the environment to use.
With the node_env option you can force the module to use your custom environment value independent of process.env.NODE_ENV.

`js
new DotenvFlow({
node_env: 'production'
})
`

#### default_node_env
###### Type: string
###### Default: _undefined_

If the NODE_ENV environment variable is not set, the module doesn't load/parse any NODE_ENV-specific files at all.
Therefore, you may want to use "development" as the default environment.

`js
new DotenvFlow({
default_node_env: 'development'
})
`

#### path
###### Type: string
###### Default: process.cwd() _(current working directory)_

With the path initialization option you can specify a path to .env* files directory.

`js
new DotenvFlow({
path: './config'
})
`

If the option is not provided, the current working directory is used.

#### pattern
###### Type: string
###### Default: '.env[.node_env][.local]'

Allows you to change the default .env* files' naming convention
if you want to have a specific file naming structure for maintaining
your environment variables' files.

Default Value

The default value ".env[.node_env][.local]" makes dotenv-flow-webpack
look up and load the following files in order:

1. .env
2. .env.local
3. .env.${NODE_ENV}
4. .env.${NODE_ENV}.local

For example, when the proess.env.NODE_ENV (or options.node_env) is set to "development",
dotenv-flow-webpack will be looking for and parsing (if found) the following files:

1. .env
2. .env.local
3. .env.development
4. .env.development.local

Custom Pattern

Here is a couple of examples of customizing the .env* files naming convention:

For example, if you set the pattern to ".env/[local/]env[.node_env]",
dotenv-flow-webpack will look for these files instead:

1. .env/env
2. .env/local/env
3. .env/env.development
4. .env/local/env.development

… or if you set the pattern to ".env/[.node_env/].env[.node_env][.local]",
the plugin will try to find and parse:

1. .env/.env
2. .env/.env.local
3. .env/development/.env.development
4. .env/development/.env.development.local

› Please refer to dotenv-flow.listFiles(options) to learn more.

#### encoding
###### Type: string
###### Default: 'utf8'

You can specify the encoding of your files containing environment variables.

`js
new DotenvFlow({
encoding: 'base64'
})
`

#### system_vars
###### Type: boolean
###### Default: false

If true, all the predefined process.env.* variables will also be loaded.
In accordance to the dotenv-flow's specification, all the predefined system environment variables will have higher priority over the .env* files defined.

`js
new DotenvFlow({
system_vars: true
})
`

#### options.debug
###### Type: boolean
###### Default: false

Enables detailed logging to debug why certain variables are not being set as you expect.

`js
new DotenvFlow({
debug: true
})
`

#### silent
###### Type: boolean
###### Default: false

Set to true to suppress all kinds of errors and warnings.

`js
new DotenvFlow({
silent: true
})
`

Project Example

Let's suppose you have the following files in your project:

`sh


.env

DATABASE_HOST=127.0.0.1
DATABASE_PORT=27017
DATABASE_USER=default
DATABASE_PASS=
DATABASE_NAME=my_app

SERVICE_URL=/api/v1
`

`sh


.env.development

DATABASE_NAME=my_app_dev

SERVICE_URL=http://localhost:3000/api/v1
`

`sh


.env.test

SERVICE_URL=https://localhost:3001/api/v1
`

`sh


.env.production

DATABASE_HOST=10.0.0.32
DATABASE_PORT=27017
DATABASE_USER=devops
DATABASE_PASS=1qa2ws3ed4rf5tg6yh
DATABASE_NAME=application_storage

SERVICE_URL=https://myapp.com/api/v1
`

`js
// file1.js

if (process.env.NODE_ENV !== 'production') {
console.log(Running in the "${process.env.NODE_ENV}" mode.);
}
else {
console.log('We are in production!');
}

const USERS_ENDPOINT = process.env.SERVICE_URL + '/users';

console.log('USERS_ENDPOINT:', USERS_ENDPOINT);
`

Thus, when you build your app with NODE_ENV=development, the resulting bundle will include something like this:

`js
// file1.js

if (true) {
console.log("Running in the ".concat("development", " mode."));
} else {}

const USERS_ENDPOINT = "http://localhost:3000/api/v1" + '/users';

console.log('USERS_ENDPOINT:', USERS_ENDPOINT);
`

Or if you build your app with NODE_ENV=production, then the output will look like:

`js
// file1.js

if (false) {} else {
console.log('We are in production!');
}

const USERS_ENDPOINT = "https://myapp.com/api/v1" + '/users';

console.log('USERS_ENDPOINT:', USERS_ENDPOINT);
`

And after all the optimization procedures it will be compressed till:

`js
console.log("We are in production!");
console.log("USERS_ENDPOINT:", "https://myapp.com/api/v1/users");
`

Make a note that values of DATABASE_(HOST/PORT/USER/PASSWORD/NAME) will not be present in the resulting bundle while they are not referenced anywhere in the code.

Additional information

Please refer the dotenv-flow documentation to learn more about the .env* files concept.

Here is the list of related sections:

NODE_ENV-specific .env files
* Files under version control
* Variables overwriting/priority

Contributing

Feel free to dive in! Open an issue or submit PRs.

Running tests

Using NPM:

`sh
$ npm test
`

Using Yarn:

`sh
$ yarn test
``

License

Licensed under MIT © 2019-2023 Dan Kerimdzhanov