Load .env files and environment variables
Secure and friendly alternative to dotenv, using functional programming. With strong tests to prove its safety.
Follows the Twelve Factor App methodology.
Looking for the old envy
that reads JSON? See eliOcs/node-envy.
Contents
Why?
- Safest environment loader around.
- Validates file permissions are secure.
- Validates required env vars are defined.
- No side effects, does not modify
process.env
. - Returns property names in camelCase.
- Asserts that
.env
is ignored in git.
Have you spent a day rotating passwords because a developer accidentally pushed them to the repository? Yeah, that actually happens and it can cause chaos at companies. It doesn't matter if you delete the commit. Once it's out there, game over. People who are authorized to read the repository may not be authorized to have those credentials, including third party tools and services. If the repository is public, search engines may have crawled it. Consider everything to be compromised.
The envy
module helps you prevent that situation by providing a convenient mechanism for everyone to store credentials and other config locally and validate that it is correct without commiting them to the repository. It verifies that all relevant files have secure permissions and that the secrets file is explicitly ignored so that it cannot accidentally be commited.
Install
npm install envy --save
Usage
Get it into your program.
const envy = require('envy');
Load the environment variables.
const env = envy();
A .env.example
file is used as a template to determine which environment variables are required by your application. This file should be commited to your repository.
FOO=
A .env
file is used to provide the actual environment values. You should add this file to a local .gitignore
.
FOO=bar
Environment files look just like normal shell files (e.g. .bashrc
and friends). Values may be optionally wrapped in '
single quotes. This is recommended for shell compatibility, in case the value contains whitespace.
FOO=bar
SENTENCE='Hi, there!'
After assembling the environment from .env
and process.env
, it is filtered by a union of the properties in .env
and .env.example
. In other words, variables defined in either file will be returned and variables not defined in either file will be ignored. This is done to prevent surprising behavior, since process.env
often contains a wide variety of variables, some of which are implicitly set without the user's direct knowledge. It is better to be explicit about the variables you use, which improves safety and debugging.
API
envy(filepath)
Returns an object
with environment variables derived from process.env
and the contents at filepath
. If a variable is defined in both places, process.env
takes precedence so that users can easily override values on the command line. If all required variables are present in process.env
, then the .env
file need not exist. All property names are returned in camelcase.
filepath
Type: string
Default: .env
Path to the file where environment variables are kept. Must be hidden (start with a .
). Will also be used to compute the path of the example file (by appending .example
).
Tips
Mixing with command line options
Make a CLI with meow and use joi to further validate and parse the returned values.
const meow = require('meow');
const envy = require('envy');
const joi = require('joi');
const cli = meow();
const input = Object.assign({}, envy(), cli.flags);
const config = joi.attempt(input, {
port : joi.number().positive().integer().min(0).max(65535)
});
console.log('port:', config.port);
PORT=
PORT=1000
$ node cli.js
port: 1000
$ PORT=2000 node cli.js
port: 2000
$ node cli.js --port=3000
port: 3000
$ PORT=2000 node cli.js --port=3000
port: 3000
Modifying process.env
We recommend not using process.env
directly. But let's say you want to because a dependency expects you to set NODE_ENV
and you want to define it in .env
. No problem!
You should first ask the project to accept options as input so you don't need this.
const envy = require('envy');
const decamelize = require('decamelize');
const override = Object.entries(envy()).reduce((result, [key, val]) => {
result[decamelize(key).toUpperCase()] = val;
return result;
}, {});
Object.assign(process.env, override);
FAQ
Why not dotenv
or dotenv-safe
?
I see this as a successor to those projects. But envy
would not exist without them. dotenv
brought .env
files mainstream in Node.js projects. dotenv-safe
improved on it by introducing the .env.example
file. Now, envy
takes this even further by securing your files and returning an object with camelcase keys rather than modifying process.env
.
Resources
Related
- meow - Make command line apps
Contributing
See our contributing guidelines for more details.
- Fork it.
- Make a feature branch:
git checkout -b my-new-feature
- Commit your changes:
git commit -am 'Add some feature'
- Push to the branch:
git push origin my-new-feature
- Submit a pull request.
License
MPL-2.0 © Seth Holladay
Go make something, dang it.