define-env

What is @nkzw/define-env?

process.env.* is not type-safe. It's easy to make a typo, or to forget setting an environment variable in a production environment. @nkzw/define-env is a tiny module that ensures all environment variables are defined on app startup, and provides a type-safe way to access them.

@nkzw/define-env saves time:

• Type-safe: Auto complete for environment variables. No more typos!
• Required Variables: All required environment variables must be present, otherwise the app will not start.
• Immutable environment variables: Environment variables are defined once on app startup, and cannot be changed during runtime.

Installation

npm install @nkzw/define-env

Usage

Create an env.tsx file in the root of your project listing all your env variables:

import defineEnv from '@nkzw/define-env';

export default defineEnv([
  'DISCORD_KEY',
  'PUSH_KEY',
  'STRIPE_SERVER_KEY',
  'WEB_PUSH_PUBLIC_KEY',
  …
]);

Now, your can access your env variables anywhere in your project using env('VARIABLE_NAME'):

import env from './env.tsx';

console.log(env('DISCORD_KEY'));

console.log(env('SUPER_SECRET_KEY')); // Type-error, because `SUPER_SECRET_KEY` is not defined in `env.tsx`.

You can also pass in your own object with environment variables:

export default defineEnv(['APPLE_KEY'], {
  APPLE_KEY: 'AppleBananaKey',
});