miconfig — Configuration loader for Node.js, browsers & Deno.

Features

• Easy: Designed for situations where a PhD into load configurations is infeasible.
• Lightweight: no bloat, less than 1KB with all dependencies.
• Isomorphic: Compatible with Node.js, browsers & Deno.
• Flexible: Super easy load any kind of configuration.
• Simple: The whole module is ~50 lines of code.

Install

$ npm install miconfig --save

Usage

In miconfig, a configuration is identified by environment name.

Load Configuration Files

Place the configuration files wherever you desire, e.g., in a folder called config:

.
├── index.js
└── config
   ├── default.js
   ├── production.js
   ├── staging.js
   └── test.js

Then, load them using miconfig:

const loadConfig = require('miconfig')

const FILES = [
  'default',
  NODE_ENV === 'development' ? undefined : NODE_ENV
].filter(Boolean)

const environment = FILES.reduce((acc, key) => {
  acc[key] = require(`./config/${key}`)
  return acc
}, {})

const config = loadConfig(environment)

In case you want to use a different file format (like YAML), you've to parser them before be loaded:

const environment = FILES.reduce((acc, key) => {
  acc[key] = fromYaml(`./config/${key}.yml`)
  return acc
}, {})

The default configuration is always loaded and merged with the target configuration environment.

miconfig uses process.env.NODE_ENV to determine what configuration should be loaded.

In case you want to use a different source of truth, you can pass it as second argument:

const loadConfig = require('miconfig')

const config = loadConfig(
  {
    default: require('./config/default'),
    production: require('./config/default')
  },
  process.env.APP_ENV
)

Accessing to configuration

After miconfig loads your configuration, you can safely access to any value.

Safe access

// read a value, don't care if it's empty
const database = config.get('database.url')

Safe access + default value

// read a value, use a default if empty
const database = config.get('database.url', 'localhost')

Require access

// read a value, throw an error if it doesn't exist
const database = config.require('database.url')

Typecheck access

// check if a value exists
if (config.has('feature.prerender')) {
  console.log('prerender is enabled')
}

Additionally, you can retrieve more than one value at one time with destructuring assignment:

Destructuring safe access

// read multiple values, don't care if it's empty
const { timezone, database } = config

Destructuring require access

// read multiple values, throw an error if one of them doesn't exist
const { timezone, database } = config.required

License

miconfig © Kiko Beats, released under the MIT License. Logo by Absurd Design.

Authored and maintained by Kiko Beats with help from contributors.

kikobeats.com · GitHub Kiko Beats · Twitter @Kikobeats