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

1$ 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:

1.
2├── index.js
3└── config
4   ├── default.js
5   ├── production.js
6   ├── staging.js
7   └── test.js

Then, load them using miconfig:

1const loadConfig = require('miconfig')
2
3const FILES = [
4  'default',
5  NODE_ENV === 'development' ? undefined : NODE_ENV
6].filter(Boolean)
7
8const environment = FILES.reduce((acc, key) => {
9  acc[key] = require(`./config/${key}`)
10  return acc
11}, {})
12
13const config = loadConfig(environment)

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

1const environment = FILES.reduce((acc, key) => {
2  acc[key] = fromYaml(`./config/${key}.yml`)
3  return acc
4}, {})

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:

1const loadConfig = require('miconfig')
2
3const config = loadConfig(
4  {
5    default: require('./config/default'),
6    production: require('./config/default')
7  },
8  process.env.APP_ENV
9)

Accessing to configuration

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

Safe access

1// read a value, don't care if it's empty
2const database = config.get('database.url')

Safe access + default value

1// read a value, use a default if empty
2const database = config.get('database.url', 'localhost')

Require access

1// read a value, throw an error if it doesn't exist
2const database = config.require('database.url')

Typecheck access

1// check if a value exists
2if (config.has('feature.prerender')) {
3  console.log('prerender is enabled')
4}

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

Destructuring safe access

1// read multiple values, don't care if it's empty
2const { timezone, database } = config

Destructuring require access

1// read multiple values, throw an error if one of them doesn't exist
2const { 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