The simplest configuration module you will ever need

the-simplest-config-module.js

// This module will load ./process.env.APP_ENV.json and exports it
// And will also read args from command line and merge them, i.e.:
// node index.js --server.hostname=192.168.56.1
// will work.

// Usually this module should be in ./config/index.js
// And then you use var config = require('./config');

// You must set an APP_ENV
if (!process.env.APP_ENV) {
  throw new Error('You must specify an APP_ENV=environment variable');
}

var defaults = require('lodash').defaults;
var minimist = require('minimist');
var path = require('path');

var args = minimist(process.argv.slice(2));
var envConfig = require(path.join(__dirname, process.env.APP_ENV + '.json'));

module.exports = defaults(args, envConfig);