With capulet, you parse a configuration object from an array of required fields followed by any number of object sources.

If any key is missing after merging the object sources, capulet will throw. If you want a key to be optional, you should supply a default value object somewhere in the chain (that value can be undefined or null).

The new config object is populated by merging in objects left to right (like Object.assign or _.merge). Any defaults should be added first, and then the user configuration source.

const capulet = require('capulet');

const config = capulet([
	'db',
	'templateDirectory',
], {
	'db': 'mongodb://localhost:27017/mydb',
}, process.env);

const db = config.get('db');

The config exposes a middleware function for use with connect/express, that exposes the get method as config on the request object.

const express = require('express');
const app = express();

app.use(config.middleware());

app.use(function (req, res) {
	const db = req.config('db');
	const entireConfig = req.config();
});