confit/lib/common.js

Environment-aware configuration.

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 │  Copyright (C) 2016 PayPal                                                 │
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'use strict';

const Path = require('path');

/**
 * Returns `true` if the given object is strictly an `Object` and not a `Function` (even though functions are objects in JavaScript). Otherwise, returns `false`
 * @param {unknown} val
 * @returns {boolean}
 */
const isObject = (value) => value !== null && typeof value === "object";


module.exports = {

    env: {
        development: /^dev/i,
        test       : /^test/i,
        staging    : /^stag/i,
        production : /^prod/i
    },

    isAbsolute(path) {
        if (typeof path === 'string') {
            path = Path.normalize(path);
            return path === Path.resolve(path);
        }
        return false;
    },

    merge(src, dest) {
        // NOTE: Do not merge arrays and only merge objects into objects. Do not merge special objects created from custom Classes.
        if (!Array.isArray(src) && isObject(src) && isObject(dest) && Object.getPrototypeOf(src) ===  Object.prototype) {
            for (let prop of Object.getOwnPropertyNames(src)) {
                let descriptor = Object.getOwnPropertyDescriptor(src, prop);
                descriptor.value = this.merge(descriptor.value, dest[prop]);
                Object.defineProperty(dest, prop, descriptor);
            }
            return dest;
        }

        return src;
    }

};