Some NodeJS helpers

helpers.js

const isEmpty = require('lodash.isempty')
const isObject = require('lodash.isobject')

/**
 * Prevent empty object value
 *
 * @param {object} value
 * @returns {object|null}
 */
function notEmpty (value) {
  return (isObject(value) && isEmpty(value)) || typeof value === 'undefined' ? null : value
}

/**
 * Verify if a value is not an Array and return it as new array
 *
 * @param {string|number|object} value
 * @returns {array}
 */
function asArray (value = []) {
  return Array.isArray(value) ? value : [ value ]
}

/**
 * Verify an object value and return string value or an empty string
 *
 * @param {object} value
 * @returns {string}
 */
function asString (value = '') {
  return notEmpty(value) || ''
}

/**
 * Map a root object properties and return an array
 * If callback is not provided the functions returns [key, value]
 *
 * @param {object} obj
 * @returns {array}
 */
function mapObject (obj, callback = null) {
  const result = []
  const keys = Object.keys(obj)
  const len = keys.length

  for (let i = 0; i < len; i += 1) {
    const key = keys[i]
    const value = obj[key]
    let res = []

    if (callback) {
      res = callback(value, key)
    } else {
      res = [ key, value ]
    }

    if (res) result.push(res)
  }

  return result
}

module.exports = {
  notEmpty,
  asArray,
  asString,
  mapObject
}