Serialize an Object into URI Query in Javascript

serialize_query.js

/**
 * This method converts a Javascript object into
 * a URI query string. Also handles nested arrays
 * and objects (in Rails / PHP syntax)
 *
 * @author  Sheharyar Naseer (@sheharyarn)
 * @license MIT
 *
 * @example
 *
 * let params = {
 *   a: 100,
 *   b: 'has spaces',
 *   c: [1, 2, 3],
 *   d: { x: 9, y: 8}
 * }
 *
 * serializeQuery(params)
 * // returns 'a=100&b=has%20spaces&c[]=1&c[]=2&c[]=3&d[x]=9&d[y]=8
 *
 **/

function serializeQuery(params, prefix) {
  const query = Object.keys(params).map((key) => {
    const value  = params[key];

    if (params.constructor === Array)
      key = `${prefix}[]`;
    else if (params.constructor === Object)
      key = (prefix ? `${prefix}[${key}]` : key);

    if (typeof value === 'object')
      return serializeParams(value, key);
    else
      return `${key}=${encodeURIComponent(value)}`;
  });

  return [].concat.apply([], query).join('&');
}