How to use

keys

function

in

Object

/**
  * Zmiana parametrów API w string
  * @param {Object} base
  * @param {Object} api parametry API
  */
  static parseApi(base, api) {
    let keys;
    _.assign(base, api);
    keys = _(base).omit(_.isUndefined).omit(_.isNull).keys();
    return _(keys).reduce((memo, key, index) => {
      return memo + key + ',' + base[key] + (index === keys.length - 1 ? '' : ',');
    }, '');
  }

http.createServer(function(req, res) {
 var cookies = _(parseCookies(req.headers.cookie))
  .keys()
  .map(function(key) {
   return key.toLowerCase();
  })
  .value()
  .sort();

 var headers = _.chain(req.headers)
  .omit('cookie')
  .keys()
  .map(function(key) {
   return key.toLowerCase();
  })
  .value()
  .sort();

 var body = JSON.stringify({
  headers: headers,
  cookies: cookies
 });

 // simulate server latency
 setTimeout(function() {
  res.writeHead(200, { 'Content-Type': 'application/json' });
  res.end(body);
 }, 500);
}).listen(1337, '0.0.0.0')