Reverse engineering PHP script to Google Appscript (Javascript)

I have a problem with reverse engineering a php script to work with google spreadsheet. First I will show you the original php code and then show you my solution. At this point I have no indication as to what is wrong with my code.

1 Original php code. Source: bittrex.com/Home/Api

$apikey='xxx';
$apisecret='xxx';
$nonce=time();
$uri='https://bittrex.com/api/v1.1/market/getopenorders?apikey='.$apikey.'&nonce='.$nonce;
$sign=hash_hmac('sha512',$uri,$apisecret);
$ch = curl_init($uri);
curl_setopt($ch, CURLOPT_HTTPHEADER, array('apisign:'.$sign));
$execResult = curl_exec($ch);
$obj = json_decode($execResult);

2 Reverse engineered google appscript code (just pure Javascript) of 1.

/* Generate Nonce */

function nonceGen() {
  var d = new Date();
  var timeStamp = d.getTime();
  return timeStamp;
}

/* Encode with standard HMAC-SHA512 */

function signKey(url, secret) {
var signature = Utilities.base64Encode(Utilities.computeHmacSignature(Utilities.MacAlgorithm.HMAC_SHA_512, url, secret));
  return signature;
}

function getBalances(apik, apis) {
  /* Set important variables */
  var url = 'https://bittrex.com/api/v1.1/account/getbalances';
  var inputapikey = '?apikey=';
  var inputnonce = '&nonce=';
  var nonce = nonceGen();

  /* Bring it all together */
  var uri = url.concat(inputapikey).concat(apik).concat(inputnonce).concat(nonce);

  /* Sign the message */
  var sign = signKey(uri,apis);

  /* Set apisign as header */
  var headers = { 'apisign' : sign };
  var options = { 'method' : 'get', 'headers' : headers };

  /* Retrieve response and parse the json into the data variable */
  var response = UrlFetchApp.fetch(uri, options);
  var data = JSON.parse(response.getContentText());

  /* Output on screen */
  Logger.log(data);  
 }

I can't seem to figure out what the problem is. There seems to be no output on the screen at all. Not even an error. Hopefully I can get some bugtesting suggestions.