Function for GoogleSheets

// replace the previous signKey function with this one calling the CryptoJS Library instead of Google's libraries. 
// It assumes that you have added the CryptoJS library as a file in your google script project. 
// 


/* Encode with standard HMAC-SHA512 */
function signKey(url, secret) {
  var signature = CryptoJS.HmacSHA512(url, secret).toString();
  
  Logger.log(signature);
  
  return signature;
}