API POST

/* This function is used to receive JSON information through an apikey, nonce and then a hmac sha512 signed message with an apisecret is send through a JSON POST request */
function ImportJSONViaPost(url, payload, fetchOptions, query, parseOptions) {
  var postOptions = parseToObject_(fetchOptions);

  if (postOptions["method"] == null) {
    postOptions["method"] = "POST";
  }

  if (postOptions["payload"] == null) {
    postOptions["payload"] = payload;
  }

  if (postOptions["contentType"] == null) {
    postOptions["contentType"] = "application/x-www-form-urlencoded";
  }

  convertToBool_(postOptions, "validateHttpsCertificates");
  convertToBool_(postOptions, "useIntranet");
  convertToBool_(postOptions, "followRedirects");
  convertToBool_(postOptions, "muteHttpExceptions");

  return ImportJSONAdvanced(url, postOptions, query, parseOptions, includeXPath_, defaultTransform_);
}

function ImportJSONAdvanced(url, fetchOptions, query, parseOptions, includeFunc, transformFunc) {
  var jsondata = UrlFetchApp.fetch(url, fetchOptions);
  var object   = JSON.parse(jsondata.getContentText());

  return parseJSONObject_(object, query, parseOptions, includeFunc, transformFunc);
}