var getJSON = function(url) {
return new Promise(function(resolve, reject) {
  var xhr = new XMLHttpRequest();
  xhr.open('get', url, true);
  xhr.responseType = 'json';
  xhr.onload = function() {
    var status = xhr.status;
    if (status == 200) {
      resolve(xhr.response);
    } else {
      reject(status);
    }
  };
  xhr.send();
});
};

setInterval(function() {
getJSON('http://www.lazada.com.my/ajax/lottery/spinTheWheel/?lang=en&platform=desktop&wheelToken=b5dd7e9dcbde84b3e11a9ae90d377b02&dpr=2').then(function(data) {
  if(data.data.voucherCode) {
  console.log('Voucher: ' + data.data.voucherCode);
alert('Voucher: ' + data.data.voucherCode);
  }
  else { console.log('no voucher'); }
  }, function(status) { //error detection....
alert('Something went wrong.');
}); }, 1000);