/**
* Call the query method on the authenticated client.
*
* @param DateTime $startDate
* @param DateTime $endDate
* @param string $metrics
* @param array $others
*
* @return mixed
*/
public function performQuery(DateTime $startDate, DateTime $endDate, $metrics, $others = array())
{
return $this->client->performQuery($this->siteId, $startDate->format('Y-m-d'), $endDate->format('Y-m-d'), $metrics, $others);
}