public static function getHost()
    {
        $host = null;
        if (isset($_SERVER['HTTP_X_FORWARDED_HOST'])) {
            $host = $_SERVER['HTTP_X_FORWARDED_HOST'];
        } elseif (isset($_SERVER['HTTP_HOST'])) {
            $host = $_SERVER['HTTP_HOST'];
        } elseif (isset($_SERVER['SERVER_NAME'])) {
            $host = $_SERVER['SERVER_NAME'];
        } else {
            $host = gethostname();
        }
        return $host;
    }