Jetpack_Subscriptions_Widget::fetch_subscriber_count PHP Method

    function fetch_subscriber_count()
    {
        $subs_count = get_transient('wpcom_subscribers_total');
        if (FALSE === $subs_count || 'failed' == $subs_count['status']) {
            Jetpack::load_xml_rpc_client();
            $xml = new Jetpack_IXR_Client(array('user_id' => JETPACK_MASTER_USER));
            $xml->query('jetpack.fetchSubscriberCount');
            if ($xml->isError()) {
                // if we get an error from .com, set the status to failed so that we will try again next time the data is requested
                $subs_count = array('status' => 'failed', 'code' => $xml->getErrorCode(), 'message' => $xml->getErrorMessage(), 'value' => isset($subs_count['value']) ? $subs_count['value'] : 0);
            } else {
                $subs_count = array('status' => 'success', 'value' => $xml->getResponse());
            }
            set_transient('wpcom_subscribers_total', $subs_count, 3600);
            // try to cache the result for at least 1 hour
        }
        return $subs_count;
    }