private function deleteNode($db_node_whole, $main_buss_id, $idc, $op_user, $zk_web, $del_flags)
 {
     $node = NodeServ::getNodeByNodeWhole($db_node_whole, $main_buss_id);
     if ($node === FALSE) {
         return InfoDescUtil::ERR_NODE_NOT_EXIST;
     }
     $db_node_type = $node["node_type_code"];
     $sub_buss_id = $node["sub_buss_id"];
     // 1. check whether current node has sub nodes
     $qconf_node_path = PathUtil::getQconfPath($db_node_whole);
     $children = -1;
     $retry_time = 0;
     while ($children === -1 && $retry_time <= InfoDescUtil::ZK_MAX_RETRY_TIME) {
         QconfMgrLog::err(__FILE__, __LINE__, "retry {$retry_time} of " . InfoDescUtil::ZK_MAX_RETRY_TIME . " to get children of {$db_node_whole} on {$idc}");
         $children = $zk_web->get_children($qconf_node_path);
         $retry_time++;
     }
     if ($children === -1) {
         QconfMgrLog::err(__FILE__, __LINE__, "Failed to get children of {$db_node_whole} on {$idc}");
         return InfoDescUtil::ERR_ZOOKEEPER_FAIL;
     }
     // 2. delete children nodes or services if needed
     if (count($children) > 0) {
         if ($del_flags === InfoDescUtil::DELETE_TYPE_WHOLE) {
             if ($db_node_type === InfoDescUtil::NODE_TYPE_SERV_FATHER) {
                 $clear_ret = ServiceController::clearServiceWithLink($zk_web, $db_node_whole, $idc, $main_buss_id, $sub_buss_id, $op_user);
                 if ($clear_ret != InfoDescUtil::QCONF_OK) {
                     QconfMgrLog::err(__FILE__, __LINE__, "Failed to clear services of {$db_node_whole} on {$idc}");
                     return $clear_ret;
                 }
             } else {
                 // delete include children
                 foreach ($children as $child) {
                     $child_node_whole = PathUtil::unionPath($db_node_whole, $child);
                     $del_ret = self::deleteNode($child_node_whole, $main_buss_id, $idc, $op_user, $zk_web, InfoDescUtil::DELETE_TYPE_WHOLE);
                     if ($del_ret != InfoDescUtil::QCONF_OK) {
                         QconfMgrLog::err(__FILE__, __LINE__, "Failed to delete children of {$db_node_whole} on {$idc}");
                         return $del_ret;
                     }
                 }
             }
         } else {
             // delete only self
             QconfMgrLog::err(__FILE__, __LINE__, "Exist children nodes of {$db_node_whole} on {$idc}");
             return InfoDescUtil::ERR_SUB_NODE_NOT_NULL;
         }
     }
     // 3. delete conf from zookeeper
     if ($db_node_type === InfoDescUtil::NODE_TYPE_SERV_FATHER) {
         $ret = -1;
         $retry_time = 0;
         while ($ret === -1 && $retry_time <= InfoDescUtil::ZK_MAX_RETRY_TIME) {
             QconfMgrLog::err(__FILE__, __LINE__, "retry {$retry_time} of " . InfoDescUtil::ZK_MAX_RETRY_TIME . " to delete group path for {$db_node_whole} on {$idc}");
             $ret = $zk_web->delete_group_path($qconf_node_path);
             $retry_time++;
         }
     } else {
         $ret = -1;
         $retry_time = 0;
         while ($ret === -1 && $retry_time <= InfoDescUtil::ZK_MAX_RETRY_TIME) {
             QconfMgrLog::err(__FILE__, __LINE__, "retry {$retry_time} of " . InfoDescUtil::ZK_MAX_RETRY_TIME . " to delete {$db_node_whole} on {$idc}");
             $ret = $zk_web->delete_conf($qconf_node_path);
             $retry_time++;
         }
     }
     if ($ret === -1) {
         OpServ::insert(InfoDescUtil::OP_TYPE_DEL, $db_node_whole, $idc, InfoDescUtil::OP_STATUS_ZOO_FAILED, $main_buss_id, $sub_buss_id, $op_user, "");
         return InfoDescUtil::ERR_ZOOKEEPER_FAIL;
     }
     // 4. delete in mysql
     $ret = NodeServ::delNodeByIdc($node["node_id"], $idc);
     if ($ret === TRUE && $node["node_level"] == 1) {
         $ret = PermServ::delPermByIdc(trim($db_node_whole, "\\/"), $main_buss_id, $idc);
         if ($ret === TRUE) {
             // notify admins
             AdminConf::notifyAdmin("Delete root node " . $db_node_whole . " for {$op_user} on {$idc}", $op_user, FALSE);
         }
     }
     if ($ret === -1) {
         OpServ::insert(InfoDescUtil::OP_TYPE_DEL, $db_node_whole, $idc, InfoDescUtil::OP_STATUS_MYSQL_FAILED, $main_buss_id, $sub_buss_id, $op_user, "");
         QconfMgrLog::err(__FILE__, __LINE__, "failed to delete {$db_node_whole} from {$idc} in mysql");
         return InfoDescUtil::ERR_MYSQL_FAIL;
     }
     // 6. delete the feedback items
     $fd_res = FeedbackServ::deleteFeedbackByNode($qconf_node_path, $idc);
     if ($fd_res === FALSE) {
         QconfMgrLog::err(__FILE__, __LINE__, "failed to delete feedbacks of qconf_node_path({$qconf_node_path}), idc({$idc})");
     } else {
         $update_time = date('Y-m-d H:i:s', time());
         $fd_op_res = FeedbackOpServ::recordOp(InfoDescUtil::OP_TYPE_FEEDBACK_DELETE_BY_NODE, "", $qconf_node_path, $idc, "", "", $update_time);
         if ($fd_op_res === FALSE) {
             QconfMgrLog::err(__FILE__, __LINE__, "failed to add feedback operation of qconf_node_path({$qconf_node_path}), idc({$idc})");
         }
     }
     // 7. delete normal user permision
     if (trim($node["idc"], ",") === $idc) {
         // last idc of the node has been deleted
         $delete_res = UserPermServ::deleteNormalByDeleteOp($db_node_whole);
         if ($delete_res === FALSE) {
             QconfMgrLog::err(__FILE__, __LINE__, "failed to delete user perm items on db_node_whole({$db_node_whole})");
             OpServ::insert(InfoDescUtil::OP_TYPE_USER_PERM_NORMAL_DELETE, $db_node_whole, $idc, InfoDescUtil::OP_STATUS_MYSQL_FAILED, $main_buss_id, $sub_buss_id, $op_user, "delete all user perm on {$db_node_whole} failed");
         } else {
             QconfMgrLog::err(__FILE__, __LINE__, "delete all normal perm items on db_node_whole({$db_node_whole})");
             OpServ::insert(InfoDescUtil::OP_TYPE_USER_PERM_NORMAL_DELETE, $db_node_whole, $idc, InfoDescUtil::OP_STATUS_SUCCESS, $main_buss_id, $sub_buss_id, $op_user, "delete all user perm on {$db_node_whole} success");
         }
     }
     OpServ::insert(InfoDescUtil::OP_TYPE_DEL, $db_node_whole, $idc, InfoDescUtil::OP_STATUS_SUCCESS, $main_buss_id, $sub_buss_id, $op_user, "");
     return InfoDescUtil::QCONF_OK;
 }