/** called before any actions **/
 public function onBefore()
 {
     global $MONGO;
     //exception handler
     set_exception_handler(array($this, "exceptionHandler"));
     $this->_admin = MUser::userInSession();
     if (!$this->_admin) {
         //if user is loged in?
         $server = MServer::serverWithIndex(xi("host"));
         //filter server plugins
         if (class_exists("RFilter")) {
             RFilter::apply("SERVER_FILTER", $server);
         }
         //if auth is disabled
         if ($server && !$server->mongoAuth() && !$server->controlAuth()) {
             MUser::login("rockmongo_memo", "rockmongo_memo", xi("host"), "admin", 10800);
             $this->_admin = MUser::userInSession();
         } else {
             $this->redirect("login.index", array("host" => xi("host")));
         }
     }
     if (!$this->_admin->validate()) {
         $this->redirect("login.index", array("host" => $this->_admin->hostIndex()));
     }
     $this->_server = MServer::serverWithIndex($this->_admin->hostIndex());
     $this->_mongo = $this->_server->mongo();
     //log query
     if (isset($MONGO["features"]["log_query"]) && $MONGO["features"]["log_query"] == "on") {
         $this->_logQuery = true;
     }
     //render header
     if (!$this->isAjax()) {
         render_view("header");
     }
 }