public function getConversationHistoryForApi($conversationId, $beforeMessageId)
 {
     $count = 10;
     $deletedTimestamp = $this->getConversationDeletedTimestamp($conversationId);
     $dtoList = $this->messageDao->findHistory($conversationId, $beforeMessageId, $count, $deletedTimestamp);
     $list = array();
     foreach ($dtoList as $message) {
         $list[] = $this->getMessageDataForApi($message);
     }
     $data = array('log' => $list);
     return $data;
 }