Line data    Source code

       1             : /*
       2             :  * Copyright (c) 2014 Juniper Networks, Inc. All rights reserved.
       3             :  * Copyright Contributors to the OpenSDN project
       4             :  */
       5             : 
       6             : #ifndef _STAT_WALKER_H_
       7             : #define _STAT_WALKER_H_
       8             : 
       9             : #include <boost/function.hpp>
      10             : #include <string>
      11             : #include <map>
      12             : #include "db_handler.h"
      13             : 
      14             : /* This class provides a higher-level interface for DbHandler's StatTableInsert
      15             :  * It allows for nested stat strutures
      16             :  * The client calls "Push" to fill in a child node
      17             :  * The client calls "Pop" when the current node has no more children to fill
      18             :  * 
      19             :  * This class will call StatTableInsert with the right tags and attribs when 
      20             :  * "Pop" is called.
      21             :  */
      22             : class StatWalker {
      23             : public:
      24             :     typedef boost::function<void(
      25             :         const uint64_t& timestamp,
      26             :         const std::string& statName,
      27             :         const std::string& statAttr,
      28             :         const DbHandler::TagMap & attribs_tag,
      29             :         const DbHandler::AttribMap & attribs)> StatTableInsertFn ;
      30             : 
      31             :     struct TagVal {
      32             :         std::pair<std::string,DbHandler::Var> prefix;
      33             :         DbHandler::Var val;
      34             :     };
      35             :     typedef std::map<std::string,TagVal> TagMap;
      36             : 
      37             :     // Record a new child node
      38             :     //     name : local name of this node attribute in the parent struct
      39             :     //     tags : tags at this level. These tags will be inherited by children
      40             :     //     attribs : attribs at this level.  
      41             :     void Push(const std::string& name,
      42             :         const TagMap& tags,
      43             :         const DbHandler::AttribMap& attribs);
      44             : 
      45             :     // The current node's children have been completely processed.
      46             :     // Its time to call StatTableInsert
      47             :     void Pop(void);
      48             : 
      49           3 :     StatWalker(StatTableInsertFn fn, const uint64_t &timestamp,
      50           3 :                const std::string& statName, const TagMap& tags) :
      51           3 :             timestamp_(timestamp),
      52           3 :             stat_name_(statName),
      53           3 :             fn_(fn),
      54           3 :             top_tags_(tags)  {}
      55             :     ~StatWalker();
      56             : private:
      57             :     struct StatNode {
      58             :         std::string name;
      59             :         TagMap tags;
      60             :         DbHandler::AttribMap attribs;
      61             :     };
      62             : 
      63             :     // Utility function for aggregating StatWalker::TagMap into DbHandler::TagMap
      64             :     static void FillTag(DbHandler::TagMap *attribs_tag,
      65             :         const std::pair<const std::string, TagVal>* tag);
      66             : 
      67             :     const uint64_t timestamp_;
      68             :     const std::string stat_name_;
      69             :     const StatTableInsertFn fn_;
      70             :     const TagMap top_tags_;
      71             :     std::vector<StatNode> nodes_;
      72             : };
      73             : 
      74             : #endif
      75             :