MySQL - MySQL++在c++11环境下接口设计

安装官方提供的mysqlconnect后，可以使用mysql++库，在官方的C API上再次做一个c++面向对象封装。

这里mysql++的安装依赖于mysql-connector-c。安装参考：http://dev.mysql.com/doc/connector-c/en/connector-c-installation-source-unix.html

c++11下注意：

1.由于mysql++并没有采用c++11，所以在使用的时候报了一些警告，需要对源码进行修改。

2.在获取字段类型的API在g++编译器下不是非常理想

3.执行sql存在错误时，系统会coredump，注意try语句的使用

下面部分代码：

 #pragma once
 #include "mysql++.h"

 #define MYSQL_CFG_FILE "..//..//common//MySQL//config.json"

 typedef struct mysql_config
 {
     std::string ip;
     int port;
     std::string user;
     std::string passwd;
     std::string database_name;
 }mysql_cfg;

 typedef struct mysql_field_information
 {
     std::string Field;
     std::string Type;
     std::string Null;
     std::string Key;
     std::string Default;
     std::string Extra;
 }mysql_field_info;

 typedef std::vector<mysql_field_info> mysql_table_info;

 typedef struct mysql_field_data
 {

     short SHORT;
     int INTEGER;
     long long BIGINT;
     float FLOAT;
     double DOUBLE;

     std::string DATETIME;

     std::string VARCHAR;
 }mysql_field;

 typedef std::map<std::string, std::vector<mysql_field>> mysql_table; 

 enum mysql_database_info
 {
     SHOW_VERISON,
     SHOW_DATABASES,
     SHOW_TABLES
 };

 class DMMySQL
 {
 public:
     DMMySQL();
     ~DMMySQL();

     void show_databases_info(int flag, std::vector<std::string>& databases);

     bool get_table_desc(std::string table_name, mysql_table_info& table_info);

     bool insert_mysql(std::string sql);

     bool insert_mysql(std::string table_name, std::map<std::string, std::string>& insert_data);

     bool update_mysql(std::string sql);

     bool update_mysql(std::string table_name, std::string field_name, std::string field_value,
         std::string filter_key, std::string filter_value);

     bool select_mysql(std::string table_name, mysql_table& table_data);

     bool select_mysql(std::string table_name, std::string field_name, std::vector<mysql_field>& field_data);

     bool select_mysql(std::string table_name, std::string field_name,
         std::string filter_key, std::string filter_value,
         std::vector<mysql_field>& field_data, std::string filter_opt = "=");

 private:
     bool load_mysql_config();

     void init();

     bool conncet_mysql();

     void disconnect_mysql();

     void trans_data_type(std::string input_data, std::string data_type, mysql_field& field_data);

 private:
     mysql_cfg _mysql_cfg;
     mysqlpp::Connection _conn;
 };

 #include "json/json.h"
 #include <fstream>
 #include <ace/Log_Msg.h>
 #include "DMMySQL.h"
 #include <cxxabi.h>

 #define TRY_SQL \
     try{

 #define CATCH_SQL_ERROR \
 }\
 catch(const mysqlpp::BadQuery& error)\
 {\
     ACE_DEBUG((LM_ERROR,"MySQL Query error:%s!\n",error.what()));\
     return false;\
 }\
 catch (const mysqlpp::BadConversion& error)\
 {\
     ACE_DEBUG((LM_ERROR,"MySQL Conversion error:%s!\n",error.what()));\
     return false;\
 }\
 catch (const mysqlpp::Exception& error)\
 {\
     ACE_DEBUG((LM_ERROR,"MySQL Exception error:%s!\n",error.what()));\
     return false;\
 }

 DMMySQL::DMMySQL()
 {
     init();
 }

 DMMySQL::~DMMySQL()
 {
     disconnect_mysql();
 }

 bool DMMySQL::load_mysql_config()
 {
     std::ifstream cfg_file;
     cfg_file.open(MYSQL_CFG_FILE, std::ios::binary);

     if (!cfg_file.is_open())
     {
         return ;
     }

     Json::Reader Reader;
     Json::Value Root;

     if (Reader.parse(cfg_file,Root))
     {
         _mysql_cfg.ip = Root["mysql_ip"].asString();
         _mysql_cfg.port = Root["mysql_port"].asInt();
         _mysql_cfg.user = Root["mysql_user"].asString();
         _mysql_cfg.passwd = Root["mysql_passwd"].asString();
         _mysql_cfg.database_name = Root["database_name"].asString();
     }
     else
     {
         ACE_DEBUG((LM_ERROR,"parse mysql config file failure!\n"));
         return false;
     }

     return true;
 }

 void DMMySQL::init()
 {
     if (load_mysql_config())
     {
         conncet_mysql();
     }
 }

 bool DMMySQL::conncet_mysql()
 {
     if (!_conn.connect(_mysql_cfg.database_name.c_str(), _mysql_cfg.ip.c_str(),
         _mysql_cfg.user.c_str(), _mysql_cfg.passwd.c_str(), _mysql_cfg.port))
     {
         ACE_DEBUG((LM_ERROR,"connect MySQL database failure!\n"));
         return false;
     }

     return true;
 }

 void DMMySQL::show_databases_info(int flag, std::vector<std::string>& databases)
 {
     std::string opration;    

     switch (flag)
     {
     case SHOW_VERISON:
         {
             std::string version_info = _conn.client_version();
             databases.push_back(version_info);
             return;
         }
     case SHOW_DATABASES:
         {
             opration = "show databases";
             break;
         }
     case SHOW_TABLES:
         {

             opration = "show tables";
             break;
         }
     default:
         {
             return;
         }
     }

     mysqlpp::Query query = _conn.query(opration);
     if (mysqlpp::StoreQueryResult res = query.store())
     {
         mysqlpp::StoreQueryResult::iterator rit;
         for (rit = res.begin(); rit != res.end(); ++rit)
         {
             databases.push_back((*rit)[].c_str());
         }
     }
 }

 bool DMMySQL::get_table_desc(std::string table_name, mysql_table_info& tbl_info)
 {
     TRY_SQL
     std::string opration = "describe " + table_name;
     mysqlpp::Query query = _conn.query(opration);
     mysqlpp::StoreQueryResult res = query.store();

     int field_num = res.size();
     for (int i = ; i < field_num; ++i)
     {
         mysql_field_info field_i;

         field_i.Field   = res[i]["field"].c_str();
         field_i.Type    = res[i]["type"].c_str();
         field_i.Null    = res[i]["null"].c_str();
         field_i.Key     = res[i]["key"].c_str();
         field_i.Default = res[i]["default"].c_str();
         field_i.Extra   = res[i]["extra"].c_str();

         tbl_info.push_back(field_i);
     }
     CATCH_SQL_ERROR
     return true;
 }

 void DMMySQL::disconnect_mysql()
 {
     _conn.disconnect();
 }

 bool DMMySQL::insert_mysql(std::string sql)
 {
     TRY_SQL
     mysqlpp::Query query = _conn.query(sql);
     query.execute();
     CATCH_SQL_ERROR
     return true;
 }

完整代码参考：https://github.com/binchen-china/DMServer