创建Client实例

客户端工厂类

  1. namespace pegasus {
  2. class pegasus_client_factory
  3. {
  4. public:
  5.     ///
  6.     /// \brief initialize
  7.     /// initialize pegasus client lib. must call this function before anything else.
  8.     /// \param config_file
  9.     /// the configuration file of client lib
  10.     /// \return
  11.     /// true indicate the initailize is success.
  12.     ///
  13.     static bool initialize(const char *config_file);
  15.     ///
  16.     /// \brief get_client
  17.     /// get an instance for a given cluster and a given app name.
  18.     /// \param cluster_name
  19.     /// the pegasus cluster name.
  20.     /// a cluster can have multiple apps.
  21.     /// \param app_name
  22.     /// an app is a logical isolated k-v store.
  23.     /// a cluster can have multiple apps.
  24.     /// \return
  25.     /// the client instance. DO NOT delete this client even after usage.
  26.     static pegasus_client *get_client(const char *cluster_name, const char *app_name);
  27. };
  28. } //end namespace

客户端的初始化，实际上是对rdsn框架初始化

  1. if (!pegasus::pegasus_client_factory::initialize("config.ini")) {
  2.     fprintf(stderr, "ERROR: init pegasus failed\n");
  3.     return -1;
  4. }
  5. /**succeed， continue**/

注：

  • 参数：config_file 见 配置文件 的介绍
  • 返回值：bool值，true代表初始化成功，false初始化失败
  • 该函数只需在一个进程生命周期内调用一次即可，并且非线程安全的获取客户端
  1. pegasus::pegasus_client* pg_client = pegasus::pegasus_client_factory::get_client("cluster_name", "table_name");
  2. if (pg_client == nullptr) {
  3.     fprintf(stderr, "ERROR: get pegasus client failed\n");
  4.     return -1;
  5. }
  6. /***  do what you want with pg_client ****/

注意： get_client返回值不能明确的调用delete，也不能用智能指针封装，框架在停止的时候自动释放（底层使用单例来保存）