leetcode_cpp/redis/redis_handler.cpp

/*
 * @Description:
 * @Version: 1.0
 * @Autor: zhuyijun
 * @Date: 2021-11-17 09:36:12
 * @LastEditTime: 2021-11-17 09:36:12
 */
#include "redis_handler.h"

#include <cstring>
#include <iostream>
#include <string>
using namespace std;

RedisHandler::RedisHandler() {
  m_addr = "";
  m_port = 0;
  m_pwd = "";
  pm_rct = NULL;
  pm_rr = NULL;
  error_msg = "";
}

RedisHandler::~RedisHandler() {
  disConnect();
  pm_rct = NULL;
  pm_rr = NULL;
}

/*
连接redis数据库
addr: 地址，port：端口号，pwd：密码
成功返回M_REDIS_OK，失败返回M_CONNECT_FAIL
*/
int RedisHandler::connect(const string &addr = "127.0.0.1", int port = 6379,
                          const string &pwd) {
  m_addr = addr;
  m_port = port;
  m_pwd = pwd;

  pm_rct = redisConnect(m_addr.c_str(), m_port);

  if (pm_rct->err) {
    error_msg = pm_rct->errstr;
    return M_CONNECT_FAIL;
  }

  if (!m_pwd.empty()) {
    return connectAuth(m_pwd);
  }

  return M_REDIS_OK;
}

/*
断开redis连接
*/
int RedisHandler::disConnect() {
  redisFree(pm_rct);
  freeReplyObject(pm_rr);
}

/*
添加或插入键值对
key：键，value：值
成功返回M_REDIS_OK，失败返回<0
*/
int RedisHandler::setValue(const string &key, const string &value) {
  string cmd = "set " + key + " " + value;

  pm_rr = (redisReply *)redisCommand(pm_rct, cmd.c_str());

  return handleReply();
}

/*
获取键对应的值
key：键，value：值引用
成功返回M_REDIS_OK，失败返回<0
*/
int RedisHandler::getValue(const string &key, string &value) {
  string cmd = "get " + key;

  pm_rr = (redisReply *)redisCommand(pm_rct, cmd.c_str());

  int ret = handleReply(&value);
}

/*
删除键
key：键
成功返回影响的行数（可能为0），失败返回<0
*/
int RedisHandler::delKey(const string &key) {
  string cmd = "del " + key;

  pm_rr = (redisReply *)redisCommand(pm_rct, cmd.c_str());

  int rows = 0;
  int ret = handleReply(&rows);
  if (ret == M_REDIS_OK)
    return rows;
  else
    return ret;
}

/*
打印所有键值对到屏幕上
*/
int RedisHandler::printAll() {
  string cmd = "keys *";

  pm_rr = (redisReply *)redisCommand(pm_rct, cmd.c_str());

  int len;
  redisReply **array;
  int ret = handleReply(&len, &array);
  if (ret == M_REDIS_OK) {
    for (int i = 0; i < len; i++) cout << string(array[i]->str) << endl;
  } else
    return 0;
}

/*
返回错误信息
*/
string RedisHandler::getErrorMsg() { return error_msg; }

/*
使用密码登录
psw：登录密码
成功返回M_REDIS_OK，失败返回<0
*/
int RedisHandler::connectAuth(const string &psw) {
  string cmd = "auth " + psw;

  pm_rr = (redisReply *)redisCommand(pm_rct, cmd.c_str());

  return handleReply();
}

/*
处理redis返回的信息
value：数据指针，用于保存redis返回的基本类型（value指针指向该数据）
array：数组指针，用于保存redis返回的数组
成功返回M_REDIS_OK，失败返回<0
*/
int RedisHandler::handleReply(void *value, redisReply ***array) {
  if (pm_rct->err) {
    error_msg = pm_rct->errstr;
    return M_CONTEXT_ERROR;
  }

  if (pm_rr == NULL) {
    error_msg = "auth redisReply is NULL";
    return M_REPLY_ERROR;
  }

  switch (pm_rr->type) {
    case REDIS_REPLY_ERROR:
      error_msg = pm_rr->str;
      return M_EXE_COMMAND_ERROR;
    case REDIS_REPLY_STATUS:
      if (!strcmp(pm_rr->str, "OK"))
        return M_REDIS_OK;
      else {
        error_msg = pm_rr->str;
        return M_EXE_COMMAND_ERROR;
      }
    case REDIS_REPLY_INTEGER:
      *(int *)value = pm_rr->integer;
      return M_REDIS_OK;
    case REDIS_REPLY_STRING:
      *(string *)value = pm_rr->str;
      return M_REDIS_OK;
    case REDIS_REPLY_NIL:
      *(string *)value = "";
      return M_REDIS_OK;
    case REDIS_REPLY_ARRAY:
      *(int *)value = pm_rr->elements;
      *array = pm_rr->element;
      return M_REDIS_OK;
    default:
      error_msg = "unknow reply type";
      return M_EXE_COMMAND_ERROR;
  }
}