C++ 使用 hiredis 封装redis 的数据获取接口

整合自互联网

一、hiredis 类库的安装

tar -zxvf hiredis-v0.13.3.tar.gz

make
make install

mkdir /usr/lib/hiredis
cp libhiredis.so /usr/lib/
//将动态连接库libhiredis.so至/usr/lib/
mkdir /usr/include/hiredis
cp hiredis.h /usr/include/hiredis   //头文件包含#include<hiredis/hiredis.h>

二、封装 redisUtil.h 访问 实现 redis 的连接，按 key 来获取各个类型的数据

redisUtils.h

/*
 * redis.h
 *
 *  Created on: 2018年6月7日
 *      Author: oftenlin
 */

#ifndef REDIS_H_
#define REDIS_H_

#include <iostream>
#include <string.h>
#include <string>
#include <stdio.h>
#include <hiredis/hiredis.h>

class Redis
{
    public:
        Redis();
        ~Redis();
        bool connect(std::string host, int port);
        std::string get(std::string key);
        void set(std::string key, std::string value);
        std::string hget(const char* key,const  char* hkey);
        int existsKey(const char* ID);
        int del(const char* key);
        int hset(const char* key,const char* hkey,const char* hvalue, size_t hvaluelen);
        int hset(const char* key, const char* hkey, const char* value);
        void lpush(std::string key, std::string value);
        int lget(std::string key,int begin_index,int end_index);
    private:
        redisContext* _connect;
        redisReply* _reply;

};

#endif /* REDIS_H_ */

redisUtils.cpp

 /*
  * redis.cpp
  *
  *  Created on: 2018年6月7日
  *      Author: oftenlin
  */

 #include "redis.h"

 Redis::Redis(){

 }

 Redis::~Redis()
 {
     this->_connect = NULL;
     this->_reply = NULL;
 }

 bool Redis::connect(std::string host, int port)
 {
     this->_connect = redisConnect(host.c_str(), port);
     if(this->_connect != NULL && this->_connect->err)
     {
         printf("connect error: %s\n", this->_connect->errstr);
         return ;
     }
     return ;
 }

 std::string Redis::get(std::string key)
 {
     std::string str ="";
     this->_reply = (redisReply*)redisCommand(this->_connect, "GET %s", key.c_str());
     if(this->_reply==NULL){
         return str;
     }
     str = this->_reply->str;
     freeReplyObject(this->_reply);
     return str;

 }

 void Redis::set(std::string key, std::string value)
 {
     redisCommand(this->_connect, "SET %s %s", key.c_str(), value.c_str());
 }

 void Redis::lpush(std::string key, std::string value)
 {
     redisCommand(this->_connect, "LPUSH %s %s", key.c_str(), value.c_str());
 }

 int Redis::lget(std::string key,int begin_index,int end_index){
     /* Let's check what we have inside the list */
     redisReply* reply = (redisReply*) redisCommand(this->_connect,"LRANGE %s %d %d",key.c_str(),begin_index,end_index);
     if (reply->type == REDIS_REPLY_ARRAY) {
         for (int j = ; j < reply->elements; j++) {
             printf("%u) %s\n", j, reply->element[j]->str);
 //            data.push_back(_reply->element[j]->str);

         }
     }
     freeReplyObject(reply);
     return ;
 }

 std::string Redis::hget(const char* key,const  char* hkey){
     const char* argv[];
     size_t argvlen[];
     argv[] = "HGET";
     argvlen[] = ;
     argv[] = key;
     argvlen[] = strlen(key);
     argv[] = hkey;
     argvlen[] = strlen(hkey);
     redisReply* reply =(redisReply*) redisCommandArgv(this->_connect, , argv, argvlen);
     std::string value;
     if(reply->type != REDIS_REPLY_NIL){
         value = std::string(reply->str,reply->str + reply->len);
     }
     freeReplyObject(reply);
     return value;
 }
 int Redis::hset(const char* key, const char* hkey, const char* value){
     redisReply* reply =(redisReply*) redisCommand(this->_connect, "HSET %s %s %s",key,hkey, value);
     freeReplyObject(reply);
     return ;
 }
 int Redis::hset(const char* key,const char* hkey,const char* hvalue, size_t hvaluelen){
     const char* argv[];
     size_t argvlen[];
     argv[] = "HSET";
     argvlen[] = ;
     argv[] = key;
     argvlen[] = strlen(key);
     argv[] = hkey;
     argvlen[] = strlen(hkey);
     argv[] = hvalue;
     argvlen[] = hvaluelen;
     redisReply * reply =(redisReply*) redisCommandArgv(this->_connect, , argv, argvlen);
     freeReplyObject(reply);
     return ;
 }

 int Redis::del(const char* key){
     int res = ;
     redisReply* reply = (redisReply*)redisCommand(this->_connect, "DEL %s", key);
     if(reply->type == REDIS_REPLY_INTEGER){
         if(reply->integer == 1L)
             res = ;
     }
     freeReplyObject(reply);
     return res;
 }

 /*if Key ID exists*/
 int Redis::existsKey(const char* ID){
     redisReply * reply = (redisReply*)redisCommand(this->_connect,"exists %s",ID);
     int res = ;
     if(reply->type == REDIS_REPLY_INTEGER){
         if(reply->integer == 1L)
             res  = ;
     }
     freeReplyObject(reply);
     return res;
 }

三、使用示例

#include "write2db/redis.h"
int main(int argc, char **argv) {
    Redis *r = new Redis();
    if(!r->connect("localhost", )){
        printf("redis connect error!\n");
    return ;
    }

    std::string time_str = r->get("mykey");

}