redis的C/C++ API

1. hiredis

这时redis自带的官方的C语言API。安装很简单：

# cd {redis-src}
# cd deps/hiredis/
# make
# make install

现在hiredis已经被安装于/usr/local/include/hiredis/和/usr/local/lib/下。为了方便，设置一下头文件和lib文件的路径：

# vim ~/.bashrc

#compile time, paths to search included headers, referenced libs;
export C_INCLUDE_PATH=.:/usr/local/include/hiredis:$C_INCLUDE_PATH
export CPLUS_INCLUDE_PATH=.:/usr/local/include/hiredis:$CPLUS_INCLUDE_PATH
export LIBRARY_PATH=.:/usr/local/lib:$LIBRARY_PATH

#runtime, paths to search referenced libs;
export LD_LIBRARY_PATH=.:/usr/local/lib:$LD_LIBRARY_PATH

然后，就可以基于hiredis API开发客户端了。可是hiredis不支持集群。支持集群的API：

C++  https://github.com/eyjian/r3c

C++  https://github.com/zhengshuxin/acl

C    https://github.com/vipshop/hiredis-vip.git

这里简单测试一下hiredis-vip。

2. hiredis-vip:

hiredis-vip是基于hiredis的(事实上，它包含一个完整的hiredis)，在hiredis的基础上，提供了一套cluster版本的接口。

安装: 由于hiredis-vip包含了完整的hiredis，在安装hiredis-vip之前，先卸载前面安装的hiredis。

# rm -fr /usr/local/include/hiredis/
# rm -f /usr/local/lib/libhiredis.*

安装hiredis-vip

# wget https://github.com/vipshop/hiredis-vip/archive/master.zip
# unzip master.zip
# cd hiredis-vip-master/
# make
# vim Makefile (更改INSTALL_LIBRARY_PATH，免得受系统环境变量LIBRARY_PATH影响)；
INSTALL_LIBRARY_PATH=/usr/local/lib/hiredis-vip
# make install

现在，头文件安装于/usr/local/include/hiredis-vip目录，包含hiredis.h，hircluster.h等；lib文件安装于/usr/local/lib/hiredis-vip目录，主要是libhiredis_vip.so；为了方便，设置一下头文件和lib文件的路径：

# vim ~/.bashrc
#compile time, paths to search included headers, referenced libs;
export C_INCLUDE_PATH=.:/usr/local/include/hiredis-vip:$C_INCLUDE_PATH
export CPLUS_INCLUDE_PATH=.:/usr/local/include/hiredis-vip:$CPLUS_INCLUDE_PATH
export LIBRARY_PATH=.:/usr/local/lib/hiredis-vip:$LIBRARY_PATH


#runtime, paths to search referenced libs;
export LD_LIBRARY_PATH=.:/usr/local/lib/hiredis-vip:$LD_LIBRARY_PATH

2.1 hiredis-vip sync API

#include<stdio.h>
#include<hircluster.h>

int main()
{
    redisClusterContext *cc = redisClusterConnect("127.0.0.1:7000,127.0.0.1:7001",HIRCLUSTER_FLAG_NULL);
    if(cc == NULL || cc->err)
    {
        printf("connect error : %s\n", cc == NULL ? "NULL" : cc->errstr);
        return -1;
    }

    int i;
    redisReply* reply = NULL;

    for(i=0; i<10000; i++)
    {
      //set
      reply = redisClusterCommand(cc, "set key%d value%d", i, i);
      if(reply == NULL)
      {
        printf("set key%d, reply is NULL, error info: %s\n", i, cc->errstr);
        redisClusterFree(cc);
        return -1;
      }
      printf("set key%d, reply:%s\n", i, reply->str);
      freeReplyObject(reply);

      //get
      reply = redisClusterCommand(cc, "get key%d", i);
      if(reply == NULL)
      {
        printf("get key%d, reply is NULL, error info: %s\n", i, cc->errstr);
        redisClusterFree(cc);
        return -1;
      }
      printf("get key%d, reply:%s\n", i, reply->str);
      freeReplyObject(reply);
    }

    redisClusterFree(cc);
    return 0;
}

编译运行：

<pre name="code" class="plain"># gcc -lhiredis_vip sync.c
# ./a.out
......
set key9998, reply:OK
get key9998, reply:value9998
set key9999, reply:OK
get key9999, reply:value9999

2.2 hiredis-vipi async API

#include<stdio.h>
#include<hircluster.h>
#include<adapters/libevent.h>

int all_count=0;

void getCallback(redisClusterAsyncContext *acc, void *r, void *privdata)
{
    redisReply *reply = r;
    int count =  *(int*)privdata;
    all_count ++;
    if(all_count >= count)
    {
        redisClusterAsyncDisconnect(acc);
    }
}

void connectCallback(const redisAsyncContext *c, int status)
{
    if (status != REDIS_OK) {
        printf("Error: %s\n", c->errstr);
        return;
    }
    printf("Connected...\n");
}

void disconnectCallback(const redisAsyncContext *c, int status)
{
    if (status != REDIS_OK) {
        printf("Error: %s\n", c->errstr);
        return;
    }

    printf("\nDisconnected...\n");
}

int main(int argc, char **argv)
{
    int status;
    struct event_base *base = event_base_new();
    redisClusterAsyncContext *acc = redisClusterAsyncConnect("127.0.0.1:7001,127.0.0.1:7001",HIRCLUSTER_FLAG_NULL);
    if (acc->err)
    {
        printf("Error: %s\n", acc->errstr);
        return 1;
    }
    redisClusterLibeventAttach(acc,base);
    redisClusterAsyncSetConnectCallback(acc,connectCallback);
    redisClusterAsyncSetDisconnectCallback(acc,disconnectCallback);

    int count = 10000;
    int i;
    for(i = 0; i < 10000; i ++)
    {
        status = redisClusterAsyncCommand(acc, getCallback, &count, "set %d %d", i, i);
        if(status != REDIS_OK)
        {
            printf("error: %d %s\n", acc->err, acc->errstr);
        }
    }

    event_base_dispatch(base);
    return 0;
}

编译运行：

# gcc -lhiredis_vip -levent async.c
# ./a.out
Connected...
Connected...
Connected...

Disconnected...

Disconnected...

Disconnected...