使用hiredis 实现异步设置发布订阅模式

通过libevent实现订阅的回调事件

发布端代码如下：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>

#include <hiredis/hiredis.h>
#include <hiredis/async.h>
#include <hiredis/adapters/libevent.h>

void getCallback(redisAsyncContext *c, void *r, void *privdata) {
    redisReply *reply = r;
    if (reply == NULL) {
        if (c->errstr) {
            printf("errstr: %s\n", c->errstr);
        }
        return;
    }
    printf("%d\n",reply->elements);
    /* Disconnect after receiving the reply to GET */
    redisAsyncDisconnect(c);
}

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("Disconnected...\n");
}

int main (int argc, char **argv) {
#ifndef _WIN32
    signal(SIGPIPE, SIG_IGN);
#endif

    struct event_base *base = event_base_new();
    redisOptions options = {0};
    REDIS_OPTIONS_SET_TCP(&options, "192.168.100.204", 6379);
    struct timeval tv = {0};
    tv.tv_sec = 1;
    options.connect_timeout = &tv;

    redisAsyncContext *c = redisAsyncConnectWithOptions(&options);
    if (c->err) {
        /* Let *c leak for now... */
        printf("Error: %s\n", c->errstr);
        return 1;
    }

    redisLibeventAttach(c,base);
    redisAsyncSetConnectCallback(c,connectCallback);
    redisAsyncSetDisconnectCallback(c,disconnectCallback);
    char user_password[]="123456";
    redisAsyncCommand(c, NULL, NULL, "AUTH %s", user_password);
    redisAsyncCommand(c, getCallback, NULL，"PUBLISH runoobChat %s","nihao");
    //redisAsyncCommand(c, getCallback, (char*)"end-1", "GET key");
    event_base_dispatch(base);
    return 0;
}

编译命令

gcc pub.c -o pub -lhiredis -levent

订阅端代码如下：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <signal.h>

#include <hiredis/hiredis.h>
#include <hiredis/async.h>
#include <hiredis/adapters/libevent.h>

void getCallback(redisAsyncContext *c, void *r, void *privdata) {
    redisReply *reply = r;
    if (reply == NULL) {
        if (c->errstr) {
            printf("errstr: %s\n", c->errstr);
        }
        return;
    }
    printf("redisReply size:%d\n",reply->elements);        
    printf("redisReply size:%s\n",reply->element[0]->str);        
    printf("redisReply size:%s\n",reply->element[1]->str);        
    printf("redisReply size:%s\n",reply->element[2]->str);        
    //printf("argv[%s]: %s\n", (char*)privdata, reply->str);

    /* Disconnect after receiving the reply to GET */
    //redisAsyncDisconnect(c);
}

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("Disconnected...\n");
}

int main (int argc, char **argv) {
#ifndef _WIN32
    signal(SIGPIPE, SIG_IGN);
#endif

    struct event_base *base = event_base_new();
    redisOptions options = {0};
    REDIS_OPTIONS_SET_TCP(&options, "192.168.100.204", 6379);
    struct timeval tv = {0};
    tv.tv_sec = 1;
    options.connect_timeout = &tv;

    redisAsyncContext *c = redisAsyncConnectWithOptions(&options);
    if (c->err) {
        /* Let *c leak for now... */
        printf("Error: %s\n", c->errstr);
        return 1;
    }

    redisLibeventAttach(c,base);
    redisAsyncSetConnectCallback(c,connectCallback);
    redisAsyncSetDisconnectCallback(c,disconnectCallback);
    char user_password[]="123456";
    redisAsyncCommand(c, NULL, NULL, "AUTH %s", user_password);
    //redisAsyncCommand(c, NULL, NULL, "SUBSCRIBE runoobChat");

    redisAsyncCommand(c, getCallback, "SUBSCRIBE", "SUBSCRIBE runoobChat");
    event_base_dispatch(base);
    return 0;
}

编译命令：

gcc sub.c -o sub -lhiredis -levent

需要先起订阅端，在起发布端：

输出如下