PHP使用Redis的List(列表)命令實現消息隊列

1.用到的List(列表)命令

命令	作用
lPush	將一個或多個值插入到列表頭部
rpoplpush	彈出列表最後一個值，同時插入到另一個列表頭部，並返回該值
lRem	刪除列表內的給定值
lIndex	按索引獲取列表內的值

2.隊列的組成

名稱	職責
生產者	發佈消息
消費者	獲取並處理消息
監聽者	監聽超時的消息，彈回原消息隊列，確保消費者掛掉後或處理失敗後消息能被其他消費者處理

3.php實現代碼

生產者Producter.php

<?php
/**
 * Created by PhpStorm.
 * User: jmsite.cn
 * Date: 2019/1/26
 * Time: 0:13
 */
try {
    //聲明消息隊列-list的鍵名
    $queueKey = 'testQueueKey';
    $redis = new Redis();
    $redis->connect('192.168.75.132', 6379);
    //向列表中push10條消息
    for ($i = 0;$i < 10;$i++){
        //爲消息生成唯一標識
        $uniqid = uniqid(mt_rand(10000, 99999).getmypid().memory_get_usage(), true);
        $ret = $redis->lPush($queueKey, json_encode(array('uniqid' => $uniqid, 'key' => 'key-'.$i, 'value' => 'data')));
        var_dump($ret);
    }

} catch (Exception $e){
    echo $e->getMessage();
}

消費者Consumer.php

<?php
/**
 * Created by PhpStorm.
 * User: jmsite.cn
 * Date: 2019/1/26
 * Time: 0:14
 */
try {
    //聲明消息隊列-list的鍵名
    $queueKey = 'testQueueKey';
    //聲明監聽者隊列-list的鍵名
    $watchQueueKey = 'watchQueueKey';
    $redis = new Redis();
    $redis->connect('192.168.75.132', 6379);
    //隊列先進先出，彈出最先加入的消息，同時放入監聽隊列
    while (true){
        $ret = $redis->rpoplpush($queueKey, $watchQueueKey);
        if ($ret === false){
            sleep(1);
        } else {
            $retArray = json_decode($ret, true);
            //將唯一id寫入緩存設置有效期
            $redis->setex($retArray['uniqid'], 60, 0);
            //模擬失敗
            $rand = mt_rand(0,9);
            if ($rand < 3){
                echo "failure:".$ret."\n";
            } else {
                //todo
                //處理成功移除消息
                $redis->lRem($watchQueueKey, $ret, 0);
                echo "success:".$ret."\n";
            }
        }
    }

} catch (Exception $e){
    echo $e->getMessage();
}

監聽者Watcher.php

<?php
/**
 * Created by PhpStorm.
 * User: jmsite.cn
 * Date: 2019/1/26
 * Time: 0:15
 */
try {
    //聲明消息隊列-list的鍵名
    $queueKey = 'testQueueKey';
    //聲明監聽者隊列-list的鍵名
    $watchQueueKey = 'watchQueueKey';
    $redis = new Redis();
    $redis->connect('192.168.75.132', 6379);

    while (true){
        //取出列表尾部的一個值
        $ret = $redis->lIndex($watchQueueKey, -1);
        //如果不存在則休眠1秒
        if ($ret === false){
            sleep(1);
        } else {
            $retArray = json_decode($ret, true);
            $idCache = $redis->get($retArray['uniqid']);
            if ($idCache === false){
                //如果已過期，表示任務超時，彈回原隊列
                $redis->rpoplpush($watchQueueKey, $queueKey);
                echo "rpoplpush:".$ret."\n";
            } else {
                //處理中，繼續等待
                sleep(1);
            }
        }
    }

} catch (Exception $e){
    echo $e->getMessage();
}

4.執行隊列

開啓監聽者php Watcher.php
開啓消費者php Consumer.php
執行生產者php Producter.php
生產者輸出

int(1)
int(2)
int(3)
int(4)
int(5)
int(6)
int(7)
int(8)
int(9)
int(10)

監聽者輸出

rpoplpush:{"uniqid":"28580267323642245c4bde640dd8f3.30292468","key":"key-1","value":"data"}
rpoplpush:{"uniqid":"10258267323642245c4bde640e1cd9.95656605","key":"key-4","value":"data"}
rpoplpush:{"uniqid":"43356267323642245c4bde640e88e9.50566706","key":"key-5","value":"data"}
rpoplpush:{"uniqid":"59823267323642245c4bde640e98b5.51512314","key":"key-6","value":"data"}
rpoplpush:{"uniqid":"83293267323642245c4bde640ed753.04622366","key":"key-9","value":"data"}
rpoplpush:{"uniqid":"59823267323642245c4bde640e98b5.51512314","key":"key-6","value":"data"}

消費者輸出

success:{"uniqid":"47280267323557445c4bde640dbfb4.78962728","key":"key-0","value":"data"}
failure:{"uniqid":"28580267323642245c4bde640dd8f3.30292468","key":"key-1","value":"data"}
success:{"uniqid":"39394267323642245c4bde640de992.34641654","key":"key-2","value":"data"}
success:{"uniqid":"41335267323642245c4bde640df980.38466514","key":"key-3","value":"data"}
failure:{"uniqid":"10258267323642245c4bde640e1cd9.95656605","key":"key-4","value":"data"}
failure:{"uniqid":"43356267323642245c4bde640e88e9.50566706","key":"key-5","value":"data"}
failure:{"uniqid":"59823267323642245c4bde640e98b5.51512314","key":"key-6","value":"data"}
success:{"uniqid":"43817267323642245c4bde640ec189.44008738","key":"key-7","value":"data"}
success:{"uniqid":"69276267323642245c4bde640ecb91.04877522","key":"key-8","value":"data"}
failure:{"uniqid":"83293267323642245c4bde640ed753.04622366","key":"key-9","value":"data"}
success:{"uniqid":"28580267323642245c4bde640dd8f3.30292468","key":"key-1","value":"data"}
success:{"uniqid":"10258267323642245c4bde640e1cd9.95656605","key":"key-4","value":"data"}
success:{"uniqid":"43356267323642245c4bde640e88e9.50566706","key":"key-5","value":"data"}
failure:{"uniqid":"59823267323642245c4bde640e98b5.51512314","key":"key-6","value":"data"}
success:{"uniqid":"83293267323642245c4bde640ed753.04622366","key":"key-9","value":"data"}
success:{"uniqid":"59823267323642245c4bde640e98b5.51512314","key":"key-6","value":"data"}

我們看到消費者第一次執行時失敗的消息，超時後又被彈回了消息隊列，消費者有了再次執行的機會，監聽者的職責就是確保消費者執行失敗或掛掉後消息還能再彈回原隊列得到再次執行
原文地址：https://www.jmsite.cn/blog-615.html