1. List command used

2. Composition of the queue

3.php implementation code

Producer.php

<?php
/**
 * Created by PhpStorm.
 * User: jmsite.cn
 * Date: 2019/1/26
 * Time: 0:13
 */
try {
    //Declare the key name of message queue list
    $queueKey = 'testQueueKey';
    $redis = new Redis();
    $redis->connect('192.168.75.132', 6379);
    //Push 10 messages to the list
    for ($i = 0;$i < 10;$i++){
        //Generate a unique ID for the message
        $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();
}

Consumer.php

<?php
/**
 * Created by PhpStorm.
 * User: jmsite.cn
 * Date: 2019/1/26
 * Time: 0:14
 */
try {
    //Declare the key name of message queue list
    $queueKey = 'testQueueKey';
    //Declare the key name of listener queue list
    $watchQueueKey = 'watchQueueKey';
    $redis = new Redis();
    $redis->connect('192.168.75.132', 6379);
    //Queue first in first out, pop up the first joined message, and put it into the listening queue at the same time
    while (true){
        $ret = $redis->rpoplpush($queueKey, $watchQueueKey);
        if ($ret === false){
            sleep(1);
        } else {
            $retArray = json_decode($ret, true);
            //Write unique id to cache to set validity period
            $redis->setex($retArray['uniqid'], 60, 0);
            //Simulation failure
            $rand = mt_rand(0,9);
            if ($rand < 3){
                echo "failure:".$ret."\n";
            } else {
                //todo
                //Process successfully removed message
                $redis->lRem($watchQueueKey, $ret, 0);
                echo "success:".$ret."\n";
            }
        }
    }

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

Listener Watcher.php

<?php
/**
 * Created by PhpStorm.
 * User: jmsite.cn
 * Date: 2019/1/26
 * Time: 0:15
 */
try {
    //Declare the key name of message queue list
    $queueKey = 'testQueueKey';
    //Declare the key name of listener queue list
    $watchQueueKey = 'watchQueueKey';
    $redis = new Redis();
    $redis->connect('192.168.75.132', 6379);

    while (true){
        //Take a value at the end of the list
        $ret = $redis->lIndex($watchQueueKey, -1);
        //Sleep for 1 second if not present
        if ($ret === false){
            sleep(1);
        } else {
            $retArray = json_decode($ret, true);
            $idCache = $redis->get($retArray['uniqid']);
            if ($idCache === false){
                //If it has expired, it means that the task has timed out and the original queue is bounced back
                $redis->rpoplpush($watchQueueKey, $queueKey);
                echo "rpoplpush:".$ret."\n";
            } else {
                //Processing, continue to wait
                sleep(1);
            }
        }
    }

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

4. Execution queue

Turn on listener php Watcher.php
Open consumer php Consumer.php
Execution producer PHP producer.php
Producer output

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

Monitor output

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"}

Consumer output

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"}

We see that the message that the consumer failed in the first execution is bounced back to the message queue after the timeout. The consumer has the opportunity to execute again. The responsibility of the listener is to ensure that the message can bounce back to the original queue and be executed again after the consumer fails or hangs up
Original address: https://www.jmsite.cn/blog-615.html