PHP实战RabbitMQ之生产者Confirm篇

简介

为提高系统高可用，生产者在发送message需要通过MQ回复ACK来确保message被成功存储。

注：图片来源微信公众号：架构师之路

RabbitMQ官网对Publisher Confirms有相关介绍，可惜example代码没有php版本的，且php-amqplib也是一帮志愿者在维护，精力有限，没有完整的使用example

php-amqblib也有开发者提了Issues希望完善example
https://github.com/php-amqpli...

本文将会使用php来实现Publisher Confirms，希望对大家有所帮助，代码已提交到github:https://github.com/jiaoyang3/...

几种策落

事务

事务可以保证原子性操作RabbitMQ，使用起来也很简单。

$channel->tx_select();//begin trx
$channel->tx_commit();//commit trx
$channel->tx_rollback();//rollback

测试example，运行之后发现没有message提交到queue

<?php

require_once '../../vendor/autoload.php';

use PhpAmqpLib\Message\AMQPMessage;
use RabbitMQ\RabbitMQ;

try {
    $rabbit  = new RabbitMQ();
    $channel = $rabbit->getChannel();
    $channel->tx_select();//begin trx

    $queueName = 'test-single-queue2';
    $rabbit->createQueue($queueName, false, true, false, false);

    for ($i = 0; $i < 10000; $i++) {
        $rabbit->sendMessage($i . "this is a test message.", $queueName, '', [
            'delivery_mode' => AMQPMessage::DELIVERY_MODE_PERSISTENT //消息持久化，重启rabbitmq，消息不会丢失
        ]);
        if ($i == 10) {
            throw new Exception('rollbock');
        }
    }
    $channel->tx_commit();//commit trx
    unset($rabbit);//close
} catch (Exception $e) {
    $channel->tx_rollback();//rollback
    echo $e->getMessage();
}

单条ack

生产者每发送一条message，MQ服务会对出数据进行持久化存储成功之后再回复ack/nack消息给生产者。

开启confirm

$channel->confirm_select();

注册ack/nack回掉方法

//ack callback function
$channel->set_ack_handler(function (AMQPMessage $message){
    echo 'ack' . $message->getBody() . PHP_EOL;
});
//nack callback function
$channel->set_nack_handler(function (AMQPMessage $message){
    echo 'ack' . $message->getBody() .PHP_EOL;
});

设置ack/nack超时时间

    $channel->wait_for_pending_acks_returns(5);//set wait time

测试代码如下，完整代码可访问github

<?php

require_once '../../vendor/autoload.php';

use PhpAmqpLib\Message\AMQPMessage;
use RabbitMQ\RabbitMQ;


$rabbit  = new RabbitMQ();
$channel = $rabbit->getChannel();
$channel->confirm_select();//open confirm
//ack callback function
$channel->set_ack_handler(function (AMQPMessage $message){
    echo 'ack' . $message->getBody() . PHP_EOL;
});
//nack callback function
$channel->set_nack_handler(function (AMQPMessage $message){
    echo 'ack' . $message->getBody() .PHP_EOL;
});

$queueName = 'test-single-queue1';
$rabbit->createQueue($queueName, false, true, false, false);

for ($i = 0; $i < 10000; $i++) {
    $message = $i . "this is a test message.";
    $rabbit->sendMessage($message, $queueName, '', [
        'delivery_mode' => AMQPMessage::DELIVERY_MODE_PERSISTENT
    ]);
    echo $message . '  has been sent' . PHP_EOL;
    $channel->wait_for_pending_acks_returns(5);//set wait time
    sleep(1);
}

unset($rabbit);//关闭连接

多条ack

每条message都ack性能很低
这里进行批量ack，设置每50个message集中ack，代码也很简单

<?php

require_once '../../vendor/autoload.php';

use PhpAmqpLib\Message\AMQPMessage;
use RabbitMQ\RabbitMQ;


$rabbit  = new RabbitMQ();
$channel = $rabbit->getChannel();
$channel->confirm_select();//open confirm
//ack callback function
$channel->set_ack_handler(function (AMQPMessage $message){
    echo 'ack' . $message->getBody() . PHP_EOL;
});
//nack callback function
$channel->set_nack_handler(function (AMQPMessage $message){
    echo 'ack' . $message->getBody() .PHP_EOL;
});


$queueName = 'test-single-queue';
$rabbit->createQueue($queueName, false, true, false, false);

//每次都ack性能很低，批量ack，设置每50个message集中ack
$batchSize               = 50;
$outstandingMessageCount = 0;
for ($i = 0; $i < 10000; $i++) {
    $message = $i . "this is a test message.";
    $rabbit->sendMessage($message, $queueName, '', [
        'delivery_mode' => AMQPMessage::DELIVERY_MODE_PERSISTENT //消息持久化，重启rabbitmq，消息不会丢失
    ]);
    echo $message . '  已发送' . PHP_EOL;
    if (++$outstandingMessageCount == $batchSize) {
        echo '------';
        $channel->wait_for_pending_acks_returns(5);
        $outstandingMessageCount = 0;
    }
    sleep(1);
}
if ($outstandingMessageCount > 0) {
    $channel->wait_for_pending_acks_returns(5);
}

unset($rabbit);//关闭连接

异步ack

毫无疑问，异步的效率是最高的，可惜没有发现php-amqplib并没有实现，一种语言用的人越多生态越好，php已不复当年。