php - RabbitMQ 和 PHP 如何将任务返回到队列？

Question

如果处理结果不适合我，我如何将消息返回到队列中。仅找到有关消息确认的信息，但我认为它不适合我。如果作为处理的结果，我需要将参数 RETRY 消息添加回队列。然后这个 worker 或另一个 worker 再次拿起它并尝试处理它。

例如:

<?php
use PhpAmqpLib\Connection\AMQPStreamConnection;

echo ' [*] Waiting for messages. To exit press CTRL+C', "\n";

$connection = new AMQPStreamConnection($AMQP);
$channel = $connection->channel();

$channel->queue_declare('test', false, false, false, false);

$callback = function($msg) {
    $condition = json_decode($msg->body);

    if (!$condition) {
        # return to the queue
    }
};

$channel->basic_consume('test', '', false, true, false, false, $callback);

while(count($channel->callbacks)) {
    $channel->wait();
}

$channel->close();
$connection->close();
?>

Answer 1

将自动 no_ack 标志设置为 false

queue: Queue from where to get the messages
consumer_tag: Consumer identifier
no_local: Don't receive messages published by this consumer.
no_ack: Tells the server if the consumer will acknowledge the messages.
exclusive: Request exclusive consumer access, meaning only this consumer can access the queue
nowait:
callback: A PHP Callback

$channel->basic_consume('test', '', false, false, false, false, $callback);

你必须使用确认，如果你的进程不工作你可以忽略确认

<?php
use PhpAmqpLib\Connection\AMQPStreamConnection;

echo ' [*] Waiting for messages. To exit press CTRL+C', "\n";

$connection = new AMQPStreamConnection($AMQP);
$channel = $connection->channel();

$channel->queue_declare('test', false, false, false, false);

$callback = function($message) {
    $condition = json_decode($message->body);
     
    if (!$condition) {
        // return to the queue 
        $message->delivery_info['channel']->basic_nack($message->delivery_info['delivery_tag']);
    }else{
        // send ack , remove from queue
        $message->delivery_info['channel']->basic_ack($message->delivery_info['delivery_tag']);
    }
};

$channel->basic_consume('test', '', false, false, false, false, $callback);

while(count($channel->callbacks)) {
    $channel->wait();
}

$channel->close();
$connection->close();

当然，使用这种方法，您将面对始终位于队列头部的消息，还有另一种可能性，如果你真的想要重试的轨迹，你可以按照下面的方法

为重试定义一个队列，最好是你的队列名 -retry 并且最好定义一个死信队列:-dlq

然后你可以做如下的事情:如何设置-retry队列:这是其中最重要的部分。您需要声明具有以下功能的队列:

x-dead-letter-exchange: 应该和你的主队列路由键相同
x-dead-letter-routing-key: 应该和你的主队列路由键相同
x-message-ttl:重试之间的延迟

代码是sudo代码，请不要复制粘贴，这只是给你一个提示

$maximumRetry = 5;
$callback = function($message) {
    $body = json_decode($message->body);
    try { 
        // process result is your condition
        $message->delivery_info['channel']->basic_ack($message->delivery_info['delivery_tag']);
    } catch(Exception $e) {
        // return to the queue 
        $body['try_attempt'] = !empty($body['try_attempt'])? int($body['try_attempt']) + 1: 1 
        if ($body['try_attempt'] >= $maximumRetry ){
            $message->delivery_info['channel']->basic_nack($message->delivery_info['delivery_tag']);
            return
        }
        $msg = new AMQPMessage(json_encode($message));

        $channel->basic_publish($msg, '', 'test-retry');
    }
};

我们需要 3 个队列来重新绑定(bind)。

• queue.example

  • 绑定(bind):
    • 交换:queue.exchange
    • 路由:queue.example
  • 特点:
    • x-dead-letter-exchange: queue.exchange
    • x-dead-letter-routing-key: queue.example-dlq

• queue.example-dlq

  • 绑定(bind):
    • 交换:queue.exchange
    • 路由:queue.example-dlq

• queue.example-retry

  • 绑定(bind):
    • 交换:queue.exchange
    • 路由:queue.example-retry
  • 特点:
    • x-dead-letter-exchange: queue.exchange
    • x-dead-letter-routing-key: queue.example-added
    • x-消息-ttl:10000

------------更新------------

Quorum 队列提供开箱即用的功能，因此在消费者中，您可以了解每条消息被重试的次数，您还可以轻松地为其定义一个死信队列，有关更多信息，您可以阅读有关 quorom queues 的更多信息和毒药 message handling