最近,我在生产者/消费者队列系统上进行了快速实现。
<?php
namespace Queue;
use PhpAmqpLib\Connection\AMQPStreamConnection;
use PhpAmqpLib\Message\AMQPMessage;
use PhpAmqpLib\Wire\AMQPTable;
class Amqp
{
private $connection;
private $queueName;
private $delayedQueueName;
private $channel;
private $callback;
public function __construct($host, $port, $login, $password, $queueName)
{
$this->connection = new AMQPStreamConnection($host, $port, $login, $password);
$this->queueName = $queueName;
$this->delayedQueueName = null;
$this->channel = $this->connection->channel();
// First, we need to make sure that RabbitMQ will never lose our queue.
// In order to do so, we need to declare it as durable. To do so we pass
// the third parameter to queue_declare as true.
$this->channel->queue_declare($queueName, false, true, false, false);
}
public function __destruct()
{
$this->close();
}
// Just in case : https://dev59.com/R3VC5IYBdhLWcg3w51hv
// We should call close explicitly if possible.
public function close()
{
if (!is_null($this->channel)) {
$this->channel->close();
$this->channel = null;
}
if (!is_null($this->connection)) {
$this->connection->close();
$this->connection = null;
}
}
public function produceWithDelay($data, $delay)
{
if (is_null($this->delayedQueueName))
{
$delayedQueueName = $this->queueName . '.delayed';
// First, we need to make sure that RabbitMQ will never lose our queue.
// In order to do so, we need to declare it as durable. To do so we pass
// the third parameter to queue_declare as true.
$this->channel->queue_declare($this->delayedQueueName, false, true, false, false, false,
new AMQPTable(array(
'x-dead-letter-exchange' => '',
'x-dead-letter-routing-key' => $this->queueName
))
);
$this->delayedQueueName = $delayedQueueName;
}
$msg = new AMQPMessage(
$data,
array(
'delivery_mode' => AMQPMessage::DELIVERY_MODE_PERSISTENT,
'expiration' => $delay
)
);
$this->channel->basic_publish($msg, '', $this->delayedQueueName);
}
public function produce($data)
{
$msg = new AMQPMessage(
$data,
array('delivery_mode' => AMQPMessage::DELIVERY_MODE_PERSISTENT)
);
$this->channel->basic_publish($msg, '', $this->queueName);
}
public function consume($callback)
{
$this->callback = $callback;
// This tells RabbitMQ not to give more than one message to a worker at
// a time.
$this->channel->basic_qos(null, 1, null);
// Requires ack.
$this->channel->basic_consume($this->queueName, '', false, false, false, false, array($this, 'consumeCallback'));
while(count($this->channel->callbacks)) {
$this->channel->wait();
}
}
public function consumeCallback($msg)
{
call_user_func_array(
$this->callback,
array($msg)
);
// Very important to ack, in order to remove msg from queue. Ack after
// callback, as exception might happen in callback.
$msg->delivery_info['channel']->basic_ack($msg->delivery_info['delivery_tag']);
}
public function getQueueSize()
{
// three tuple containing (<queue name>, <message count>, <consumer count>)
$tuple = $this->channel->queue_declare($this->queueName, false, true, false, false);
if ($tuple != null && isset($tuple[1])) {
return $tuple[1];
}
return -1;
}
}
public function produce
和public function consume
的组合按预期工作。
然而,当涉及到延迟队列系统时,public function produceWithDelay
和public function consume
的组合不按预期工作。调用consume
的消费者无法接收到任何项目,即使等待一段时间。
我认为我的produceWithDelay
实现有问题。请问是什么问题?
$channel->queue_declare("name", false, false, false, true, true, array());
,交换机可能跟随此gist。 - vardius