RabbitMQ 入门教程(PHP版) 使用rabbitmq-delayed-message-exchange插件实现延迟功能

延迟任务应用场景

场景一:物联网系统经常会遇到向终端下发命令,如果命令一段时间没有应答,就需要设置成超时。

场景二:订单下单之后30分钟后,如果用户没有付钱,则系统自动取消订单。

场景三:过1分钟给新注册会员的用户,发送注册邮件等。

php 使用rabbitmq-delayed-message-exchange插件实现延迟功能

1.安装

下载后解压,并将其拷贝至(使用Linux Debian/RPM部署)rabbitmq服务器目录:/usr/local/rabbitmq/plugins中( windows安装目录\rabbitmq_server-version\plugins ).

2.启用插件

使用命令rabbitmq-plugins enable rabbitmq_delayed_message_exchang启用插件

rabbitmq-plugins enable rabbitmq_delayed_message_exchang

输出如下:

The following plugins have been enabled:
  rabbitmq_delayed_message_exchange

通过rabbitmq-plugins list查看已安装列表,如下:

...
[ ] rabbitmq_delayed_message_exchange 20171215-3.6.x
...

3.机制解释

安装插件后会生成新的Exchange类型x-delayed-message,该类型消息支持延迟投递机制,接收到消息后并未立即将消息投递至目标队列中,而是存储在mnesia(一个分布式数据系统)表中,检测消息延迟时间,如达到可投递时间时并将其通过x-delayed-type类型标记的交换机类型投递至目标队列。

4.php实现过程

消费者 delay_consumer2.php:

<?php

//header('Content-Type:text/html;charset=utf8;');

$params = array(
    'exchangeName' => 'delayed_exchange_test',
    'queueName' => 'delayed_queue_test',
    'routeKey' => 'delayed_route_test',
);
$connectConfig = array(
    'host' => 'localhost',
    'port' => 5672,
    'login' => 'guest',
    'password' => 'guest',
    'vhost' => '/'
);

//var_dump(extension_loaded('amqp'));

//exit();

try {
    $conn = new AMQPConnection($connectConfig);
    $conn->connect();
    if (!$conn->isConnected()) {
        //die('Conexiune esuata');
        //TODO 记录日志
        echo 'rabbit-mq 连接错误:', json_encode($connectConfig);
        exit();
    }
    $channel = new AMQPChannel($conn);
    if (!$channel->isConnected()) {
        // die('Connection through channel failed');
        //TODO 记录日志
        echo 'rabbit-mq Connection through channel failed:', json_encode($connectConfig);
        exit();
    }
    $exchange = new AMQPExchange($channel);
    //$exchange->setFlags(AMQP_DURABLE);//声明一个已存在的交换器的,如果不存在将抛出异常,这个一般用在consume端
    $exchange->setName($params['exchangeName']);
    $exchange->setType('x-delayed-message'); //x-delayed-message类型
    /*RabbitMQ常用的Exchange Type有三种:fanout、direct、topic。

      fanout:把所有发送到该Exchange的消息投递到所有与它绑定的队列中。

      direct:把消息投递到那些binding key与routing key完全匹配的队列中。

      topic:将消息路由到binding key与routing key模式匹配的队列中。*/
    $exchange->setArgument('x-delayed-type','direct');
    $exchange->declareExchange();

    //$channel->startTransaction();

    $queue = new AMQPQueue($channel);
    $queue->setName($params['queueName']);
    $queue->setFlags(AMQP_DURABLE);
    $queue->declareQueue();

    //绑定
    $queue->bind($params['exchangeName'], $params['routeKey']);
} catch(Exception $e) {
    echo $e->getMessage();
    exit();
}

function callback(AMQPEnvelope $message) {
    global $queue;
    if ($message) {
        $body = $message->getBody();
        echo '接收时间:'.date("Y-m-d H:i:s", time()). PHP_EOL;
        echo '接收内容:'.$body . PHP_EOL;
        //为了防止接收端在处理消息时down掉,只有在消息处理完成后才发送ack消息
        $queue->ack($message->getDeliveryTag());
    } else {
        echo 'no message' . PHP_EOL;
    }
}

//$queue->consume('callback');  第一种消费方式,但是会阻塞,程序一直会卡在此处

//第二种消费方式,非阻塞
/*$start = time();
while(true)
{
    $message = $queue->get();
    if(!empty($message))
    {
        echo $message->getBody();
        $queue->ack($message->getDeliveryTag());    //应答,代表该消息已经消费
        $end = time();
        echo '<br>' . ($end - $start);
        exit();
    }
    else
    {
        //echo 'message not found' . PHP_EOL;
    }
}*/

//注意:这里需要注意的是这个方法:$queue->consume,queue对象有两个方法可用于取消息:consume和get。前者是阻塞的,无消息时会被挂起,适合循环中使用;后者则是非阻塞的,取消息时有则取,无则返回false。
//就是说用了consume之后,会同步阻塞,该程序常驻内存,不能用nginx,apache调用。 
$action = '2';

if($action == '1'){
    $queue->consume('callback');  //第一种消费方式,但是会阻塞,程序一直会卡在此处
}else{
    //第二种消费方式,非阻塞
    $start = time();
    while(true)
    {
        $message = $queue->get();
        if(!empty($message))
        {
            echo '接收时间:'.date("Y-m-d H:i:s", time()). PHP_EOL;
            echo '接收内容:'.$message->getBody().PHP_EOL;
            $queue->ack($message->getDeliveryTag());    //应答,代表该消息已经消费
            $end = time();
            echo '运行时间:'.($end - $start).'秒'.PHP_EOL;
            //exit();
        }
        else
        {
            //echo 'message not found' . PHP_EOL;
        }
    }
}

生产者delay_publisher2.php:

<?php

//header('Content-Type:text/html;charset=utf-8;');

$params = array(
    'exchangeName' => 'delayed_exchange_test',
    'queueName' => 'delayed_queue_test',
    'routeKey' => 'delayed_route_test',
);

$connectConfig = array(
    'host' => 'localhost',
    'port' => 5672,
    'login' => 'guest',
    'password' => 'guest',
    'vhost' => '/'
);

//var_dump(extension_loaded('amqp')); 判断是否加载amqp扩展
//exit();
try {
    $conn = new AMQPConnection($connectConfig);
    $conn->connect();
    if (!$conn->isConnected()) {
        //die('Conexiune esuata');
        //TODO 记录日志
        echo 'rabbit-mq 连接错误:', json_encode($connectConfig);
        exit();
    }
    $channel = new AMQPChannel($conn);
    if (!$channel->isConnected()) {
        // die('Connection through channel failed');
        //TODO 记录日志
        echo 'rabbit-mq Connection through channel failed:', json_encode($connectConfig);
        exit();
    }
    $exchange = new AMQPExchange($channel);
    $exchange->setName($params['exchangeName']);
    $exchange->setType('x-delayed-message'); //x-delayed-message类型
    /*RabbitMQ常用的Exchange Type有三种:fanout、direct、topic。

      fanout:把所有发送到该Exchange的消息投递到所有与它绑定的队列中。

      direct:把消息投递到那些binding key与routing key完全匹配的队列中。

      topic:将消息路由到binding key与routing key模式匹配的队列中。*/
    $exchange->setArgument('x-delayed-type','direct');
    $exchange->declareExchange();

    //$channel->startTransaction();
    //RabbitMQ不容许声明2个相同名称、配置不同的Queue,否则报错
    $queue = new AMQPQueue($channel);
    $queue->setName($params['queueName']);
    $queue->setFlags(AMQP_DURABLE);
    $queue->declareQueue();

    //绑定队列和交换机
    $queue->bind($params['exchangeName'], $params['routeKey']);
    //$channel->commitTransaction();
} catch(Exception $e) {

}

for($i=5;$i>0;$i--){
    //生成消息
    echo '发送时间:'.date("Y-m-d H:i:s", time()).PHP_EOL;
    echo 'i='.$i.',延迟'.$i.'秒'.PHP_EOL;
    $message = json_encode(['order_id'=>time(),'i'=>$i]);
    $exchange->publish($message, $params['routeKey'], AMQP_NOPARAM, ['headers'=>['x-delay'=> 1000*$i]]);
    sleep(2);
}
$conn->disconnect();

对于代码来讲,首先对于消费者核心代码

$exchange->setType('x-delayed-message'); //x-delayed-message类型
$exchange->setArgument('x-delayed-type','direct');

生产者核心代码

$exchange = new AMQPExchange($channel);
$exchange->setName($params['exchangeName']);
$exchange->setType('x-delayed-message'); //x-delayed-message类型
$exchange->setArgument('x-delayed-type','direct');
$exchange->declareExchange();

使用方法:先运行delay_consumer1.php,再运行delay_publisher1.php

运行效果:

 

posted @ 2019-07-01 15:01  一个人的孤独自白  阅读(5598)  评论(0编辑  收藏  举报