ApsaraMQ for RabbitMQ：用戶端配置自動重連

Java

在用戶端開啟Connection和Topology（Queue、Exchange、Binding、Consumer）自動回復的方法如下：

• factory.setAutomaticRecoveryEnabled(boolean)：用於開啟或關閉Connection自動回復。

• factory.setNetworkRecoveryInterval(long)：用於設定重試時間間隔。如果Connection自動回復異常，設定了Connection自動回復的用戶端將在一段固定時間間隔（預設為5秒）後重試。

• factory.setTopologyRecoveryEnabled(boolean)：用於開啟Topology自動回復。Topology包括Queue、Exchange、Binding、Consumer。

Python

Pika是開源RabbitMQ官方推薦的Python用戶端庫。與Java用戶端提供的串連自動回復功能不同，Pika庫本身不直接支援通過配置來實現自動的串連恢複。因此，要在Python中實現這一功能，您需要通過編寫回呼函數來手動處理串連的恢複過程。

PHP

php-amqplib是一個PHP庫，用於與AMQP協議相容的訊息佇列（如RabbitMQ）進行高效的訊息發布和消費。php-amqplib庫本身不直接支援通過配置來實現自動的串連恢複。因此，要在PHP中實現這一功能，您需要手動處理串連的恢複過程。

Java

開啟Connection和Topology自動回復的用戶端範例程式碼如下：

ConnectionFactory factory = new ConnectionFactory();
// 設定存取點，在雲訊息佇列 RabbitMQ 版控制台執行個體詳情頁面擷取。
factory.setHost("xxx.xxx.aliyuncs.com");
// ${instanceId}為執行個體ID，從雲訊息佇列 RabbitMQ 版控制台執行個體詳情頁面擷取。
factory.setCredentialsProvider(new AliyunCredentialsProvider("${instanceId}"));
// 設定Vhost名稱，請確保已在訊息佇列AMQP版控制台上建立。
factory.setVirtualHost("${VhostName}");
// 預設連接埠，非加密連接埠5672，加密連接埠5671。
factory.setPort(5672);
// 基於網路環境設定合理的逾時時間。
factory.setConnectionTimeout(30 * 1000);
factory.setHandshakeTimeout(30 * 1000);
factory.setShutdownTimeout(0);
// 開啟Connection自動回復。
factory.setAutomaticRecoveryEnabled(true);
// 設定Connection重試時間間隔為10秒。
factory.setNetworkRecoveryInterval(10000);
// 開啟Topology自動回復。
factory.setTopologyRecoveryEnabled(true);
Connection connection = factory.newConnection();                      

Python

Python Pika串連自動回復的消費者用戶端範例程式碼如下：

# -*- coding: utf-8 -*-

import logging
import time
import pika

LOG_FORMAT = ('%(levelname) -10s %(asctime)s %(name) -30s %(funcName) '
              '-35s %(lineno) -5d: %(message)s')
LOGGER = logging.getLogger(__name__)
logging.basicConfig(level=logging.INFO, format=LOG_FORMAT)

class Consumer(object):

    def __init__(self, amqp_url, queue):
        self.should_reconnect = False

        self._connection = None
        self._channel = None
        self._closing = False
        self._url = amqp_url

        self._queue = queue

    def connect(self):
        '''
        建立connection，並設定以下回調：
        on_open_callback: 串連成功回調
        on_open_error_callback: 建立串連失敗回調
        on_close_callback: 串連關閉回調
        '''
        return pika.SelectConnection(
            parameters=pika.URLParameters(self._url),
            on_open_callback=self.on_connection_open,
            on_open_error_callback=self.on_connection_open_error,
            on_close_callback=self.on_connection_closed)

    def on_connection_open(self, _unused_connection):
        '''
        串連成功回調
        建立channel，並設定回調：
        on_channel_open: channel建立成功回調
        '''
        self._connection.channel(on_open_callback=self.on_channel_open)

    def on_connection_open_error(self, _unused_connection, err):
        """
        建立串連失敗回調
        列印錯誤資訊，並嘗試重新串連
        """
        LOGGER.error('Connection open failed: %s', err)
        self.reconnect()

    def on_connection_closed(self, _unused_connection, reason):
        """
        串連關閉回調
        分以下兩種情況：
        1. 正常關閉，直接退出
        2. 串連異常斷開，嘗試重新串連
        """
        self._channel = None
        if self._closing:
            self._connection.ioloop.stop()
        else:
            LOGGER.warning('Connection closed, reconnect necessary: %s', reason)
            self.reconnect()

    def close_connection(self):
        """
        關閉串連
        """
        if self._connection.is_closing or self._connection.is_closed:
            LOGGER.info('Connection is closing or already closed')
        else:
            LOGGER.info('Closing connection')
            self._connection.close()

    def reconnect(self):
        """
        修改should_reconnect為True，並停止io_loop
        """
        self.should_reconnect = True
        self.stop()

    def on_channel_open(self, channel):
        """
        channel建立成功回調
        設定回調：
        on_channel_closed: channel關閉回調
        開始隊列消費
        """
        self._channel = channel
        self._channel.add_on_close_callback(self.on_channel_closed)
        self.start_consuming()

    def on_channel_closed(self, channel, reason):
        """
        channel關閉回調
        列印channel關閉資訊，並關閉串連
        """
        LOGGER.warning('Channel %i was closed: %s', channel, reason)
        self.close_connection()

    def start_consuming(self):
        """
        開始隊列消費
        """
        LOGGER.info('start consuming...')
        self._channel.basic_consume(
            self._queue, self.on_message)

    def on_message(self, _unused_channel, basic_deliver, properties, body):
        """
        消費訊息並上傳ack
        """
        LOGGER.info('Received message: %s', body.decode())
        # 處理商務邏輯
        self._channel.basic_ack(basic_deliver.delivery_tag)

    def run(self):
        """
        建立connection，並啟動io_loop
        """
        self._connection = self.connect()
        self._connection.ioloop.start()

    def stop(self):
        """
        停止io_loop
        """
        if not self._closing:
            self._closing = True
            self._connection.ioloop.stop()
            LOGGER.info('Stopped')


class AutoRecoveryConsumer(object):

    def __init__(self, amqp_url, queue):
        self._amqp_url = amqp_url
        self._queue = queue
        self._consumer = Consumer(self._amqp_url, queue)

    def run(self):
        """
        while True 迴圈，直到KeyboardInterrupt異常
        在run方法中，會啟動io_loop監聽隊列並處理訊息，通過迴圈確保消費者持續運行並且能夠自動重連
        """
        while True:
            try:
                self._consumer.run()
            except KeyboardInterrupt:
                self._consumer.stop()
                break
            self._maybe_reconnect()

    def _maybe_reconnect(self):
        """
        判斷是否需要重連，每次重連間隔1s
        """
        if self._consumer.should_reconnect:
            self._consumer.stop()
            time.sleep(1)
            self._consumer = Consumer(self._amqp_url, self._queue)


def main():
    username = 'MjoxODgwNzcwODY5MD****'
    password = 'NDAxREVDQzI2MjA0OT****'
    host = '1880770****.mq-amqp.cn-hangzhou-a.aliyuncs.com'
    port = 5672
    vhost = 'vhost_test'

    # amqp_url： amqp://<username>:<password>@<host>:<port>/<vhost>
    amqp_url = 'amqp://%s:%s@%s:%i/%s' % (username, password, host, port, vhost)
    consumer = AutoRecoveryConsumer(amqp_url, 'QueueTest')
    consumer.run()


if __name__ == '__main__':
    main()

PHP

PHP php-amqplib串連自動回復的消費者用戶端範例程式碼如下：

<?php

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

use PhpAmqpLib\Connection\AMQPStreamConnection;
use PhpAmqpLib\Exception\AMQPRuntimeException;
use PhpAmqpLib\Exception\AMQPConnectionClosedException;

const ONE_SECOND = 1;


/**
 * 建立串連
 */
function connect() {
    $host = '1880770****.mq-amqp.cn-hangzhou-a.aliyuncs.com';
    $username = 'NDAxREVDQzI2MjA0OT****';
    $password = 'NDAxREVDQzI2MjA0OT****';
    $port = 5672;
    $vhost = 'vhost_test';
    return new AMQPStreamConnection($host, $port, $username, $password, $vhost);
}

/**
 * 清理串連
 */
function cleanup_connection($connection) {
    try {
        if($connection !== null) {
            $connection->close();
        }
    } catch (\ErrorException $e) {
    }
}

$connection = null;

while(true){
    try {
        $connection = connect();
        start_consuming($connection);
    } catch (AMQPConnectionClosedException $e) {
        echo $e->getMessage() . PHP_EOL;
        cleanup_connection($connection);
        sleep(ONE_SECOND);
    } catch(AMQPRuntimeException $e) {
        echo $e->getMessage() . PHP_EOL;
        cleanup_connection($connection);
        sleep(ONE_SECOND);
    } catch(\RuntimeException $e) {
        echo 'Runtime exception ' . PHP_EOL;
        cleanup_connection($connection);
        sleep(ONE_SECOND);
    } catch(\ErrorException $e) {
        echo 'Error exception ' . PHP_EOL;
        cleanup_connection($connection);
        sleep(ONE_SECOND);
    }
}

/**
 * 啟動消費
 * @param AMQPStreamConnection $connection
 */
function start_consuming($connection) {
    $queue = 'queueTest';
    $consumerTag = 'consumer';
    $channel = $connection->channel();
    $channel->queue_declare($queue, false, true, false, false);
    $channel->basic_consume($queue, $consumerTag, false, false, false, false, 'process_message');
    while ($channel->is_consuming()) {
        $channel->wait();
    }
}


/**
 * 處理訊息
 * @param \PhpAmqpLib\Message\AMQPMessage $message
 */
function process_message($message)
{
    // 處理商務邏輯
    echo "\n--------\n";
    echo $message->body;
    echo "\n--------\n";

    $message->ack();
}