rabbitmq ReturnCallback 在 NO_ROUTE(312) 上声明队列时卡住
rabbitmq ReturnCallback stuck while declaring queue on NO_ROUTE(312)
如果没有路由可用，我正在尝试使用发布者 return 的回调来声明队列和绑定，以便不会再次丢弃消息。
这是因为我的队列是自动删除的，如果我的消费者宕机就会被删除。
但是 ReturnCallback 线程卡在 returnedMessage() 中 admin.declareQueue（队列）。
在进一步调试时，我发现它卡在 RabbitAdmin.declareQueue() 中：
DeclareOk[] declare = declareQueues(channel, queue);
虽然此调用卡住了，但我看到队列已声明（通过控制台检查）。此外，随后的 send 调用不会调用 returnedMessage，因为第一个 returnedMessage 调用可能没有 return还没有。
我这里做错了什么？在return回调中声明queue/bindings是否正确？
任何帮助将不胜感激。谢谢。
下面是我的 ReturnCallback：
public class MyReturnCallback implements ReturnCallback {
// constructor, member initialization goes here
@Override
public void returnedMessage(Message message, int replyCode,
String replyText, String exchangeName, String routingKey) {
if (replyCode == 312) {
if (this.exchangeName.equals(exchangeName) && this.routingKey.equals(routingKey)) {
RabbitAdmin admin = new RabbitAdmin(connectionFactory);
Exchange exchange = new DirectExchange(exchangeName, true, false);
Queue queue = new Queue(queueName, true, false, true);
admin.declareQueue(queue);
Binding binding = BindingBuilder.bind(queue).to((DirectExchange)exchange).with(routingKey);
admin.declareBinding(binding);
if (null != binding) {
RabbitTemplate rabbitmqTemplate = new RabbitTemplate(connectionFactory);
logger.debug("Sending to [exchange:" + exchange.getName() + ", routing-key:" + routingKey + "]:" + message.toString());
rabbitmqTemplate.send(exchangeName, routingKey, message);
}
}
}
}
}
我的测试制作人是这样的：
public class TestProducer {
// constructor, member initialization goes here
void initialize()
rabbitAdmin = new RabbitAdmin(connectionFactory);
rabbitTemplate = new RabbitTemplate(connectionFactory);
rabbitTemplate.setExchange(exchangeName);
rabbitTemplate.setMessageConverter(messageConverter);
rabbitTemplate.setRoutingKey(routingKey);
rabbitTemplate.setMandatory(true);
rabbitTemplate.setReturnCallback(new RabbitReturnCallback());
Exchange exchange = new DirectExchange(exchangeName, true, false);
rabbitAdmin.declareExchange(exchange);
Queue queue = new Queue(queueName, true, false, true);
rabbitAdmin.declareQueue(queue);
Binding binding = BindingBuilder.bind(queue).to((DirectExchange)exchange).with(routingKey);
rabbitAdmin.declareBinding(binding);
}
void send() {
rabbitTemplate.convertAndSend(message);
}
}
ConnectionFactory bean 是：
<rabbit:connection-factory id="rabbitmqConnectionFactory"
host="${rabbitmq.host:localhost}"
port="${rabbitmq.port:5672}"
username="${rabbitmq.username}"
password="${rabbitmq.password}"
virtual-host="${rabbitmq.vhost:/}"
cache-mode="CHANNEL"
channel-cache-size="${rabbitmq.channel-cache-size:25}"
publisher-returns="true"/>
附上调试日志以供参考：
2016-10-04 17:58:58,881 [main] INFO CachingConnectionFactory:291 - Created new connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/]
2016-10-04 17:58:58,883 [main] DEBUG RabbitAdmin:399 - Initializing declarations
2016-10-04 17:58:58,883 [main] DEBUG DefaultListableBeanFactory:250 - Returning cached instance of singleton bean 'org.springframework.context.annotation.ConfigurationClassPostProcessor.importRegistry'
2016-10-04 17:58:58,935 [main] DEBUG CachingConnectionFactory:453 - Creating cached Rabbit Channel from PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1)
2016-10-04 17:58:58,975 [main] DEBUG PublisherCallbackChannelImpl:694 - Added listener org.springframework.amqp.rabbit.core.RabbitTemplate@67f639d3
2016-10-04 17:58:58,976 [main] DEBUG RabbitTemplate:1451 - Added pending confirms for Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/] to map, size now 1
2016-10-04 17:58:58,976 [main] DEBUG RabbitTemplate:1296 - Executing callback on RabbitMQ Channel: Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/]
2016-10-04 17:58:58,979 [main] TRACE CachingConnectionFactory:906 - Returning cached Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1)
2016-10-04 17:58:58,979 [main] DEBUG RabbitAdmin:460 - Declarations finished
2016-10-04 17:58:58,980 [main] TRACE CachingConnectionFactory:402 - Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/] retrieved from cache
2016-10-04 17:58:58,981 [main] TRACE CachingConnectionFactory:439 - Found cached Rabbit Channel: Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/]
2016-10-04 17:58:58,981 [main] DEBUG PublisherCallbackChannelImpl:694 - Added listener org.springframework.amqp.rabbit.core.RabbitTemplate@82de64a
2016-10-04 17:58:58,982 [main] DEBUG RabbitTemplate:1451 - Added pending confirms for Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/] to map, size now 1
2016-10-04 17:58:58,982 [main] DEBUG RabbitTemplate:1296 - Executing callback on RabbitMQ Channel: Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/]
2016-10-04 17:58:58,982 [main] DEBUG RabbitAdmin:487 - declaring Exchange 'myexchange'
2016-10-04 17:58:59,006 [main] TRACE CachingConnectionFactory:906 - Returning cached Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1)
2016-10-04 17:58:59,007 [main] INFO TestProducer:59 - Declared/Declare-confirmed for direct exchange: myexchange
2016-10-04 17:58:59,009 [main] DEBUG TestProducer:74 - Sending to [exchange:myexchange, routing-key:mykey]:[testpayload]
2016-10-04 17:58:59,090 [main] TRACE CachingConnectionFactory:402 - Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/] retrieved from cache
2016-10-04 17:58:59,091 [main] TRACE CachingConnectionFactory:439 - Found cached Rabbit Channel: Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/]
2016-10-04 17:58:59,091 [main] DEBUG PublisherCallbackChannelImpl:694 - Added listener org.springframework.amqp.rabbit.core.RabbitTemplate@793f29ff
2016-10-04 17:58:59,091 [main] DEBUG RabbitTemplate:1451 - Added pending confirms for Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/] to map, size now 1
2016-10-04 17:58:59,091 [main] DEBUG RabbitTemplate:1296 - Executing callback on RabbitMQ Channel: Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/]
2016-10-04 17:58:59,098 [main] DEBUG RabbitTemplate:1325 - Publishing message on exchange [myexchange], routingKey = [mykey]
2016-10-04 17:58:59,104 [main] TRACE CachingConnectionFactory:906 - Returning cached Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1)
2016-10-04 17:58:59,134 [AMQP Connection ip-address:5672] DEBUG TestProducer:103 - returnedMessage, replyCode: 312, replyText: NO_ROUTE
2016-10-04 17:58:59,135 [AMQP Connection ip-address:5672] TRACE CachingConnectionFactory:402 - Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/] retrieved from cache
2016-10-04 17:58:59,136 [AMQP Connection ip-address:5672] TRACE CachingConnectionFactory:439 - Found cached Rabbit Channel: Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/]
2016-10-04 17:58:59,163 [AMQP Connection ip-address:5672] DEBUG PublisherCallbackChannelImpl:694 - Added listener org.springframework.amqp.rabbit.core.RabbitTemplate@7ec6c641
2016-10-04 17:58:59,163 [AMQP Connection ip-address:5672] DEBUG RabbitTemplate:1451 - Added pending confirms for Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/] to map, size now 1
2016-10-04 17:58:59,163 [AMQP Connection ip-address:5672] DEBUG RabbitTemplate:1296 - Executing callback on RabbitMQ Channel: Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/]
2016-10-04 17:58:59,164 [AMQP Connection ip-address:5672] DEBUG RabbitAdmin:515 - declaring Queue 'myqueue'
2016-10-04 17:59:29,104 [main] DEBUG TestProducer:74 - Sending to [exchange:myexchange, routing-key:mykey]:[testpayload]
Nothing happens after this.
有趣的问题 - 由于通道在初始发送后放回缓存中，当 return 在该通道上传送时，回调中的发送获得相同的通道，这会导致内部死锁通道 - 在我们仍在处理 return.
时进行声明
我们不能真正延迟将频道放回缓存中，直到我们得到 return，因为我们不知道我们是否会得到 return。
我会考虑是否有任何方法可以检测并避免这种情况，但与此同时，对您来说最安全的做法是处理声明并在不同的线程上重新发布...
private final Executor executor = Executors.newCachedThreadPool();
@Override
public void returnedMessage(Message message, int replyCode, String replyText, String exchangeName,
String routingKey) {
if (replyCode == 312) {
executor.execute(() -> {
RabbitAdmin admin = new RabbitAdmin(connectionFactory);
Exchange exchange = new DirectExchange(exchangeName, true, false);
Queue queue = new Queue("foo", true, false, true);
admin.declareQueue(queue);
Binding binding = BindingBuilder.bind(queue).to((DirectExchange) exchange).with(routingKey);
admin.declareBinding(binding);
if (null != binding) {
RabbitTemplate rabbitmqTemplate = new RabbitTemplate(connectionFactory);
System.out.println("Sending to [exchange:" + exchange.getName() + ", routing-key:" + routingKey
+ "]:" + message.toString());
rabbitmqTemplate.send(exchangeName, routingKey, message);
}
});
}
}
如果没有路由可用，我正在尝试使用发布者 return 的回调来声明队列和绑定，以便不会再次丢弃消息。 这是因为我的队列是自动删除的，如果我的消费者宕机就会被删除。
但是 ReturnCallback 线程卡在 returnedMessage() 中 admin.declareQueue（队列）。
在进一步调试时，我发现它卡在 RabbitAdmin.declareQueue() 中： DeclareOk[] declare = declareQueues(channel, queue);
虽然此调用卡住了，但我看到队列已声明（通过控制台检查）。此外，随后的 send 调用不会调用 returnedMessage，因为第一个 returnedMessage 调用可能没有 return还没有。
我这里做错了什么？在return回调中声明queue/bindings是否正确？
任何帮助将不胜感激。谢谢。
下面是我的 ReturnCallback：
public class MyReturnCallback implements ReturnCallback {
// constructor, member initialization goes here
@Override
public void returnedMessage(Message message, int replyCode,
String replyText, String exchangeName, String routingKey) {
if (replyCode == 312) {
if (this.exchangeName.equals(exchangeName) && this.routingKey.equals(routingKey)) {
RabbitAdmin admin = new RabbitAdmin(connectionFactory);
Exchange exchange = new DirectExchange(exchangeName, true, false);
Queue queue = new Queue(queueName, true, false, true);
admin.declareQueue(queue);
Binding binding = BindingBuilder.bind(queue).to((DirectExchange)exchange).with(routingKey);
admin.declareBinding(binding);
if (null != binding) {
RabbitTemplate rabbitmqTemplate = new RabbitTemplate(connectionFactory);
logger.debug("Sending to [exchange:" + exchange.getName() + ", routing-key:" + routingKey + "]:" + message.toString());
rabbitmqTemplate.send(exchangeName, routingKey, message);
}
}
}
}
}
我的测试制作人是这样的：
public class TestProducer {
// constructor, member initialization goes here
void initialize()
rabbitAdmin = new RabbitAdmin(connectionFactory);
rabbitTemplate = new RabbitTemplate(connectionFactory);
rabbitTemplate.setExchange(exchangeName);
rabbitTemplate.setMessageConverter(messageConverter);
rabbitTemplate.setRoutingKey(routingKey);
rabbitTemplate.setMandatory(true);
rabbitTemplate.setReturnCallback(new RabbitReturnCallback());
Exchange exchange = new DirectExchange(exchangeName, true, false);
rabbitAdmin.declareExchange(exchange);
Queue queue = new Queue(queueName, true, false, true);
rabbitAdmin.declareQueue(queue);
Binding binding = BindingBuilder.bind(queue).to((DirectExchange)exchange).with(routingKey);
rabbitAdmin.declareBinding(binding);
}
void send() {
rabbitTemplate.convertAndSend(message);
}
}
ConnectionFactory bean 是：
<rabbit:connection-factory id="rabbitmqConnectionFactory"
host="${rabbitmq.host:localhost}"
port="${rabbitmq.port:5672}"
username="${rabbitmq.username}"
password="${rabbitmq.password}"
virtual-host="${rabbitmq.vhost:/}"
cache-mode="CHANNEL"
channel-cache-size="${rabbitmq.channel-cache-size:25}"
publisher-returns="true"/>
附上调试日志以供参考：
2016-10-04 17:58:58,881 [main] INFO CachingConnectionFactory:291 - Created new connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/]
2016-10-04 17:58:58,883 [main] DEBUG RabbitAdmin:399 - Initializing declarations
2016-10-04 17:58:58,883 [main] DEBUG DefaultListableBeanFactory:250 - Returning cached instance of singleton bean 'org.springframework.context.annotation.ConfigurationClassPostProcessor.importRegistry'
2016-10-04 17:58:58,935 [main] DEBUG CachingConnectionFactory:453 - Creating cached Rabbit Channel from PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1)
2016-10-04 17:58:58,975 [main] DEBUG PublisherCallbackChannelImpl:694 - Added listener org.springframework.amqp.rabbit.core.RabbitTemplate@67f639d3
2016-10-04 17:58:58,976 [main] DEBUG RabbitTemplate:1451 - Added pending confirms for Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/] to map, size now 1
2016-10-04 17:58:58,976 [main] DEBUG RabbitTemplate:1296 - Executing callback on RabbitMQ Channel: Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/]
2016-10-04 17:58:58,979 [main] TRACE CachingConnectionFactory:906 - Returning cached Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1)
2016-10-04 17:58:58,979 [main] DEBUG RabbitAdmin:460 - Declarations finished
2016-10-04 17:58:58,980 [main] TRACE CachingConnectionFactory:402 - Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/] retrieved from cache
2016-10-04 17:58:58,981 [main] TRACE CachingConnectionFactory:439 - Found cached Rabbit Channel: Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/]
2016-10-04 17:58:58,981 [main] DEBUG PublisherCallbackChannelImpl:694 - Added listener org.springframework.amqp.rabbit.core.RabbitTemplate@82de64a
2016-10-04 17:58:58,982 [main] DEBUG RabbitTemplate:1451 - Added pending confirms for Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/] to map, size now 1
2016-10-04 17:58:58,982 [main] DEBUG RabbitTemplate:1296 - Executing callback on RabbitMQ Channel: Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/]
2016-10-04 17:58:58,982 [main] DEBUG RabbitAdmin:487 - declaring Exchange 'myexchange'
2016-10-04 17:58:59,006 [main] TRACE CachingConnectionFactory:906 - Returning cached Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1)
2016-10-04 17:58:59,007 [main] INFO TestProducer:59 - Declared/Declare-confirmed for direct exchange: myexchange
2016-10-04 17:58:59,009 [main] DEBUG TestProducer:74 - Sending to [exchange:myexchange, routing-key:mykey]:[testpayload]
2016-10-04 17:58:59,090 [main] TRACE CachingConnectionFactory:402 - Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/] retrieved from cache
2016-10-04 17:58:59,091 [main] TRACE CachingConnectionFactory:439 - Found cached Rabbit Channel: Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/]
2016-10-04 17:58:59,091 [main] DEBUG PublisherCallbackChannelImpl:694 - Added listener org.springframework.amqp.rabbit.core.RabbitTemplate@793f29ff
2016-10-04 17:58:59,091 [main] DEBUG RabbitTemplate:1451 - Added pending confirms for Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/] to map, size now 1
2016-10-04 17:58:59,091 [main] DEBUG RabbitTemplate:1296 - Executing callback on RabbitMQ Channel: Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/]
2016-10-04 17:58:59,098 [main] DEBUG RabbitTemplate:1325 - Publishing message on exchange [myexchange], routingKey = [mykey]
2016-10-04 17:58:59,104 [main] TRACE CachingConnectionFactory:906 - Returning cached Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1)
2016-10-04 17:58:59,134 [AMQP Connection ip-address:5672] DEBUG TestProducer:103 - returnedMessage, replyCode: 312, replyText: NO_ROUTE
2016-10-04 17:58:59,135 [AMQP Connection ip-address:5672] TRACE CachingConnectionFactory:402 - Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/] retrieved from cache
2016-10-04 17:58:59,136 [AMQP Connection ip-address:5672] TRACE CachingConnectionFactory:439 - Found cached Rabbit Channel: Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/]
2016-10-04 17:58:59,163 [AMQP Connection ip-address:5672] DEBUG PublisherCallbackChannelImpl:694 - Added listener org.springframework.amqp.rabbit.core.RabbitTemplate@7ec6c641
2016-10-04 17:58:59,163 [AMQP Connection ip-address:5672] DEBUG RabbitTemplate:1451 - Added pending confirms for Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/] to map, size now 1
2016-10-04 17:58:59,163 [AMQP Connection ip-address:5672] DEBUG RabbitTemplate:1296 - Executing callback on RabbitMQ Channel: Cached Rabbit Channel: PublisherCallbackChannelImpl: AMQChannel(amqp://test@ip-address:5672/,1), conn: Proxy@bae7dc0 Shared Rabbit Connection: SimpleConnection@4f2b503c [delegate=amqp://test@ip-address:5672/]
2016-10-04 17:58:59,164 [AMQP Connection ip-address:5672] DEBUG RabbitAdmin:515 - declaring Queue 'myqueue'
2016-10-04 17:59:29,104 [main] DEBUG TestProducer:74 - Sending to [exchange:myexchange, routing-key:mykey]:[testpayload]
Nothing happens after this.
有趣的问题 - 由于通道在初始发送后放回缓存中，当 return 在该通道上传送时，回调中的发送获得相同的通道，这会导致内部死锁通道 - 在我们仍在处理 return.
时进行声明我们不能真正延迟将频道放回缓存中，直到我们得到 return，因为我们不知道我们是否会得到 return。
我会考虑是否有任何方法可以检测并避免这种情况，但与此同时，对您来说最安全的做法是处理声明并在不同的线程上重新发布...
private final Executor executor = Executors.newCachedThreadPool();
@Override
public void returnedMessage(Message message, int replyCode, String replyText, String exchangeName,
String routingKey) {
if (replyCode == 312) {
executor.execute(() -> {
RabbitAdmin admin = new RabbitAdmin(connectionFactory);
Exchange exchange = new DirectExchange(exchangeName, true, false);
Queue queue = new Queue("foo", true, false, true);
admin.declareQueue(queue);
Binding binding = BindingBuilder.bind(queue).to((DirectExchange) exchange).with(routingKey);
admin.declareBinding(binding);
if (null != binding) {
RabbitTemplate rabbitmqTemplate = new RabbitTemplate(connectionFactory);
System.out.println("Sending to [exchange:" + exchange.getName() + ", routing-key:" + routingKey
+ "]:" + message.toString());
rabbitmqTemplate.send(exchangeName, routingKey, message);
}
});
}
}