RabbitAdmin功能
RabbitAdmin類用來管理RabbitMQ;
創建方法:
ConnectionFactory connectionFactory = new CachingConnectionFactory(); RabbitAdmin rabbitAdmin = new RabbitAdmin(connectionFactory);
- declareExchange:創建交換機
- deleteExchange:刪除交換機
- declareQueue:創建隊列
- deleteQueue:刪除隊列
- purgeQueue:清空隊列
- declareBinding:新建綁定關系
- removeBinding:刪除綁定關系
- getQueueProperties:查詢隊列屬性
CachingConnectionFactory是Spring AMQP下一個連接工廠,適合SpringBoot的深度整合的連接工廠;
從構造方法出發
org.springframework.amqp.rabbit.connection.CachingConnectionFactory#CachingConnectionFactory()
最終會調用這個有參構造方法
org.springframework.amqp.rabbit.connection.CachingConnectionFactory#CachingConnectionFactory(java.lang.String, int)
CachingConnectionFactory最終會調用RabbitMQ的原生API,對RabbitMQ Client包下的ConnectionFactory的包裝;
對於下面的這個寫法,這個ConnectionFactory是Spring AMQP包下的,它繼承了AbstractConnectionFactory,而AbstractConnectionFactory實現了Spring AMQP包下的ConnectionFactory;如下圖;
ConnectionFactory connectionFactory = new CachingConnectionFactory();
org.springframework.amqp.core.Exchange實現類,每種實現對應一種交換機類型,如下圖;
org.springframework.amqp.core.Queue#Queue(java.lang.String) 對應的參數,如下圖;
org.springframework.amqp.core.Binding#Binding 對應的參數,如下圖;
org.springframework.amqp.rabbit.core.RabbitAdmin#declareExchange RabbitAdmin使用該方法將交換機進行綁定,使用了RabbitTemplate對RabbitMQ Client包進行了封裝;
最終在org.springframework.amqp.rabbit.core.RabbitAdmin#declareExchanges會有調用RabbitMQ Client的原生API,如下圖;
測試代碼
@Slf4j @Configuration public class RabbitConfig { @PostConstruct public void initRabbit() { CachingConnectionFactory connectionFactory = new CachingConnectionFactory(); connectionFactory.setHost("192.168.211.135"); connectionFactory.setPort(5672); connectionFactory.setVirtualHost("/dev"); connectionFactory.setUsername("admin"); connectionFactory.setPassword("password"); RabbitAdmin rabbitAdmin = new RabbitAdmin(connectionFactory); Exchange exchange = new TopicExchange("exchange.order"); // 創建交換機 rabbitAdmin.declareExchange(exchange); Queue queue = new Queue("queue.order"); // 創建隊列 rabbitAdmin.declareQueue(queue); Binding binding = new Binding( "queue.order", Binding.DestinationType.QUEUE, "exchange.order", "key.order", null ); // 新建綁定關系 rabbitAdmin.declareBinding(binding); } }
服務重啟后,在RabbitMQ的管控台會出現新建的隊列,交換機;
RabbitAdmin聲明式配置
- 將Exchange,Queue,Binding聲明為Bean;
- 再將RabbitAdmin聲明為Bean;
- Exchange,Queue,Binding即可自動創建;
代碼如下:
@Slf4j @Configuration public class RabbitConfig { @Bean public ConnectionFactory connectionFactory() { CachingConnectionFactory connectionFactory = new CachingConnectionFactory(); connectionFactory.setHost("192.168.211.135"); connectionFactory.setPort(5672); connectionFactory.setVirtualHost("/dev"); connectionFactory.setUsername("admin"); connectionFactory.setPassword("password"); // connectionFactory.createConnection(); return connectionFactory; } @Bean public Exchange exchange() { Exchange exchange = new TopicExchange("exchange.order"); return exchange; } @Bean public Queue queue() { Queue queue = new Queue("queue.order"); return queue; } @Bean public Binding binding() { Binding binding = new Binding( "queue.order", Binding.DestinationType.QUEUE, "exchange.order", "key.order", null ); return binding; } @Bean public RabbitAdmin rabbitAdmin(@Autowired ConnectionFactory connectionFactory) { RabbitAdmin rabbitAdmin = new RabbitAdmin(connectionFactory); // 自動創建打開 rabbitAdmin.setAutoStartup(true); return rabbitAdmin; } }
不過@Bean這種注入方式有點懶加載的意思,就是當你注入的Bean沒有被使用時,它是不會被加載的;上面配置的Bean如果沒有在其他地方被使用,這些Bean是不會被加載;
org.springframework.amqp.rabbit.core.RabbitAdmin類中實現了ApplicationContextAware,InitializingBean接口;之前講過ApplicationContextAware是可以獲取Spring容器的上下文,從而可以注入別的組件注入到該對象;InitializingBean是Bean創建后進行初始化的操作,此時是Bean對象已經創建;
在RabbitAdmin實現的InitializingBean接口的afterPropertiesSet方法,有如下一個操作;
org.springframework.amqp.rabbit.connection.CachingConnectionFactory#addConnectionListener
在RabbitMQ進行連接的時候會回調添加的listener;
在RabbitAdmin實現的afterPropertiesSet方法,最終會調用一個initialize方法;
org.springframework.amqp.rabbit.core.RabbitAdmin#initialize
通過applicationContext獲取到所有的Exchange,Queue,Binding類型的Bean;
最終會創建相應的 Exchange,Queue,Binding;
當ConnectionFactory執行createConnection,相應的 Exchange,Queue,Binding通過Spring容器被創建;
connectionFactory.createConnection();
RabbitTemplate
- RabbitTemplate與RestTemplate類似,使用了模板方法設計模式;
- RabbitTemplate提供了豐富的功能,方便消息收發;
- RabbitTemplate可以顯式傳入配置也可以隱式聲明配置;
顯式傳入配置,使用無參構造方法是不能拿到連接工廠的;
顯式傳入配置時,應選用帶有參數的構造方法;
顯式配置如下:
@Bean public ConnectionFactory connectionFactory() { CachingConnectionFactory connectionFactory = new CachingConnectionFactory(); connectionFactory.setHost("192.168.211.135"); connectionFactory.setPort(5672); connectionFactory.setVirtualHost("/dev"); connectionFactory.setUsername("admin"); connectionFactory.setPassword("password"); connectionFactory.createConnection(); return connectionFactory; } @Bean public RabbitTemplate rabbitTemplate(ConnectionFactory connectionFactory) { RabbitTemplate rabbitTemplate = new RabbitTemplate(connectionFactory); return rabbitTemplate; }
聲明Exchange,Queue,Binding;
@Bean public Exchange exchange() { Exchange exchange = new TopicExchange("exchange.order"); return exchange; } @Bean public Queue queue() { Queue queue = new Queue("queue.order"); return queue; } @Bean public Binding binding() { Binding binding = new Binding( "queue.order", Binding.DestinationType.QUEUE, "exchange.order", "key.order", null ); return binding; }
RabbitTemplate中發送消息的方法有send和convertAndSend;
關於send方法的使用如下:
send方法使用需要將要發送的消息轉換為字節流;
Message message = new Message("test".getBytes(), null); rabbitTemplate.send("exchange.order", "key.order", message);
上面代碼運行后會報錯:
根據異常追蹤到拋NPE的位置:
將上面的Message創建修改如下,消息能正常發出;
Message message = new Message("test".getBytes(), new MessageProperties());
關於convertAndSend方法使用如下:
rabbitTemplate.convertAndSend("exchange.order", "key.order", "test2");
org.springframework.amqp.rabbit.core.RabbitTemplate#send(java.lang.String, java.lang.String, org.springframework.amqp.core.Message, org.springframework.amqp.rabbit.connection.CorrelationData)
execute方法里面傳入了一個lambda對象,里面的channel指的是RabbitMQ Client的Channel對象;
org.springframework.amqp.rabbit.core.RabbitTemplate#doSend最終會調用sendToRabbit方法;
org.springframework.amqp.rabbit.core.RabbitTemplate#sendToRabbit
而在convertAndSend方法中不需要對消息內容進行字節流,因為在convertAndSend方法最終會調send方法,在send方法傳入的消息內容的參數做了轉換;
配置發送端確認和消息返回
confirmCallback為生產者投遞消息后,如果Broker收到消息后,會給生產者一個ACK;生產者通過ACK,可以確認這條消息是否正常發送到Broker,即發送端確認機制;
returnCallback為交換機到隊列不成功,返回給消息生產者,觸發returnCallback,即消息返回機制;
@Bean public RabbitTemplate rabbitTemplate(ConnectionFactory connectionFactory) { RabbitTemplate rabbitTemplate = new RabbitTemplate(connectionFactory); // 換機處理消息到路由失敗,則會返回給生產者 rabbitTemplate.setMandatory(true); // 交換機到隊列不成功,返回給消息生產者,觸發returnCallback rabbitTemplate.setReturnCallback(new RabbitTemplate.ReturnCallback() { @Override public void returnedMessage(Message message, int replyCode, String replyText, String exchange, String routingKey) { log.info("message:{} replyCode:{}, replyText:{}, exchange:{}, routingKey:{}", message, replyCode, replyText, exchange, routingKey); } }); // 生產者投遞消息后,如果Broker收到消息后,會給生產者一個ACK。生產者通過ACK,可以確認這條消息是否正常發送到Broker rabbitTemplate.setConfirmCallback(new RabbitTemplate.ConfirmCallback() { @Override public void confirm(CorrelationData correlationData, boolean ack, String cause) { log.info("correlationData:{}, ack:{}, cause:{}", correlationData, ack, cause); } }); return rabbitTemplate; }
配置完后,服務重啟,發送消息,confirmCallback並沒有回調;
主要原因是這里用的ConnectionFactory是自定義配置注入的,不是Spring Boot配置注入的,如果需要使用Spring Boot配置注入,需要application.properties配置文件配置RabbitMQ的連接信息;
RabbitTemplate類有一個publisherConfirms的成員屬性;
org.springframework.amqp.rabbit.core.RabbitTemplate#publisherConfirms,通過connectionFactory.isPublisherConfirms()控制publisherConfirms;
在ConnectionFactory配置添加setPublisherConfirms,不過該方法從Spring Boot2.2已棄用,需要使用setPublisherConfirmType方法;
setPublisherConfirms對應application.properteise中確認消息發送成功,通過實現ConfirmCallBack接口,消息發送到交換器Exchange后觸發回調的配置是:
spring.rabbitmq.publisher-confirms=true
SIMPLE值發布消息成功到交換器后會觸發回調方法,但是無法得知是被確認的是哪條消息;
NONE值是禁用發布確認模式,是默認值;
CORRELATED值也是發布消息成功到交換器后會觸發回調方法,發送的消息使用CorrelationData進行相關聯;
配置成SIMPLE
connectionFactory.setPublisherConfirmType(CachingConnectionFactory.ConfirmType.SIMPLE); connectionFactory.setPublisherReturns(true);
效果如下:
配置成CORRELATED
connectionFactory.setPublisherConfirmType(CachingConnectionFactory.ConfirmType.CORRELATED); connectionFactory.setPublisherReturns(true);
發送方修改如下:
CorrelationData correlationData = new CorrelationData(); correlationData.setId("test2_Id"); rabbitTemplate.convertAndSend("exchange.order", "key.order", "test2", correlationData);
執行如下:
SimpleMessageListenerContainer簡單消息監聽容器
- 設置同時監聽多個隊列,自動啟動,自動配置RabbitMQ
- 設置消費者數量
- 設置消息確認模式,是否重回隊列,異常捕獲
- 設置是否獨占,其他線程消費屬性等
- 設置具體的監聽器,消息轉換器等
- 支持動態設置,運行中修改監聽器配置
使用如下:
@Bean public SimpleMessageListenerContainer simpleMessageListenerContainer(ConnectionFactory connectionFactory) { SimpleMessageListenerContainer container = new SimpleMessageListenerContainer(connectionFactory); // 設置監聽的隊列 container.setQueueNames("queue.order"); // 設置並發的消費者 container.setConcurrentConsumers(3); // 設置最大並發的消費者 container.setMaxConcurrentConsumers(3); // 設置確認方式 container.setAcknowledgeMode(AcknowledgeMode.MANUAL); // 設置消息監聽回調 container.setMessageListener(new ChannelAwareMessageListener() { @Override public void onMessage(Message message, Channel channel) throws Exception { log.info("message:{}", message); channel.basicAck(message.getMessageProperties().getDeliveryTag(), false); } }); // 現在每次只允許一條消息消費 container.setPrefetchCount(1); return container; }
帶有Channel的MessageListener擴展接口,用於手動確認;
執行如下:
message:(Body:'test2' MessageProperties [headers={spring_listener_return_correlation=b6ba6114-27c4-4c9b-ac4d-e3053ecf8762, spring_returned_message_correlation=test2_Id}, contentType=text/plain, contentEncoding=UTF-8, contentLength=0, receivedDeliveryMode=PERSISTENT, priority=0, redelivered=false, receivedExchange=exchange.order, receivedRoutingKey=key.order, deliveryTag=2, consumerTag=amq.ctag-HIhcGJg7Q6OdAV-q26zbnQ, consumerQueue=queue.order])
之前在代碼中設置SimpleMessageListenerContainer最大並發的消費者為3個,每次只允許消費一條消息,可以從管控台看出,配置已生效;
SimpleMessageListenerContainer類的繼承樹如下
org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer實現了MessageListenerContainer;
MessageListenerContainer接口的繼承樹如下:
MessageListenerContainer最終繼承了LifeCycle的接口,LifeCycle接口是Spring框架的接口,用於定義注入Spring中的Bean啟動/停止生命周期控制方法的通用接口,當Bean啟動交給Spring容器管理的時候,該Bean中的start方法會被回調;
org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer#start
AbstractMessageListenerContainer#start會調到實現類的doStart方法;
org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer#doStart
調用initializeConsumers方法執行初始化消費者;initializeConsumers方法里面會調用createBlockingQueueConsumer方法創建BlockingQueueConsumer對象;
關於org.springframework.amqp.rabbit.listener.BlockingQueueConsumer對象,如下:
BlockingQueueConsumer這個類Spring AMQP包下RabbitMQ專門的消費者,封裝了消息broker的連接,並有自己的生命周期;
之后回到org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer#doStart方法;
將與RabbitMQ的Channel通信的BlockingQueueConsumer對象的集合封裝到AsyncMessageProcessingConsumer對象中,而AsyncMessageProcessingConsumer對象又實現了Runnable接口,getTaskExecutor方法獲取到的是Spring封裝的SimpleAsyncTaskExecutor類型的線程池,該線程池是來一個任務創建一個線程,比較適合短期多任務,通過getTaskExecutor方法獲取的線程執行AsyncMessageProcessingConsumer對象的run方法;正常情況下run方法會執行initialize方法;
org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.AsyncMessageProcessingConsumer#initialize
最終調用BlockingQueueConsumer#start方法;start方法里面會調用setQosAndreateConsumers方法,該方法用於創建消費者和設置消費者最大能消費的消息數量;
org.springframework.amqp.rabbit.listener.BlockingQueueConsumer#setQosAndreateConsumers
最終會調用consumeFromQueue方法;
org.springframework.amqp.rabbit.listener.BlockingQueueConsumer#consumeFromQueue
該方法啟動一個消費者,但是channel調用basicConsume方法傳入用於處理接收RabbitMQ消息時的回調Consumer是內部的InternalConsumer對象;
當接收到消息時, InternalConsumer會回調handleDelivery方法,將消息放入到隊列中;
之后會循環執行AsyncMessageProcessingConsumer#mainLoop;
receiveAndExecute方法會調用SimpleMessageListenerContainer#receiveAndExecute,SimpleMessageListenerContainer#receiveAndExecute會調用SimpleMessageListenerContainer#doReceiveAndExecute方法,doReceiveAndExecute方法最終會調用BlockingQueueConsumer#nextMessage(long)方法,消息會從隊列里取出,消息接收通過basicConsumer接收,消費的消息是從mainLoop方法中取,當接收到消息時會將消息存到本地隊列,等待消息消費;
取出的消息是如何觸發onMessage方法?
SimpleMessageListenerContainer#doReceiveAndExecute如果沒有打開consumerBatchEnabled,則執行下面的executeListener方法,executeListener調用doExecuteListener方法,doExecuteListener會調用invokeListener方法;
而invokerListener是函數式接口,不是方法體;
invokerListenr方法的實現在proxy對象;
org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer#actualInvokeListener
該方法是先判斷listener的類型,之后執行doInvokerListener方法,在doInvokerListener方法中會回調MessageListener的onMessage方法;
SimpleMessageListenerContainer調用鏈大致如下:
MessageListenerAdapter 消息監聽適配器
使用:
- 實現handleMessage方法
- 自定義隊列名->方法名的映射關系
使用如下:
手動注入SimpleMessageListenerContainer
@Bean public SimpleMessageListenerContainer simpleMessageListenerContainer(ConnectionFactory connectionFactory) { SimpleMessageListenerContainer container = new SimpleMessageListenerContainer(connectionFactory); // 設置監聽的隊列 container.setQueueNames("queue.order"); // 設置並發的消費者 container.setConcurrentConsumers(3); // 設置最大並發的消費者 container.setMaxConcurrentConsumers(3); // 設置確認方式 container.setAcknowledgeMode(AcknowledgeMode.MANUAL); // 設置消息監聽回調 // container.setMessageListener(new ChannelAwareMessageListener() { // @Override // public void onMessage(Message message, Channel channel) throws Exception { // log.info("message:{}", message); // channel.basicAck(message.getMessageProperties().getDeliveryTag(), false); // } // }); MessageListenerAdapter listenerAdapter = new MessageListenerAdapter(); // 設置消息監聽回調調用orderService listenerAdapter.setDelegate(orderService); container.setMessageListener(listenerAdapter); // 現在每次只允許一條消息消費 container.setPrefetchCount(1); return container; }
注入OrderService
public interface OrderService { void handleMessage(String messageBody) throws IOException; }
@Slf4j @Service public class OrderServiceImpl implements OrderService { @Override public void handleMessage(String messageBody) throws IOException { log.info("orderService handleMessage:{}", messageBody); } }
當有監聽到消息到達時,OrderServiceImpl#handleMessage方法會被調用;
執行如下:
為何handleMessage方法會被調用?
MessageListenerAdapter的繼承樹如下:
MessageListenerAdapter實現了MessageListener接口,當有消息到達時,MessageListenerAdapter#onMessage方法會被觸發;
org.springframework.amqp.rabbit.listener.adapter.MessageListenerAdapter#onMessage
首先先拿到delegateListener對象,判斷delegateListener是否為ChannelAwareMessageListener或MessageListener類型,如果delegateListener是那些類型,delegateListener就調用onMessage方法;
delegate對象在調用doSetDelegate方法時賦值;
MessageListenerAdapter#onMessage獲取到消息處理的方法名,之后調用該方法;
org.springframework.amqp.rabbit.listener.adapter.MessageListenerAdapter#getListenerMethodName
默認情況下,queueOrTagToMethodName是沒有設置的,因此獲取的是默認的值;
不同的隊列如何設置調用不同的消息處理?
將上面的代碼修改如下:
MessageListenerAdapter listenerAdapter = new MessageListenerAdapter(orderService); HashMap<String, String> methodMap = new HashMap<>(8); methodMap.put("queue.order1", "handleMessage1"); methodMap.put("queue.order2", "handleMessage2"); listenerAdapter.setQueueOrTagToMethodName(methodMap); container.setMessageListener(listenerAdapter);
MessageConverter 消息轉換器
RabbitMQ Client原生的消息收發是通過byte[]作為消息體的,MessageConverter用來在收發消息時自動轉換消息;
Jackson2JsonMessageConverter
Jackson轉換Json消息格式,最常用的MessageConverter,用來轉換Json格式消息;
配合ClassMapper可以直接轉換為POJO對象;
自定義MessageConverter
實現MessageConverter接口;
重寫toMessage,fromMessage方法;
使用如下:
實體類OrderDTO
@Data public class OrderDTO implements Serializable { private String orderId; private Date createDate; private BigDecimal totalAmount; private BigDecimal payAmount; private String payType; }
發送消息:
ObjectMapper objectMapper = new ObjectMapper(); String jsonStr = objectMapper.writeValueAsString(orderDTO); Message message = new Message(jsonStr.getBytes(), new MessageProperties()); CorrelationData correlationData = new CorrelationData(); correlationData.setId(uuid); rabbitTemplate.convertAndSend("exchange.order", "key.order", message, correlationData);
SimpleMessageListenerContainer配置修改:
設置轉換消息的類型
MessageListenerAdapter listenerAdapter = new MessageListenerAdapter(orderService); HashMap<String, String> methodMap = new HashMap<>(8); methodMap.put("queue.order", "handleMessage"); listenerAdapter.setQueueOrTagToMethodName(methodMap); Jackson2JsonMessageConverter converter = new Jackson2JsonMessageConverter(); converter.setClassMapper(new ClassMapper() { @Override public void fromClass(Class<?> clazz, MessageProperties properties) { } /** * 設置轉換消息的類型 * @param properties * @return */ @Override public Class<?> toClass(MessageProperties properties) { return OrderDTO.class; } }); listenerAdapter.setMessageConverter(converter);
執行如下:
分析:
org.springframework.amqp.rabbit.listener.adapter.MessageListenerAdapter#onMessage
這里獲取轉換后的消息;
org.springframework.amqp.rabbit.listener.adapter.AbstractAdaptableMessageListener#extractMessage
獲取往MessageListenerAdapter設置的消息轉換器,之后調用fromMessage方法轉換消息;
上面測試代碼設置的轉換器是Jackson2JsonMessageConverter,最終調用AbstractJackson2MessageConverter#fromMessage(org.springframework.amqp.core.Message, java.lang.Object);
轉換器沒有設置alwaysConvertToInferredType和javaTypeMapper,並且classMapper不為空,則執行下面的邏輯;
toClass調用的是上面測試代碼的里面的;
convertBytesToObject方法最終是調用Jackson進行Json轉換;
@RabbitListener注解
@RabbitListener是一個組合注解,可以嵌套以下注解:
@Exchange:自動聲明Exchange
@Queue:自動聲明隊列
@QueueBinding:自動聲明綁定關系
要使用@RabbitListener注解,需要注入RabbitListenerContainerFactory;
@Bean public RabbitListenerContainerFactory rabbitListenerContainerFactory(ConnectionFactory connectionFactory) { SimpleRabbitListenerContainerFactory factory = new SimpleRabbitListenerContainerFactory(); factory.setConnectionFactory(connectionFactory); factory.setAcknowledgeMode(AcknowledgeMode.MANUAL); return factory; }
消息監聽處理類,如下;
使用 @Payload和@Headers注解可以消息中的body(字符串類型)與 headers 信息;
@RabbitHandler用於接收消息處理,下面的寫法是同一個隊列下所有類型的消息都會執行該方法;
@Slf4j @Component @RabbitListener(containerFactory = "rabbitListenerContainerFactory", queues = { "queue.order" }) public class OrderMessageHandler1 { @RabbitHandler(isDefault = true) public void handleOrderQueue(Message message, @Payload String body, Channel channel) throws IOException { long msgTag = message.getMessageProperties().getDeliveryTag(); log.info("body:{}, message:{}, msgTag:{}", body, message, msgTag); // 成功確認,使用此回執方法后,消息會被 rabbitmq broker 刪除 channel.basicAck(msgTag, false); } }
@RabbitListener注解中containerFactory為注入的RabbitListenerContainerFactory類型的bean名,queues為要監聽的隊列的名;
執行如下:
body:{"orderId":"dcfac502-2dc2-4f15-b7e0-352148c1c854","createDate":1624895624124,"totalAmount":null,"payAmount":null,"payType":null}, message:(Body:'[B@4644fcc8(byte[128])' MessageProperties [headers={spring_listener_return_correlation=2089040d-82e1-4f89-877c-7eb532a7c4fa, spring_returned_message_correlation=dcfac502-2dc2-4f15-b7e0-352148c1c854}, contentType=application/octet-stream, contentLength=0, receivedDeliveryMode=PERSISTENT, priority=0, redelivered=false, receivedExchange=exchange.order, receivedRoutingKey=key.order, deliveryTag=1, consumerTag=amq.ctag-msLGsIwV9daq1O0avuXXyQ, consumerQueue=queue.order]), msgTag:1
RabbitListenerContainerFactory的繼承樹如下:
AbstractRabbitListenerContainerFactory#setMessageConverter 設置消息轉換器;
-
-
消息的 content_type 屬性表示消息 body 數據以什么數據格式存儲,接收消息除了使用 Message 對象接收消息(包含消息屬性等信息)之外,還可直接使用對應類型接收消息 body 內容,但若方法參數類型不正確會拋異常:
-
application/octet-stream:二進制字節數組存儲,使用 byte[];
-
application/x-java-serialized-object:java 對象序列化格式存儲,使用 Object、相應類型(反序列化時類型應該同包同名,否者會拋出找不到類異常);
-
text/plain:文本數據類型存儲,使用 String;
-
application/json
@RabbitListener也可以修飾消息處理的方法,如下:
@RabbitListener(containerFactory = "rabbitListenerContainerFactory", queues = { "queue.order" }) public void handleOrderQueue(Message message, @Payload String body, Channel channel) throws IOException { long msgTag = message.getMessageProperties().getDeliveryTag(); log.info("body:{}, message:{}, msgTag:{}", body, message, msgTag); // 成功確認,使用此回執方法后,消息會被 rabbitmq broker 刪除 channel.basicAck(msgTag, false); }
執行如下:
body:{"orderId":"1f4e343e-a26f-4410-9939-102e728e9df1","createDate":1624897186777,"totalAmount":null,"payAmount":null,"payType":null}, message:(Body:'[B@4d1af5df(byte[128])' MessageProperties [headers={spring_listener_return_correlation=a87fbdb8-12e1-4828-bdee-b92c76b910cf, spring_returned_message_correlation=1f4e343e-a26f-4410-9939-102e728e9df1}, contentType=application/octet-stream, contentLength=0, receivedDeliveryMode=PERSISTENT, priority=0, redelivered=false, receivedExchange=exchange.order, receivedRoutingKey=key.order, deliveryTag=1, consumerTag=amq.ctag-2liRtkURbpuuRgV4EGyyZA, consumerQueue=queue.order]), msgTag:1
通過@RabbitListener注解的屬性bindings聲明Binding,如果RabbitMQ中不存在該綁定所需要的Queue、Exchange、RouteKey 則自動創建,若存在則拋出異常,使用如下:
@RabbitListener(containerFactory = "rabbitListenerContainerFactory", admin = "rabbitAdmin", bindings = { @QueueBinding(value = @Queue(name = "queue.order"), exchange = @Exchange(name = "exchange.order", type = ExchangeTypes.TOPIC), key = "key.order") }) public void handleOrderQueue(Message message, @Payload String body, Channel channel) throws IOException { long msgTag = message.getMessageProperties().getDeliveryTag(); log.info("body:{}, message:{}, msgTag:{}", body, message, msgTag); // 成功確認,使用此回執方法后,消息會被 rabbitmq broker 刪除 channel.basicAck(msgTag, false); }
應用啟動后,查看管控台;
執行如下:
body:{"orderId":"97d08e05-588f-4cb0-b551-f5fb32634e96","createDate":1624898825450,"totalAmount":null,"payAmount":null,"payType":null}, message:(Body:'[B@12fea6bb(byte[128])' MessageProperties [headers={spring_listener_return_correlation=0924912e-a6a9-4e08-8196-1355a04e2325, spring_returned_message_correlation=97d08e05-588f-4cb0-b551-f5fb32634e96}, contentType=application/octet-stream, contentLength=0, receivedDeliveryMode=PERSISTENT, priority=0, redelivered=false, receivedExchange=exchange.order, receivedRoutingKey=key.order, deliveryTag=3, consumerTag=amq.ctag-1e3NzsIvhnYRFl295JKOvQ, consumerQueue=queue.order]), msgTag:1
Spring Boot整合RabbitMQ
使用application.properties配置,需要使用Spring Boot配置注入,在application.properties配置文件配置RabbitMQ的連接信息;
連接配置如下:
spring.rabbitmq.host=192.168.211.135 spring.rabbitmq.port=5672 spring.rabbitmq.username=admin spring.rabbitmq.password=password spring.rabbitmq.virtual-host=/dev
- 生產者到交換機
開啟confirmCallback,生產者投遞消息后,如果Broker收到消息后,會給生產者一個ACK;生產者通過ACK,可以確認這條消息是否正常發送到Broker,這種方式是消息可靠性投遞的核心;
spring.rabbitmq.publisher-confirm-type: correlated
Spring Boot2.2之前使用如下配置:
spring.rabbitmq.publisher-confirms=true
- 交換機到隊列
開啟returnCallback配置
spring.rabbitmq.publisher-returns=true
配置交換機投遞到隊列失敗的策略
交換機到隊列不成功,則丟棄消息(默認);交換機到隊列不成功,返回給消息生產者,觸發returnCallback;
#交換機處理消息到路由失敗,則會返回給生產者 spring.rabbitmq.template.mandatory=true
對應的RabbitTemplate配置
template.setMandatory(true);
- RabbitMQ的ACK
-
- 消費者從RabbitMQ收到消息並處理完成后,反饋給RabbitMQ,RabbitMQ收到反饋后才將此消息從隊列中刪除;
- 消費者在處理消息出現了網絡不穩定、服務器異常等現象,那么就不會有ACK反饋,RabbitMQ會認為這個消息沒有正常消費,會將消息重新放入隊列中;
- 只有當消費者正確發送ACK應答,RabbitMQ確認收到后,消息才會從RabbitMQ服務器的數據中刪除;
- 消息的ACK確認機制默認是自動確認的,消息如果未被進行ACK的消息確認應答,這條消息被鎖定unacked;
-
確認方式
- 自動確認(默認)
- 手動確認 manual
org.springframework.amqp.core.AcknowledgeMode 消息確認枚舉
application.properties配置
#開啟手動確認消息,如果消息重新入隊,進行重試 spring.rabbitmq.listener.simple.acknowledge-mode=manual
使用了Spring Boot配置會自動生成RabbitAdmin,需要將上面的queue.order隊列消息消費的測試代碼中@RabbitListener的admin屬性去掉;
containerFactory的創建在org.springframework.boot.autoconfigure.amqp.RabbitAnnotationDrivenConfiguration#simpleRabbitListenerContainerFactory
RabbitListenerAnnotationBeanPostProcessor實現了BeanPostProcessor接口,BeanPostProcessor為bean的后置處理器,在bean初始化之前調用進行攔截,在bean初始化前后進行一些處理工作 ,說明此時的bean已經進行了實例化;
@RabbitListener上屬性的Bean則在postProcessAfterInitialization方法里創建處理;
- 死信隊列
死信轉移過程:
死信隊列配置類如下:
@Configuration public class DLXQueueConfig { @Bean public Queue productDLXQueue() { Queue queue = new Queue("queue.product.dlx"); queue.addArgument("x-message-ttl", 10000); queue.addArgument("x-dead-letter-exchange", "exchange.product.dlx"); queue.addArgument("x-dead-letter-routing-key", "key.product.dlx"); return queue; } @Bean public Exchange productExchange() { TopicExchange exchange = new TopicExchange("exchange.product"); return exchange; } @Bean public Binding productDlxQueueBinding() { Binding binding = new Binding("queue.product.dlx", Binding.DestinationType.QUEUE, "exchange.product", "key.product", null); return binding; } @Bean public Queue productQueue() { Queue queue = new Queue("queue.product"); return queue; } @Bean public Exchange productDLXExchange() { TopicExchange exchange = new TopicExchange("exchange.product.dlx"); return exchange; } @Bean public Binding productQueueBinding() { Binding binding = new Binding("queue.product", Binding.DestinationType.QUEUE, "exchange.product.dlx", "key.product.dlx", null); return binding; } }
程序啟動后創建對應的Queue,Exchange,Binding;
消息處理類
@Slf4j @Component public class DLXMessageHandler { @RabbitListener(queues = {"queue.product"}) public void handleTTLMessage(Message message, @Payload String body, Channel channel) throws IOException { long msgTag = message.getMessageProperties().getDeliveryTag(); log.info("body:{}, message:{}, msgTag:{}", body, message, msgTag); // 成功確認,使用此回執方法后,消息會被 rabbitmq broker 刪除 channel.basicAck(msgTag, false); } }
當往exchange.product交換機投遞消息,如果該消息10秒內都不消費,10秒后該隊列會變成死信隊列,將消息投遞到另一個交換機,交換機再將消息通過路由鍵路由到對應的隊列;
執行如下:
body:{"orderId":"c7f57429-41b1-483e-bf4d-edf24783e043","createDate":1624974305090,"totalAmount":null,"payAmount":null,"payType":null}, message:(Body:'[B@110ea79f(byte[128])' MessageProperties [headers={spring_listener_return_correlation=ab1b027e-aad0-4a1d-8551-6c27eac0772d, spring_returned_message_correlation=c7f57429-41b1-483e-bf4d-edf24783e043, x-first-death-exchange=exchange.product, x-death=[{reason=expired, count=1, exchange=exchange.product, time=Tue Jun 29 21:45:13 CST 2021, routing-keys=[key.product], queue=queue.product.dlx}], x-first-death-reason=expired, x-first-death-queue=queue.product.dlx}, contentType=application/octet-stream, contentLength=0, receivedDeliveryMode=PERSISTENT, priority=0, redelivered=false, receivedExchange=exchange.product.dlx, receivedRoutingKey=key.product.dlx, deliveryTag=2, consumerTag=amq.ctag-wGj9Z_aaSndUaUTKHIFC-g, consumerQueue=queue.product]), msgTag:2
當消息發送的是一個實體,不是字符串,如下:
OrderDTO orderDTO = new OrderDTO(); String uuid = UUID.randomUUID().toString(); orderDTO.setOrderId(uuid); orderDTO.setCreateDate(new Date()); CorrelationData correlationData = new CorrelationData(); correlationData.setId(uuid); rabbitTemplate.convertAndSend("exchange.product", "key.product", orderDTO, correlationData);
消息處理修改如下:
@Slf4j @Component @RabbitListener(queues = {"queue.product"}) public class DLXMessageHandler { @RabbitHandler public void handleTTLMessage(Message message, OrderDTO orderDTO, Channel channel) throws IOException { long msgTag = message.getMessageProperties().getDeliveryTag(); log.info("body:{}, message:{}, msgTag:{}", orderDTO, message, msgTag); // 成功確認,使用此回執方法后,消息會被 rabbitmq broker 刪除 channel.basicAck(msgTag, false); } }
執行如下:
body:OrderDTO(orderId=d36438b9-9cf7-48a8-a835-064b4a90201f, createDate=Tue Jun 29 22:27:19 CST 2021, totalAmount=null, payAmount=null, payType=null), message:(Body:'[B@7cae8af(byte[271])' MessageProperties [headers={spring_listener_return_correlation=77d4d8fc-7d6e-4ab9-a7bb-3d3c6ac30f02, spring_returned_message_correlation=d36438b9-9cf7-48a8-a835-064b4a90201f, x-first-death-exchange=exchange.product, x-death=[{reason=expired, count=1, exchange=exchange.product, time=Tue Jun 29 22:27:27 CST 2021, routing-keys=[key.product], queue=queue.product.dlx}], x-first-death-reason=expired, x-first-death-queue=queue.product.dlx}, contentType=application/x-java-serialized-object, contentLength=0, receivedDeliveryMode=PERSISTENT, priority=0, redelivered=false, receivedExchange=exchange.product.dlx, receivedRoutingKey=key.product.dlx, deliveryTag=3, consumerTag=amq.ctag-yukRV_EsHHtH6-pVxx6yZQ, consumerQueue=queue.product]), msgTag:3