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SpringBoot集成RabbitMQ(五)

2019-04-06  本文已影响59人  3d0829501918

一、RabbitMQ

   RabbitMQ 即一个消息队列,主要是用来实现应用程序的异步和解耦,同时也能起到消息缓冲,消息分发的作用。
   消息中间件最主要的作用是解耦,中间件最标准的用法是生产者生产消息传送到队列,消费者从队列中拿取消息并处理,生产者不用关心是谁来消费,消费者不用关心谁在生产消息,从而达到解耦的目的。在分布式的系统中,消息队列也会被用在很多其它的方面,比如:分布式事务的支持,RPC的调用等等。

  对于消息队列,我们一般知道有三个概念:发消息者、队列、收消息者,RabbitMQ 在这个基本概念之上,多做了一层抽象,在发消息者和队列之间,加入了交换器(Exchange)这样发消息者和队列就没有直接联系,转而变成发消息者把消息给交换器,交换器根据调度策略再把消息再给队列。


   左侧P代表生产者,也就是往RabbitMQ发消息的程序。
   中间即是RabbitMQ,其中绿色的X代表交换机,红色的通道代表队列。
   右侧C代表消费者,也就是往RabbitMQ拿消息的程序。

  交换机的功能主要是接收消息并且转发到绑定的队列。
  交换机类型: Direct类型Topic类型Headers类型Fanout类型
  Direct是RabbitMQ默认的交换机模式,也是最简单的模式.即创建消息队列的时候,指定一个BindingKey.当发送者发送消息的时候,指定对应的Key.当Key和消息队列的BindingKey一致的时候,消息将会被发送到该消息队列中。
  Topic 转发信息主要是依据通配符,队列和交换机的绑定主要是依据一种模式(通配符+字符串),而当发送消息的时候,只有指定的Key和该模式相匹配的时候,消息才会被发送到该消息队列中。
  Headers是根据一个规则进行匹配,在消息队列和交换机绑定的时候会指定一组键值对规则,而发送消息的时候也会指定一组键值对规则,当两组键值对规则相匹配的时候,消息会被发送到匹配的消息队列中。
  Fanout 是路由广播的形式,将会把消息发给绑定它的全部队列,即便设置了key,也会被忽略。


  RabbitMQ 即一个消息队列,主要是用来实现应用程序的异步和解耦,同时也能起到消息缓冲,消息分发的作用。

二、Direct类型

  <dependency>
     <groupId>org.springframework.boot</groupId>
     <artifactId>spring-boot-starter-amqp</artifactId>
  </dependency>
  #配置rabbitmq的安装地址、端口以及账户信息
  #注意port 15672是管理端的端口
  spring.application.name=spirng-boot-rabbitmq-sender
  spring.rabbitmq.host=127.0.0.1
  spring.rabbitmq.port=5672
  spring.rabbitmq.username=guest
  spring.rabbitmq.password=guest
 @Configuration
 public class RabbitConfig {

      @Bean
      public Queue helloQueue() {
             return new Queue("hello");
      }
 }
@Component
public class HelloSender {

     @Autowired
     private AmqpTemplate rabbitTemplate;

     public void send() {
             String context = "hello " + new Date();
             System.out.println("Sender : " + context);
             this.rabbitTemplate.convertAndSend("hello", context);
     }
}
@Component
@RabbitListener(queues = "hello")
public class HelloReceiver {

     @RabbitHandler
     public void process(String hello) {
            System.out.println("Receiver  : " + hello);
     }
}
@RunWith(SpringRunner.class)
@SpringBootTest
public class Test {

     @Autowired
     private HelloSender helloSender;

   // 发送单条消息
    @org.junit.Test
    public void contextLoads() {
           helloSender.send();
    }
 }
Sender : hello Sun Jan 06 10:58:18 CST 2019
2019-01-06 10:58:18.530  INFO 24784 --- [       Thread-2] 
o.s.a.r.l.SimpleMessageListenerContainer : Waiting for workers to finish.
Receiver  : hello Sun Jan 06 10:58:18 CST 2019

发送者和接收者的queue name必须一致,不然接收不到消息。Direct模式相当于一对一模式,一个消息被发送者发送后,会被转发到一个绑定的消息队列中,然后被一个接收者接收。


三、Direct发送对象

public void send(User user) {
    System.out.println("Sender object: " + user.toString());
    this.rabbitTemplate.convertAndSend("object", user);
}
@RabbitHandler
public void process(User user) {
    System.out.println("Receiver object : " + user);
    System.out.println("username:"+user.getUsername());
    System.out.println("password:"+user.getPassword());
}
// 发送对象
@org.junit.Test
public void sendObj() {
    User user = new User();
    user.setId(1);
    user.setUsername("admin");
    user.setPassword("1234");
    objectSender.send(user);
}
 Sender object: com.example.bean.User@fa5f81c
 2019-01-06 11:13:40.175  INFO 26456 --- [       Thread-2] 
 o.s.a.r.l.SimpleMessageListenerContainer : Waiting for workers to finish.
 Receiver object : com.example.bean.User@7b0f425
 username:admin
 password:1234

四、Topic类型

  Topic 是 RabbitMQ中最灵活的一种方式,可以根据routing_key自由的绑定不同的队列。


@Configuration
public class TopicRabbitConfig {

       final static String message = "topic.message";
       final static String messages = "topic.messages";
      // 创建队列
      @Bean
      public Queue queueMessage() {
            return new Queue(TopicRabbitConfig.message);
      }
      // 创建队列
      @Bean
      public Queue queueMessages() {
             return new Queue(TopicRabbitConfig.messages);
      }
      // 将对列绑定到Topic交换器
      @Bean
      TopicExchange exchange() {
            return new TopicExchange("topicExchange");
      }
      // 将对列绑定到Topic交换器
      @Bean
      Binding bindingExchangeMessage(Queue queueMessage, TopicExchange exchange) {
            return BindingBuilder.bind(queueMessage).to(exchange).with("topic.message");
      }
      // 将对列绑定到Topic交换器 采用#的方式
      @Bean
      Binding bindingExchangeMessages(Queue queueMessages, TopicExchange exchange) {
            return BindingBuilder.bind(queueMessages).to(exchange).with("topic.#");
      }
}
public void send1() {
    String context = "hi, i am message 1";
    System.out.println("Sender : " + context);
    this.rabbitTemplate.convertAndSend("topicExchange", "topic.message", context);
}

public void send2() {
    String context = "hi, i am messages 2";
    System.out.println("Sender : " + context);
    this.rabbitTemplate.convertAndSend("topicExchange", "topic.messages", context);
}
@Component
@RabbitListener(queues = "topic.message")
public class TopicReceiver {
       @RabbitHandler
       public void process(String message) {
           System.out.println("Topic Receiver1  : " + message);
       }
}

发送send1会匹配到topic.#和topic.message 两个Receiver都可以收到消息,发送send2只有topic.#可以匹配所有只有Receiver2监听到消息

 @RunWith(SpringRunner.class)
 @SpringBootTest
 public class Test {

     @Autowired
     private TopicSender topicSender;

    @org.junit.Test
    public void send1() {
       topicSender.send1();
    }
   @org.junit.Test
    public void send2() {
       topicSender.send2();
    }
}

发送send1会匹配到topic.#和topic.message 两个Receiver都可以收到消息,发送send2只有topic.#可以匹配所有只有Receiver2监听到消息。


五、Headers类型

配置一个routingKey为credit.bank的消息队列并绑定在creditBankExchange交换机上
配置一个routingKey为credit.finance的消息队列并绑定在creditFinanceExchange交换机上

@Configuration
public class HeadersConfig {

     @Bean
     public Queue creditBankQueue() {
            return new Queue("credit.bank");
     }

     @Bean
     public Queue creditFinanceQueue() {
            return new Queue("credit.finance");
     }

     @Bean
     public HeadersExchange creditBankExchange() {
            return new HeadersExchange("creditBankExchange");
     }

     @Bean
     public HeadersExchange creditFinanceExchange() {
            return new HeadersExchange("creditFinanceExchange");
     } 

     @Bean
     public Binding bindingCreditAExchange(Queue creditBankQueue, HeadersExchange creditBankExchange) {
          Map<String,Object> headerValues = new HashMap<>();
          headerValues.put("type", "cash");
          headerValues.put("aging", "fast");
          return BindingBuilder.bind(creditBankQueue).to(creditBankExchange).whereAll(headerValues).match();
    }

     @Bean
     public Binding bindingCreditBExchange(Queue creditFinanceQueue, HeadersExchange creditFinanceExchange) {
          Map<String,Object> headerValues = new HashMap<>();
          headerValues.put("type", "cash");
          headerValues.put("aging", "fast");
          return BindingBuilder.bind(creditFinanceQueue).to(creditFinanceExchange).whereAny(headerValues).match();
     }
}
@Component
public class ApiCreditSender {

            @Autowired
            private AmqpTemplate rabbitTemplate;

            public void creditBank(Map<String, Object> head, String msg){
                   System.out.println("credit.bank send message: "+msg);
                   rabbitTemplate.convertAndSend("creditBankExchange", "credit.bank", getMessage(head, msg));
            }

            public void creditFinance(Map<String, Object> head, String msg){
                   System.out.println("credit.finance send message: "+msg);
                   rabbitTemplate.convertAndSend("creditFinanceExchange", "credit.finance", getMessage(head, msg));
            }

            private Message getMessage(Map<String, Object> head, Object msg){
                    MessageProperties messageProperties = new MessageProperties();
                    for (Map.Entry<String, Object> entry : head.entrySet()) {
                             messageProperties.setHeader(entry.getKey(), entry.getValue());
                    }
                    MessageConverter messageConverter = new SimpleMessageConverter();
                    return messageConverter.toMessage(msg, messageProperties);
             }
}
@Component
public class ApiCreditReceive {

    @RabbitHandler
    @RabbitListener(queues = "credit.bank")
    public void creditBank(String msg) {
           System.out.println("credit.bank receive message: "+msg);
    }

     @RabbitHandler
     @RabbitListener(queues = "credit.finance")
     public void creditFinance(String msg) {
           System.out.println("credit.bank receive message: "+msg);
     }
 }
@RunWith(SpringRunner.class)
@SpringBootTest
public class Test {

        @Autowired
        private ApiCreditSender sender;

         @org.junit.Test
         public void test_creditBank_type() {
              Map<String,Object> head = new HashMap<>();
              head.put("type", "cash");
              sender.creditBank(head, "银行授信(部分匹配)");
         }

        @org.junit.Test
        public void test_creditBank_all() {
             Map<String,Object> head = new HashMap<>();
             head.put("type", "cash");
             head.put("aging", "fast");
             sender.creditBank(head, "银行授信(全部匹配)");
        }

        @org.junit.Test
        public void test_creditFinance_type() {
             Map<String,Object> head = new HashMap<>();
             head.put("type", "cash");
             sender.creditFinance(head, "金融公司授信(部分匹配)");
        }

        @org.junit.Test
        public void test_creditFinance_all() {
               Map<String,Object> head = new HashMap<>();
               head.put("type", "cash");
               head.put("aging", "fast");
               sender.creditFinance(head, "金融公司授信(全部匹配)");
        }
}
 // 发送者日志
 credit.bank send message: 银行授信(部分匹配)
 credit.finance send message: 金融公司授信(全部匹配)
 credit.bank send message: 银行授信(全部匹配)
 credit.finance send message: 金融公司授信(部分匹配)
 // 接收者日志
 credit.bank receive message: 银行授信(全部匹配)
 credit.bank receive message: 金融公司授信(全部匹配)
 credit.bank receive message: 金融公司授信(部分匹配)

分析日志:
  通过发送者日志中可以看出4个测试方法均已成功发送消息。
  通过接收者日志可以看出credit.bank监听的队列有一条消息没有接收到。

  ApiCreditSenderTests.test_creditBank_type()为什么发送的消息,没有被处理?
  答:因为在HeadersConfig配置类中,creditBankExchange交换机的匹配规则是完全匹配,即header attribute参数必须完成一致。


六、Fanout类型


  FanoutExchange交换机是转发消息到所有绑定队列(和routingKey没有关系),即我们熟悉的广播模式或者订阅模式,给Fanout交换机发送消息,绑定了这个交换机的所有队列都收到这个消息。
@Configuration
 public class FanoutRabbitConfig {
      // 创建队列
     @Bean
     public Queue AMessage() {
          return new Queue("fanout.A");
     }
     // 创建队列
     @Bean
     public Queue BMessage() {
          return new Queue("fanout.B");
     }
     // 创建队列
     @Bean
     public Queue CMessage() {
          return new Queue("fanout.C");
     }
     // 创建Fanout交换器
     @Bean
     FanoutExchange fanoutExchange() {
          return new FanoutExchange("fanoutExchange");
     }
     // 将对列绑定到Fanout交换器
     @Bean
     Binding bindingExchangeA(Queue AMessage, FanoutExchange fanoutExchange) {
          return BindingBuilder.bind(AMessage).to(fanoutExchange);
     }
     // 将对列绑定到Fanout交换器
     @Bean
     Binding bindingExchangeB(Queue BMessage, FanoutExchange fanoutExchange) {
          return BindingBuilder.bind(BMessage).to(fanoutExchange);
     }
     // 将对列绑定到Fanout交换器
     @Bean
     Binding bindingExchangeC(Queue CMessage, FanoutExchange fanoutExchange) {
          return BindingBuilder.bind(CMessage).to(fanoutExchange);
     }
}
@Component
public class FanoutSender {

       @Autowired
       private AmqpTemplate rabbitTemplate;

       public void send() {
             String context = "hi, fanout msg ";
             System.out.println("Sender : " + context);
             this.rabbitTemplate.convertAndSend("fanoutExchange","", context);
       }
}

  这里使用了A、B、C三个队列绑定到Fanout交换机上面,发送端的routing_key写任何字符都会被忽略。

@RabbitHandler
public void process(String message) {
    System.out.println("fanout Receiver A  : " + message);
}
@RunWith(SpringRunner.class)
@SpringBootTest
public class Test {

       @Autowired
       private FanoutSender fanoutSender;

       @org.junit.Test
       public void sendFanout () {
           fanoutSender.send();
       }
}
fanout Receiver B: hi, fanout msg 
fanout Receiver A  : hi, fanout msg 
fanout Receiver C: hi, fanout msg 

本文中的代码在这里:
    https://github.com/xiaonongOne/springboot-rabbitmq


注意啦! 往期SpringBoot在这里


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