面试官:小伙子,你给我简单说一下RocketMQ 整合 Spring Boot吧

前言

在使用SpringBoot的starter集成包时,要特别注意版本。因为SpringBoot集成RocketMQ的starter依赖是由Spring社区提供的,目前正在快速迭代的过程当中,不同版本之间的差距非常大,甚至基础的底层对象都会经常有改动。例如如果使用rocketmq-spring-boot-starter:2.0.4版本开发的代码,升级到目前最新的rocketmq-spring-boot-starter:2.1.1后,基本就用不了了

应用结构

面试官:小伙子,你给我简单说一下RocketMQ 整合 Spring Boot吧_第1张图片

TestController: 测试入口, 有基本消息测试和事务消息测试
TopicListener: 是监听"topic"这个主题的普通消息监听器
TopicTransactionListener: 是监听"topic"这个主题的事务消息监听器, 和TopicTransactionRocketMQTemplate绑定(一一对应关系)
Customer: 是测试消息体的一个entity对象
TopicTransactionRocketMQTemplate: 是扩展自RocketMQTemplate的另一个RocketMQTemplate, 专门用来处理某一个业务流程, 和TopicTransactionListener绑定(一一对应关系)

pom.xml

org.apache.rocketmq:rocketmq-spring-boot-starter:2.1.1, 引用的springboot版本是2.0.5.RELEASE



    4.0.0
    com.mrathena.middle.ware
    rocket.mq.springboot
    1.0.0
    
        
            
                org.springframework.boot
                spring-boot-dependencies
                2.4.0
                pom
                import
            
        
    
    
        
            org.projectlombok
            lombok
            1.18.12
        
        
            org.slf4j
            slf4j-api
            1.7.30
        
        
            ch.qos.logback
            logback-classic
            1.2.3
        
        
            org.apache.rocketmq
            rocketmq-spring-boot-starter
            2.1.1
            
            
                
                    org.springframework.boot
                    spring-boot-starter
                
                
                    org.springframework
                    spring-core
                
                
                    org.springframework
                    spring-webmvc
                
                
                    org.springframework
                    spring-aop
                
                
                    org.springframework
                    spring-context
                
                
                    org.springframework
                    spring-messaging
                
                
                    com.fasterxml.jackson.core
                    jackson-databind
                
            
        
        
            org.springframework.boot
            spring-boot-starter-web
        
        
            org.springframework.boot
            spring-boot-starter-test
        
        
            org.springframework
            spring-messaging
        
        
            com.fasterxml.jackson.core
            jackson-databind
        
        
            io.springfox
            springfox-swagger-ui
            2.9.2
        
        
            io.springfox
            springfox-swagger2
            2.9.2
        
    
    
        
            
                org.apache.maven.plugins
                maven-compiler-plugin
                3.8.1
                
                    1.8
                    1.8
                    UTF-8
                
            
        
    

application.yml

server:
  servlet:
    context-path:
  port: 80
rocketmq:
  name-server: 116.62.162.48:9876
  producer:
    group: producer

Customer

package com.mrathena.rocket.mq.entity;

import lombok.AllArgsConstructor;
import lombok.Getter;
import lombok.NoArgsConstructor;
import lombok.Setter;

@Getter
@Setter
@NoArgsConstructor
@AllArgsConstructor
public class Customer {
    private String username;
    private String nickname;
}

生产者 TestController

package com.mrathena.rocket.mq.controller;

import com.mrathena.rocket.mq.configuration.TopicTransactionRocketMQTemplate;
import com.mrathena.rocket.mq.entity.Customer;
import lombok.extern.slf4j.Slf4j;
import org.apache.rocketmq.client.producer.SendCallback;
import org.apache.rocketmq.client.producer.SendResult;
import org.apache.rocketmq.spring.core.RocketMQTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.messaging.Message;
import org.springframework.messaging.MessageHeaders;
import org.springframework.messaging.core.MessagePostProcessor;
import org.springframework.messaging.support.MessageBuilder;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import java.util.HashMap;
import java.util.Map;

@Slf4j
@RestController
@RequestMapping("test")
public class TestController {

    private static final String TOPIC = "topic";

    @Autowired
    private RocketMQTemplate rocketMQTemplate;
    @Autowired
    private TopicTransactionRocketMQTemplate topicTransactionRocketMQTemplate;

    @GetMapping("base")
    public Object base() {
        // destination: topic/topic:tag, topic或者是topic拼接tag的整合体
        // payload: 荷载即消息体
        // message: org.springframework.messaging.Message, 是Spring自己封装的类, 和RocketMQ的Message不是一个类, 里面没有tags/keys等内容
        rocketMQTemplate.send(TOPIC, MessageBuilder.withPayload("你好").setHeader("你是谁", "你猜").build());
        // tags null
        rocketMQTemplate.convertAndSend(TOPIC, "tag null");
        // tags empty, 证明 tag 要么有值要么null, 不存在 empty 的 tag
        rocketMQTemplate.convertAndSend(TOPIC + ":", "tag empty ?");
        // 只有 tag 没有 key
        rocketMQTemplate.convertAndSend(TOPIC + ":a", "tag a");
        rocketMQTemplate.convertAndSend(TOPIC + ":b", "tag b");
        // 有 property, 即 RocketMQ 基础 API 里面, Message(String topic, String tags, String keys, byte[] body) 里面的 key
        // rocketmq-spring-boot-starter 把 userProperty 和其他的一些属性都糅合在 headers 里面可, 具体可以参考 org.apache.rocketmq.spring.support.RocketMQUtil.addUserProperties
        // 获取某个自定义的属性的时候, 直接 headers.get("自定义属性key") 就可以了
        Map properties = new HashMap<>();
        properties.put("property", 1);
        properties.put("another-property", "你好");
        rocketMQTemplate.convertAndSend(TOPIC, "property 1", properties);
        rocketMQTemplate.convertAndSend(TOPIC + ":a", "tag a property 1", properties);
        rocketMQTemplate.convertAndSend(TOPIC + ":b", "tag b property 1", properties);
        properties.put("property", 5);
        rocketMQTemplate.convertAndSend(TOPIC, "property 5", properties);
        rocketMQTemplate.convertAndSend(TOPIC + ":a", "tag a property 5", properties);
        rocketMQTemplate.convertAndSend(TOPIC + ":c", "tag c property 5", properties);

        // 消息后置处理器, 可以在发送前对消息体和headers再做一波操作
        rocketMQTemplate.convertAndSend(TOPIC, "消息后置处理器", new MessagePostProcessor() {
            /**
             * org.springframework.messaging.Message
             */
            @Override
            public Message postProcessMessage(Message message) {
                Object payload = message.getPayload();
                MessageHeaders messageHeaders = message.getHeaders();
                return message;
            }
        });

        // convertAndSend 底层其实也是 syncSend
        // syncSend
        log.info("{}", rocketMQTemplate.syncSend(TOPIC, "sync send"));
        // asyncSend
        rocketMQTemplate.asyncSend(TOPIC, "async send", new SendCallback() {
            @Override
            public void onSuccess(SendResult sendResult) {
                log.info("onSuccess");
            }

            @Override
            public void onException(Throwable e) {
                log.info("onException");
            }
        });
        // sendOneWay
        rocketMQTemplate.sendOneWay(TOPIC, "send one way");

        // 这个我还是不太清楚是干嘛的? 跑的时候会报错!!!
//        Object receive = rocketMQTemplate.sendAndReceive(TOPIC, "你好", String.class);
//        log.info("{}", receive);

        return "success";
    }

    @GetMapping("transaction")
    public Object transaction() {
        Message message = MessageBuilder.withPayload(new Customer("mrathena", "你是谁")).build();
        // 这里使用的是通过 @ExtRocketMQTemplateConfiguration(group = "anotherProducer") 扩展出来的另一个 RocketMQTemplate
        log.info("{}", topicTransactionRocketMQTemplate.sendMessageInTransaction(TOPIC, message, null));
        log.info("{}", topicTransactionRocketMQTemplate.sendMessageInTransaction(TOPIC + ":tag-a", message, null));
        return "success";
    }

}

配置 TopicTransactionRocketMQTemplate

package com.mrathena.rocket.mq.configuration;

import org.apache.rocketmq.spring.annotation.ExtRocketMQTemplateConfiguration;
import org.apache.rocketmq.spring.core.RocketMQTemplate;

/**
 * 一个事务流程和一个RocketMQTemplate需要一一对应
 * 可以通过 @ExtRocketMQTemplateConfiguration(注意该注解有@Component注解) 来扩展多个 RocketMQTemplate
 * 注意: 不同事务流程的RocketMQTemplate的producerGroup不能相同
 * 因为MQBroker会反向调用同一个producerGroup下的某个checkLocalTransactionState方法, 不同流程使用相同的producerGroup的话, 方法可能会调用错
 */
@ExtRocketMQTemplateConfiguration(group = "anotherProducer")
public class TopicTransactionRocketMQTemplate extends RocketMQTemplate {}

消费者 TopicListener

package com.mrathena.rocket.mq.listener;

import lombok.extern.slf4j.Slf4j;
import org.apache.rocketmq.spring.annotation.ConsumeMode;
import org.apache.rocketmq.spring.annotation.MessageModel;
import org.apache.rocketmq.spring.annotation.RocketMQMessageListener;
import org.apache.rocketmq.spring.core.RocketMQListener;
import org.springframework.stereotype.Component;

/**
 * 最简单的消费者例子
 * topic: 主题
 * consumerGroup: 消费者组
 * selectorType: 过滤方式, TAG:标签过滤,仅支持标签, SQL92:SQL过滤,支持标签和属性
 * selectorExpression: 过滤表达式, 根据selectorType定, TAG时, 写标签如 "a || b", SQL92时, 写SQL表达式
 * consumeMode: CONCURRENTLY:并发消费, ORDERLY:顺序消费
 * messageModel: CLUSTERING:集群竞争消费, BROADCASTING:广播消费
 */
@Slf4j
@Component
@RocketMQMessageListener(topic = "topic",
        // 只过滤tag, 不管headers中的key和value
//        selectorType = SelectorType.TAG,
        // 必须指定selectorExpression, 可以过滤tag和headers中的key和value
//        selectorType = SelectorType.SQL92,
        // 不限tag
//        selectorExpression = "*",
        // 不限tag, 和 * 一致
//        selectorExpression = "",
        // 只要tag为a的消息
//        selectorExpression = "a",
        // 要tag为a或b的消息
//        selectorExpression = "a || b",
        // SelectorType.SQL92时, 可以跳过tag, 直接用headers里面的key和value来判断
//        selectorExpression = "property = 1",
        // tag不为null
//        selectorExpression = "TAGS is not null",
        // tag为empty, 证明tag不会是empty, 要么有值要么null
//        selectorExpression = "TAGS = ''",
        // SelectorType.SQL92时, 即过滤tag, 又过滤headers里面的key和value
//        selectorExpression = "(TAGS is not null and TAGS = 'a') and (property is not null and property between 4 and 6)",
        // 并发消费
        consumeMode = ConsumeMode.CONCURRENTLY,
        // 顺序消费
//        consumeMode = ConsumeMode.ORDERLY,
        // 集群消费
        messageModel = MessageModel.CLUSTERING,
        // 广播消费
//        messageModel = MessageModel.BROADCASTING,
        consumerGroup = "consumer"
)
public class TopicListener implements RocketMQListener {
    public void onMessage(String s) {
        log.info("{}", s);
    }
}

消费者 TopicTransactionListener

package com.mrathena.rocket.mq.listener;

import lombok.extern.slf4j.Slf4j;
import org.apache.rocketmq.spring.annotation.RocketMQTransactionListener;
import org.apache.rocketmq.spring.core.RocketMQLocalTransactionListener;
import org.apache.rocketmq.spring.core.RocketMQLocalTransactionState;
import org.apache.rocketmq.spring.support.RocketMQHeaders;
import org.springframework.messaging.Message;
import org.springframework.messaging.MessageHeaders;
import org.springframework.stereotype.Component;

@Slf4j
@Component
@RocketMQTransactionListener(rocketMQTemplateBeanName = "topicTransactionRocketMQTemplate")
public class TopicTransactionListener implements RocketMQLocalTransactionListener {

    @Override
    public RocketMQLocalTransactionState executeLocalTransaction(Message message, Object o) {
        // message: org.springframework.messaging.Message, 是Spring自己封装的类, 和RocketMQ的Message不是一个类, 里面没有tags/keys等内容
        // 一般来说, 并不会在这里处理tags/keys等内容, 而是根据消息体中的某些字段做不同的操作, 第二个参数也可以用来传递一些数据到这里
        log.info("executeLocalTransaction message:{}, object:{}", message, o);
        log.info("payload: {}", new String((byte[]) message.getPayload()));
        MessageHeaders headers = message.getHeaders();
        log.info("tags: {}", headers.get(RocketMQHeaders.PREFIX + RocketMQHeaders.TAGS));
        log.info("rocketmq_TOPIC: {}", headers.get("rocketmq_TOPIC"));
        log.info("rocketmq_QUEUE_ID: {}", headers.get("rocketmq_QUEUE_ID"));
        log.info("rocketmq_MESSAGE_ID: {}", headers.get("rocketmq_MESSAGE_ID"));
        log.info("rocketmq_TRANSACTION_ID: {}", headers.get("rocketmq_TRANSACTION_ID"));
        log.info("TRANSACTION_CHECK_TIMES: {}", headers.get("TRANSACTION_CHECK_TIMES"));
        log.info("id: {}", headers.get("id"));
        return RocketMQLocalTransactionState.UNKNOWN;
    }

    @Override
    public RocketMQLocalTransactionState checkLocalTransaction(Message message) {
        log.info("checkLocalTransaction message:{}", message);
        // 在调用了checkLocalTransaction后, 另一个常规消息监听器才能收到消息
        return RocketMQLocalTransactionState.COMMIT;
    }
}

最后

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