不要以为这只是spring boot与RocketMQ的简单整合,本篇文章还为各位看官呈现以下知识点的最佳实践:
- 自定义一个spring boot 的starter
- 使用spring的事件传播机制实现bean与bean之间基于事件驱动的通信
- 自定义注解、组合注解
先来撩点故事背景^_^
编写spring-boot-starter-rocketmq
创建一个Maven项目名字就叫spring-boot-starter-rocketmq,其pom.xml文件内容如下:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<groupId>com.bqjr</groupId>
<version>0.0.1-SNAPSHOT</version>
<name>spring-boot-starter-rocketmq</name>
<description>Starter for using RocketMQ</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.3.RELEASE</version>
<relativePath/>
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
<rocketmq.version>4.0.0-incubating</rocketmq.version>
</properties>
<modelVersion>4.0.0</modelVersion>
<artifactId>spring-boot-starter-rocketmq</artifactId>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<!-- RocketMq客户端相关依赖 -->
<dependency>
<groupId>org.apache.rocketmq</groupId>
<artifactId>rocketmq-client</artifactId>
<version>${rocketmq.version}</version>
</dependency>
<dependency>
<groupId>org.apache.rocketmq</groupId>
<artifactId>rocketmq-common</artifactId>
<version>${rocketmq.version}</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.16.10</version><!--$NO-MVN-MAN-VER$-->
</dependency>
</dependencies>
</project>
编写配置类RocketmqProperties,这个类的属性对应application.properties文件中的配置项,目前只提供核心的一些配置支持,其他性能优化方面的配置参数可自行扩展
/**
* @author jiangjb
*/
@Data
@ConfigurationProperties(PREFIX)
public class RocketmqProperties {
public static final String PREFIX = "spring.extend.rocketmq";
private String namesrvAddr;
private String instanceName;
private String clientIP;
private ProducerConfig producer;
private ConsumerConfig consumer;
}
编写配置解析类RocketmqAutoConfiguration,这个类主要初始化了三个Bean:defaultProducer用来发送普通消息、transactionProducer用来发送事务消息以及pushConsumer用来接收订阅的所有topic下的消息,并派发给不同的tag的消费者。/**
* @author jiangjb
*/
@Configuration
@EnableConfigurationProperties(RocketmqProperties.class)
@ConditionalOnProperty(prefix = PREFIX, value = "namesrvAddr")
public class RocketmqAutoConfiguration {
@Autowired
private RocketmqProperties properties;
@Value("${spring.application.name}")
private String producerGroupName;
@Value("${spring.application.name}")
private String consumerGroupName;
@Autowired
private ApplicationEventPublisher publisher;
/**
* 初始化向rocketmq发送普通消息的生产者
*/
@Bean
@ConditionalOnProperty(prefix = PREFIX, value = "producer.instanceName")
public DefaultMQProducer defaultProducer() throws MQClientException{
/**
* 一个应用创建一个Producer,由应用来维护此对象,可以设置为全局对象或者单例<br>
* 注意:ProducerGroupName需要由应用来保证唯一<br>
* ProducerGroup这个概念发送普通的消息时,作用不大,但是发送分布式事务消息时,比较关键,
* 因为服务器会回查这个Group下的任意一个Producer
*/
DefaultMQProducer producer = new DefaultMQProducer(producerGroupName);
producer.setNamesrvAddr(properties.getNamesrvAddr());
producer.setInstanceName(properties.getProducer().getInstanceName());
producer.setVipChannelEnabled(false);
/**
* Producer对象在使用之前必须要调用start初始化,初始化一次即可<br>
* 注意:切记不可以在每次发送消息时,都调用start方法
*/
producer.start();
System.out.println("RocketMq defaultProducer Started.");
return producer;
}
/**
* 初始化向rocketmq发送事务消息的生产者
*/
@Bean
@ConditionalOnProperty(prefix = PREFIX, value = "producer.tranInstanceName")
public TransactionMQProducer transactionProducer() throws MQClientException{
/**
* 一个应用创建一个Producer,由应用来维护此对象,可以设置为全局对象或者单例<br>
* 注意:ProducerGroupName需要由应用来保证唯一<br>
* ProducerGroup这个概念发送普通的消息时,作用不大,但是发送分布式事务消息时,比较关键,
* 因为服务器会回查这个Group下的任意一个Producer
*/
TransactionMQProducer producer = new TransactionMQProducer("TransactionProducerGroupName");
producer.setNamesrvAddr(properties.getNamesrvAddr());
producer.setInstanceName(properties.getProducer().getTranInstanceName());
// 事务回查最小并发数
producer.setCheckThreadPoolMinSize(2);
// 事务回查最大并发数
producer.setCheckThreadPoolMaxSize(2);
// 队列数
producer.setCheckRequestHoldMax(2000);
//TODO 由于社区版本的服务器阉割调了消息回查的功能,所以这个地方没有意义
//TransactionCheckListener transactionCheckListener = new TransactionCheckListenerImpl();
//producer.setTransactionCheckListener(transactionCheckListener);
/**
* Producer对象在使用之前必须要调用start初始化,初始化一次即可<br>
* 注意:切记不可以在每次发送消息时,都调用start方法
*/
producer.start();
System.out.println("RocketMq TransactionMQProducer Started.");
return producer;
}
/**
* 初始化rocketmq消息监听方式的消费者
*/
@Bean
@ConditionalOnProperty(prefix = PREFIX, value = "consumer.instanceName")
public DefaultMQPushConsumer pushConsumer() throws MQClientException{
/**
* 一个应用创建一个Consumer,由应用来维护此对象,可以设置为全局对象或者单例<br>
* 注意:ConsumerGroupName需要由应用来保证唯一
*/
DefaultMQPushConsumer consumer = new DefaultMQPushConsumer(consumerGroupName);
consumer.setConsumeFromWhere(ConsumeFromWhere.CONSUME_FROM_FIRST_OFFSET);
consumer.setNamesrvAddr(properties.getNamesrvAddr());
consumer.setInstanceName(properties.getConsumer().getInstanceName());
consumer.setConsumeMessageBatchMaxSize(1);//设置批量消费,以提升消费吞吐量,默认是1
/**
* 订阅指定topic下tags
*/
List<String> subscribeList = properties.getConsumer().getSubscribe();
for (String sunscribe : subscribeList) {
consumer.subscribe(sunscribe.split(":")[0], sunscribe.split(":")[1]);
}
consumer.registerMessageListener((List<MessageExt> msgs, ConsumeConcurrentlyContext context) -> {
MessageExt msg = msgs.get(0);
try {
//默认msgs里只有一条消息,可以通过设置consumeMessageBatchMaxSize参数来批量接收消息
System.out.println(Thread.currentThread().getName() + " Receive New Messages: " + msgs.size());
//发布消息到达的事件,以便分发到每个tag的监听方法
this.publisher.publishEvent(new RocketmqEvent(msg,consumer));
System.out.println("消息到达事件已经发布成功!");
} catch (Exception e) {
e.printStackTrace();
if(msg.getReconsumeTimes()<=3){//重复消费3次
//TODO 进行日志记录
return ConsumeConcurrentlyStatus.RECONSUME_LATER;
} else {
//TODO 消息消费失败,进行日志记录
}
}
//如果没有return success,consumer会重复消费此信息,直到success。
return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
});
new Thread(new Runnable() {
@Override
public void run() {
try {
Thread.sleep(5000);//延迟5秒再启动,主要是等待spring事件监听相关程序初始化完成,否则,回出现对RocketMQ的消息进行消费后立即发布消息到达的事件,然而此事件的监听程序还未初始化,从而造成消息的丢失
/**
* Consumer对象在使用之前必须要调用start初始化,初始化一次即可<br>
*/
try {
consumer.start();
} catch (Exception e) {
System.out.println("RocketMq pushConsumer Start failure!!!.");
e.printStackTrace();
}
System.out.println("RocketMq pushConsumer Started.");
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}).start();
return consumer;
}
}
编写基于spring事件传播机制的事件类RocketmqEvent,用来定义上面的consumer接收到消息后的发布的事件。
/**
*
* @author jiangjb
*
*/
@Data
@EqualsAndHashCode(callSuper=false)
public class RocketmqEvent extends ApplicationEvent{
private static final long serialVersionUID = -4468405250074063206L;
private DefaultMQPushConsumer consumer;
private MessageExt messageExt;
private String topic;
private String tag;
private byte[] body;
public RocketmqEvent(MessageExt msg,DefaultMQPushConsumer consumer) throws Exception {
super(msg);
this.topic = msg.getTopic();
this.tag = msg.getTags();
this.body = msg.getBody();
this.consumer = consumer;
this.messageExt = msg;
}
public String getMsg() {
try {
return new String(this.body,"utf-8");
} catch (UnsupportedEncodingException e) {
return null;
}
}
public String getMsg(String code) {
try {
return new String(this.body,code);
} catch (UnsupportedEncodingException e) {
return null;
}
}
}
然后运行maven的编译、打包编写测试项目rocketmq-starter-test
<dependency>
<groupId>com.bqjr</groupId>
<artifactId>spring-boot-starter-rocketmq</artifactId>
<version>0.0.1-SNAPSHOT</version>
</dependency>
发送消息测试类producerDemo/**
*
* @author jiangjb
*
*/
@RestController
public class producerDemo {
@Autowired
private DefaultMQProducer defaultProducer;
@Autowired
private TransactionMQProducer transactionProducer;
@Value("${spring.extend.rocketmq.producer.topic}")
private String producerTopic;
@RequestMapping(value = "/sendMsg", method = RequestMethod.GET)
public void sendMsg() {
Message msg = new Message(producerTopic,// topic
"TagA",// tag
"OrderID001",// key
("Hello jyqlove333").getBytes());// body
try {
defaultProducer.send(msg,new SendCallback(){
@Override
public void onSuccess(SendResult sendResult) {
System.out.println(sendResult);
//TODO 发送成功处理
}
@Override
public void onException(Throwable e) {
System.out.println(e);
//TODO 发送失败处理
}
});
} catch (Exception e) {
e.printStackTrace();
}
}
@RequestMapping(value = "/sendTransactionMsg", method = RequestMethod.GET)
public String sendTransactionMsg() {
SendResult sendResult = null;
try {
//构造消息
Message msg = new Message(producerTopic,// topic
"TagA",// tag
"OrderID001",// key
("Hello jyqlove333").getBytes());// body
//发送事务消息,LocalTransactionExecute的executeLocalTransactionBranch方法中执行本地逻辑
sendResult = transactionProducer.sendMessageInTransaction(msg, (Message msg1,Object arg) -> {
int value = 1;
//TODO 执行本地事务,改变value的值
//===================================================
System.out.println("执行本地事务。。。完成");
if(arg instanceof Integer){
value = (Integer)arg;
}
//===================================================
if (value == 0) {
throw new RuntimeException("Could not find db");
} else if ((value % 5) == 0) {
return LocalTransactionState.ROLLBACK_MESSAGE;
} else if ((value % 4) == 0) {
return LocalTransactionState.COMMIT_MESSAGE;
}
return LocalTransactionState.ROLLBACK_MESSAGE;
}, 4);
System.out.println(sendResult);
} catch (Exception e) {
e.printStackTrace();
}
return sendResult.toString();
}
}
消费消息测试类consumerDemo
/**
*
* @author jiangjb
*
*/
@Component
public class consumerDemo {
@EventListener(condition = "#event.topic=='TopicTest1' && #event.tag=='TagA'")
public void rocketmqMsgListen(RocketmqEvent event) {
DefaultMQPushConsumer consumer = event.getConsumer();
try {
System.out.println("com.bqjr.consumerDemo监听到一个消息达到:" + event.getMsg("gbk"));
//TODO 进行业务处理
} catch (Exception e) {
if(event.getMessageExt().getReconsumeTimes()<=3){//重复消费3次
try {
consumer.sendMessageBack(event.getMessageExt(), 2);
} catch (Exception e1) {
//TODO 消息消费失败,进行日志记录
}
} else {
//TODO 消息消费失败,进行日志记录
}
}
}
}
来,测试一把
在浏览器中访问:http://10.89.0.144:12306/sendMsg,控制台输出如下:再测试一下消费者,在RocketMQ控制台(RocketMQ控制台的介绍放到下一篇吧)发送一条消息
补充说明:
本来想自定义一个叫RocketmqListener的注解来实现消息的监听的,花了大量时间去阅读和研究了spring关于EventListener注解和JmsListener注解的实现,发现目前我并不能很好的理解和掌控其设计思路,想以瓢画葫最终也没能实现,迫于五一节来临,只能使用EventListener注解代替,不过发现其实也不错。
同时,也希望各位猿友能给出指导性意见和建议:如何实现RocketmqListener注解以及是否有意义?