Spring Cloud Stream对Spring Cloud体系中的Mq进⾏了很好的上层抽象，可以让我们与具体消息中间件解耦合，屏蔽掉了底层具体MQ消息中间件的细节差异，就像Hibernate屏蔽掉了具体数据库（Mysql/Oracle⼀样）。如此⼀来，我们学习、开发、维护MQ都会变得轻松。⽬前Spring Cloud Stream原生⽀持RabbitMQ和Kafka，阿里在这个基础上提供了RocketMQ的支持
简单使用Spring Cloud Stream 构建基于RocketMQ的生产者和消费者
生产者
pom文件中加入依赖
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-stream-rocketmq</artifactId>
<version>2.1.0.RELEASE</version>
</dependency>
</dependencies>
配置文件中增加关于Spring Cloud Stream binder和bindings的配置
spring:
application:
name: zhao-cloud-stream-producer
cloud:
stream:
rocketmq:
binder:
name-server: 127.0.0.1:9876
bindings:
output:
producer:
group: test
sync: true
bindings:
output:
destination: stream-test-topic
content-type: text/plain # 内容格式。这里使用 JSON
其中destination代表生产的数据发送到的topic
然后定义一个channel用于数据发送
import org.springframework.cloud.stream.annotation.Output;
import org.springframework.messaging.MessageChannel;
public interface TestChannel {
@Output("output")
MessageChannel output();
}
最后构造数据发送的接口
@Controller
public class SendMessageController {
@Resource
private TestChannel testChannel;
@ResponseBody
@RequestMapping(value = "send", method = RequestMethod.GET)
public String sendMessage() {
String messageId = UUID.randomUUID().toString();
Message<String> message = MessageBuilder
.withPayload("this is a test:" + messageId)
.setHeader(MessageConst.PROPERTY_TAGS, "test")
.build();
try {
testChannel.output().send(message);
return messageId + "发送成功";
} catch (Exception e) {
return messageId + "发送失败，原因：" + e.getMessage();
}
}
}
消费者
消费者的pom引入与生产者相同，在此不再赘述，配置时需要将stream的output修改为input并修改对应属性
spring:
application:
name: zhao-cloud-stream-consumer
cloud:
stream:
rocketmq:
binder:
name-server: 127.0.0.1:9876
bindings:
input:
consumer:
tags: test
bindings:
input:
destination: stream-test-topic
content-type: text/plain # 内容格式。这里使用 JSON
group: test
另外关于channel的构造也要做同样的修改
import org.springframework.cloud.stream.annotation.Input;
import org.springframework.messaging.SubscribableChannel;
public interface TestChannel {
@Input("input")
SubscribableChannel input();
}
最后我在启动类中对收到的消息进行了监听
@StreamListener("input")
public void receiveInput(@Payload Message message) throws ValidationException {
System.out.println("input1 receive: " + message.getPayload() + ", foo header: " + message.getHeaders().get("foo"));
}
测试结果
file
file
Stream其他特性
消息发送失败的处理
消息发送失败后悔发送到默认的一个“topic.errors"的channel中(topic是配置的destination)。要配置消息发送失败的处理，需要将错误消息的channel打开
消费者配置如下
spring:
application:
name: zhao-cloud-stream-producer
cloud:
stream:
rocketmq:
binder:
name-server: 127.0.0.1:9876
bindings:
output:
producer:
group: test
sync: true
bindings:
output:
destination: stream-test-topic
content-type: text/plain # 内容格式。这里使用 JSON
producer:
errorChannelEnabled: true
在启动类中配置错误消息的Channel信息
@Bean("stream-test-topic.errors")
MessageChannel testoutPutErrorChannel(){
return new PublishSubscribeChannel();
}
新建异常处理service
import org.springframework.integration.annotation.ServiceActivator;
import org.springframework.messaging.Message;
import org.springframework.stereotype.Service;
@Service
public class ErrorProducerService {
@ServiceActivator(inputChannel = "stream-test-topic.errors")
public void receiveProducerError(Message message){
System.out.println("receive error msg :"+message);
}
}
当发生异常时，由于测试类中已经将异常捕获，处理发送异常主要是在这里进行。模拟，应用与rocketMq断开的场景。可见
file
file
消费者错误处理
首先增加配置为
spring:
application:
name: zhao-cloud-stream-producer
cloud:
stream:
rocketmq:
binder:
name-server: 127.0.0.1:9876
bindings:
output:
producer:
group: test
sync: true
bindings:
output:
destination: stream-test-topic
content-type: text/plain # 内容格式。这里使用 JSON
producer:
errorChannelEnabled: true
增加相应的模拟异常的操作
@StreamListener("input")
public void receiveInput(@Payload Message message) throws ValidationException {
//System.out.println("input1 receive: " + message.getPayload() + ", foo header: " + message.getHeaders().get("foo"));
throw new RuntimeException("oops");
}
@ServiceActivator(inputChannel = "stream-test-topic.test.errors")
public void receiveConsumeError(Message message){
System.out.println("receive error msg"+message.getPayload());
}
file
代码地址https://github.com/zhendiao/deme-code/tree/main/zp
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