参考程序员DD大佬的文章，自己新建demo学习学习，由于需要消息回执，看到了@SendTo这个注解能够实现，下面开始学习demo，新建两个项目cloud-stream-consumer消费端 和 cloud-stream-consumer 生产端
public interface StreamReceive {
@Input("MQRece")
SubscribableChannel mqReceive();
}
添加一个StreamReceive接口，定义@input通道
@Component
@Slf4j
public class ReceiveListener {
@StreamListener("MQRece")
public byte[] receive(byte[] bytes){
log.info("接受消息："+new String(bytes));
return "ok".getBytes();
}
}
添加消息监听，接受消息定义为byte[]
添加application.properties配置文件信息
spring.cloud.stream.rocketmq.binder.namesrv-addr= 192.168.211.11:9876
spring.cloud.stream.bindings.MQRece.destination=message-topic
spring.cloud.stream.bindings.MQRece.group=rece-group
server.port=19999
为MQRece通道添加主题message-topic，组名rece-group
到此Stream 客户端消费就完成了，本节需要把@SendTo注解用起来，需要新建一个MessageChannel进行产生消息
public interface MsgBackPush {
@Output("back-push")
MessageChannel backPush();
}
然后在ReceiveListener添加@SendTo
@Component
@Slf4j
public class ReceiveListener {
@StreamListener("MQRece")
@SendTo("back-push")
public byte[] receive(byte[] bytes){
log.info("接受消息："+new String(bytes));
return "ok".getBytes();
}
}
新增通道配置application.properties
spring.cloud.stream.bindings.back-push.destination=back-topic
spring.cloud.stream.bindings.back-push.group=back-group
SpringBoot启动类记得添加 @EnableBinding(value = {StreamReceive.class,MsgBackPush.class})
@SpringBootApplication
@EnableBinding(value = {StreamReceive.class,MsgBackPush.class})
public class CloudStreamConsumerApplication {
public static void main(String[] args) {
SpringApplication.run(CloudStreamConsumerApplication.class, args);
}
}
到此，cloud-stream-consumer这个demo就完成了
接下来看看 cloud-stream-producer
public interface StreamPush {
@Output("MQPush")
MessageChannel mqPush();
}
定义一个通道名为MQPush，进行消息生产
public interface ProducerReceive {
@Input("producer-receive")
SubscribableChannel producerReceive();
}
定义一个通道名为producer-receive,进行回执消息的消费
@Component
@Slf4j
public class ProducerListener {
@StreamListener("producer-receive")
public void producerReceive(byte[] bytes){
log.info("come back message:"+new String(bytes));
}
}
具体回执消息处理逻辑，再来看看application.properties
spring.cloud.stream.rocketmq.binder.namesrv-addr= 192.168.214.191:9876
spring.cloud.stream.bindings.MQPush.destination=message-topic
spring.cloud.stream.bindings.MQPush.group=push-group
spring.cloud.stream.bindings.producer-receive.destination=back-topic
spring.cloud.stream.bindings.producer-receive.group=back-group
server.port=20000
为通道设置topic和group，新建一个Http接口测试一下成果
@SpringBootApplication
@EnableBinding(value = {StreamPush.class,ProducerReceive.class})
@RestController
public class CloudStreamProducerApplication {
public static void main(String[] args) {
SpringApplication.run(CloudStreamProducerApplication.class, args);
}
@Autowired
private StreamPush streamPush;
@GetMapping("/sendMessage")
public String sendMessage(){
streamPush.mqPush().send(MessageBuilder.withPayload("message body".getBytes()).build());
return "ok";
}
}
访问http://localhost:20000/sendMessage,结果图如下
cloud-stream-consumer日志输出
cloud-stream-producer日志输出
学习@ServiceActivator这个注解，上面的项目cloud-stream-consumer ReceiveListener类中添加
@Component
@Slf4j
public class ReceiveListener {
@StreamListener("MQRece")
@SendTo("back-push")
public byte[] receive(byte[] bytes){
log.info("接受消息："+new String(bytes));
// 抛出异常
if(1==1){
throw new RuntimeException("Message consumer failed!");
}
return "ok".getBytes();
}
@Autowired
private MsgBackPush msgBackPush;
@ServiceActivator(inputChannel = "message-topic.rece-group.errors")
public void error(Message<?> message){
log.info("消费者消费消息失败："+message);
msgBackPush.backPush().send(MessageBuilder.withPayload("消息消费失败".getBytes()).build());
}
}
通过使用@ServiceActivator(inputChannel = "test-topic.stream-exception-handler.errors")指定了某个通道的错误处理映射。其中，inputChannel的配置中对应关系如下:
- message-topic：消息通道对应的目标（destination，即：spring.cloud.stream.bindings.MQRece.destination的配置）
- rece-group：消息通道对应的消费组（group，即：spring.cloud.stream.bindings.MQRece.group的配置）
访问http://localhost:20000/sendMessage,结果图如下
cloud-stream-consumer日志输出
cloud-stream-producer日志输出
