Spring Cloud Stream消息驱动之RocketMQ入门（一）

SpringCloudStream目前支持的中间件有RabbitMQ、Kafka，还有我最近在学习的RocketMQ,以下是我学习的笔记
学习Spring cloud Stream 可以先学习一下了解 Spring Messaging 和 Spring Integration，

先看看Spring Message 消息的模型

Messaging 对应的模型就包括一个消息体 Payload 和消息头 Header

消息通道 MessageChannel 用于接收消息，调用 send 方法可以将消息发送至该消息通道中，直接撸demo吧

pom.xml 依赖

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.2.2.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>cloud-stream-rocketmq-demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>cloud-stream-rocketmq-demo</name>
<description>Demo project for Spring Boot</description>

<properties>
<java.version>1.8</java.version>
</properties>

<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-stream</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-stream-binder-rocketmq</artifactId>
<version>0.2.1.RELEASE</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>Hoxton.SR1</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>

</project>

@EnableBinding：该注解用来指定一个或多个定义了@Input或@Output注解的接口，以此实现对消息通道（Channel）的绑定
@StreamListener：该注解主要定义在方法上，作用是将被修饰的方法注册为消息中间件上数据流的事件监听器，注解中的属性值对应了监听的消息通道名

@Component
@EnableBinding(StreamInput.class)
@Slf4j
public class ReceiveClient {

@StreamListener(StreamInput.input)
public void receive01(String message){
log.info("接收消息："+message);
}

}

@Input注解绑定了一个名为input的通道

public interface StreamInput {

String input = "input";

@Input(StreamInput.input)
SubscribableChannel input();
}

@Output注解绑定了一个名为Output的通道

public interface StreamInput {

String input = "input";

@Input(StreamInput.input)
SubscribableChannel input();
}

测试一下
启动类加上刚刚添加的两个接口
@EnableBinding({StreamInput.class, StreamOutput.class})

@Autowired
private StreamOutput streamOutput;

@GetMapping("/send")
public String send(){
MessageBuilder builder = MessageBuilder.withPayload("测试消息".getBytes());
streamOutput.output().send(builder.build());
return "ok";
}

不要忘记@EnableBinding注解绑定