Spring Cloud Alibaba 异步通信 - RocketMQ 自定义 Binding

灰太狼 2020-05-19 16:26 1506阅读 0赞

#  Spring Cloud Alibaba 异步通信 - RocketMQ 自定义 Binding

## 概述

在实际生产中，我们需要发布和订阅的消息可能不止一种 Topic ，故此时就需要使用自定义 Binding 来帮我们实现多 Topic 的发布和订阅功能

## 生产者

自定义 Output 接口，代码如下：

```java
public interface MySource {
    @Output("output1")
    MessageChannel output1();

@Output("output2")
    MessageChannel output2();
}
```

发布消息的案例代码如下：

```java
@Autowired
private MySource source;

public void send(String msg) throws Exception {
    source.output1().send(MessageBuilder.withPayload(msg).build());
}
```

## 消费者

自定义 Input 接口，代码如下：

```java
public interface MySink {
    @Input("input1")
    SubscribableChannel input1();

@Input("input2")
    SubscribableChannel input2();

@Input("input3")
    SubscribableChannel input3();

@Input("input4")
    SubscribableChannel input4();
}
```

接收消息的案例代码如下：

```java
@StreamListener("input1")
public void receiveInput1(String receiveMsg) {
    System.out.println("input1 receive: " + receiveMsg);
}
```

## Application

配置 Input 和 Output 的 Binding 信息并配合 `@EnableBinding` 注解使其生效，代码如下：

```java
@SpringBootApplication
@EnableBinding({ MySource.class, MySink.class })
public class RocketMQApplication {
	public static void main(String[] args) {
		SpringApplication.run(RocketMQApplication.class, args);
	}
}
```

## application.yml

### 生产者

```yaml
spring:
  application:
    name: rocketmq-provider
  cloud:
    stream:
      rocketmq:
        binder:
          namesrv-addr: 192.168.10.149:9876
      bindings:
        output1: {destination: test-topic1, content-type: application/json}
        output2: {destination: test-topic2, content-type: application/json}
```

### 消费者

```yaml
spring:
  application:
    name: rocketmq-consumer
  cloud:
    stream:
      rocketmq:
        binder:
          namesrv-addr: 192.168.10.149:9876
        bindings:
          input: {consumer.orderly: true}
      bindings:
        input1: {destination: test-topic1, content-type: text/plain, group: test-group, consumer.maxAttempts: 1}
        input2: {destination: test-topic1, content-type: text/plain, group: test-group, consumer.maxAttempts: 1}
        input3: {destination: test-topic2, content-type: text/plain, group: test-group, consumer.maxAttempts: 1}
        input4: {destination: test-topic2, content-type: text/plain, group: test-group, consumer.maxAttempts: 1}
```