Question

我正在尝试通过kafka使用spring-cloud-stream。下面是示例代码。但这似乎无能为力。它总是创建一个称为“输出”的主题。但是这些值尚未发布。

application.yaml

spring.cloud.stream:
  function:
    definition: streamSupplier
  bindings:
    streamSupplier-out-0:
      destination: numbers

我的目标是仅仅产生价值。

@SpringBootApplication
@EnableBinding(Source.class)
public class CloudStreamDemoApplication {

    private AtomicInteger atomicInteger = new AtomicInteger();
    public static void main(String[] args) {
        SpringApplication.run(CloudStreamDemoApplication.class, args);
    }

    @Bean
    public Supplier<Integer> streamSupplier(){
        return () -> {
            System.out.println("Publishing : " + atomicInteger.incrementAndGet());
            return atomicInteger.get();
        };
    }
}

依赖性-2.2.6。释放

<dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-webflux</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-kafka</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.kafka</groupId>
        <artifactId>spring-kafka</artifactId>
    </dependency>

Answer 1

您需要从课程中删除@EnableBinding(Source.class)。如果存在，则功能绑定将不会发生。

Answer 2

注释@EnableBinding导致了如上所述的问题。

阅读Spring Docs的以下摘录：

Unlike previous versions of spring-cloud-stream which relied on @EnableBinding and @StreamListener annotations, the above example looks no different then any vanilla spring-boot application. It defines a single bean of type Function and that it is. So, how does it became spring-cloud-stream application? It becomes spring-cloud-stream application simply based on the presence of spring-cloud-stream and binder dependencies and auto-configuration classes on the classpath effectively setting the context for your boot application as spring-cloud-stream application. And in this context beans of type Supplier, Function or Consumer are treated as defacto message handlers triggering binding of to destinations exposed by the provided binder following certain naming conventions and rules to avoid extra configuration.

卡夫卡-春天的云流

2 个答案: