Question

我们在我们的Spring Boot应用程序（Spring Boot 2.1.2.RELEASE）中使用 Spring-Kafka 2.2.3.RELEASE ，并且在该应用程序中我们将一些kafka使用者定义为

@Component
@RefreshScope
@ConditionalOnProperty(prefix = "ord", value = "order-event.messaging.consumer.enabled", havingValue = "true")
public class OrderEventListener {

    @KafkaListener(id = "orderEventListener", topics = "#{'${order.consumer.topic}'}")
    public void consumeMessageEvent(OrderEvent messageEvent,ConsumerRecord<String, ?> record) { 

    // do some further processing.

    } 

}

现在让我们跳到这个问题，

因此，当我启动应用程序时，在应用程序启动本身上，它会激活此使用者并尝试连接到代理，但是代理未在我的系统中启动并运行，并且在超时后会引发错误

创建名称为'scopedTarget.orderEventListener'的bean时出错

并显示“应用程序运行失败”并终止该过程。

为什么要求代理在启动时启动并运行应用程序？
以前，我们使用的是 Spring Kafka 1.1.8.RELEASE ，它以前可以正常运行，而无需启动代理和用于正常启动的应用程序。

是预期行为吗？因此行为从1.1.8更改为2.2.3？

其他日志，

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'scopedTarget.orderEventListener' Initialization of bean failed; nested exception is org.apache.kafka.common.errors.TimeoutException: Timeout expired while fetching topic metadata
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:584) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:498) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$1(AbstractBeanFactory.java:356) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
    at org.springframework.cloud.context.scope.GenericScope$BeanLifecycleWrapper.getBean(GenericScope.java:390) ~[spring-cloud-context-2.1.0.RELEASE.jar:2.1.0.RELEASE]
    at org.springframework.cloud.context.scope.GenericScope.get(GenericScope.java:184) ~[spring-cloud-context-2.1.0.RELEASE.jar:2.1.0.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:353) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1083) ~[spring-context-5.1.4.RELEASE.jar:5.1.4.RELEASE]
    at org.springframework.cloud.context.scope.refresh.RefreshScope.eagerlyInitialize(RefreshScope.java:130) ~[spring-cloud-context-2.1.0.RELEASE.jar:2.1.0.RELEASE]
    at org.springframework.cloud.context.scope.refresh.RefreshScope.start(RefreshScope.java:121) ~[spring-cloud-context-2.1.0.RELEASE.jar:2.1.0.RELEASE]
    at org.springframework.cloud.context.scope.refresh.RefreshScope.onApplicationEvent(RefreshScope.java:115) ~[spring-cloud-context-2.1.0.RELEASE.jar:2.1.0.RELEASE]
    at org.springframework.cloud.context.scope.refresh.RefreshScope.onApplicationEvent(RefreshScope.java:71) ~[spring-cloud-context-2.1.0.RELEASE.jar:2.1.0.RELEASE]
    at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172) ~[spring-context-5.1.4.RELEASE.jar:5.1.4.RELEASE]
    at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165) ~[spring-context-5.1.4.RELEASE.jar:5.1.4.RELEASE]
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139) ~[spring-context-5.1.4.RELEASE.jar:5.1.4.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:398) ~[spring-context-5.1.4.RELEASE.jar:5.1.4.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:355) ~[spring-context-5.1.4.RELEASE.jar:5.1.4.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:882) ~[spring-context-5.1.4.RELEASE.jar:5.1.4.RELEASE]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.finishRefresh(ServletWebServerApplicationContext.java:163) ~[spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:549) ~[spring-context-5.1.4.RELEASE.jar:5.1.4.RELEASE]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:142) ~[spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:775) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:316) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1260) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1248) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE]
    at oal.oracle.apps.ic.coll.ordsbx.Application.main(Application.java:59) [classes/:?]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_161]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_161]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_161]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_161]
    at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) [spring-boot-devtools-2.1.2.RELEASE.jar:2.1.2.RELEASE]
Caused by: org.apache.kafka.common.errors.TimeoutException: Timeout expired while fetching topic metadata

Answer 1

这是由于对基础kafka-clients库的更改（自2.0.0起）。

以前，它将永远阻塞，使应用程序完全不受控制，这对于许多用户来说是无法接受的。

现在，如果代理不可用，该操作将超时。

我不确定为什么在创建bean时会失败-仅在应用程序生命周期中稍后start()装入容器时才会发生。但是我看到您使用的是devtools，所以我不确定它是否会加剧问题-编辑问题以显示 complete 堆栈跟踪记录（您应该从不从此处截断堆栈跟踪记录，因为我们看不到完整的故事。

通常，可以通过将autoStartup设置为false，然后稍后自己循环启动容器，等待代理存在，来避免这种情况。

在Spring Kafka 2.2.3的Spring Boot应用程序启动之前，Kafka侦听器处于活动状态。

1 个答案: