简而言之:
构建一个非常基本的 Eureka Discovery 服务器 spring boot 2.0.4。还创建了一个使用 Eureka 发现的基本 Eureka 服务。启动发现服务器，然后启动服务。该服务向发现服务器注册，但随后立即取消注册并停止。
详细信息发现服务器代码:
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
@SpringBootApplication
@EnableEurekaServer
public class DiscoveryServerApplication {
public static void main(String[] args) {
SpringApplication.run(DiscoveryServerApplication.class, args);
}
}
服务:请注意，在本示例中，我将 Controller 放置在主启动应用程序中。
@EnableDiscoveryClient //Want it to registger with the discovery
@SpringBootApplication
@RestController //Obviously not a best practice just an example
public class ServiceApplication {
public static void main(String[] args) {
SpringApplication.run(ServiceApplication.class, args);
}
@Value("${spring.application.name")
private String instance;
@RequestMapping("/")
public String message() {
return "hello from " + instance;
}
}
服务pom.xml:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.skjenco</groupId>
<artifactId>service</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>service</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.4.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
<spring-cloud.version>Finchley.SR1</spring-cloud.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-actuator</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>4.3.4.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</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>
问题: 该服务将注册，但随后会取消注册。
2018-09-07 22:18:23.918 INFO 9660 --- [ restartedMain] com.netflix.discovery.DiscoveryClient : Getting all instance registry info from the eureka server
2018-09-07 22:18:24.011 INFO 9660 --- [ restartedMain] com.netflix.discovery.DiscoveryClient : The response status is 200
2018-09-07 22:18:24.014 INFO 9660 --- [ restartedMain] com.netflix.discovery.DiscoveryClient : Starting heartbeat executor: renew interval is: 30
2018-09-07 22:18:24.016 INFO 9660 --- [ restartedMain] c.n.discovery.InstanceInfoReplicator : InstanceInfoReplicator onDemand update allowed rate per min is 4
2018-09-07 22:18:24.019 INFO 9660 --- [ restartedMain] com.netflix.discovery.DiscoveryClient : Discovery Client initialized at timestamp 1536380304018 with initial instances count: 0
2018-09-07 22:18:24.022 INFO 9660 --- [ restartedMain] o.s.c.n.e.s.EurekaServiceRegistry : Registering application service with eureka with status UP
2018-09-07 22:18:24.023 INFO 9660 --- [ restartedMain] com.netflix.discovery.DiscoveryClient : Saw local status change event StatusChangeEvent [timestamp=1536380304023, current=UP, previous=STARTING]
2018-09-07 22:18:24.025 INFO 9660 --- [nfoReplicator-0] com.netflix.discovery.DiscoveryClient : DiscoveryClient_SERVICE/325L:service:8081: registering service...
2018-09-07 22:18:24.041 INFO 9660 --- [ restartedMain] com.skjenco.service.ServiceApplication : Started ServiceApplication in 4.053 seconds (JVM running for 4.947)
2018-09-07 22:18:24.046 INFO 9660 --- [ Thread-19] s.c.a.AnnotationConfigApplicationContext : Closing org.springframework.context.annotation.AnnotationConfigApplicationContext@7fb5981d: startup date [Fri Sep 07 22:18:21 MDT 2018]; parent: org.springframework.context.annotation.AnnotationConfigApplicationContext@47583a40
2018-09-07 22:18:24.047 INFO 9660 --- [ Thread-19] o.s.c.n.e.s.EurekaServiceRegistry : Unregistering application service with eureka with status DOWN
2018-09-07 22:18:24.047 WARN 9660 --- [ Thread-19] com.netflix.discovery.DiscoveryClient : Saw local status change event StatusChangeEvent [timestamp=1536380304047, current=DOWN, previous=UP]
2018-09-07 22:18:24.049 INFO 9660 --- [ Thread-19] o.s.c.support.DefaultLifecycleProcessor : Stopping beans in phase 0
2018-09-07 22:18:24.051 INFO 9660 --- [ Thread-19] o.s.j.e.a.AnnotationMBeanExporter : Unregistering JMX-exposed beans on shutdown
2018-09-07 22:18:24.052 INFO 9660 --- [ Thread-19] o.s.j.e.a.AnnotationMBeanExporter : Unregistering JMX-exposed beans
2018-09-07 22:18:24.053 INFO 9660 --- [ Thread-19] com.netflix.discovery.DiscoveryClient : Shutting down DiscoveryClient ...
2018-09-07 22:18:24.055 WARN 9660 --- [ Thread-19] .s.c.a.CommonAnnotationBeanPostProcessor : Invocation of destroy method failed on bean with name 'scopedTarget.eurekaClient': org.springframework.beans.factory.BeanCreationNotAllowedException: Error creating bean with name 'eurekaInstanceConfigBean': Singleton bean creation not allowed while singletons of this factory are in destruction (Do not request a bean from a BeanFactory in a destroy method implementation!)
调试时，您可以在创建配置 bean 时看到错误。
org.springframework.beans.factory.BeanCreationNotAllowedException: Error creating bean with name 'eurekaInstanceConfigBean': Singleton bean creation not allowed while singletons of this factory are in destruction (Do not request a bean from a BeanFactory in a destroy method implementation!)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:208) [spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:315) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:251) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1135) [spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1062) [spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:818) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.resolvePreparedArguments(ConstructorResolver.java:767) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:410) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1247) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1096) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:535) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:495) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$1(AbstractBeanFactory.java:353) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.cloud.context.scope.GenericScope$BeanLifecycleWrapper.getBean(GenericScope.java:390) [spring-cloud-context-2.0.1.RELEASE.jar:2.0.1.RELEASE]
at org.springframework.cloud.context.scope.GenericScope.get(GenericScope.java:184) [spring-cloud-context-2.0.1.RELEASE.jar:2.0.1.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:350) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.aop.target.SimpleBeanTargetSource.getTarget(SimpleBeanTargetSource.java:35) ~[spring-aop-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:672) ~[spring-aop-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at com.netflix.appinfo.ApplicationInfoManager$$EnhancerBySpringCGLIB$$9150922a.unregisterStatusChangeListener(<generated>) ~[eureka-client-1.9.3.jar:1.9.3]
at com.netflix.discovery.DiscoveryClient.shutdown(DiscoveryClient.java:891) ~[eureka-client-1.9.3.jar:1.9.3]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_111]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_111]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_111]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_111]
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleElement.invoke(InitDestroyAnnotationBeanPostProcessor.java:366) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor$LifecycleMetadata.invokeDestroyMethods(InitDestroyAnnotationBeanPostProcessor.java:324) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.postProcessBeforeDestruction(InitDestroyAnnotationBeanPostProcessor.java:156) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.DisposableBeanAdapter.destroy(DisposableBeanAdapter.java:240) [spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.DisposableBeanAdapter.run(DisposableBeanAdapter.java:233) [spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.cloud.context.scope.GenericScope$BeanLifecycleWrapper.destroy(GenericScope.java:404) [spring-cloud-context-2.0.1.RELEASE.jar:2.0.1.RELEASE]
at org.springframework.cloud.context.scope.GenericScope.destroy(GenericScope.java:139) [spring-cloud-context-2.0.1.RELEASE.jar:2.0.1.RELEASE]
at org.springframework.beans.factory.support.DisposableBeanAdapter.destroy(DisposableBeanAdapter.java:256) [spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.destroyBean(DefaultSingletonBeanRegistry.java:571) [spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.destroySingleton(DefaultSingletonBeanRegistry.java:543) [spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.destroySingleton(DefaultListableBeanFactory.java:954) [spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.destroySingletons(DefaultSingletonBeanRegistry.java:504) [spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.destroySingletons(DefaultListableBeanFactory.java:961) [spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.destroyBeans(AbstractApplicationContext.java:1041) [spring-context-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.doClose(AbstractApplicationContext.java:1017) [spring-context-5.0.8.RELEASE.jar:5.0.8.RELEASE]
at org.springframework.context.support.AbstractApplicationContext$1.run(AbstractApplicationContext.java:937) [spring-context-5.0.8.RELEASE.jar:5.0.8.RELEASE]
我的解决方法是不使用最新的 Spring bootinitializr。我改用 1.5.15。
我想将 Spring boot 2^ 与 Spring Cloud 一起使用。
最佳答案
日志行通知:
2018-09-07 22:18:24.046 INFO 9660 --- [ Thread-19] s.c.a.AnnotationConfigApplicationContext : Closing org.springframework.context.annotation.AnnotationConfigApplicationContext@7fb5981d: startup date [Fri Sep 07 22:18:21 MDT 2018]; parent: org.springframework.context.annotation.AnnotationConfigApplicationContext@47583a40
您的应用程序启动后立即停止，这与 Discovery Client 无关。底部的错误日志只是由于应用程序停止而导致Discovery Client停止时的错误。
此问题的根本原因是您的应用程序不是 Web 应用程序，因为它内部没有嵌入式 Tomcat。这是由于其类路径上缺少 Spring boot web 导致的。
解决方案:在您的 pom.xml 文件中添加 Spring boot Web 依赖项:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
干杯!
关于java - Spring Cloud Service 向 Discovery Server 注册，但随后取消注册并停止，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/52232029/