Spring Cloud入门实战(二)--集成Eureka
前言
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正在入门SpringCloud中，在学习的过程中也正好做个项目练手。这个项目是想做成一个模板，这样之后遇到同规模项目的时候可以拿来就用，版本也好控制。涉及到的中间件会有Eureka、Ribbon、Feign、HyStrix、Zuul、ConfigServer。这一节将项目改装成Spring Cloud并集成Eureka。
版本
SpringBoot：2.2.1.RELEASE
Spring Cloud：Finchley.RS1
Eureka：2.2.1.RELEASE
目录结构
1、如果商品微服务的ip地址发生了变更，订单微服务中的配置文件也需要跟着修改
2、如果商品微服务有多个，那么在订单微服务中又该如何写地址？
因此引入注册中心用来管理接口配置
文章目录
- 前言
- 一、Eureka服务注册中心配置
- 在项目pom文件中加入SpringCloud管理依赖
- 在eureka模块pom中加入eureka依赖
- 创建application.yml
- 配置启动类
- 二、Eureka客户端服务发现配置
- 生产者配置
- 在模块pom下加入依赖
- 在生产者中的application.yml配置以下信息
- 在启动类中增加注解@EnableEurekaClient
- 消费者配置
- 在模块pom下加入依赖
- 在消费者的application中添加client
- 修改消费者的UserController
- 在启动类中添加注解@EnableEurekaClient
- 三、开启eureka服务器和客户端
- 四、总结
一、Eureka服务注册中心配置
在项目pom文件中加入SpringCloud管理依赖
<dependencyManagement>
<dependencies>
<!-- 导入Spring Cloud的依赖管理 -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>Finchley.RS1</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
在eureka模块pom中加入eureka依赖
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!--springboot 整合eureka服务端-->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
<version>2.2.1.RELEASE</version>
</dependency>
</dependencies>
在这一块就卡了很久，会出现以下报错，这个错误到最后我也没解决，之后就换了版本，新建了个maven仓库。
（一）需要注意的是SpringBoot的版本和eureka的版本有关联，比如我原先用的2.2.1的SpringBoot和1.4.3的eureka会有如下报错
（二）不管springcloud还是springboot版本我都换了很多次，都是出现这个问题，新建了个maven仓库就解决了，判断应该是eureka中jersey出现了版本冲突。
2020-04-09 11:05:11.146 INFO 13864 --- [ main] com.hofe.EurekaApplication : No active profile set, falling back to default profiles: default
2020-04-09 11:05:12.091 WARN 13864 --- [ main] o.s.boot.actuate.endpoint.EndpointId : Endpoint ID 'service-registry' contains invalid characters, please migrate to a valid format.
2020-04-09 11:05:12.263 INFO 13864 --- [ main] o.s.cloud.context.scope.GenericScope : BeanFactory id=e29d8b1a-b705-3aaa-acfe-1ff43115d358
2020-04-09 11:05:12.422 INFO 13864 --- [ main] trationDelegate$BeanPostProcessorChecker : Bean 'org.springframework.cloud.autoconfigure.ConfigurationPropertiesRebinderAutoConfiguration' of type [org.springframework.cloud.autoconfigure.ConfigurationPropertiesRebinderAutoConfiguration$$EnhancerBySpringCGLIB$$4b153431] is not eligible for getting processed by all BeanPostProcessors (for example: not eligible for auto-proxying)
2020-04-09 11:05:12.720 INFO 13864 --- [ main] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port(s): 7999 (http)
2020-04-09 11:05:12.733 INFO 13864 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat]
2020-04-09 11:05:12.733 INFO 13864 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet engine: [Apache Tomcat/9.0.27]
2020-04-09 11:05:12.974 INFO 13864 --- [ main] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2020-04-09 11:05:12.975 INFO 13864 --- [ main] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 1811 ms
2020-04-09 11:05:13.069 WARN 13864 --- [ main] c.n.c.sources.URLConfigurationSource : No URLs will be polled as dynamic configuration sources.
2020-04-09 11:05:13.069 INFO 13864 --- [ main] c.n.c.sources.URLConfigurationSource : To enable URLs as dynamic configuration sources, define System property archaius.configurationSource.additionalUrls or make config.properties available on classpath.
2020-04-09 11:05:13.076 INFO 13864 --- [ main] c.netflix.config.DynamicPropertyFactory : DynamicPropertyFactory is initialized with configuration sources: com.netflix.config.ConcurrentCompositeConfiguration@12d1f1d4
2020-04-09 11:05:13.390 ERROR 13864 --- [ main] o.s.b.web.embedded.tomcat.TomcatStarter : Error starting Tomcat context. Exception: org.springframework.beans.factory.BeanCreationException. Message: Error creating bean with name 'jerseyFilterRegistration' defined in class path resource [org/springframework/cloud/netflix/eureka/server/EurekaServerAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.boot.web.servlet.FilterRegistrationBean]: Factory method 'jerseyFilterRegistration' threw exception; nested exception is java.lang.NoClassDefFoundError: com/sun/jersey/spi/container/servlet/ServletContainer
2020-04-09 11:05:13.420 INFO 13864 --- [ main] o.apache.catalina.core.StandardService : Stopping service [Tomcat]
2020-04-09 11:05:13.427 WARN 13864 --- [ main] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.boot.web.server.WebServerException: Unable to start embedded Tomcat
2020-04-09 11:05:13.443 INFO 13864 --- [ main] ConditionEvaluationReportLoggingListener :
Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2020-04-09 11:05:13.457 ERROR 13864 --- [ main] o.s.boot.SpringApplication : Application run failed
org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.boot.web.server.WebServerException: Unable to start embedded Tomcat
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:156) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:544) ~[spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:747) [spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) [spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) [spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) [spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1215) [spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at com.hofe.EurekaApplication.main(EurekaApplication.java:15) [classes/:na]
Caused by: org.springframework.boot.web.server.WebServerException: Unable to start embedded Tomcat
at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:126) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.<init>(TomcatWebServer.java:88) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getTomcatWebServer(TomcatServletWebServerFactory.java:438) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getWebServer(TomcatServletWebServerFactory.java:191) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:180) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:153) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
... 8 common frames omitted
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jerseyFilterRegistration' defined in class path resource [org/springframework/cloud/netflix/eureka/server/EurekaServerAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.boot.web.servlet.FilterRegistrationBean]: Factory method 'jerseyFilterRegistration' threw exception; nested exception is java.lang.NoClassDefFoundError: com/sun/jersey/spi/container/servlet/ServletContainer
at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:645) ~[spring-beans-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:625) ~[spring-beans-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1338) ~[spring-beans-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1177) ~[spring-beans-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:557) ~[spring-beans-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:517) ~[spring-beans-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:323) ~[spring-beans-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:321) ~[spring-beans-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:207) ~[spring-beans-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.boot.web.servlet.ServletContextInitializerBeans.getOrderedBeansOfType(ServletContextInitializerBeans.java:211) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.web.servlet.ServletContextInitializerBeans.getOrderedBeansOfType(ServletContextInitializerBeans.java:202) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.web.servlet.ServletContextInitializerBeans.addServletContextInitializerBeans(ServletContextInitializerBeans.java:96) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.web.servlet.ServletContextInitializerBeans.<init>(ServletContextInitializerBeans.java:85) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.getServletContextInitializerBeans(ServletWebServerApplicationContext.java:253) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.selfInitialize(ServletWebServerApplicationContext.java:227) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.springframework.boot.web.embedded.tomcat.TomcatStarter.onStartup(TomcatStarter.java:53) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5135) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1384) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1374) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[na:1.8.0_144]
at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:134) ~[na:1.8.0_144]
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:909) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:841) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1384) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1374) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at java.util.concurrent.FutureTask.run(FutureTask.java:266) ~[na:1.8.0_144]
at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:134) ~[na:1.8.0_144]
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:909) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:262) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at org.apache.catalina.core.StandardService.startInternal(StandardService.java:421) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:930) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at org.apache.catalina.startup.Tomcat.start(Tomcat.java:459) ~[tomcat-embed-core-9.0.27.jar:9.0.27]
at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:107) ~[spring-boot-2.2.1.RELEASE.jar:2.2.1.RELEASE]
... 13 common frames omitted
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.boot.web.servlet.FilterRegistrationBean]: Factory method 'jerseyFilterRegistration' threw exception; nested exception is java.lang.NoClassDefFoundError: com/sun/jersey/spi/container/servlet/ServletContainer
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185) ~[spring-beans-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:640) ~[spring-beans-5.2.1.RELEASE.jar:5.2.1.RELEASE]
... 53 common frames omitted
Caused by: java.lang.NoClassDefFoundError: com/sun/jersey/spi/container/servlet/ServletContainer
at org.springframework.cloud.netflix.eureka.server.EurekaServerAutoConfiguration.jerseyFilterRegistration(EurekaServerAutoConfiguration.java:184) ~[spring-cloud-netflix-eureka-server-2.1.2.RELEASE.jar:2.1.2.RELEASE]
at org.springframework.cloud.netflix.eureka.server.EurekaServerAutoConfiguration$$EnhancerBySpringCGLIB$$e48e3812.CGLIB$jerseyFilterRegistration$0(<generated>) ~[spring-cloud-netflix-eureka-server-2.1.2.RELEASE.jar:2.1.2.RELEASE]
at org.springframework.cloud.netflix.eureka.server.EurekaServerAutoConfiguration$$EnhancerBySpringCGLIB$$e48e3812$$FastClassBySpringCGLIB$$b02b22.invoke(<generated>) ~[spring-cloud-netflix-eureka-server-2.1.2.RELEASE.jar:2.1.2.RELEASE]
at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:244) ~[spring-core-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:363) ~[spring-context-5.2.1.RELEASE.jar:5.2.1.RELEASE]
at org.springframework.cloud.netflix.eureka.server.EurekaServerAutoConfiguration$$EnhancerBySpringCGLIB$$e48e3812.jerseyFilterRegistration(<generated>) ~[spring-cloud-netflix-eureka-server-2.1.2.RELEASE.jar:2.1.2.RELEASE]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_144]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_144]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_144]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_144]
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154) ~[spring-beans-5.2.1.RELEASE.jar:5.2.1.RELEASE]
... 54 common frames omitted
Caused by: java.lang.ClassNotFoundException: com.sun.jersey.spi.container.servlet.ServletContainer
at java.net.URLClassLoader.findClass(URLClassLoader.java:381) ~[na:1.8.0_144]
at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[na:1.8.0_144]
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:335) ~[na:1.8.0_144]
at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[na:1.8.0_144]
... 65 common frames omitted
进程完成，退出码 1
创建application.yml
server:
port: 7999
spring:
application:
name: eureka-server
eureka:
###客户端调用地址
client:
serviceUrl:
defaultZone: http://localhost:7999/eureka/
###是否将自己注册到Eureka服务中,因为该应用本身就是注册中心，不需要再注册自己（集群的时候为true）
register-with-eureka: false
###是否从Eureka中获取注册信息,因为自己为注册中心,不会在该应用中的检索服务信息
fetch-registry: false
配置启动类
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
/**
* Eureka注册中心
*/
@SpringBootApplication
@EnableEurekaServer
public class EurekaServerApplication {
public static void main(String[] args) {
SpringApplication.run(EurekaServerApplication.class, args);
}
}
启动之后，访问端口，即可登录控制中心
二、Eureka客户端服务发现配置
生产者配置
在模块pom下加入依赖
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
<version>2.2.1.RELEASE</version>
</dependency>
在生产者中的application.yml配置以下信息
生产者中配置
server:
port: 7900
spring:
application:
name: provider-user
eureka:
client:
service-url:
defaultZone: http://localhost:7999/eureka/
在启动类中增加注解@EnableEurekaClient
@SpringBootApplication
@EnableEurekaClient
public class ProviderUserApplication {
public static void main( String[] args ) {
SpringApplication.run(ProviderUserApplication.class, args);
}
}
消费者配置
在模块pom下加入依赖
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-client</artifactId>
<version>2.2.1.RELEASE</version>
</dependency>
在消费者的application中添加client
server:
port: 7901
spring:
application:
name: consume-user
eureka:
client:
service-url:
defaultZone: http://localhost:7999/eureka/
修改消费者的UserController
@Autowired
private EurekaClient eurekaClient;
private RestTemplate restTemplate = new RestTemplate();
@GetMapping("getUserByEureka/{id}")
public User getUser(@PathVariable Long id){
InstanceInfo info = eurekaClient.getNextServerFromEureka("PROVIDER-USER", false);
String homePageUrl = info.getHomePageUrl();
User user = restTemplate.getForObject(homePageUrl+"/user/"+id, User.class);
return user;
}
在启动类中添加注解@EnableEurekaClient
@SpringBootApplication
@EnableEurekaClient
public class ConsumeUserApplicaton {
public static void main( String[] args ) {
SpringApplication.run(ConsumeUserApplicaton.class, args);
}
}
三、开启eureka服务器和客户端
消费者访问自己的端口7901的getUserByEureka/1得到用户信息。
四、总结
版本对应很重要，可以通过https://spring.io/projects/spring-cloud来查看spring-cloud和SpringBoot的对应关系，以及Eureka的依赖包是否会发生冲突。消费者通过EurekaClient的getNextServerFromEureka方法动态获取生产者的url，访问消费者的url/getUserByEureka/1时，会从生产者的url/user/1中获取。
