java - 将 Hystrix 和 Feign 添加到 Spring Boot 项目

Question

我正在尝试将 Feign 和 Hystrix 添加到我现有的 Spring Boot 项目中。

我将这两个依赖项添加到 pom.xml 中:

    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-hystrix</artifactId>
        <version>${spring-cloud.version}</version>
    </dependency>

    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-feign</artifactId>
        <version>${spring-cloud.version}</version>
    </dependency>

项目编译，但是当我启动服务器时，出现此异常:

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.cloud.netflix.feign.ribbon.FeignRibbonClientAutoConfiguration$OkHttpConfiguration': Post-processing failed of bean type [class org.springframework.cloud.netflix.feign.ribbon.FeignRibbonClientAutoConfiguration$OkHttpConfiguration$$EnhancerBySpringCGLIB$$3ecc7446] failed; nested exception is java.lang.IllegalStateException: Failed to introspect bean class [org.springframework.cloud.netflix.feign.ribbon.FeignRibbonClientAutoConfiguration$OkHttpConfiguration$$EnhancerBySpringCGLIB$$3ecc7446] for persistence metadata: could not find class that it depends on
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyMergedBeanDefinitionPostProcessors(AbstractAutowireCapableBeanFactory.java:945) ~[spring-beans-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:518) ~[spring-beans-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482) ~[spring-beans-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:751) ~[spring-beans-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:861) ~[spring-context-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:541) ~[spring-context-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:122) ~[spring-boot-1.4.1.RELEASE.jar:1.4.1.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:761) [spring-boot-1.4.1.RELEASE.jar:1.4.1.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:371) [spring-boot-1.4.1.RELEASE.jar:1.4.1.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) [spring-boot-1.4.1.RELEASE.jar:1.4.1.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1186) [spring-boot-1.4.1.RELEASE.jar:1.4.1.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1175) [spring-boot-1.4.1.RELEASE.jar:1.4.1.RELEASE]
at com.ifood.next.NextApplication.main(NextApplication.java:27) [classes/:?]

Caused by: java.lang.ClassNotFoundException: com.squareup.okhttp.OkHttpClient
at java.net.URLClassLoader.findClass(URLClassLoader.java:381) ~[?:1.8.0_101]
at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.8.0_101]
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331) ~[?:1.8.0_101]
at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.8.0_101]
at java.lang.Class.getDeclaredFields0(Native Method) ~[?:1.8.0_101]
at java.lang.Class.privateGetDeclaredFields(Class.java:2583) ~[?:1.8.0_101]
at java.lang.Class.getDeclaredFields(Class.java:1916) ~[?:1.8.0_101]
at org.springframework.util.ReflectionUtils.getDeclaredFields(ReflectionUtils.java:713) ~[spring-core-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.util.ReflectionUtils.doWithLocalFields(ReflectionUtils.java:655) ~[spring-core-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.buildPersistenceMetadata(PersistenceAnnotationBeanPostProcessor.java:418) ~[spring-orm-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.findPersistenceMetadata(PersistenceAnnotationBeanPostProcessor.java:397) ~[spring-orm-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.orm.jpa.support.PersistenceAnnotationBeanPostProcessor.postProcessMergedBeanDefinition(PersistenceAnnotationBeanPostProcessor.java:333) ~[spring-orm-4.3.3.RELEASE.jar:4.3.3.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyMergedBeanDefinitionPostProcessors(AbstractAutowireCapableBeanFactory.java:940) ~[spring-beans-4.3.3.RELEASE.jar:4.3.3.RELEASE]
... 16 more

我尝试过版本1.1.5.RELEASE和1.2.3.RELEASE，都给我同样的错误。

很明显，它依赖于旧版本的 OKHttp？当前版本是com.squareup.okhttp3.OkHttpClient

我是否缺少更多依赖项？很难找到这些模块的示例和教程，因为它们相当新。

Answer 1

Spring Cloud Feign 似乎使用了 OpenFeign，在本次提交 ( https://github.com/OpenFeign/feign/commit/3d84c767ba464b2a75e3e1e6c002b0173da268f1 ) 中，OpenFeign 已升级为使用 OkHttp3。您可以尝试强制使用新版本的 https://github.com/OpenFeign/feign看看是否有帮助。

查看 https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-ribbon/1.2.3.RELEASE 的依赖关系似乎使用的是 Netflix Libraries 的 2.2.0 版本，它于 2016 年 4 月发布 - 比 OkHttp 升级到版本 3 的提交早了一个月。

尝试强制使用2.2.2版本。