在Springboot 1.x中将netflix feign迁移到Springboot 2.x中的openfeign

Question

我尝试将Springboot 1.xy（Brussels-SR12）迁移到我使用的2.xy FeignClients

我更改Maven配置：

<spring-cloud.version>Finchley.RELEASE</spring-cloud.version>

所以

<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-openfeign</artifactId>
<version>2.0.0.RELEASE</version>

我更改所有导入：

import org.springframework.cloud.netflix.feign.EnableFeignClients;

import org.springframework.cloud.netflix.feign.FeignClient;

至

import org.springframework.cloud.openfeign.EnableFeignClients;

import org.springframework.cloud.openfeign.FeignClient;

我使用此接口：

@FeignClient(value = "COMPANY", fallbackFactory = CompanyClientFallbackFactory.class, configuration = FeignConfiguration.class)
public interface CompanyClient extends CompanyApi {
}

当我运行JUnit测试（使用spring上下文）时，我现在遇到此错误（不在Springboot 1.xy和旧的netflix包中）：

The bean 'COMPANY.FeignClientSpecification', defined in null, could not be registered. A bean with that name has already been defined in null and overriding is disabled.

完整跟踪：

java.lang.IllegalStateException: Failed to load ApplicationContext
    at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:125)
    at org.springframework.test.context.support.DefaultTestContext.getApplicationContext(DefaultTestContext.java:108)
    at org.springframework.boot.test.mock.mockito.MockitoTestExecutionListener.postProcessFields(MockitoTestExecutionListener.java:99)
    at org.springframework.boot.test.mock.mockito.MockitoTestExecutionListener.injectFields(MockitoTestExecutionListener.java:79)
    at org.springframework.boot.test.mock.mockito.MockitoTestExecutionListener.prepareTestInstance(MockitoTestExecutionListener.java:54)
    at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:246)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:227)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:289)
...
Caused by: org.springframework.beans.factory.support.BeanDefinitionOverrideException: Invalid bean definition with name 'COMPANY.FeignClientSpecification' defined in null: Cannot register bean definition [Generic bean: class [org.springframework.cloud.openfeign.FeignClientSpecification]; scope=; abstract=false; lazyInit=false; autowireMode=0; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=null; factoryMethodName=null; initMethodName=null; destroyMethodName=null] for bean 'COMPANY.FeignClientSpecification': There is already [Generic bean: class [org.springframework.cloud.openfeign.FeignClientSpecification]; scope=; abstract=false; lazyInit=false; autowireMode=0; dependencyCheck=0; autowireCandidate=true; primary=false; factoryBeanName=null; factoryMethodName=null; initMethodName=null; destroyMethodName=null] bound.
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.registerBeanDefinition(DefaultListableBeanFactory.java:896)
    at org.springframework.cloud.openfeign.FeignClientsRegistrar.registerClientConfiguration(FeignClientsRegistrar.java:355)
    at org.springframework.cloud.openfeign.FeignClientsRegistrar.registerFeignClients(FeignClientsRegistrar.java:155)
    at org.springframework.cloud.openfeign.FeignClientsRegistrar.registerBeanDefinitions(FeignClientsRegistrar.java:83)

Answer 1

那是解决方案：

如果我们要创建多个具有相同名称或URL的伪客户端，以便它们指向同一台服务器，但每个客户端具有不同的自定义配置，则必须使用的contextId属性，@FeignClient以避免这些配置Bean发生名称冲突。

@FeignClient(contextId = "fooClient", name = "stores", configuration = FooConfiguration.class)
public interface FooClient {
    //..
}

@FeignClient(contextId = "barClient", name = "stores", configuration = BarConfiguration.class)
public interface BarClient {
    //..
}

https://github.com/spring-cloud/spring-cloud-openfeign/pull/90/commits/82fa5181fdd2e23e7414521f468ecea88e17d157

Answer 2

如果您不小心使用@EnableFeignClients 注释了多个@Configuration 类，也会发生这种情况

Answer 3

可能您有多个@FeignClient具有相同名称属性的定义。