FeignClient报错The bean 'item-service.FeignClientSpecification' could not be registered. A bean with that name has already been defined and overriding is disabled.

FeignClient启动报错

The bean 'item-service.FeignClientSpecification' could not be registered. A bean with that name has already been defined and overriding is disabled.

报错原因：

在Spring Boot 2.0.x 中，spring.main.allow-bean-definition-overriding属性默认是 true，注解@FeignClient 没有contextId属性；

在Spring Boot 2.1.x 中，spring.main.allow-bean-definition-overriding属性默认是 false，注解@FeignClient 有contextId属性；

解决方法：

方法1：application.yml添加allow-bean-definition-overriding: true

spring:
  main:
    allow-bean-definition-overriding: true

方法2：为每个Client手动指定不同的contextId，如contextId = "brandFeignClient"

@FeignClient(name = "item-service",contextId = "brandFeignClient")
public interface BrandClient extends BrandApi {
}