排错feign.FeignException$NotFound: [404]

完整错误如下
feign.FeignException$NotFound: [404] during [GET] to [http://microservice-provider-user/] [UserFeignService#findById(int)]: [{“timestamp”:“2021-04-29T03:02:57.063+00:00”,“status”:404,“error”:“Not Found”,“message”:“No message available”,“path”:"/"}]

配置类

public class FeginConfiguration {
	
	@Bean
	public Contract getContract() {
		return new feign.Contract.Default();
	}

}

Feign服务接口类

@FeignClient(name="microservice-provider-user",configuration = FeginConfiguration.class)
public interface UserFeignService {
	
	@RequestLine("GET /{id}")
	public User findById(@PathVariable("id") int id);
}

将Feign服务修改如下再次访问测试成功。

import feign.Param;
import feign.RequestLine;

@FeignClient(name="microservice-provider-user",configuration = FeginConfiguration.class)
public interface UserFeignService {
	
	@RequestLine("GET /{id}")
	public User findById(@Param("id") int id);
}

修改的内容为将spring web包下的注解PathVariable换成了feign core包下的Param.

分析如下，如果使用PathVariable，那么controller传过来的id,就无法传递给feign的注解RequestLine.
那么Fegin最终组装的URL就是Get请求的http://microservice-provider-user/，因为id无法传递给RequestLine, 那么/{id}，就会解析成 / .
这里Param和RequestLine需要配套使用