Whitelabel Error Page
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Sun Feb 13 16:33:34 CST 2022
There was an unexpected error (type=Internal Server Error, status=500).
[404] during [GET] to [http://SPRINGCLOUD-DEP-PROVIDER/dep/get/8] [DeptService#queryDepById(int)]: [{"timestamp":"2022-02-13T08:33:34.858+00:00","status":404,"error":"Not Found","message":"No message available","path":"/dep/get/8"}]
feign.FeignException$NotFound: [404] during [GET] to [http://SPRINGCLOUD-DEP-PROVIDER/dep/get/8] [DeptService#queryDepById(int)]: [{"timestamp":"2022-02-13T08:33:34.858+00:00","status":404,"error":"Not Found","message":"No message available","path":"/dep/get/8"}]

引起错误的原因就是因为 ：Feign的接口 和服务的接口不对应导致的 

Api层接口是这样的

@Component
@FeignClient(value = "SPRINGCLOUD-DEP-PROVIDER")
public interface DeptService {

    @RequestMapping("/dep/del/{id}")
    int deleteDep(@PathVariable(name = "id") int id);

    @RequestMapping("/dep/get")
    List<Dep> queryAllDep();

    @RequestMapping("/dep/get/{id}")
    Dep queryDepById(@PathVariable(name = "id") int id);
}

Feign层接口是这样的

 @RequestMapping("/custom/dep/get/{id}")
    public Dep getDepById(@PathVariable("id") int id){
        return this.deptService.queryDepById(id);
    }

    @RequestMapping("/custom/dep/get")
    public List<Dep> getDep(){
        return this.deptService.queryAllDep();
    }

    @RequestMapping("/custom/dep/del/{id}")
    public int delDep(@PathVariable("id") int id){
        return this.deptService.deleteDep(id);
    }

服务层接口必须与其对应才能访问到  

@GetMapping("/dep/get")
    public List<Dep> getAllDep(){
        return depService.queryAllDep();
    }

    @GetMapping("/dep/get/{id}")
    public Dep getDep(@PathVariable("id") int id){
        return depService.queryDepById(id);
    }

我是因为服务层接口与Feign层接口不对应导致了报错，要确保 API层和Service层的url接口一致，不然就会出现报错。

 项目结构如图： 调用的大致流程是：客户端调用API层，API层再去调用服务层，

需要确保API层和服务层的url接口一致。