如何使用 Feign Client Spring Boot 从另一个服务获取数据（错误：406）

Question

当我使用 Feign Client 从一个服务（API 网关）调用另一个服务（用户服务）时，出现错误

有两种服务

1. 用户服务
2. API网关

在我的 API 网关中

假客户端

@FeignClient(contextId = "user-by-email",name = "user-service")
@Service
public interface UserByEmail {
    @RequestMapping(value = "/email/{email}", consumes= MediaType.APPLICATION_JSON_VALUE)
    User findByEmail(@PathVariable("email") String email);
}

控制器

@RequestMapping("/test")
public class TestController {
    @Autowired
    private UserByEmail userByEmail;

    @GetMapping(value = "/{email:.+}")
    public ResponseEntity testUser(@PathVariable("email") String username) {
        return ResponseEntity.ok(userByEmail.findByEmail(username));
    }
}

我需要调用以下（用户服务）

控制器

@EnableFeignClients
@RestController
public class UserController extends BaseController<User> {
    @Autowired
    private UserService userService;

    @PostConstruct
    public void binder() {
        init(this.userService);
    }

    @GetMapping(value = "/email/{email}")
    public ResponseEntity findByEmail(@PathVariable("email") String email) {
        return ResponseEntity.ok(userService.findByEmail(email));
    }
}

存储库

@Override
public User findByEmail(String email) {
  Query query = new Query(Criteria.where("email").is(email).and("status").is(1));
  return mongoOperations.findOne(query, User.class);
}

服务

@Override
public User findByEmail(String email) {
  return userDao.findByEmail(email);
}

我得到的错误是..

<Map>
    <timestamp>1583924335777</timestamp>
    <status>406</status>
    <error>Not Acceptable</error>
    <message>Could not find acceptable representation</message>
    <trace>org.springframework.web.HttpMediaTypeNotAcceptableException: Could not find acceptable representation&#xd;
    at org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters(AbstractMessageConverterMethodProcessor.java:246)&#xd;

任何人都可以解释我的代码有什么问题，并提供您宝贵的解决方案

（基本上我需要在API网关中创建Security，以控制其他服务的访问）

Answer 1

尝试实现 Feign 客户端如下：

@FeignClient(name = "user-service")
public interface UserByEmail {

 @RequestMapping(method = RequestMethod.GET, value = "/email/{email}", consumes = "application/json")
 User findByEmail(@PathVariable("email") String email);

 }

还要确保字段通过 JSON 匹配器User POJO。

Answer 2

我有我的问题的解决方案

假客户端

@FeignClient(contextId = "user-by-email",name = "user-service")
@Service
public interface UserByEmail {
    @RequestMapping(value = "/email/{email}", consumes= MediaType.APPLICATION_JSON_VALUE)
    User findByEmail(@RequestParam("email") String email);
}

控制器

@RequestMapping("/test")
public class TestController {
    @Autowired
    private UserByEmail userByEmail;

    @GetMapping(value = "/{email}")
    public ResponseEntity testUser(@RequestParam("email") String username) {
        return ResponseEntity.ok(userByEmail.findByEmail(username));
    }
}

在用户服务中

控制器

@EnableFeignClients
@RestController
public class UserController extends BaseController<User> {
    @Autowired
    private UserService userService;

    @PostConstruct
    public void binder() {
        init(this.userService);
    }

    @GetMapping(value = "/email/{email}")
    public ResponseEntity findByEmail(@RequestParam("email") String email) {
        return ResponseEntity.ok(userService.findByEmail(email));
    }
}