RestFul Service 기능 확장

Validation

• JDK에 포함된 Validation API
• Hibernate library에 포함된 Hibernate Validation

import javax.validation.constraints.*;

controller

@PostMapping("/")
public ResponseEntity<> create(@Valid @RequestBody User user){ 
	return ResponseEntity.status(HttpStatus.CREATED).body(responseUser);}

@RestController
@ControllerAdvice
public class CustomizedResponseEntityExceptionHandler extends ResponseEntityExceptionHandler {

    //유효성 검사에 문제가 생겼을 때 화면에 오류 메세지를 출력하기 위한
    @Override
    protected ResponseEntity<Object> handleMethodArgumentNotValid(
            MethodArgumentNotValidException ex,
            HttpHeaders headers, HttpStatus status,
            WebRequest request) {
        ExceptionResponse exceptionResponse = new ExceptionResponse(new Date(),
                ex.getMessage(), ex.getBindingResult().toString());
        return new ResponseEntity(exceptionResponse, HttpStatus.BAD_REQUEST);
    }

}

Internationalization

다국어 처리

@Bean
public LocaleResolver localeResolver(){
	SessionLocaleResolver localeResolver = new SessionLocaleResolver();
    localeResolver.setDefaultLocale(Locale.KOREA);
    return localeResolver;
}

application.yml

spring:
  messages:
    basename: messages //다국어 파일의 이름을 "messages" 로 하겠다는 의미

resources에 위에 적은 이름으로
messages.properties
greeting.message=안녕하세요
messages_en.properties
greeting.message=Hello
*messages_fr.properties
greeting.message=Bonjour

//메세지소스를 반환하기 위해서
import org.springframework.context.MessageSource;
private final MessageSource messageSource;

@GetMapping("/hello")
public String hello(@RequestHeader(name="Accept-Language", required=false) Locale locale){
	return messageSource.getMessage("greeting.message",null,locale);
}

XML format으로 반환하기

<dependency>
	<groupId>com.faster xml.jackson.dataformat</groupId>
    <artifactId>jackson-dataformat-xml</artifactId>
    <version>2.10.2</version>
</dependency>

Filtering

중요한 데이터를 클라이언트가 바로 받아볼 수 있는 것이 아니라 이런 데이터 값을 제어하는 방법

방법 1.

@JsonIgnore
private String password;

@JsonIgnore
private String ssn;

방법 2.

@JsonIgnoreProperties(value={"password", "ssn"})
public class User{
	...
    private String password;
    private String ssn;
}

개별 사용자 조회 Filtering방법

@JsonFilter("UserInfo")
public class User{
	...
}

관리자 유저컨트롤러

*개인 사용자 보기

@GetMapping("/admin/users/{id}")
public MappingJacksonValue retreveUser(@PathVariable int id){
	SimpleBeanPropertyFilter filter = simpleBeanPropertyFilter.filterOutAllExcept("id", "name" "joinDate" "ssn");
    FilterProvider filters = new SimpleFilterProvider().addFilter("UserInfo", filter);
    MappingJacksonValue mapping = new MappingJacksonValue(user);
    mapping.setFilters(filters);
    
  	return mapping;
}    

*유저 리스트

@GetMapping("/admin/users")
public MappingJacksonValue retrieveAllUsers(){
	List<User users = service.findAll();
    
    SimpleBeanPropertyFilter filter = simpleBeanPropertyFilter.filterOutAllExcept("id", "name" "joinDate" "ssn");
    FilterProvider filters = new SimpleFilterProvider().addFilter("UserInfo", filter);
    MappingJacksonValue mapping = new MappingJacksonValue(users);
    mapping.setFilters(filters);
    
  	return mapping;
    
}

Version관리

UserV1 class

@Data
@AllArgsConstructor
@NoArgsConstructor
@JsonFilter("UserInfo")
public class UserV1{
	private Integer id;
    @Size(min=2, message = "이름은 두글자 이상 입력해주세요.")
    private String name;
    
    @Past
    private Date joinDate;
    
    private String ssn;

UserV2 class

@Data
@AllArgsConstructor
@NoArgsConstructor
@JsonFilter("UserInfoV2")
public class UserV2 extends UserV1 {
	private String grade;
}

@GetMapping("/admin/v2/users/{id}")
public MappingJacksonValue retreveUserV2(@PathVariable int id){
	
    //user -> user2
	UserV2 userV2 = new UserV2();
    BeanUtils.copyProperties(userV1, userV2);
	userV2.setGrade("VIP");


SimpleBeanPropertyFilter filter = simpleBeanPropertyFilter.filterOutAllExcept("id", "name" "joinDate" "ssn", "grade");
    FilterProvider filters = new SimpleFilterProvider().addFilter("UserInfoV2", filter);
    MappingJacksonValue mapping = new MappingJacksonValue(user);
    mapping.setFilters(filters);
    
  	return mapping;
}    

Request Parameter와 Header를 이용한 API Version관리

*Request Parameter

@GetMapping(value= "/users/{id}", params = "version=1")
public MappingJacksonValue retreveUserV1(@PathVariable int id){...}

@GetMapping(value= "/users/{id}", params = "version=2")
public MappingJacksonValue retreveUserV2(@PathVariable int id){...}

*Header

@GetMapping(value = "/users/{id}", headers="X-API-VERSION=1")
public MappingJacksonValue retreveUserV1(@PathVariable int id){...}

mine

@GetMapping(value="/users/{id}", produces = "application/vnd.company.appv1+json")
public MappingJacsonvalue retreveUserV1(@PathVariable int id){...}