[RESTful Web Service]-4

RESTfulサービス機能の拡張

Validation API

依存項目の追加

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-validation</artifactId>
            <version>2.5.6</version>
        </dependency>

    @Size(min = 2, message = "Name은 2글자 이상")
    private String name;
    @Past
    private Date joinDate;

@PostMapping("/users")
    public ResponseEntity<User> createUser(@Valid @RequestBody User user)

@RestControllerAdvice
public class CustomizedResponseEntityExceptionHandler extends ResponseEntityExceptionHandler {
//...

    @Override
    protected ResponseEntity<Object> handleMethodArgumentNotValid(MethodArgumentNotValidException ex, HttpHeaders headers, HttpStatus status, WebRequest request) {

        ExceptionResponse exceptionResponse = new ExceptionResponse(new Date(),
                "Validation Failed", ex.getBindingResult().toString());
        return new ResponseEntity(exceptionResponse, HttpStatus.BAD_REQUEST);
    }
}

マルチ言語処理

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

HelloWorldController

public class HelloWorldController {

    @Autowired 
    private MessageSource messageSource;
    //...
        @GetMapping(path = "/hello-world-internationalized")
    public String helloWorldInternationalized(@RequestHeader(name = "Accept-Language", required = false) Locale locale){

        return messageSource.getMessage("greeting.message", null, locale);
    }
}

application.yml

spring:
  messages:
    basename: messages

messages.properties(default, en, fr)

greeting.message = 안녕하세요

greeting.message = Hello

greeting.message = Bonjour

レスポンスデータフォーマットの変換(XML)

依存項目の追加

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

レスポンスデータ制御(Filtering)

    @JsonIgnore //외부에 노출시키지 않음
    private String password;
    @JsonIgnore
    private String ssn;

@JosonIgnoreなし

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

プログラミング制御のフィルタリング

個々のユーザーの表示

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

@RestController
@RequestMapping("/admin")
public class AdminUserController {
//...

    @GetMapping("/users/{id}")
    public MappingJacksonValue retrieveUser(@PathVariable int id) {
        User user = service.findOne(id);

        if (user == null) {
            throw new UserNotFoundException(String.format("ID[%s] not found", 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;
    }
}

すべてのユーザーの表示

    @GetMapping("/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;
    }

URIを使用してREST APIバージョンを管理する

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

public class AdminUserController {
//...
    @GetMapping("/v2/users/{id}")
    public MappingJacksonValue retrieveUserV2(@PathVariable int id) {
        User user = service.findOne(id);

        if (user == null) {
            throw new UserNotFoundException(String.format("ID[%s] not found", id));
        }

        UserV2 userV2 = new UserV2();
        BeanUtils.copyProperties(user, userV2);
        userV2.setGrade("VIP");

        SimpleBeanPropertyFilter filter = SimpleBeanPropertyFilter
                .filterOutAllExcept("id", "name", "joinDate", "grade"); //포함하는 것

        FilterProvider filters = new SimpleFilterProvider().addFilter("UserInfoV2", filter);

        MappingJacksonValue mapping = new MappingJacksonValue(userV2);
        mapping.setFilters(filters);

        return mapping;
    }
}

Request Parameterによるバージョン管理

    @GetMapping(value = "/users/{id}/", params = "version=1")
    public MappingJacksonValue retrieveUserV1(@PathVariable int id) {
    //...
    }

    @GetMapping(value = "/users/{id}/", params = "version=2")
    public MappingJacksonValue retrieveUserV2(@PathVariable int id) {
    //...
    }

Headerによるバージョン管理

    @GetMapping(value = "/users/{id}", headers = "X-API-VERSION=1")
    public MappingJacksonValue retrieveUserV1(@PathVariable int id){
    //...
    }
    @GetMapping(value = "/users/{id}", headers = "X-API-VERSION=2")
    public MappingJacksonValue retrieveUserV2(@PathVariable int id){
    //...
    }

MIMEタイプを使用したバージョン管理

    @GetMapping(value = "/users/{id}", produces = "application/vnd.company.appv1+json")
    public MappingJacksonValue retrieveUserV1(@PathVariable int id){
    //...
    }
    @GetMapping(value = "/users/{id}", produces = "application/vnd.company.appv2+json")
    public MappingJacksonValue retrieveUserV2(@PathVariable int id){
    //...
    }