[실습] Elasticsearch를 활용해 CRUD API 만들기

JSCODE 박재성

2026. 04. 04.

심플하게 만들기 위해 Service Layer 없이 Controller만 생성해서 CRUD API를 만들 것이다.

✅ 사용자 생성 API 만들기

1. Controller 틀 만들기

@RestController
@RequestMapping("users")
public class UserController {
  private UserDocumentRepository userDocumentRepository;

  public UserController(UserDocumentRepository userDocumentRepository) {
    this.userDocumentRepository = userDocumentRepository;
  }

  @PostMapping()
  public UserDocument createUser() {
  }
}

 

2. Request DTO 만들기
UserCreateRequestDto

public class UserCreateRequestDto {
  private String id;
  private String name;
  private Long age;
  private Boolean isActive;

  public String getId() {
    return id;
  }

  public String getName() {
    return name;
  }

  public Long getAge() {
    return age;
  }

  public Boolean getIsActive() {
    return isActive;
  }
}

• 참고) 일관성을 위해 메서드명을 getIsActive()라고 지어주자.
 

3. Controller 완성하기

@RestController
@RequestMapping("users")
public class UserController {
  private UserDocumentRepository userDocumentRepository;

  public UserController(UserDocumentRepository userDocumentRepository) {
    this.userDocumentRepository = userDocumentRepository;
  }

  @PostMapping()
  public UserDocument createUser(@RequestBody UserCreateRequestDto requestDto) {
    UserDocument user = new UserDocument(requestDto.getId(), requestDto.getName(), requestDto.getAge(), requestDto.getIsActive());
    return userDocumentRepository.save(user);
  }
}

 

4. Postman으로 테스트해보기

{
    "id": "1",
    "name": "Jaeseong",
    "age": 20,
    "isActive": true
}

{
    "id": "2",
    "name": "JSCODE",
    "age": 25,
    "isActive": false
}

 

✅ 사용자 조회 API 만들기

1. Controller 만들기

@RestController
@RequestMapping("users")
public class UserController {
  private UserDocumentRepository userDocumentRepository;

  public UserController(UserDocumentRepository userDocumentRepository) {
    this.userDocumentRepository = userDocumentRepository;
  }

  @PostMapping()
  public UserDocument createUser(@RequestBody UserCreateRequestDto requestDto) {
    UserDocument user = new UserDocument(requestDto.getId(), requestDto.getName(), requestDto.getAge(), requestDto.getIsActive());
    return userDocumentRepository.save(user);
  }

  @GetMapping()
  public Page<UserDocument> findUsers() {
    return userDocumentRepository.findAll(PageRequest.of(0, 10));
  }

  @GetMapping("/{id}")
  public UserDocument findUserById(@PathVariable String id) {
    return userDocumentRepository.findById(id)
        .orElseThrow(() -> new RuntimeException("존재하지 않는 사용자입니다."));
  }
}

 

2. Postman으로 테스트해보기
GET localhost:8080/users



 
GET localhost:8080/users/1



 
GET localhost:8080/users/2

✅ 사용자 정보 수정 API 만들기

1. Request DTO 만들기
UserUpdateRequestDto

public class UserUpdateRequestDto {
  private String name;
  private Long age;
  private Boolean isActive;

  public String getName() {
    return name;
  }

  public Long getAge() {
    return age;
  }

  public Boolean getIsActive() {
    return isActive;
  }
}

• 참고) 일관성을 위해 메서드명을 getIsActive()라고 지어주자.
 

3. Controller 완성하기

@RestController
@RequestMapping("users")
public class UserController {
  private UserDocumentRepository userDocumentRepository;

  public UserController(UserDocumentRepository userDocumentRepository) {
    this.userDocumentRepository = userDocumentRepository;
  }

  ...

  @PutMapping("/{id}")
  public UserDocument updateUser(@PathVariable String id, @RequestBody UserUpdateRequestDto requestDto) {
    UserDocument existingUser = userDocumentRepository.findById(id)
        .orElseThrow(() -> new RuntimeException("존재하지 않는 사용자입니다."));
    existingUser.setAge(requestDto.getAge());
    existingUser.setName(requestDto.getName());
    existingUser.setIsActive(requestDto.getIsActive());
    return userDocumentRepository.save(existingUser);
  }
}

 

3. Postman으로 테스트해보기

✅ 사용자 삭제 API 만들기

1. Controller 완성하기

@RestController
@RequestMapping("users")
public class UserController {
  private UserDocumentRepository userDocumentRepository;

  public UserController(UserDocumentRepository userDocumentRepository) {
    this.userDocumentRepository = userDocumentRepository;
  }

  ...

  @DeleteMapping("/{id}")
  public void deleteUser(@PathVariable String id) {
    UserDocument user = userDocumentRepository.findById(id)
        .orElseThrow(() -> new RuntimeException("존재하지 않는 사용자입니다."));

    userDocumentRepository.delete(user);
  }
}

 

2. Postman으로 테스트해보기