#23 팔로우 기능

refrigerator/src/main/java/moja/refrigerator/aggregate/user/Follow.java

@@ -0,0 +1,22 @@
+package moja.refrigerator.aggregate.user;
+
+import jakarta.persistence.*;
+import lombok.Data;
+
+@Entity
+@Table(name = "tbl_follow")
+@Data
+public class Follow {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    @Column(name = "follow_pk")
+    private long followPk;
+
+    @ManyToOne
+    @JoinColumn(name = "follower")
+    private User follower;
+
+    @ManyToOne
+    @JoinColumn(name = "following")
+    private User following;
+}

refrigerator/src/main/java/moja/refrigerator/controller/user/UserController.java

@@ -1,10 +1,10 @@
 package moja.refrigerator.controller.user;
 
-import jakarta.servlet.http.HttpServletRequest;
 import moja.refrigerator.dto.user.request.PasswordResetRequest;
 import moja.refrigerator.dto.user.request.PasswordUpdateRequest;
 import moja.refrigerator.dto.user.request.UserCreateRequest;
 import moja.refrigerator.dto.user.request.UserUpdateRequest;
+import moja.refrigerator.service.user.FollowService;
 import moja.refrigerator.service.user.UserService;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
@@ -13,9 +13,11 @@
 @RestController
 public class UserController {
     private final UserService userService;
+    private final FollowService followService;
 
-    public UserController(UserService userService) {
+    public UserController(UserService userService, FollowService followService) {
         this.userService = userService;
+        this.followService = followService;
     }
 
     // 토큰 검증 로직 확인용
@@ -51,4 +53,11 @@ public ResponseEntity<?> updatePassword(@RequestBody PasswordUpdateRequest reque
         userService.updatePassword(request);
         return ResponseEntity.ok().body("비밀번호가 변경되었습니다.");
     }
+
+    // 팔로우 및 언팔로우
+    @PostMapping("/follow/{userPk}")
+    public ResponseEntity<?> toggleFollow(@PathVariable Long userPk) {
+        followService.toggleFollow(userPk);
+        return ResponseEntity.ok().body("팔로우 상태가 변경되었습니다.");
+    }
 }

refrigerator/src/main/java/moja/refrigerator/repository/user/FollowRepository.java

@@ -0,0 +1,12 @@
+package moja.refrigerator.repository.user;
+
+import moja.refrigerator.aggregate.user.Follow;
+import moja.refrigerator.aggregate.user.User;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface FollowRepository extends JpaRepository<Follow, Long> {
+    boolean existsByFollowerAndFollowing(User follower, User following);
+    void deleteByFollowerAndFollowing(User follower, User following);
+}

refrigerator/src/main/java/moja/refrigerator/service/user/FollowService.java

@@ -0,0 +1,5 @@
+package moja.refrigerator.service.user;
+
+public interface FollowService {
+    void toggleFollow(Long targetUserPk);
+}

refrigerator/src/main/java/moja/refrigerator/service/user/FollowServiceImpl.java

@@ -0,0 +1,50 @@
+package moja.refrigerator.service.user;
+
+import moja.refrigerator.aggregate.user.Follow;
+import moja.refrigerator.aggregate.user.User;
+import moja.refrigerator.repository.user.FollowRepository;
+import moja.refrigerator.repository.user.UserRepository;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.context.SecurityContextHolder;
+import org.springframework.security.core.userdetails.UsernameNotFoundException;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+@Service
+public class FollowServiceImpl implements FollowService {
+    private final FollowRepository followRepository;
+    private final UserRepository userRepository;
+
+    public FollowServiceImpl(FollowRepository followRepository, UserRepository userRepository) {
+        this.followRepository = followRepository;
+        this.userRepository = userRepository;
+    }
+
+    @Override
+    @Transactional
+    public void toggleFollow(Long targetUserPk) {
+        // 현재 로그인한 사용자 찾기
+        Authentication authentication = SecurityContextHolder.getContext().getAuthentication();
+        User follower = userRepository.findByUserId(authentication.getName())
+                .orElseThrow(() -> new UsernameNotFoundException("사용자를 찾을 수 없습니다."));
+
+        // 팔로우 대상 사용자 찾기
+        User following = userRepository.findByUserPk(targetUserPk)
+                .orElseThrow(() -> new UsernameNotFoundException("팔로우 하려는 사용자를 찾을 수 없습니다."));
+
+        // 자기 자신 팔로우 방지
+        if (follower.getUserPk() == following.getUserPk()) {
+            throw new IllegalArgumentException("자기 자신을 팔로우할 수 없습니다.");
+        }
+
+        // 이미 팔로우 중이면 언팔로우, 아니면 팔로우
+        if (followRepository.existsByFollowerAndFollowing(follower, following)) {
+            followRepository.deleteByFollowerAndFollowing(follower, following);
+        } else {
+            Follow follow = new Follow();
+            follow.setFollower(follower);
+            follow.setFollowing(following);
+            followRepository.save(follow);
+        }
+    }
+}