KKUMI-118 [FEATURE] #73 포스트 좋아요 기능 추가

좋아요 누르는 기능만 추가

src/main/java/com/swmarastro/mykkumiserver/global/exception/ErrorCode.java

@@ -29,6 +29,7 @@ public enum ErrorCode {
     //409 CONFLICT
     DUPLICATE_VALUE(HttpStatus.CONFLICT),
     DUPLICATE_REPORT(HttpStatus.CONFLICT),
+    ALREADY_EXISTS(HttpStatus.CONFLICT),
 
     //500 INTERNAL_SERVER_ERROR
     INTERNAL_SERVER_ERROR(HttpStatus.INTERNAL_SERVER_ERROR),

src/main/java/com/swmarastro/mykkumiserver/like/Likes.java

@@ -0,0 +1,48 @@
+package com.swmarastro.mykkumiserver.like;
+
+import com.swmarastro.mykkumiserver.global.BaseEntity;
+import com.swmarastro.mykkumiserver.post.domain.Post;
+import com.swmarastro.mykkumiserver.user.User;
+import jakarta.persistence.*;
+import lombok.*;
+
+@Entity
+@Builder
+@Getter
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+@AllArgsConstructor(access = AccessLevel.PROTECTED)
+public class Likes extends BaseEntity {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    @Column(name = "likes_id")
+    private Long id;
+
+    private Boolean isDeleted;
+
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "post_id")
+    private Post post;
+
+    @JoinColumn(name = "user_id")
+    @ManyToOne(fetch = FetchType.LAZY)
+    private User user;
+
+    public static Likes of(Post post, User user) {
+        return Likes.builder()
+                .post(post)
+                .user(user)
+                .isDeleted(false)
+                .build();
+    }
+
+    public Boolean like() {
+        isDeleted = false;
+        return true;
+    }
+
+    public Boolean unlike() {
+        isDeleted = true;
+        return true;
+    }
+}

src/main/java/com/swmarastro/mykkumiserver/like/LikesController.java

@@ -0,0 +1,28 @@
+package com.swmarastro.mykkumiserver.like;
+
+import com.swmarastro.mykkumiserver.auth.annotation.Login;
+import com.swmarastro.mykkumiserver.auth.annotation.RequiresLogin;
+import com.swmarastro.mykkumiserver.like.dto.LikesRequest;
+import com.swmarastro.mykkumiserver.like.dto.LikesResponse;
+import com.swmarastro.mykkumiserver.user.User;
+import lombok.RequiredArgsConstructor;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+@RestController
+@RequestMapping("/api/v1")
+@RequiredArgsConstructor
+public class LikesController {
+
+    private final LikesService likeService;
+
+    @RequiresLogin
+    @PostMapping("/likes")
+    public ResponseEntity<LikesResponse> like(@Login User user, @RequestBody LikesRequest request) {
+        LikesResponse response = LikesResponse.of(likeService.like(user, request.getPostId()));
+        return ResponseEntity.ok(response);
+    }
+}

src/main/java/com/swmarastro/mykkumiserver/like/LikesRepository.java

@@ -0,0 +1,14 @@
+package com.swmarastro.mykkumiserver.like;
+
+import com.swmarastro.mykkumiserver.post.domain.Post;
+import com.swmarastro.mykkumiserver.user.User;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
+
+import java.util.Optional;
+
+public interface LikesRepository extends JpaRepository<Likes, Long> {
+
+    @Query("SELECT l from Likes l WHERE l.post = :post AND l.user = :user")
+    Optional<Likes> findByPostAndUser(Post post, User user); //TODO postid, userid로 하는게 나을지???
+}

src/main/java/com/swmarastro/mykkumiserver/like/LikesService.java

@@ -0,0 +1,42 @@
+package com.swmarastro.mykkumiserver.like;
+
+import com.swmarastro.mykkumiserver.global.exception.CommonException;
+import com.swmarastro.mykkumiserver.global.exception.ErrorCode;
+import com.swmarastro.mykkumiserver.post.domain.Post;
+import com.swmarastro.mykkumiserver.post.service.PostService;
+import com.swmarastro.mykkumiserver.user.User;
+import lombok.RequiredArgsConstructor;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import java.util.Optional;
+
+@Service
+@RequiredArgsConstructor
+@Transactional
+public class LikesService {
+
+    private final LikesRepository likeRepository;
+    private final PostService postService;
+
+    public Boolean like(User user, Long postId) {
+
+        Post post = postService.findById(postId);
+
+        //like가 테이블에 있는지 확인
+        Optional<Likes> optionalLike = likeRepository.findByPostAndUser(post, user);
+        //없음 -> 생성하고 좋아요 눌림
+        if (optionalLike.isEmpty()) {
+            Likes like = Likes.of(post, user);
+            likeRepository.save(like);
+            return true;
+        }
+        Likes like = optionalLike.get();
+        //있는데 안눌린 상태 -> 좋아요 눌림
+        if (like.getIsDeleted()) {
+            return like.like();
+        }
+        //있는데 이미 눌린상태 -> 이미 좋아요 누른 포스트입니다.
+        throw new CommonException(ErrorCode.ALREADY_EXISTS, "이미 좋아요를 누른 포스트입니다.", "이미 좋아요를 누른 포스트입니다.");
+    }
+}

src/main/java/com/swmarastro/mykkumiserver/like/dto/LikesRequest.java

@@ -0,0 +1,9 @@
+package com.swmarastro.mykkumiserver.like.dto;
+
+import lombok.Getter;
+
+@Getter
+public class LikesRequest {
+
+    private Long postId;
+}

src/main/java/com/swmarastro/mykkumiserver/like/dto/LikesResponse.java

@@ -0,0 +1,17 @@
+package com.swmarastro.mykkumiserver.like.dto;
+
+import lombok.Builder;
+import lombok.Getter;
+
+@Getter
+@Builder
+public class LikesResponse {
+
+    private Boolean success;
+
+    public static LikesResponse of(Boolean success) {
+        return LikesResponse.builder()
+                .success(success)
+                .build();
+    }
+}

src/main/java/com/swmarastro/mykkumiserver/post/service/PostService.java

@@ -180,4 +180,9 @@ private void saveHashtags(List<String> contentTexts, Post savedPost) {
                 })
                 .forEach(hashtagService::savePostHashtag); // PostHashtag 저장
     }
+
+    public Post findById(Long postId) {
+        return postRepository.findById(postId)
+                .orElseThrow(() -> new CommonException(ErrorCode.NOT_FOUND, "포스트가 존재하지 않습니다.", "포스트가 존재하지 않습니다."));
+    }
 }