Feature: 좋아요 기능

src/main/java/com/develop_mouse/gummy_dang/common/domain/ResponseCode.java

@@ -24,6 +24,8 @@ public enum ResponseCode {
 	IMAGE_NOT_FOUND("IMG-001", "There's no image onb request."),
 	COMMENT_NOT_FOUND("CMT-001", "No such comment exist."),
 	COMMENT_WRITER_DIFFERENCE("CMT-002", "User and author are different"),
+	LIKE_NOT_FOUND("LKE-001", "Like count not found."),
+	LIKE_DUPLICATE("LKE-002", "Like is duplicate.")
 	;
 
 	private final String responseCode;

src/main/java/com/develop_mouse/gummy_dang/like/controller/LikeControllerV2.java

@@ -0,0 +1,51 @@
+package com.develop_mouse.gummy_dang.like.controller;
+
+import org.springframework.web.bind.annotation.DeleteMapping;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+
+import com.develop_mouse.gummy_dang.common.domain.response.Response;
+import com.develop_mouse.gummy_dang.like.domain.LikeCount;
+import com.develop_mouse.gummy_dang.like.domain.LikeResponse;
+import com.develop_mouse.gummy_dang.like.service.LikeServiceV2;
+
+import lombok.RequiredArgsConstructor;
+
+@RestController
+@RequestMapping("/api")
+@RequiredArgsConstructor
+public class LikeControllerV2 {
+
+	private final LikeServiceV2 likeService;
+
+	/**
+	 * 좋아요 누르기
+	 * @param postId : 누르고자 하는 게시글 id
+	 */
+	@PostMapping("/post/{postId}/like")
+	public Response<LikeResponse> createLike(@PathVariable Long postId) {
+		return likeService.createLike(postId);
+	}
+
+	/**
+	 * 좋아요 취소
+	 * @param postId : 취소하고자 하는 게시글 id
+	 */
+	@DeleteMapping("/post/{postId}/like")
+	public Response<Void> deleteLike(@PathVariable Long postId) {
+		return likeService.deleteLike(postId);
+	}
+
+	/**
+	 * 게시글의 총 좋아요 수 가져오기
+	 * @param postId : 조회하고자 하는 게시글 id
+	 */
+	@GetMapping("/post/{postId}/like-count")
+	public Response<LikeCount> getLikeCount(@PathVariable Long postId) {
+		return likeService.getLikeCount(postId);
+	}
+
+}

src/main/java/com/develop_mouse/gummy_dang/like/domain/LikeCount.java

@@ -0,0 +1,14 @@
+package com.develop_mouse.gummy_dang.like.domain;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Getter
+@AllArgsConstructor
+@NoArgsConstructor
+public class LikeCount {
+
+	private Integer likeCount;
+
+}

src/main/java/com/develop_mouse/gummy_dang/like/domain/LikeResponse.java

@@ -0,0 +1,15 @@
+package com.develop_mouse.gummy_dang.like.domain;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Getter
+@AllArgsConstructor
+@NoArgsConstructor
+public class LikeResponse {
+
+	private Long likeId;
+	private Long postId;
+
+}

src/main/java/com/develop_mouse/gummy_dang/like/repository/LikeRepository.java

@@ -0,0 +1,14 @@
+package com.develop_mouse.gummy_dang.like.repository;
+
+import java.util.Optional;
+
+import org.springframework.data.jpa.repository.JpaRepository;
+
+import com.develop_mouse.gummy_dang.like.domain.entity.Like;
+import com.develop_mouse.gummy_dang.member.domain.entity.Member;
+import com.develop_mouse.gummy_dang.post.domain.entity.Post;
+
+public interface LikeRepository extends JpaRepository<Like, Long> {
+
+	Optional<Like> findByMemberAndPost(Member member, Post post);
+}

src/main/java/com/develop_mouse/gummy_dang/like/service/LikeServiceV2.java

@@ -0,0 +1,90 @@
+package com.develop_mouse.gummy_dang.like.service;
+
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+import com.develop_mouse.gummy_dang.authentication.util.SecurityContextUtil;
+import com.develop_mouse.gummy_dang.common.Exception.BusinessException;
+import com.develop_mouse.gummy_dang.common.domain.ResponseCode;
+import com.develop_mouse.gummy_dang.common.domain.response.Response;
+import com.develop_mouse.gummy_dang.like.domain.LikeCount;
+import com.develop_mouse.gummy_dang.like.domain.LikeResponse;
+import com.develop_mouse.gummy_dang.like.domain.entity.Like;
+import com.develop_mouse.gummy_dang.like.repository.LikeRepository;
+import com.develop_mouse.gummy_dang.member.domain.entity.Member;
+import com.develop_mouse.gummy_dang.member.repository.MemberRepository;
+import com.develop_mouse.gummy_dang.post.domain.entity.Post;
+import com.develop_mouse.gummy_dang.post.repository.PostRepository;
+
+import lombok.RequiredArgsConstructor;
+
+@Service
+@Transactional
+@RequiredArgsConstructor
+public class LikeServiceV2 {
+
+	private final LikeRepository likeRepository;
+	private final PostRepository postRepository;
+	private final SecurityContextUtil securityContextUtil;
+	private final MemberRepository memberRepository;
+
+	public Response<LikeResponse> createLike(Long postId) {
+		// Member 정보 조회
+		Member member = memberRepository.findById(securityContextUtil.getContextMemberInfo().getMemberId())
+			.stream()
+			.findAny()
+			.orElseThrow(() -> new BusinessException(ResponseCode.MEMBER_NOT_FOUND));
+
+		// Post 정보 조회
+		Post post = postRepository.findById(postId).stream()
+			.findAny()
+			.orElseThrow(() -> new BusinessException(ResponseCode.POST_NOT_FOUND));
+
+		likeRepository.findByMemberAndPost(member, post).ifPresent(like -> {
+			throw new BusinessException(ResponseCode.LIKE_DUPLICATE);
+		});
+
+		Like like = Like.builder()
+			.member(member)
+			.post(post)
+			.build();
+
+		Like savedLike = likeRepository.save(like);
+
+		return Response.ok(new LikeResponse(savedLike.getId(), post.getId()));
+	}
+
+	public Response<Void> deleteLike(Long postId) {
+		// Member 정보 조회
+		Member member = memberRepository.findById(securityContextUtil.getContextMemberInfo().getMemberId())
+			.stream()
+			.findAny()
+			.orElseThrow(() -> new BusinessException(ResponseCode.MEMBER_NOT_FOUND));
+
+		// Post 정보 조회
+		Post post = postRepository.findById(postId).stream()
+			.findAny()
+			.orElseThrow(() -> new BusinessException(ResponseCode.POST_NOT_FOUND));
+
+		Like like = likeRepository.findByMemberAndPost(member, post).stream()
+			.findAny()
+			.orElseThrow(() -> new BusinessException(ResponseCode.LIKE_NOT_FOUND));
+
+		if (like.getMember() != member) {
+			throw new BusinessException(ResponseCode.MEMBER_UNAUTHORIZED);
+		}
+
+		likeRepository.delete(like);
+
+		return Response.ok();
+	}
+
+	public Response<LikeCount> getLikeCount(Long postId) {
+		Post post = postRepository.findByIdIs(postId).stream()
+			.findAny()
+			.orElseThrow(() -> new BusinessException(ResponseCode.POST_NOT_FOUND));
+
+		return Response.ok(new LikeCount(post.getLike().size()));
+	}
+
+}

src/main/java/com/develop_mouse/gummy_dang/post/domain/response/PostResponse.java

@@ -23,6 +23,8 @@ public class PostResponse {
 	private String description;
 	private String imageUrl;
 	private LocalDate createdAt;
+	@Builder.Default
+	private Boolean liked = false;
 
 	private List<PostCoordinateDTO> postCoordinates;
 

src/main/java/com/develop_mouse/gummy_dang/post/repository/PostRepository.java

@@ -1,10 +1,20 @@
 package com.develop_mouse.gummy_dang.post.repository;
 
+import java.util.List;
+import java.util.Optional;
+
 import com.develop_mouse.gummy_dang.post.domain.entity.Post;
+
+import org.springframework.data.jpa.repository.EntityGraph;
 import org.springframework.data.jpa.repository.JpaRepository;
 
 
 public interface PostRepository extends JpaRepository<Post, Long>{
 
+	@EntityGraph(attributePaths = {"like"})
+	Optional<Post> findByIdIs(Long postId);
+
+	@EntityGraph(attributePaths = {"member"})
+	List<Post> findAll();
 }
 

src/main/java/com/develop_mouse/gummy_dang/post/service/PostServiceImpl.java

@@ -4,10 +4,10 @@
 import com.develop_mouse.gummy_dang.common.Exception.BusinessException;
 import com.develop_mouse.gummy_dang.common.domain.ResponseCode;
 import com.develop_mouse.gummy_dang.common.domain.response.Response;
+import com.develop_mouse.gummy_dang.like.repository.LikeRepository;
 import com.develop_mouse.gummy_dang.member.domain.entity.Member;
 import com.develop_mouse.gummy_dang.member.repository.MemberRepository;
 import com.develop_mouse.gummy_dang.post.DTO.PostCoordinateDTO;
-import com.develop_mouse.gummy_dang.post.DTO.PostDTO;
 import com.develop_mouse.gummy_dang.post.domain.entity.Post;
 import com.develop_mouse.gummy_dang.post.domain.entity.PostCoordinate;
 import com.develop_mouse.gummy_dang.post.domain.request.PostRequest;
@@ -43,6 +43,7 @@ public class PostServiceImpl implements PostService{
     private final MemberRepository memberRepository;
     private final SecurityContextUtil securityContextUtil; // 현 사용자 불러오기 위해 주입
     private final PostCoordinateRepository postCoordinateRepository;
+    private final LikeRepository likeRepository;
 
     // +) 이미지에서 사용
     private ServletContext servletContext; // ServletContext 주입
@@ -189,6 +190,7 @@ public Response<Void> deletePost(Long id) {
     // 글 하나 보기
     @Override
     public Response<PostResponse> detailPost(Long id) {
+        Optional<Member> member = memberRepository.findById(securityContextUtil.getContextMemberInfo().getMemberId());
         Post post = postRepository.findById(id).stream()
             .findAny()
             .orElseThrow(() -> new BusinessException(ResponseCode.POST_NOT_FOUND));
@@ -198,6 +200,7 @@ public Response<PostResponse> detailPost(Long id) {
             .title(post.getTitle())
             .description(post.getDescription())
             .imageUrl(post.getImageUrl())
+            .liked(member.isPresent() && likeRepository.findByMemberAndPost(member.get(), post).isPresent())
             .postCoordinates(post.getPostCoordinates().stream()
                 .map(PostCoordinateDTO::fromEntity)
                 .toList())
@@ -210,6 +213,7 @@ public Response<PostResponse> detailPost(Long id) {
     // 글 목록
     @Override
     public Response<List<PostResponse>> postList() {
+        Optional<Member> member = memberRepository.findById(securityContextUtil.getContextMemberInfo().getMemberId());
         List<Post> posts = postRepository.findAll();
 
         List<PostResponse> postResponses = posts.stream()
@@ -218,9 +222,11 @@ public Response<List<PostResponse>> postList() {
                 .title(post.getTitle())
                 .description(post.getDescription())
                 .imageUrl(post.getImageUrl())
+                .liked(member.isPresent() && likeRepository.findByMemberAndPost(member.get(), post).isPresent())
                 .postCoordinates(post.getPostCoordinates().stream()
                     .map(PostCoordinateDTO::fromEntity)
                     .toList())
+                .createdAt(post.getCreatedAt().toLocalDate())
                 .build())
             .toList();