[Feat] 코스 좋아요 토글 API 추가

src/main/java/com/semosan/api/common/status/SuccessStatus.java

@@ -43,6 +43,7 @@ public enum SuccessStatus implements BaseStatus {
     MOUNTAIN_MAP_SUCCESS(HttpStatus.OK, "MTN_200_7", "지도 영역 내 산 조회에 성공했습니다."),
     MOUNTAIN_RECOMMENDATION_SUCCESS(HttpStatus.OK, "MTN_200_8", "레벨 맞춤 산 추천 조회에 성공했습니다."),
     COURSE_DETAIL_SUCCESS(HttpStatus.OK, "MTN_200_9", "코스 상세 정보 조회에 성공했습니다."),
+    COURSE_LIKE_TOGGLE_SUCCESS(HttpStatus.OK, "MTN_200_10", "코스 좋아요 처리에 성공했습니다."),
 
     /**
      * Hiking Record

src/main/java/com/semosan/api/domain/mountain/controller/CourseController.java

@@ -4,12 +4,15 @@
 import com.semosan.api.common.status.SuccessStatus;
 import com.semosan.api.domain.mountain.controller.docs.CourseControllerDocs;
 import com.semosan.api.domain.mountain.dto.response.CourseDetailResponse;
+import com.semosan.api.domain.mountain.dto.response.CourseLikeToggleResponse;
+import com.semosan.api.domain.mountain.service.CourseLikeService;
 import com.semosan.api.domain.mountain.service.CourseService;
 import lombok.RequiredArgsConstructor;
 import org.springframework.http.ResponseEntity;
 import org.springframework.security.core.annotation.AuthenticationPrincipal;
 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;
 
@@ -19,14 +22,27 @@
 public class CourseController implements CourseControllerDocs {
 
     private final CourseService courseService;
+    private final CourseLikeService courseLikeService;
 
     @GetMapping("/{courseId}")
     @Override
     public ResponseEntity<ApiResponse<CourseDetailResponse>> getCourseDetail(
             @AuthenticationPrincipal Long userId,
             @PathVariable Long courseId
     ) {
-        CourseDetailResponse response = courseService.getCourseDetail(courseId);
+        CourseDetailResponse response = courseService.getCourseDetail(userId, courseId);
         return ApiResponse.success(SuccessStatus.COURSE_DETAIL_SUCCESS, response);
     }
+
+    @PostMapping("/{courseId}/like")
+    @Override
+    public ResponseEntity<ApiResponse<CourseLikeToggleResponse>> toggleCourseLike(
+            @AuthenticationPrincipal Long userId,
+            @PathVariable Long courseId
+    ) {
+        return ApiResponse.success(
+                SuccessStatus.COURSE_LIKE_TOGGLE_SUCCESS,
+                courseLikeService.toggleCourseLike(userId, courseId)
+        );
+    }
 }

src/main/java/com/semosan/api/domain/mountain/controller/docs/CourseControllerDocs.java

@@ -2,6 +2,7 @@
 
 import com.semosan.api.common.response.ApiResponse;
 import com.semosan.api.domain.mountain.dto.response.CourseDetailResponse;
+import com.semosan.api.domain.mountain.dto.response.CourseLikeToggleResponse;
 import io.swagger.v3.oas.annotations.Operation;
 import io.swagger.v3.oas.annotations.Parameter;
 import io.swagger.v3.oas.annotations.media.Content;
@@ -36,4 +37,25 @@ ResponseEntity<ApiResponse<CourseDetailResponse>> getCourseDetail(
             @Parameter(description = "코스 ID", required = true)
             @PathVariable Long courseId
     );
+
+    @Operation(
+            summary = "코스 좋아요 토글",
+            description = "로그인한 사용자가 코스 좋아요를 누르거나 취소합니다."
+    )
+    @ApiResponses({
+            @io.swagger.v3.oas.annotations.responses.ApiResponse(
+                    responseCode = "200",
+                    description = "코스 좋아요 토글 성공"
+            ),
+            @io.swagger.v3.oas.annotations.responses.ApiResponse(
+                    responseCode = "404",
+                    description = "코스를 찾을 수 없음 (MTN_404_3)",
+                    content = @Content(schema = @Schema(implementation = ApiResponse.class))
+            )
+    })
+    ResponseEntity<ApiResponse<CourseLikeToggleResponse>> toggleCourseLike(
+            @AuthenticationPrincipal Long userId,
+            @Parameter(description = "코스 ID", required = true)
+            @PathVariable Long courseId
+    );
 }

src/main/java/com/semosan/api/domain/mountain/dto/response/CourseDetailResponse.java

@@ -12,6 +12,7 @@
  */
 public record CourseDetailResponse(
         Long id,
+        Long mountainId,
         String name,
         Difficulty difficulty,
         Double distance,
@@ -21,12 +22,14 @@ public record CourseDetailResponse(
         Double ascent,
         Double descent,
         Double maxAltitude,
+        boolean likedByMe,
         @JsonRawValue String polyline,
         @JsonRawValue String altitudes
 ) {
-    public static CourseDetailResponse from(CourseDetailProjection p) {
+    public static CourseDetailResponse from(CourseDetailProjection p, boolean likedByMe) {
         return new CourseDetailResponse(
                 p.getId(),
+                p.getMountainId(),
                 p.getName(),
                 p.getDifficulty() == null ? null : Difficulty.valueOf(p.getDifficulty()),
                 p.getDistance(),
@@ -36,6 +39,7 @@ public static CourseDetailResponse from(CourseDetailProjection p) {
                 p.getAscent(),
                 p.getDescent(),
                 p.getMaxAltitude(),
+                likedByMe,
                 p.getPolyline(),
                 p.getAltitudes()
         );

src/main/java/com/semosan/api/domain/mountain/dto/response/CourseLikeToggleResponse.java

@@ -0,0 +1,6 @@
+package com.semosan.api.domain.mountain.dto.response;
+
+public record CourseLikeToggleResponse(
+        boolean liked
+) {
+}

src/main/java/com/semosan/api/domain/mountain/entity/CourseLike.java

@@ -0,0 +1,58 @@
+package com.semosan.api.domain.mountain.entity;
+
+import com.semosan.api.common.base.BaseEntity;
+import com.semosan.api.domain.user.entity.User;
+import jakarta.persistence.Entity;
+import jakarta.persistence.FetchType;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.GenerationType;
+import jakarta.persistence.Id;
+import jakarta.persistence.Index;
+import jakarta.persistence.JoinColumn;
+import jakarta.persistence.ManyToOne;
+import jakarta.persistence.Table;
+import jakarta.persistence.UniqueConstraint;
+import lombok.AccessLevel;
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+
+@Table(
+        name = "course_likes",
+        uniqueConstraints = {
+                @UniqueConstraint(
+                        name = "uk_course_likes_user_id_course_id",
+                        columnNames = {"user_id", "course_id"}
+                )
+        },
+        indexes = {
+                @Index(name = "idx_course_likes_user_id_created_at", columnList = "user_id, created_at DESC")
+        }
+)
+@Getter
+@Entity
+@Builder(access = AccessLevel.PROTECTED)
+@AllArgsConstructor(access = AccessLevel.PROTECTED)
+@NoArgsConstructor(access = AccessLevel.PROTECTED)
+public class CourseLike extends BaseEntity {
+
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private Long id;
+
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "user_id", nullable = false)
+    private User user;
+
+    @ManyToOne(fetch = FetchType.LAZY)
+    @JoinColumn(name = "course_id", nullable = false)
+    private Course course;
+
+    public static CourseLike create(User user, Course course) {
+        return CourseLike.builder()
+                .user(user)
+                .course(course)
+                .build();
+    }
+}

src/main/java/com/semosan/api/domain/mountain/repository/CourseLikeRepository.java

@@ -0,0 +1,20 @@
+package com.semosan.api.domain.mountain.repository;
+
+import com.semosan.api.domain.mountain.entity.CourseLike;
+import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Modifying;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
+
+import java.util.Optional;
+
+public interface CourseLikeRepository extends JpaRepository<CourseLike, Long> {
+
+    boolean existsByUser_IdAndCourse_Id(Long userId, Long courseId);
+
+    Optional<CourseLike> findByUser_IdAndCourse_Id(Long userId, Long courseId);
+
+    @Modifying(clearAutomatically = true)
+    @Query("DELETE FROM CourseLike cl WHERE cl.user.id = :userId")
+    void deleteByUser_Id(@Param("userId") Long userId);
+}

src/main/java/com/semosan/api/domain/mountain/repository/CourseRepository.java

@@ -29,6 +29,7 @@ public interface CourseRepository extends JpaRepository<Course, Long> {
             value = """
                     SELECT
                         c.id            AS id,
+                        c.mountain_id   AS mountainId,
                         c.name          AS name,
                         c.difficulty    AS difficulty,
                         c.distance      AS distance,

src/main/java/com/semosan/api/domain/mountain/repository/projection/CourseDetailProjection.java

@@ -7,6 +7,7 @@
  */
 public interface CourseDetailProjection {
     Long getId();
+    Long getMountainId();
     String getName();
     String getDifficulty();
     Double getDistance();

src/main/java/com/semosan/api/domain/mountain/service/CourseLikeService.java

@@ -0,0 +1,59 @@
+package com.semosan.api.domain.mountain.service;
+
+import com.semosan.api.common.exception.GeneralException;
+import com.semosan.api.common.status.ErrorStatus;
+import com.semosan.api.domain.mountain.dto.response.CourseLikeToggleResponse;
+import com.semosan.api.domain.mountain.entity.Course;
+import com.semosan.api.domain.mountain.entity.CourseLike;
+import com.semosan.api.domain.mountain.repository.CourseLikeRepository;
+import com.semosan.api.domain.mountain.repository.CourseRepository;
+import com.semosan.api.domain.user.entity.User;
+import com.semosan.api.domain.user.service.UserReader;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.dao.DataIntegrityViolationException;
+import org.springframework.stereotype.Service;
+import org.springframework.transaction.annotation.Transactional;
+
+@Slf4j
+@Service
+@RequiredArgsConstructor
+public class CourseLikeService {
+
+    private final CourseLikeRepository courseLikeRepository;
+    private final CourseRepository courseRepository;
+    private final UserReader userReader;
+
+    @Transactional(noRollbackFor = DataIntegrityViolationException.class)
+    public CourseLikeToggleResponse toggleCourseLike(Long userId, Long courseId) {
+        boolean liked = toggle(userId, courseId);
+        return new CourseLikeToggleResponse(liked);
+    }
+
+    private boolean toggle(Long userId, Long courseId) {
+        User user = userReader.findCompletedOnboardingUserById(userId);
+        Course course = findCourseById(courseId);
+
+        return courseLikeRepository.findByUser_IdAndCourse_Id(userId, courseId)
+                .map(existing -> {
+                    courseLikeRepository.delete(existing);
+                    return false;
+                })
+                .orElseGet(() -> createCourseLike(user, course, userId, courseId));
+    }
+
+    private boolean createCourseLike(User user, Course course, Long userId, Long courseId) {
+        try {
+            courseLikeRepository.save(CourseLike.create(user, course));
+            return true;
+        } catch (DataIntegrityViolationException e) {
+            log.warn("CourseLike 동시 요청 감지: courseId={}, userId={}", courseId, userId);
+            return true;
+        }
+    }
+
+    private Course findCourseById(Long courseId) {
+        return courseRepository.findById(courseId)
+                .orElseThrow(() -> new GeneralException(ErrorStatus.COURSE_NOT_FOUND));
+    }
+}

src/main/java/com/semosan/api/domain/mountain/service/CourseService.java

@@ -3,7 +3,9 @@
 import com.semosan.api.common.exception.GeneralException;
 import com.semosan.api.common.status.ErrorStatus;
 import com.semosan.api.domain.mountain.dto.response.CourseDetailResponse;
+import com.semosan.api.domain.mountain.repository.CourseLikeRepository;
 import com.semosan.api.domain.mountain.repository.CourseRepository;
+import com.semosan.api.domain.mountain.repository.projection.CourseDetailProjection;
 import lombok.RequiredArgsConstructor;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
@@ -14,10 +16,12 @@
 public class CourseService {
 
     private final CourseRepository courseRepository;
+    private final CourseLikeRepository courseLikeRepository;
 
-    public CourseDetailResponse getCourseDetail(Long courseId) {
-        return courseRepository.findCourseDetailById(courseId)
-                .map(CourseDetailResponse::from)
+    public CourseDetailResponse getCourseDetail(Long userId, Long courseId) {
+        CourseDetailProjection course = courseRepository.findCourseDetailById(courseId)
                 .orElseThrow(() -> new GeneralException(ErrorStatus.COURSE_NOT_FOUND));
+        boolean likedByMe = userId != null && courseLikeRepository.existsByUser_IdAndCourse_Id(userId, courseId);
+        return CourseDetailResponse.from(course, likedByMe);
     }
 }

src/main/java/com/semosan/api/domain/user/service/UserService.java

@@ -4,6 +4,7 @@
 import com.semosan.api.common.status.ErrorStatus;
 import com.semosan.api.domain.hiking.repository.HikingMemberRepository;
 import com.semosan.api.domain.hiking.repository.HikingRecordRepository;
+import com.semosan.api.domain.mountain.repository.CourseLikeRepository;
 import com.semosan.api.domain.mountain.repository.MountainLikeRepository;
 import com.semosan.api.domain.notification.repository.NotificationRepository;
 import com.semosan.api.domain.review.repository.ReviewRepository;
@@ -33,6 +34,7 @@ public class UserService {
     private final UserNotificationSettingRepository userNotificationSettingRepository;
     private final UserOnboardingRepository userOnboardingRepository;
     private final MountainLikeRepository mountainLikeRepository;
+    private final CourseLikeRepository courseLikeRepository;
     private final ReviewRepository reviewRepository;
     private final HikingMemberRepository hikingMemberRepository;
     private final HikingRecordRepository hikingRecordRepository;
@@ -143,6 +145,7 @@ public void withdrawUser(User user) {
 
     private void deleteUserChildRecords(Long userId) {
         mountainLikeRepository.deleteByUser_Id(userId);
+        courseLikeRepository.deleteByUser_Id(userId);
         reviewRepository.deleteByUser_Id(userId);
         List<Long> recordIdsToDelete = hikingRecordRepository.findRecordIdsOnlyParticipatedByUser(userId);
         hikingMemberRepository.deleteByUser_Id(userId);

src/main/resources/db/migration/V26__create_course_likes.sql

@@ -0,0 +1,18 @@
+CREATE TABLE IF NOT EXISTS course_likes
+(
+    id         bigint generated by default as identity
+        primary key,
+    created_at timestamp(6) not null,
+    updated_at timestamp(6) not null,
+    user_id    bigint       not null
+        constraint fk_course_likes_user
+            references users,
+    course_id  bigint       not null
+        constraint fk_course_likes_course
+            references courses,
+    constraint uk_course_likes_user_id_course_id
+        unique (user_id, course_id)
+);
+
+CREATE INDEX IF NOT EXISTS idx_course_likes_user_id_created_at
+    on course_likes (user_id asc, created_at desc);