[BE] 북마크 알림 리팩토링 (JOIN FETCH 사용한 N+1 문제 해결)

Jinwook94 · Nov 22, 2023 · e02141f · e02141f
1 parent 0c60d14
commit e02141f
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Showing 2 changed files with 11 additions and 2 deletions.
diff --git a/backend/src/main/java/com/bootme/bookmark/repository/CourseBookmarkRepository.java b/backend/src/main/java/com/bootme/bookmark/repository/CourseBookmarkRepository.java
@@ -2,7 +2,9 @@
 
 import com.bootme.bookmark.domain.CourseBookmark;
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
 
+import java.time.LocalDate;
 import java.util.List;
 import java.util.Optional;
 
@@ -14,4 +16,12 @@ public interface CourseBookmarkRepository extends JpaRepository<CourseBookmark,
 
     List<CourseBookmark> findByBookmark_Id(Long bookmarkId);
 
+    @Query("SELECT cb FROM CourseBookmark cb " +
+            "JOIN FETCH cb.course c " +
+            "JOIN FETCH cb.bookmark b " +
+            "JOIN FETCH b.member m " +
+            "WHERE c.dates.registrationStartDate <= :date " +
+            "AND c.dates.registrationEndDate >= :date")
+    List<CourseBookmark> findAllWithCourseAndMemberOnDate(LocalDate date);
+
 }
diff --git a/backend/src/main/java/com/bootme/course/scheduler/CourseScheduler.java b/backend/src/main/java/com/bootme/course/scheduler/CourseScheduler.java
@@ -67,10 +67,9 @@ public void notifyCourseRegistrationEnd() {
     // todo: N+1 문제 → JOIN FETCH 사용한 해결 필요
     @Transactional
     public void notifyBookmarkCourses(NotificationEventType event, LocalDate date) {
-        List<CourseBookmark> courseBookmarks = courseBookmarkRepository.findAll();
+        List<CourseBookmark> courseBookmarks = courseBookmarkRepository.findAllWithCourseAndMemberOnDate(date);
 
         List<Notification> notifications = courseBookmarks.stream()
-                .filter(cb -> cb.getCourse().isEventOnDate(event, date))
                 .map(cb -> notificationFactory.createCourseBookmarkNotification(cb.getBookmark().getMember(), event, cb))
                 .toList();