[feat/CK-237] 골룸 참여 시 발생하는 동시성 이슈를 해결한다

backend/kirikiri/src/main/java/co/kirikiri/persistence/goalroom/GoalRoomQueryRepository.java

@@ -11,6 +11,8 @@
 
 public interface GoalRoomQueryRepository {
 
+    Optional<GoalRoom> findGoalRoomByIdWithPessimisticLock(Long goalRoomId);
+
     Optional<GoalRoom> findByIdWithRoadmapContent(final Long goalRoomId);
 
     Optional<GoalRoom> findByIdWithContentAndTodos(final Long goalRoomId);

backend/kirikiri/src/main/java/co/kirikiri/persistence/goalroom/GoalRoomQueryRepositoryImpl.java

@@ -15,6 +15,7 @@
 import co.kirikiri.persistence.goalroom.dto.RoadmapGoalRoomsOrderType;
 import com.querydsl.core.types.OrderSpecifier;
 import com.querydsl.core.types.dsl.BooleanExpression;
+import jakarta.persistence.LockModeType;
 import java.time.LocalDate;
 import java.util.List;
 import java.util.Optional;
@@ -27,6 +28,16 @@ public GoalRoomQueryRepositoryImpl() {
         super(GoalRoom.class);
     }
 
+    @Override
+    public Optional<GoalRoom> findGoalRoomByIdWithPessimisticLock(final Long goalRoomId) {
+        return Optional.ofNullable(selectFrom(goalRoom)
+                .innerJoin(goalRoom.goalRoomPendingMembers.values, goalRoomPendingMember)
+                .fetchJoin()
+                .where(goalRoom.id.eq(goalRoomId))
+                .setLockMode(LockModeType.PESSIMISTIC_WRITE)
+                .fetchOne());
+    }
+
     @Override
     public Optional<GoalRoom> findByIdWithRoadmapContent(final Long goalRoomId) {
         return Optional.ofNullable(selectFrom(goalRoom)

backend/kirikiri/src/main/java/co/kirikiri/persistence/goalroom/GoalRoomRepository.java

@@ -1,14 +1,13 @@
 package co.kirikiri.persistence.goalroom;
 
 import co.kirikiri.domain.goalroom.GoalRoom;
-import org.springframework.data.jpa.repository.JpaRepository;
 import java.time.LocalDate;
 import java.util.List;
 import java.util.Optional;
+import org.springframework.data.jpa.repository.JpaRepository;
 
 public interface GoalRoomRepository extends JpaRepository<GoalRoom, Long>, GoalRoomQueryRepository {
-
-    @Override
+
     Optional<GoalRoom> findById(final Long goalRoomId);
 
     List<GoalRoom> findAllByEndDate(final LocalDate endDate);

backend/kirikiri/src/main/java/co/kirikiri/service/goalroom/GoalRoomCreateService.java

@@ -123,7 +123,7 @@ public void join(final String identifier, final Long goalRoomId) {
     }
 
     private GoalRoom findGoalRoomById(final Long goalRoomId) {
-        return goalRoomRepository.findById(goalRoomId)
+        return goalRoomRepository.findGoalRoomByIdWithPessimisticLock(goalRoomId)
                 .orElseThrow(() -> new NotFoundException("존재하지 않는 골룸입니다. goalRoomId = " + goalRoomId));
     }