reduce fetched data

ls1intum · Oct 29, 2023 · d70079a · d70079a
1 parent 7cb5f1c
commit d70079a
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Showing 2 changed files with 19 additions and 19 deletions.
diff --git a/src/main/java/de/tum/in/www1/artemis/repository/CompetencyRepository.java b/src/main/java/de/tum/in/www1/artemis/repository/CompetencyRepository.java
@@ -1,11 +1,14 @@
 package de.tum.in.www1.artemis.repository;
 
+import static org.springframework.data.jpa.repository.EntityGraph.EntityGraphType.LOAD;
+
 import java.util.Optional;
 import java.util.Set;
 
 import org.springframework.cache.annotation.Cacheable;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.Pageable;
+import org.springframework.data.jpa.repository.EntityGraph;
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.data.jpa.repository.Query;
 import org.springframework.data.repository.query.Param;
@@ -47,17 +50,19 @@ public interface CompetencyRepository extends JpaRepository<Competency, Long> {
     Optional<Competency> findByIdWithLectureUnits(@Param("competencyId") long competencyId);
 
     @Query("""
-            SELECT c
-            FROM Competency c
-                LEFT JOIN FETCH c.userProgress
-                LEFT JOIN FETCH c.exercises
-                LEFT JOIN FETCH c.lectureUnits lu
-                LEFT JOIN FETCH lu.completedUsers
-                LEFT JOIN FETCH lu.lecture
-                LEFT JOIN FETCH lu.exercise
-            WHERE c.id = :competencyId
+            SELECT competency
+            FROM Competency competency
+                LEFT JOIN competency.userProgress progress
+                    ON competency.id = progress.learningGoal.id AND progress.user.id = :userId
+                LEFT JOIN FETCH competency.exercises
+                LEFT JOIN FETCH competency.lectureUnits lectureUnits
+                LEFT JOIN lectureUnits.completedUsers completedUsers
+                    ON lectureUnits.id = completedUsers.lectureUnit.id AND completedUsers.user.id = :userId
+                LEFT JOIN FETCH lectureUnits.lecture
+            WHERE competency.id = :competencyId
             """)
-    Optional<Competency> findByIdWithExercisesAndLectureUnits(@Param("competencyId") Long competencyId);
+    @EntityGraph(type = LOAD, attributePaths = { "userProgress", "lectureUnits.completedUsers" })
+    Optional<Competency> findByIdWithExercisesAndLectureUnitsAndProgressForUser(@Param("competencyId") long competencyId, @Param("userId") long userId);
 
     @Query("""
             SELECT c
@@ -162,8 +167,8 @@ default Competency findByIdWithLectureUnitsElseThrow(Long competencyId) {
         return findByIdWithLectureUnits(competencyId).orElseThrow(() -> new EntityNotFoundException("Competency", competencyId));
     }
 
-    default Competency findByIdWithExercisesAndLectureUnitsElseThrow(Long competencyId) {
-        return findByIdWithExercisesAndLectureUnits(competencyId).orElseThrow(() -> new EntityNotFoundException("Competency", competencyId));
+    default Competency findByIdWithExercisesAndLectureUnitsAndProgressForUserElseThrow(long competencyId, long userId) {
+        return findByIdWithExercisesAndLectureUnitsAndProgressForUser(competencyId, userId).orElseThrow(() -> new EntityNotFoundException("Competency", competencyId));
     }
 
     long countByCourse(Course course);

diff --git a/src/main/java/de/tum/in/www1/artemis/web/rest/CompetencyResource.java b/src/main/java/de/tum/in/www1/artemis/web/rest/CompetencyResource.java
@@ -146,15 +146,10 @@ public ResponseEntity<Competency> getCompetency(@PathVariable Long competencyId,
         long start = System.nanoTime();
         var currentUser = userRepository.getUserWithGroupsAndAuthorities();
         var course = courseRepository.findByIdElseThrow(courseId);
-        // TODO: this database request is quite intense and might lead to memory issues
-        // it loads many completed user objects even if those are not necessary which could include are large object graph
-        var competency = competencyRepository.findByIdWithExercisesAndLectureUnitsElseThrow(competencyId);
+        var competency = competencyRepository.findByIdWithExercisesAndLectureUnitsAndProgressForUserElseThrow(competencyId, currentUser.getId());
         checkAuthorizationForCompetency(Role.STUDENT, course, competency);
 
-        competency.setUserProgress(competencyProgressRepository.findByCompetencyIdAndUserId(competencyId, currentUser.getId()).map(Set::of).orElse(Set.of()));
-        // Set completion status and remove exercise units (redundant as we also return all exercises)
-        competency.setLectureUnits(competency.getLectureUnits().stream().filter(lectureUnit -> !(lectureUnit instanceof ExerciseUnit))
-                .filter(lectureUnit -> authorizationCheckService.isAllowedToSeeLectureUnit(lectureUnit, currentUser))
+        competency.setLectureUnits(competency.getLectureUnits().stream().filter(lectureUnit -> authorizationCheckService.isAllowedToSeeLectureUnit(lectureUnit, currentUser))
                 .peek(lectureUnit -> lectureUnit.setCompleted(lectureUnit.isCompletedFor(currentUser))).collect(Collectors.toSet()));
         competency.setExercises(
                 competency.getExercises().stream().filter(exercise -> authorizationCheckService.isAllowedToSeeExercise(exercise, currentUser)).collect(Collectors.toSet()));