diff --git a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/AuthorizationTest.java b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/AuthorizationTest.java
index 3380c35..4b495d2 100644
--- a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/AuthorizationTest.java
+++ b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/AuthorizationTest.java
@@ -12,12 +12,14 @@
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.graphql.ResponseError;
-import org.springframework.graphql.test.tester.HttpGraphQlTester;
+import org.springframework.graphql.test.tester.WebGraphQlTester;
 import org.springframework.test.context.ContextConfiguration;
 import org.springframework.transaction.annotation.Transactional;
 
 import java.time.OffsetDateTime;
-import java.util.*;
+import java.util.Collections;
+import java.util.List;
+import java.util.UUID;
 
 import static de.unistuttgart.iste.meitrex.common.testutil.TestUsers.userWithMembershipInCourseWithId;
 import static de.unistuttgart.iste.meitrex.common.user_handling.LoggedInUser.UserRoleInCourse.STUDENT;
@@ -196,7 +198,7 @@ void testUpdateChapterAdminOnly(final HttpGraphQlTester tester) {
     }
 
     @Test
-    void testDeleteChapterAdminOnly(HttpGraphQlTester tester) {
+    void testDeleteChapterAdminOnly(WebGraphQlTester tester) {
         final ChapterEntity chapterEntity = chapterRepository.save(TestUtils.dummyChapterBuilder().courseId(courseId).build());
 
         final String query = """
diff --git a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationCourseMembershipTest.java b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationCourseMembershipTest.java
index af56ed4..0ba413d 100644
--- a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationCourseMembershipTest.java
+++ b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationCourseMembershipTest.java
@@ -11,7 +11,7 @@
 import de.unistuttgart.iste.meitrex.generated.dto.UserRoleInCourse;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.graphql.test.tester.HttpGraphQlTester;
+import org.springframework.graphql.test.tester.WebGraphQlTester;
 
 import java.util.UUID;
 
@@ -28,7 +28,7 @@ class MutationCourseMembershipTest {
     private CourseRepository courseRepository;
 
     @Test
-    void createMembershipTest(HttpGraphQlTester tester) {
+    void createMembershipTest(WebGraphQlTester tester) {
         // create course
         final CourseEntity course = courseRepository.save(TestUtils.dummyCourseBuilder().build());
 
@@ -71,7 +71,7 @@ void createMembershipTest(HttpGraphQlTester tester) {
     }
 
     @Test
-    void updateMembershipMembershipNotExistingTest(HttpGraphQlTester tester) {
+    void updateMembershipMembershipNotExistingTest(WebGraphQlTester tester) {
         final UUID courseId = UUID.randomUUID();
 
         // create admin user object
@@ -118,7 +118,7 @@ void updateMembershipMembershipNotExistingTest(HttpGraphQlTester tester) {
     }
 
     @Test
-    void updateMembershipTest(HttpGraphQlTester tester) {
+    void updateMembershipTest(WebGraphQlTester tester) {
         final UUID courseId = UUID.randomUUID();
 
         // create admin user object
@@ -171,7 +171,7 @@ void updateMembershipTest(HttpGraphQlTester tester) {
     }
 
     @Test
-    void deleteNotExistingMembershipTest(HttpGraphQlTester tester) {
+    void deleteNotExistingMembershipTest(WebGraphQlTester tester) {
         final UUID courseId = UUID.randomUUID();
 
         // create admin user object
@@ -220,7 +220,7 @@ void deleteNotExistingMembershipTest(HttpGraphQlTester tester) {
     }
 
     @Test
-    void deleteMembershipTest(HttpGraphQlTester tester) {
+    void deleteMembershipTest(WebGraphQlTester tester) {
         final UUID courseId = UUID.randomUUID();
 
         // create admin user object
diff --git a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationCreateChapterTest.java b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationCreateChapterTest.java
index 5b2c7fc..70e4c05 100644
--- a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationCreateChapterTest.java
+++ b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationCreateChapterTest.java
@@ -5,13 +5,15 @@
 import de.unistuttgart.iste.meitrex.common.user_handling.LoggedInUser;
 import de.unistuttgart.iste.meitrex.course_service.persistence.entity.ChapterEntity;
 import de.unistuttgart.iste.meitrex.course_service.persistence.entity.CourseEntity;
-import de.unistuttgart.iste.meitrex.course_service.persistence.repository.*;
+import de.unistuttgart.iste.meitrex.course_service.persistence.repository.ChapterRepository;
+import de.unistuttgart.iste.meitrex.course_service.persistence.repository.CourseMembershipRepository;
+import de.unistuttgart.iste.meitrex.course_service.persistence.repository.CourseRepository;
 import de.unistuttgart.iste.meitrex.course_service.test_utils.TestUtils;
 import de.unistuttgart.iste.meitrex.generated.dto.Chapter;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.graphql.test.tester.GraphQlTester;
-import org.springframework.graphql.test.tester.HttpGraphQlTester;
+import org.springframework.graphql.test.tester.WebGraphQlTester;
 import org.springframework.test.context.ContextConfiguration;
 
 import java.time.OffsetDateTime;
@@ -40,7 +42,7 @@ class MutationCreateChapterTest {
      * Then the chapter is created and returned
      */
     @Test
-    void testCreateChapter(HttpGraphQlTester tester) {
+    void testCreateChapter(WebGraphQlTester tester) {
         final CourseEntity course = courseRepository.save(CourseEntity.builder()
                 .title("New Course")
                 .description("This is a new course")
@@ -106,7 +108,7 @@ void testCreateChapter(HttpGraphQlTester tester) {
      * Then an error is returned
      */
     @Test
-    void testCreateChapterCourseNotExisting(HttpGraphQlTester tester) {
+    void testCreateChapterCourseNotExisting(WebGraphQlTester tester) {
         final UUID courseId = UUID.randomUUID();
 
         // create admin user object
@@ -247,7 +249,7 @@ void testTooLongDescription(final GraphQlTester tester) {
      * Then a validation error is returned
      */
     @Test
-    void testStartDateAfterEndDate(HttpGraphQlTester tester) {
+    void testStartDateAfterEndDate(WebGraphQlTester tester) {
         final UUID courseId = UUID.randomUUID();
 
         // create admin user object
@@ -290,7 +292,7 @@ void testStartDateAfterEndDate(HttpGraphQlTester tester) {
      * Then a validation error is returned
      */
     @Test
-    void testSuggestedStartDateAfterEndDate(HttpGraphQlTester tester) {
+    void testSuggestedStartDateAfterEndDate(WebGraphQlTester tester) {
         final UUID courseId = UUID.randomUUID();
 
         // create admin user object
@@ -334,7 +336,7 @@ void testSuggestedStartDateAfterEndDate(HttpGraphQlTester tester) {
      * Then a validation error is returned
      */
     @Test
-    void testSuggestedStartDateAfterSuggestedEndDate(HttpGraphQlTester tester) {
+    void testSuggestedStartDateAfterSuggestedEndDate(WebGraphQlTester tester) {
         final UUID courseId = UUID.randomUUID();
 
         // create admin user object
@@ -379,7 +381,7 @@ void testSuggestedStartDateAfterSuggestedEndDate(HttpGraphQlTester tester) {
      * Then a validation error is returned
      */
     @Test
-    void testSuggestedStartDateBeforeStartDate(HttpGraphQlTester tester) {
+    void testSuggestedStartDateBeforeStartDate(WebGraphQlTester tester) {
         final UUID courseId = UUID.randomUUID();
 
         // create admin user object
@@ -423,7 +425,7 @@ void testSuggestedStartDateBeforeStartDate(HttpGraphQlTester tester) {
      * Then a validation error is returned
      */
     @Test
-    void testSuggestedEndDateBeforeStartDate(HttpGraphQlTester tester) {
+    void testSuggestedEndDateBeforeStartDate(WebGraphQlTester tester) {
         final UUID courseId = UUID.randomUUID();
 
         // create admin user object
@@ -467,7 +469,7 @@ void testSuggestedEndDateBeforeStartDate(HttpGraphQlTester tester) {
      * Then a validation error is returned
      */
     @Test
-    void testSuggestedEndDateAfterEndDate(HttpGraphQlTester tester) {
+    void testSuggestedEndDateAfterEndDate(WebGraphQlTester tester) {
         final UUID courseId = UUID.randomUUID();
 
         // create admin user object
diff --git a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationCreateCourseTest.java b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationCreateCourseTest.java
index 290f109..cd4bfc4 100644
--- a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationCreateCourseTest.java
+++ b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationCreateCourseTest.java
@@ -9,7 +9,6 @@
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.graphql.test.tester.GraphQlTester;
-import org.springframework.graphql.test.tester.HttpGraphQlTester;
 import org.springframework.test.context.ContextConfiguration;
 
 import java.time.OffsetDateTime;
diff --git a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationDeleteChapterTest.java b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationDeleteChapterTest.java
index 39fe578..90a5d11 100644
--- a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationDeleteChapterTest.java
+++ b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationDeleteChapterTest.java
@@ -9,11 +9,13 @@
 import de.unistuttgart.iste.meitrex.course_service.test_utils.TestUtils;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.graphql.test.tester.HttpGraphQlTester;
+import org.springframework.graphql.test.tester.WebGraphQlTester;
 import org.springframework.test.context.ContextConfiguration;
 
 import java.time.OffsetDateTime;
-import java.util.*;
+import java.util.Collections;
+import java.util.List;
+import java.util.UUID;
 import java.util.stream.Stream;
 
 import static org.hamcrest.MatcherAssert.assertThat;
@@ -39,7 +41,7 @@ class MutationDeleteChapterTest {
      * Then the chapter is deleted and the uuid is returned
      */
     @Test
-    void testDeletion(HttpGraphQlTester tester) {
+    void testDeletion(WebGraphQlTester tester) {
         // create a course in the database
         final var course = courseRepository.save(TestUtils.dummyCourseBuilder().build());
         // create two chapters in the database
@@ -81,7 +83,7 @@ void testDeletion(HttpGraphQlTester tester) {
      * Then an error is returned
      */
     @Test
-    void testDeletionInvalidId(HttpGraphQlTester tester) {
+    void testDeletionInvalidId(WebGraphQlTester tester) {
         final UUID chapterId = UUID.randomUUID();
 
         final String query = """
diff --git a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationDeleteCourseTest.java b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationDeleteCourseTest.java
index 285cdbf..5d97290 100644
--- a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationDeleteCourseTest.java
+++ b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationDeleteCourseTest.java
@@ -5,12 +5,14 @@
 import de.unistuttgart.iste.meitrex.common.user_handling.LoggedInUser;
 import de.unistuttgart.iste.meitrex.common.user_handling.LoggedInUser.UserRoleInCourse;
 import de.unistuttgart.iste.meitrex.course_service.persistence.entity.CourseEntity;
-import de.unistuttgart.iste.meitrex.course_service.persistence.repository.*;
+import de.unistuttgart.iste.meitrex.course_service.persistence.repository.ChapterRepository;
+import de.unistuttgart.iste.meitrex.course_service.persistence.repository.CourseMembershipRepository;
+import de.unistuttgart.iste.meitrex.course_service.persistence.repository.CourseRepository;
 import de.unistuttgart.iste.meitrex.course_service.test_utils.TestUtils;
 import org.hamcrest.MatcherAssert;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.graphql.test.tester.HttpGraphQlTester;
+import org.springframework.graphql.test.tester.WebGraphQlTester;
 import org.springframework.test.context.ContextConfiguration;
 
 import java.util.List;
@@ -41,7 +43,7 @@ class MutationDeleteCourseTest {
      * Then the course is deleted and the uuid is returned
      */
     @Test
-    void testDeletion(HttpGraphQlTester tester) {
+    void testDeletion(WebGraphQlTester tester) {
         // create two courses in the database
         final List<CourseEntity> initialCourses = Stream.of(
                         TestUtils.dummyCourseBuilder().title("Course 1").build(),
@@ -84,7 +86,7 @@ void testDeletion(HttpGraphQlTester tester) {
      * Then an error is returned
      */
     @Test
-    void testDeletionInvalidId(HttpGraphQlTester tester) {
+    void testDeletionInvalidId(WebGraphQlTester tester) {
         final UUID courseId = UUID.randomUUID();
 
         // create admin user object
diff --git a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationJoinCourseTest.java b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationJoinCourseTest.java
index ff73bff..cfa233f 100644
--- a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationJoinCourseTest.java
+++ b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationJoinCourseTest.java
@@ -2,13 +2,14 @@
 
 import de.unistuttgart.iste.meitrex.common.testutil.GraphQlApiTest;
 import de.unistuttgart.iste.meitrex.common.testutil.InjectCurrentUserHeader;
-import de.unistuttgart.iste.meitrex.course_service.persistence.entity.*;
+import de.unistuttgart.iste.meitrex.course_service.persistence.entity.CourseEntity;
+import de.unistuttgart.iste.meitrex.course_service.persistence.entity.CourseMembershipEntity;
+import de.unistuttgart.iste.meitrex.course_service.persistence.entity.CourseMembershipPk;
 import de.unistuttgart.iste.meitrex.course_service.persistence.repository.CourseMembershipRepository;
 import de.unistuttgart.iste.meitrex.course_service.persistence.repository.CourseRepository;
 import de.unistuttgart.iste.meitrex.generated.dto.UserRoleInCourse;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.graphql.test.tester.HttpGraphQlTester;
 
 import java.time.OffsetDateTime;
 import java.util.UUID;
diff --git a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationLeaveCourseTest.java b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationLeaveCourseTest.java
index 3673d9b..d9e8926 100644
--- a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationLeaveCourseTest.java
+++ b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationLeaveCourseTest.java
@@ -2,7 +2,9 @@
 
 import de.unistuttgart.iste.meitrex.common.testutil.GraphQlApiTest;
 import de.unistuttgart.iste.meitrex.common.testutil.InjectCurrentUserHeader;
-import de.unistuttgart.iste.meitrex.course_service.persistence.entity.*;
+import de.unistuttgart.iste.meitrex.course_service.persistence.entity.CourseEntity;
+import de.unistuttgart.iste.meitrex.course_service.persistence.entity.CourseMembershipEntity;
+import de.unistuttgart.iste.meitrex.course_service.persistence.entity.CourseMembershipPk;
 import de.unistuttgart.iste.meitrex.course_service.persistence.repository.CourseMembershipRepository;
 import de.unistuttgart.iste.meitrex.course_service.persistence.repository.CourseRepository;
 import de.unistuttgart.iste.meitrex.generated.dto.CourseMembership;
@@ -10,7 +12,6 @@
 import org.assertj.core.api.Assertions;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
-import org.springframework.graphql.test.tester.HttpGraphQlTester;
 
 import java.time.OffsetDateTime;
 import java.util.UUID;
diff --git a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationUpdateChapterTest.java b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationUpdateChapterTest.java
index b3ebaa4..fa73aea 100644
--- a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationUpdateChapterTest.java
+++ b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationUpdateChapterTest.java
@@ -5,17 +5,21 @@
 import de.unistuttgart.iste.meitrex.common.user_handling.LoggedInUser;
 import de.unistuttgart.iste.meitrex.course_service.persistence.entity.ChapterEntity;
 import de.unistuttgart.iste.meitrex.course_service.persistence.entity.CourseEntity;
-import de.unistuttgart.iste.meitrex.course_service.persistence.repository.*;
+import de.unistuttgart.iste.meitrex.course_service.persistence.repository.ChapterRepository;
+import de.unistuttgart.iste.meitrex.course_service.persistence.repository.CourseMembershipRepository;
+import de.unistuttgart.iste.meitrex.course_service.persistence.repository.CourseRepository;
 import de.unistuttgart.iste.meitrex.course_service.test_utils.TestUtils;
 import de.unistuttgart.iste.meitrex.generated.dto.Chapter;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.graphql.test.tester.GraphQlTester;
-import org.springframework.graphql.test.tester.HttpGraphQlTester;
+import org.springframework.graphql.test.tester.WebGraphQlTester;
 import org.springframework.test.context.ContextConfiguration;
 
 import java.time.OffsetDateTime;
-import java.util.*;
+import java.util.Collections;
+import java.util.Objects;
+import java.util.UUID;
 
 import static de.unistuttgart.iste.meitrex.common.testutil.HeaderUtils.addCurrentUserHeader;
 import static de.unistuttgart.iste.meitrex.common.testutil.TestUsers.userWithMembershipInCourseWithId;
@@ -39,7 +43,7 @@ class MutationUpdateChapterTest {
      * Then the chapter is updated and returned
      */
     @Test
-    void testUpdateChapter(HttpGraphQlTester tester) {
+    void testUpdateChapter(WebGraphQlTester tester) {
         final CourseEntity course = courseRepository.save(CourseEntity.builder()
                 .title("New Course")
                 .description("This is a new course")
@@ -114,7 +118,7 @@ void testUpdateChapter(HttpGraphQlTester tester) {
      * Then an error is returned
      */
     @Test
-    void testUpdateChapterNotExisting(HttpGraphQlTester tester) {
+    void testUpdateChapterNotExisting(WebGraphQlTester tester) {
         // create admin user object
         final LoggedInUser adminUser = new LoggedInUser(UUID.randomUUID(),
                 "admin",
@@ -257,7 +261,7 @@ void testTooLongDescription(final GraphQlTester tester) {
      * Then a validation error is returned
      */
     @Test
-    void testStartDateAfterEndDate(HttpGraphQlTester tester) {
+    void testStartDateAfterEndDate(WebGraphQlTester tester) {
         // create and save chapter
         final ChapterEntity chapter = chapterRepository.save(TestUtils.dummyChapterBuilder().build());
 
diff --git a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationUpdateCourseTest.java b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationUpdateCourseTest.java
index c8788b9..a7292cc 100644
--- a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationUpdateCourseTest.java
+++ b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/MutationUpdateCourseTest.java
@@ -5,14 +5,16 @@
 import de.unistuttgart.iste.meitrex.common.user_handling.LoggedInUser;
 import de.unistuttgart.iste.meitrex.course_service.persistence.entity.ChapterEntity;
 import de.unistuttgart.iste.meitrex.course_service.persistence.entity.CourseEntity;
-import de.unistuttgart.iste.meitrex.course_service.persistence.repository.*;
+import de.unistuttgart.iste.meitrex.course_service.persistence.repository.ChapterRepository;
+import de.unistuttgart.iste.meitrex.course_service.persistence.repository.CourseMembershipRepository;
+import de.unistuttgart.iste.meitrex.course_service.persistence.repository.CourseRepository;
 import de.unistuttgart.iste.meitrex.course_service.test_utils.TestUtils;
 import de.unistuttgart.iste.meitrex.generated.dto.Chapter;
 import de.unistuttgart.iste.meitrex.generated.dto.YearDivision;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.graphql.test.tester.GraphQlTester;
-import org.springframework.graphql.test.tester.HttpGraphQlTester;
+import org.springframework.graphql.test.tester.WebGraphQlTester;
 import org.springframework.test.context.ContextConfiguration;
 import org.springframework.transaction.annotation.Transactional;
 
@@ -47,7 +49,7 @@ class MutationUpdateCourseTest {
      */
     @Test
     @Transactional
-    void testUpdateCourseSuccessful(HttpGraphQlTester tester) {
+    void testUpdateCourseSuccessful(WebGraphQlTester tester) {
         // create a course with a chapter in the database
         final CourseEntity initialCourse = courseRepository.save(CourseEntity.builder().title("Course 1")
                 .description("This is course 1")
@@ -138,7 +140,7 @@ void testUpdateCourseSuccessful(HttpGraphQlTester tester) {
      * Then an error is returned
      */
     @Test
-    void testUpdateCourseNotExisting(HttpGraphQlTester tester) {
+    void testUpdateCourseNotExisting(WebGraphQlTester tester) {
         final UUID courseId = UUID.randomUUID();
 
         // create admin user object
@@ -272,7 +274,7 @@ void testTooLongDescription(final GraphQlTester tester) {
      * Then a validation error is returned
      */
     @Test
-    void testStartDateAfterEndDate(HttpGraphQlTester tester) {
+    void testStartDateAfterEndDate(WebGraphQlTester tester) {
         final UUID courseId = UUID.randomUUID();
 
         // create admin user object
diff --git a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/QueryCourseMembershipsTest.java b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/QueryCourseMembershipsTest.java
index 351b52b..a38c422 100644
--- a/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/QueryCourseMembershipsTest.java
+++ b/src/test/java/de/unistuttgart/iste/meitrex/course_service/api/QueryCourseMembershipsTest.java
@@ -7,14 +7,18 @@
 import de.unistuttgart.iste.meitrex.course_service.persistence.entity.CourseMembershipEntity;
 import de.unistuttgart.iste.meitrex.course_service.persistence.repository.CourseMembershipRepository;
 import de.unistuttgart.iste.meitrex.course_service.persistence.repository.CourseRepository;
-import de.unistuttgart.iste.meitrex.generated.dto.*;
+import de.unistuttgart.iste.meitrex.generated.dto.Course;
+import de.unistuttgart.iste.meitrex.generated.dto.CourseMembership;
+import de.unistuttgart.iste.meitrex.generated.dto.UserRoleInCourse;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.graphql.test.tester.GraphQlTester;
-import org.springframework.graphql.test.tester.HttpGraphQlTester;
+import org.springframework.graphql.test.tester.WebGraphQlTester;
 
 import java.time.OffsetDateTime;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.UUID;
 
 import static de.unistuttgart.iste.meitrex.common.testutil.HeaderUtils.addCurrentUserHeader;
 import static de.unistuttgart.iste.meitrex.common.testutil.TestUsers.userWithMembershipInCourseWithId;
@@ -74,7 +78,7 @@ void testMembership(final GraphQlTester tester) {
     }
 
     @Test
-    void testMembershipsFieldInCourse(HttpGraphQlTester tester) {
+    void testMembershipsFieldInCourse(WebGraphQlTester tester) {
         final CourseEntity course = courseRepository.save(createTestCourse());
 
         final LoggedInUser currentUser = userWithMembershipInCourseWithId(course.getId(), ADMINISTRATOR);
@@ -110,7 +114,7 @@ void testMembershipsFieldInCourse(HttpGraphQlTester tester) {
     }
 
     @Test
-    void testMembershipsFieldInCourseNoPermission(HttpGraphQlTester tester) {
+    void testMembershipsFieldInCourseNoPermission(WebGraphQlTester tester) {
         final CourseEntity course = courseRepository.save(createTestCourse());
 
         final LoggedInUser currentUser = userWithMembershipInCourseWithId(course.getId(), STUDENT);