Development: Tune data export test to prevent flakyness

src/test/java/de/tum/in/www1/artemis/science/ScienceUtilService.java

@@ -23,11 +23,12 @@ public class ScienceUtilService {
      * @param identity   The login of the user associated with the event.
      * @param type       The type of the event.
      * @param resourceId The id of the resource associated with the event.
+     * @param timestamp  The timestamp of the event.
      */
-    public ScienceEvent createScienceEvent(String identity, ScienceEventType type, Long resourceId) {
+    public ScienceEvent createScienceEvent(String identity, ScienceEventType type, Long resourceId, ZonedDateTime timestamp) {
         ScienceEvent event = new ScienceEvent();
         event.setIdentity(identity);
-        event.setTimestamp(ZonedDateTime.now());
+        event.setTimestamp(timestamp);
         event.setType(type);
         event.setResourceId(resourceId);
         return scienceEventRepository.save(event);
@@ -39,14 +40,7 @@ public ScienceEvent createScienceEvent(String identity, ScienceEventType type, L
      */
     public static Comparator<ScienceEvent> scienceEventComparator = Comparator.comparing(ScienceEvent::getResourceId).thenComparing(ScienceEvent::getType)
             .thenComparing((ScienceEvent e1, ScienceEvent e2) -> {
-
-                Duration d = Duration.between(e1.getTimestamp(), e2.getTimestamp());
-                if (d.toNanos() > 500) {
-                    return 1;
-                }
-                else if (d.toNanos() < -500) {
-                    return -1;
-                }
-                return 0;
-            });
+                Duration duration = Duration.between(e1.getTimestamp(), e2.getTimestamp());
+                return Math.abs(duration.toNanos()) < 1e5 ? 0 : duration.isNegative() ? -1 : 1;
+            }).thenComparing(ScienceEvent::getIdentity);
 }

src/test/java/de/tum/in/www1/artemis/service/DataExportCreationServiceTest.java

@@ -167,7 +167,8 @@ void initTestCase() throws IOException {
 
         apollonRequestMockProvider.enableMockingOfRequests();
 
-        // mock apollon conversion 8 times, because the last test includes 8 modeling exercises, because each test adds modeling exercises
+        // mock apollon conversion 8 times, because the last test includes 8 modeling
+        // exercises, because each test adds modeling exercises
         for (int i = 0; i < 8; i++) {
             mockApollonConversion();
         }
@@ -230,7 +231,6 @@ private void assertCommunicationDataCsvFile(Path courseDirPath) {
     /**
      * Asserts the content of the science events CSV file.
      * Allows for a 500ns difference between the timestamps due to the reimport from the csv export.
-     * Might cause the test to be flaky if multiple events are created overlapping and matched wrongly.
      *
      * @param extractedZipDirPath The path to the extracted zip directory
      * @param events              The set of science events to compare with the content of the CSV file
@@ -249,13 +249,13 @@ private void assertScienceEventsCSVFile(Path extractedZipDirPath, Set<ScienceEve
                 scienceEvent.setTimestamp(ZonedDateTime.parse(record.get("timestamp")));
                 scienceEvent.setType(ScienceEventType.valueOf(record.get("event_type")));
                 scienceEvent.setResourceId(Long.parseLong(record.get("resource_id")));
+                scienceEvent.setIdentity(TEST_PREFIX + "student1");
                 actual.add(scienceEvent);
             }
         }
         catch (IOException e) {
             fail("Failed while reading science events CSV file");
         }
-
         assertThat(actual).usingElementComparator(ScienceUtilService.scienceEventComparator).containsExactlyInAnyOrderElementsOf(events);
     }
 
@@ -332,9 +332,13 @@ private void createPlagiarismData(String userLogin, ProgrammingExercise programm
     }
 
     private Set<ScienceEvent> createScienceEvents(String userLogin) {
-        return Set.of(scienceUtilService.createScienceEvent(userLogin, ScienceEventType.EXERCISE__OPEN, 1L),
-                scienceUtilService.createScienceEvent(userLogin, ScienceEventType.LECTURE__OPEN, 2L),
-                scienceUtilService.createScienceEvent(userLogin, ScienceEventType.LECTURE__OPEN_UNIT, 3L));
+
+        ZonedDateTime timestamp = ZonedDateTime.now();
+        // Rounding timestamp due to rounding during export
+        timestamp = timestamp.withNano(timestamp.getNano() - timestamp.getNano() % 10000);
+        return Set.of(scienceUtilService.createScienceEvent(userLogin, ScienceEventType.EXERCISE__OPEN, 1L, timestamp),
+                scienceUtilService.createScienceEvent(userLogin, ScienceEventType.LECTURE__OPEN, 2L, timestamp.plusMinutes(1)),
+                scienceUtilService.createScienceEvent(userLogin, ScienceEventType.LECTURE__OPEN_UNIT, 3L, timestamp.plusSeconds(30)));
 
     }
 
@@ -635,7 +639,8 @@ void testDataExportContainsDataAboutCourseStudentUnenrolled() throws Exception {
         var course = prepareCourseDataForDataExportCreation(assessmentDueDateInTheFuture, courseShortName);
         conversationUtilService.addOneMessageForUserInCourse(TEST_PREFIX + "student1", course, "only one post");
         var dataExport = initDataExport();
-        // by setting the course groups to a different value we simulate unenrollment because the user is no longer part of the user group and hence, the course.
+        // by setting the course groups to a different value, we simulate unenrollment
+        // because the user is no longer part of the user group and hence, the course.
         courseUtilService.updateCourseGroups("abc", course, "");
         dataExportCreationService.createDataExport(dataExport);
         var dataExportFromDb = dataExportRepository.findByIdElseThrow(dataExport.getId());