Exam mode: Add exam rescheduled event

src/main/java/de/tum/cit/aet/artemis/exam/domain/event/ExamRescheduledEvent.java

@@ -0,0 +1,50 @@
+package de.tum.cit.aet.artemis.exam.domain.event;
+
+import java.time.ZonedDateTime;
+
+import jakarta.persistence.Column;
+import jakarta.persistence.DiscriminatorValue;
+import jakarta.persistence.Entity;
+
+import de.tum.cit.aet.artemis.exam.dto.examevent.ExamRescheduledEventDTO;
+
+/**
+ * An event indicating that the exam's start and end dates have been rescheduled. The working time remains unchanged in such cases.
+ */
+@Entity
+@DiscriminatorValue(value = "R")
+public class ExamRescheduledEvent extends ExamLiveEvent {
+
+    /**
+     * The new start date
+     */
+    @Column(name = "newStartDate")
+    private ZonedDateTime newStartDate;
+
+    /**
+     * The new end date
+     */
+    @Column(name = "newEndDate")
+    private ZonedDateTime newEndDate;
+
+    public ZonedDateTime getNewStartDate() {
+        return newStartDate;
+    }
+
+    public void setNewStartDate(ZonedDateTime newStartDate) {
+        this.newStartDate = newStartDate;
+    }
+
+    public ZonedDateTime getNewEndDate() {
+        return newEndDate;
+    }
+
+    public void setNewEndDate(ZonedDateTime newEndDate) {
+        this.newEndDate = newEndDate;
+    }
+
+    @Override
+    public ExamRescheduledEventDTO asDTO() {
+        return new ExamRescheduledEventDTO(this.getId(), this.getCreatedBy(), this.getCreatedDate(), newStartDate, newEndDate);
+    }
+}

src/main/java/de/tum/cit/aet/artemis/exam/dto/examevent/ExamLiveEventBaseDTO.java

@@ -17,6 +17,7 @@
     @JsonSubTypes.Type(value = WorkingTimeUpdateEventDTO.class, name = "workingTimeUpdate"),
     @JsonSubTypes.Type(value = ExamAttendanceCheckEventDTO.class, name = "examAttendanceCheck"),
     @JsonSubTypes.Type(value = ProblemStatementUpdateEventDTO.class, name = "problemStatementUpdate"),
+    @JsonSubTypes.Type(value = ExamRescheduledEventDTO.class, name = "examRescheduled"),
 })
 // @formatter:on
 public interface ExamLiveEventBaseDTO {

src/main/java/de/tum/cit/aet/artemis/exam/dto/examevent/ExamRescheduledEventDTO.java

@@ -0,0 +1,16 @@
+package de.tum.cit.aet.artemis.exam.dto.examevent;
+
+import java.time.Instant;
+import java.time.ZonedDateTime;
+
+import com.fasterxml.jackson.annotation.JsonInclude;
+
+import de.tum.cit.aet.artemis.exam.domain.event.ExamRescheduledEvent;
+
+/**
+ * A DTO for the {@link ExamRescheduledEvent} entity.
+ */
+@JsonInclude(JsonInclude.Include.NON_EMPTY)
+public record ExamRescheduledEventDTO(Long id, String createdBy, Instant createdDate, ZonedDateTime newStartDate, ZonedDateTime newEndDate) implements ExamLiveEventBaseDTO {
+
+}

src/main/java/de/tum/cit/aet/artemis/exam/service/ExamLiveEventsService.java

@@ -12,6 +12,7 @@
 import de.tum.cit.aet.artemis.exam.domain.StudentExam;
 import de.tum.cit.aet.artemis.exam.domain.event.ExamAttendanceCheckEvent;
 import de.tum.cit.aet.artemis.exam.domain.event.ExamLiveEvent;
+import de.tum.cit.aet.artemis.exam.domain.event.ExamRescheduledEvent;
 import de.tum.cit.aet.artemis.exam.domain.event.ExamWideAnnouncementEvent;
 import de.tum.cit.aet.artemis.exam.domain.event.ProblemStatementUpdateEvent;
 import de.tum.cit.aet.artemis.exam.domain.event.WorkingTimeUpdateEvent;
@@ -129,6 +130,28 @@ public void createAndSendWorkingTimeUpdateEvent(StudentExam studentExam, int new
         this.storeAndDistributeLiveExamEvent(event);
     }
 
+    /**
+     * Send an exam rescheduled update to the specified student.
+     *
+     * @param studentExam The student exam the dates rescheduled for
+     * @param sentBy      The user who performed the update
+     */
+    public void createAndSendExamRescheduledEvent(StudentExam studentExam, User sentBy) {
+        var event = new ExamRescheduledEvent();
+
+        // Common fields
+        event.setExamId(studentExam.getExam().getId());
+        event.setStudentExamId(studentExam.getId());
+        event.setCreatedBy(sentBy.getName());
+
+        // Specific fields
+        event.setNewStartDate(studentExam.getExam().getStartDate());
+        event.setNewEndDate(studentExam.getExam().getEndDate());
+
+        this.storeAndDistributeLiveExamEvent(event);
+
+    }
+
     /**
      * Send a problem statement update to all affected students.
      *

src/main/java/de/tum/cit/aet/artemis/exam/service/ExamService.java

@@ -1445,9 +1445,17 @@ public void updateStudentExamsAndRescheduleExercises(Exam exam, int originalExam
                 studentExam.setWorkingTime(adjustedWorkingTime);
             }
 
-            // NOTE: if the exam is already visible, notify the student about the working time change
+            // "NOTE: If the exam is already visible, notify the student about any changes to the working time or exam schedule."
             if (now.isAfter(exam.getVisibleDate())) {
-                examLiveEventsService.createAndSendWorkingTimeUpdateEvent(studentExam, studentExam.getWorkingTime(), originalStudentWorkingTime, true, instructor);
+                // If the old working time equals the new working time, the exam has been rescheduled
+                if (studentExam.getWorkingTime().equals(originalStudentWorkingTime)) {
+                    if (now.isBefore(exam.getStartDate())) {
+                        examLiveEventsService.createAndSendExamRescheduledEvent(studentExam, instructor);
+                    }
+                }
+                else {
+                    examLiveEventsService.createAndSendWorkingTimeUpdateEvent(studentExam, studentExam.getWorkingTime(), originalStudentWorkingTime, true, instructor);
+                }
             }
         }
         studentExamRepository.saveAll(studentExams);

src/main/resources/config/liquibase/changelog/20241211131711_changelog.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<databaseChangeLog xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
+                   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+                   xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog https://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-latest.xsd">
+    <changeSet id="20241211131711" author="mkawka">
+        <addColumn tableName="exam_live_event">
+            <column name="new_start_date" type="datetime(3)"/>
+            <column name="new_end_date" type="datetime(3)"/>
+        </addColumn>
+    </changeSet>
+</databaseChangeLog>

src/main/resources/config/liquibase/master.xml

@@ -41,6 +41,7 @@
     <include file="classpath:config/liquibase/changelog/20241114122713_changelog.xml" relativeToChangelogFile="false"/>
     <include file="classpath:config/liquibase/changelog/20241119191919_changelog.xml" relativeToChangelogFile="false"/>
     <include file="classpath:config/liquibase/changelog/20241125000900_changelog.xml" relativeToChangelogFile="false"/>
+    <include file="classpath:config/liquibase/changelog/20241211131711_changelog.xml" relativeToChangelogFile="false"/>
 
     <!-- NOTE: please use the format "YYYYMMDDhhmmss_changelog.xml", i.e. year month day hour minutes seconds and not something else! -->
     <!-- we should also stay in a chronological order! -->

src/main/webapp/app/exam/participate/events/exam-live-events-button.component.ts

@@ -12,8 +12,14 @@ export const USER_DISPLAY_RELEVANT_EVENTS = [
     ExamLiveEventType.WORKING_TIME_UPDATE,
     ExamLiveEventType.EXAM_ATTENDANCE_CHECK,
     ExamLiveEventType.PROBLEM_STATEMENT_UPDATE,
+    ExamLiveEventType.EXAM_RESCHEDULED,
+];
+export const USER_DISPLAY_RELEVANT_EVENTS_REOPEN = [
+    ExamLiveEventType.EXAM_WIDE_ANNOUNCEMENT,
+    ExamLiveEventType.WORKING_TIME_UPDATE,
+    ExamLiveEventType.PROBLEM_STATEMENT_UPDATE,
+    ExamLiveEventType.EXAM_RESCHEDULED,
 ];
-export const USER_DISPLAY_RELEVANT_EVENTS_REOPEN = [ExamLiveEventType.EXAM_WIDE_ANNOUNCEMENT, ExamLiveEventType.WORKING_TIME_UPDATE, ExamLiveEventType.PROBLEM_STATEMENT_UPDATE];
 
 @Component({
     selector: 'jhi-exam-live-events-button',

src/main/webapp/app/exam/participate/exam-participation-live-events.service.ts

@@ -20,6 +20,7 @@ export enum ExamLiveEventType {
     WORKING_TIME_UPDATE = 'workingTimeUpdate',
     EXAM_ATTENDANCE_CHECK = 'examAttendanceCheck',
     PROBLEM_STATEMENT_UPDATE = 'problemStatementUpdate',
+    EXAM_RESCHEDULED = 'examRescheduled',
 }
 
 export type ExamLiveEvent = {
@@ -52,6 +53,11 @@ export type ProblemStatementUpdateEvent = ExamLiveEvent & {
     exerciseName: string;
 };
 
+export type ExamRescheduledEvent = ExamLiveEvent & {
+    newStartDate: dayjs.Dayjs;
+    newEndDate: dayjs.Dayjs;
+};
+
 @Injectable({ providedIn: 'root' })
 export class ExamParticipationLiveEventsService {
     private courseId?: number;
@@ -186,6 +192,10 @@ export class ExamParticipationLiveEventsService {
             this.events = events;
             this.events.forEach((event) => {
                 event.createdDate = convertDateFromServer(event.createdDate)!;
+                // The "Exam Rescheduled" event should not trigger the event overlay if the student navigates to the exam page after it has been sent
+                if (event.eventType === ExamLiveEventType.EXAM_RESCHEDULED) {
+                    this.acknowledgeEvent(event, true);
+                }
             });
 
             // Replay events so unacknowledged events can be processed

src/main/webapp/app/exam/participate/exam-participation.component.ts

@@ -39,12 +39,14 @@ import { ExamManagementService } from 'app/exam/manage/exam-management.service';
 import {
     ExamLiveEventType,
     ExamParticipationLiveEventsService,
+    ExamRescheduledEvent,
     ProblemStatementUpdateEvent,
     WorkingTimeUpdateEvent,
 } from 'app/exam/participate/exam-participation-live-events.service';
 import { ExamExerciseUpdateService } from 'app/exam/manage/exam-exercise-update.service';
 import { ProfileService } from 'app/shared/layouts/profiles/profile.service';
 import { SidebarCardElement, SidebarData } from 'app/types/sidebar';
+import { convertDateFromServer } from 'app/utils/date.utils';
 
 type GenerateParticipationStatus = 'generating' | 'failed' | 'success';
 
@@ -102,6 +104,7 @@ export class ExamParticipationComponent implements OnInit, OnDestroy, ComponentC
     errorSubscription: Subscription;
     websocketSubscription?: Subscription;
     workingTimeUpdateEventsSubscription?: Subscription;
+    examRescheduledEventsSubscription?: Subscription;
     problemStatementUpdateEventsSubscription?: Subscription;
     profileSubscription?: Subscription;
 
@@ -316,6 +319,7 @@ export class ExamParticipationComponent implements OnInit, OnDestroy, ComponentC
                     });
                 }
             });
+            this.examRescheduledEventsSubscription?.unsubscribe();
             this.subscribeToProblemStatementUpdates();
             this.initializeOverviewPage();
         }
@@ -576,6 +580,7 @@ export class ExamParticipationComponent implements OnInit, OnDestroy, ComponentC
         this.errorSubscription.unsubscribe();
         this.websocketSubscription?.unsubscribe();
         this.workingTimeUpdateEventsSubscription?.unsubscribe();
+        this.examRescheduledEventsSubscription?.unsubscribe();
         this.problemStatementUpdateEventsSubscription?.unsubscribe();
         this.examParticipationService.resetExamLayout();
         this.profileSubscription?.unsubscribe();
@@ -589,6 +594,9 @@ export class ExamParticipationComponent implements OnInit, OnDestroy, ComponentC
         if (!this.exam.testExam) {
             this.initIndividualEndDates(this.exam.startDate!);
         }
+        if (this.serverDateService.now().isBefore(this.exam.startDate)) {
+            this.subscribeToExamRescheduledEvents();
+        }
 
         // only show the summary if the student was able to submit on time.
         if (this.isOver() && this.studentExam.submitted) {
@@ -655,6 +663,21 @@ export class ExamParticipationComponent implements OnInit, OnDestroy, ComponentC
             });
     }
 
+    private subscribeToExamRescheduledEvents() {
+        if (this.examRescheduledEventsSubscription) {
+            this.examRescheduledEventsSubscription.unsubscribe();
+        }
+        this.examRescheduledEventsSubscription = this.liveEventsService.observeNewEventsAsSystem([ExamLiveEventType.EXAM_RESCHEDULED]).subscribe((event: ExamRescheduledEvent) => {
+            // Create new object to make change detection work, otherwise the dates will not update
+            const startDate = convertDateFromServer(event.newStartDate);
+            const endDate = convertDateFromServer(event.newEndDate);
+            this.exam = { ...this.exam, startDate: startDate, endDate: endDate };
+            this.individualStudentEndDate = dayjs(this.exam.startDate).add(this.studentExam.workingTime!, 'seconds');
+            this.individualStudentEndDateWithGracePeriod = this.individualStudentEndDate.clone().add(this.exam.gracePeriod!, 'seconds');
+            this.liveEventsService.acknowledgeEvent(event, false);
+        });
+    }
+
     private subscribeToProblemStatementUpdates() {
         if (this.problemStatementUpdateEventsSubscription) {
             this.problemStatementUpdateEventsSubscription.unsubscribe();

src/main/webapp/app/exam/participate/exam-start-information/exam-start-information.component.ts

@@ -1,4 +1,4 @@
-import { Component, Input, OnInit } from '@angular/core';
+import { Component, Input, OnChanges, OnInit } from '@angular/core';
 import { ArtemisSharedModule } from 'app/shared/shared.module';
 import { ArtemisSharedComponentModule } from 'app/shared/components/shared-component.module';
 import { InformationBox, InformationBoxComponent, InformationBoxContent } from 'app/shared/information-box/information-box.component';
@@ -14,7 +14,7 @@ import { SafeHtml } from '@angular/platform-browser';
     imports: [ArtemisSharedModule, ArtemisSharedComponentModule, InformationBoxComponent, ArtemisExamSharedModule],
     templateUrl: './exam-start-information.component.html',
 })
-export class ExamStartInformationComponent implements OnInit {
+export class ExamStartInformationComponent implements OnInit, OnChanges {
     examInformationBoxData: InformationBox[] = [];
 
     @Input() exam: Exam;
@@ -32,6 +32,23 @@ export class ExamStartInformationComponent implements OnInit {
     gracePeriodInMinutes?: number;
 
     ngOnInit(): void {
+        this.updateInformationBoxes();
+    }
+
+    ngOnChanges(): void {
+        this.updateInformationBoxes();
+    }
+
+    buildInformationBox(boxTitle: string, boxContent: InformationBoxContent, isContentComponent = false): InformationBox {
+        const examInformationBoxData: InformationBox = {
+            title: boxTitle ?? '',
+            content: boxContent,
+            isContentComponent: isContentComponent,
+        };
+        return examInformationBoxData;
+    }
+
+    private updateInformationBoxes(): void {
         this.totalPoints = this.exam.examMaxPoints;
         this.totalWorkingTimeInMinutes = Math.floor(this.exam.workingTime! / 60);
         this.moduleNumber = this.exam.moduleNumber;
@@ -42,18 +59,10 @@ export class ExamStartInformationComponent implements OnInit {
         this.startDate = this.exam.startDate;
         this.gracePeriodInMinutes = Math.floor(this.exam.gracePeriod! / 60);
 
+        this.examInformationBoxData = [];
         this.prepareInformationBoxData();
     }
 
-    buildInformationBox(boxTitle: string, boxContent: InformationBoxContent, isContentComponent = false): InformationBox {
-        const examInformationBoxData: InformationBox = {
-            title: boxTitle ?? '',
-            content: boxContent,
-            isContentComponent: isContentComponent,
-        };
-        return examInformationBoxData;
-    }
-
     prepareInformationBoxData(): void {
         if (this.moduleNumber) {
             const boxContentModuleNumber: InformationBoxContent = {

src/main/webapp/app/exam/shared/events/exam-live-event.component.html

@@ -71,6 +71,15 @@
                     }
                 </div>
             }
+            @case (ExamLiveEventType.EXAM_RESCHEDULED) {
+                <div>
+                    <div
+                        [jhiTranslate]="'artemisApp.exam.events.messages.examRescheduled.description'"
+                        [translateValues]="{ startDate: examRescheduledEvent.newStartDate | artemisDate, endDate: examRescheduledEvent.newEndDate | artemisDate }"
+                        class="wt-title"
+                    ></div>
+                </div>
+            }
         }
     </div>
     <div class="d-flex gap-2">

src/main/webapp/app/exam/shared/events/exam-live-event.component.scss

@@ -44,6 +44,18 @@
         border-color: var(--artemis-alert-info-border);
     }
 
+    &.examRescheduled {
+        background-color: var(--artemis-alert-warning-background);
+        border-color: var(--artemis-alert-warning-border);
+
+        .wt-title {
+            font-weight: bold;
+            font-size: 1.5em;
+            text-align: center;
+            margin-bottom: 15px;
+        }
+    }
+
     .headline {
         display: flex;
         justify-content: space-between;

src/main/webapp/app/exam/shared/events/exam-live-event.component.ts

@@ -4,6 +4,7 @@ import {
     ExamAttendanceCheckEvent,
     ExamLiveEvent,
     ExamLiveEventType,
+    ExamRescheduledEvent,
     ExamWideAnnouncementEvent,
     ProblemStatementUpdateEvent,
     WorkingTimeUpdateEvent,
@@ -50,6 +51,10 @@ export class ExamLiveEventComponent {
         return this.event as ProblemStatementUpdateEvent;
     }
 
+    get examRescheduledEvent(): ExamRescheduledEvent {
+        return this.event as ExamRescheduledEvent;
+    }
+
     acknowledgeEvent() {
         this.onAcknowledge.emit(this.event);
     }