Learning paths: Add explanation view for learning path users

src/main/java/de/tum/cit/aet/artemis/atlas/domain/competency/LearningPath.java

@@ -31,6 +31,12 @@ public class LearningPath extends DomainObject {
     @Column(name = "progress")
     private int progress;
 
+    /**
+     * flag indicating if a student started the learning path
+     */
+    @Column(name = "started_by_student")
+    private boolean startedByStudent = false;
+
     @ManyToOne
     @JoinColumn(name = "user_id")
     private User user;
@@ -89,8 +95,16 @@ public void removeCompetency(CourseCompetency competency) {
         this.competencies.remove(competency);
     }
 
+    public boolean isStartedByStudent() {
+        return startedByStudent;
+    }
+
+    public void setStartedByStudent(boolean startedByStudent) {
+        this.startedByStudent = startedByStudent;
+    }
+
     @Override
     public String toString() {
-        return "LearningPath{" + "id=" + getId() + ", user=" + user + ", course=" + course + ", competencies=" + competencies + '}';
+        return "LearningPath{" + "id=" + getId() + ", user=" + user + ", course=" + course + ", competencies=" + competencies + ", startedByStudent=" + startedByStudent + "}";
     }
 }

src/main/java/de/tum/cit/aet/artemis/atlas/dto/LearningPathDTO.java

@@ -0,0 +1,13 @@
+package de.tum.cit.aet.artemis.atlas.dto;
+
+import com.fasterxml.jackson.annotation.JsonInclude;
+
+import de.tum.cit.aet.artemis.atlas.domain.competency.LearningPath;
+
+@JsonInclude(JsonInclude.Include.NON_EMPTY)
+public record LearningPathDTO(long id, boolean startedByStudent, int progress) {
+
+    public static LearningPathDTO of(LearningPath learningPath) {
+        return new LearningPathDTO(learningPath.getId(), learningPath.isStartedByStudent(), learningPath.getProgress());
+    }
+}

src/main/java/de/tum/cit/aet/artemis/atlas/service/learningpath/LearningPathService.java

@@ -11,6 +11,7 @@
 import java.util.stream.Collectors;
 
 import jakarta.validation.constraints.NotNull;
+import jakarta.ws.rs.BadRequestException;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -25,6 +26,7 @@
 import de.tum.cit.aet.artemis.atlas.dto.CompetencyGraphEdgeDTO;
 import de.tum.cit.aet.artemis.atlas.dto.CompetencyGraphNodeDTO;
 import de.tum.cit.aet.artemis.atlas.dto.LearningPathCompetencyGraphDTO;
+import de.tum.cit.aet.artemis.atlas.dto.LearningPathDTO;
 import de.tum.cit.aet.artemis.atlas.dto.LearningPathHealthDTO;
 import de.tum.cit.aet.artemis.atlas.dto.LearningPathInformationDTO;
 import de.tum.cit.aet.artemis.atlas.dto.LearningPathNavigationOverviewDTO;
@@ -243,6 +245,52 @@ private void updateLearningPathProgress(@NotNull LearningPath learningPath) {
         log.debug("Updated LearningPath (id={}) for user (id={})", learningPath.getId(), userId);
     }
 
+    /**
+     * Get the learning path for the current user in the given course.
+     *
+     * @param courseId the id of the course
+     * @return the learning path of the current user
+     */
+    public LearningPathDTO getLearningPathForCurrentUser(long courseId) {
+        final var currentUser = userRepository.getUser();
+        final var learningPath = learningPathRepository.findByCourseIdAndUserIdElseThrow(courseId, currentUser.getId());
+        return LearningPathDTO.of(learningPath);
+    }
+
+    /**
+     * Generate a learning path for the current user in the given course.
+     *
+     * @param courseId the id of the course
+     * @return the generated learning path
+     */
+    public LearningPathDTO generateLearningPathForCurrentUser(long courseId) {
+        final var currentUser = userRepository.getUser();
+        final var course = courseRepository.findWithEagerCompetenciesAndPrerequisitesByIdElseThrow(courseId);
+        if (learningPathRepository.findByCourseIdAndUserId(courseId, currentUser.getId()).isPresent()) {
+            throw new BadRequestException("Learning path already exists.");
+        }
+        final var learningPath = generateLearningPathForUser(course, currentUser);
+        return LearningPathDTO.of(learningPath);
+    }
+
+    /**
+     * Start the learning path for the current user in the given course.
+     *
+     * @param learningPathId the id of the learning path
+     */
+    public void startLearningPathForCurrentUser(long learningPathId) {
+        final var learningPath = learningPathRepository.findByIdElseThrow(learningPathId);
+        final var currentUser = userRepository.getUser();
+        if (!learningPath.getUser().equals(currentUser)) {
+            throw new AccessForbiddenException("You are not allowed to start this learning path.");
+        }
+        else if (learningPath.isStartedByStudent()) {
+            throw new BadRequestException("Learning path already started.");
+        }
+        learningPath.setStartedByStudent(true);
+        learningPathRepository.save(learningPath);
+    }
+
     /**
      * Gets the health status of learning paths for the given course.
      *

src/main/java/de/tum/cit/aet/artemis/atlas/web/LearningPathResource.java

@@ -17,6 +17,7 @@
 import org.springframework.context.annotation.Profile;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PatchMapping;
 import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.PutMapping;
@@ -28,6 +29,7 @@
 import de.tum.cit.aet.artemis.atlas.dto.CompetencyNameDTO;
 import de.tum.cit.aet.artemis.atlas.dto.CompetencyProgressForLearningPathDTO;
 import de.tum.cit.aet.artemis.atlas.dto.LearningPathCompetencyGraphDTO;
+import de.tum.cit.aet.artemis.atlas.dto.LearningPathDTO;
 import de.tum.cit.aet.artemis.atlas.dto.LearningPathHealthDTO;
 import de.tum.cit.aet.artemis.atlas.dto.LearningPathInformationDTO;
 import de.tum.cit.aet.artemis.atlas.dto.LearningPathNavigationDTO;
@@ -301,19 +303,31 @@ private ResponseEntity<NgxLearningPathDTO> getLearningPathNgx(@PathVariable long
     }
 
     /**
-     * GET courses/:courseId/learning-path-id : Gets the id of the learning path.
+     * GET courses/:courseId/learning-path/me : Gets the learning path of the current user in the course.
      *
-     * @param courseId the id of the course from which the learning path id should be fetched
-     * @return the ResponseEntity with status 200 (OK) and with body the id of the learning path
+     * @param courseId the id of the course for which the learning path should be fetched
+     * @return the ResponseEntity with status 200 (OK) and with body the learning path
      */
-    @GetMapping("courses/{courseId}/learning-path-id")
+    @GetMapping("courses/{courseId}/learning-path/me")
     @EnforceAtLeastStudentInCourse
-    public ResponseEntity<Long> getLearningPathId(@PathVariable long courseId) {
-        log.debug("REST request to get learning path id for course with id: {}", courseId);
+    public ResponseEntity<LearningPathDTO> getLearningPathForCurrentUser(@PathVariable long courseId) {
+        log.debug("REST request to get learning path of current user for course with id: {}", courseId);
         courseService.checkLearningPathsEnabledElseThrow(courseId);
-        User user = userRepository.getUser();
-        final var learningPath = learningPathRepository.findByCourseIdAndUserIdElseThrow(courseId, user.getId());
-        return ResponseEntity.ok(learningPath.getId());
+        return ResponseEntity.ok(learningPathService.getLearningPathForCurrentUser(courseId));
+    }
+
+    /**
+     * PATCH learning-path/:learningPathId/start : Starts the learning path for the current user.
+     *
+     * @param learningPathId the id of the learning path to start
+     * @return the ResponseEntity with status 204 (NO_CONTENT)
+     */
+    @PatchMapping("learning-path/{learningPathId}/start")
+    @EnforceAtLeastStudent
+    public ResponseEntity<Void> startLearningPathForCurrentUser(@PathVariable long learningPathId) {
+        log.debug("REST request to start learning path with id: {}", learningPathId);
+        learningPathService.startLearningPathForCurrentUser(learningPathId);
+        return ResponseEntity.noContent().build();
     }
 
     /**
@@ -324,20 +338,11 @@ public ResponseEntity<Long> getLearningPathId(@PathVariable long courseId) {
      */
     @PostMapping("courses/{courseId}/learning-path")
     @EnforceAtLeastStudentInCourse
-    public ResponseEntity<Long> generateLearningPath(@PathVariable long courseId) throws URISyntaxException {
-        log.debug("REST request to generate learning path for user in course with id: {}", courseId);
+    public ResponseEntity<LearningPathDTO> generateLearningPathForCurrentUser(@PathVariable long courseId) throws URISyntaxException {
+        log.debug("REST request to generate learning path for current user in course with id: {}", courseId);
         courseService.checkLearningPathsEnabledElseThrow(courseId);
-
-        User user = userRepository.getUser();
-        final var learningPathOptional = learningPathRepository.findByCourseIdAndUserId(courseId, user.getId());
-
-        if (learningPathOptional.isPresent()) {
-            throw new BadRequestException("Learning path already exists.");
-        }
-
-        final var course = courseRepository.findWithEagerCompetenciesAndPrerequisitesByIdElseThrow(courseId);
-        final var learningPath = learningPathService.generateLearningPathForUser(course, user);
-        return ResponseEntity.created(new URI("api/learning-path/" + learningPath.getId())).body(learningPath.getId());
+        final var learningPathDTO = learningPathService.generateLearningPathForCurrentUser(courseId);
+        return ResponseEntity.created(new URI("api/learning-path/" + learningPathDTO.id())).body(learningPathDTO);
     }
 
     /**

src/main/resources/config/liquibase/changelog/20240924125742_changelog.xml

@@ -0,0 +1,12 @@
+<?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="20240924125742" author="johannes_wt">
+        <addColumn tableName="learning_path">
+            <column name="started_by_student" defaultValueBoolean="false" type="boolean">
+                <constraints nullable="false"/>
+            </column>
+        </addColumn>
+    </changeSet>
+</databaseChangeLog>

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

@@ -23,7 +23,7 @@
     <include file="classpath:config/liquibase/changelog/20240708144500_changelog.xml" relativeToChangelogFile="false"/>
     <include file="classpath:config/liquibase/changelog/20240802091201_changelog.xml" relativeToChangelogFile="false"/>
     <include file="classpath:config/liquibase/changelog/20240804144500_changelog.xml" relativeToChangelogFile="false"/>
-
+    <include file="classpath:config/liquibase/changelog/20240924125742_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! -->
     <!-- you can use the command 'date '+%Y%m%d%H%M%S'' to get the current date and time in the correct format -->

src/main/webapp/app/course/learning-paths/pages/learning-path-student-page/learning-path-student-page.component.html

@@ -1,12 +1,12 @@
 <div class="col learning-path-student-page">
-    @if (isLearningPathIdLoading()) {
+    @if (isLearningPathLoading()) {
         <div class="row justify-content-center align-items-center h-100">
             <div class="spinner-border text-primary" role="status">
                 <span class="sr-only" jhiTranslate="loading"></span>
             </div>
         </div>
-    } @else if (learningPathId()) {
-        <jhi-learning-path-student-nav [learningPathId]="learningPathId()!" />
+    } @else if (learningPath() && learningPath()!.startedByStudent) {
+        <jhi-learning-path-student-nav [learningPathId]="learningPath()!.id" />
         <div class="learning-path-student-content">
             @if (currentLearningObject()?.type === LearningObjectType.LECTURE) {
                 <jhi-learning-path-lecture-unit [lectureUnitId]="currentLearningObject()!.id" />
@@ -27,10 +27,10 @@ <h3 class="mb-3" jhiTranslate="artemisApp.learningPath.completion.title"></h3>
                 <h3 class="mb-3" jhiTranslate="artemisApp.learningPath.generation.title"></h3>
                 <div jhiTranslate="artemisApp.learningPath.generation.description"></div>
                 <button
-                    (click)="generateLearningPath(this.courseId())"
+                    (click)="startLearningPath()"
                     type="button"
                     class="mt-4 btn btn-primary"
-                    id="generate-learning-path-button"
+                    id="start-learning-path-button"
                     jhiTranslate="artemisApp.learningPath.generation.generateButton"
                 ></button>
             </div>

src/main/webapp/app/course/learning-paths/pages/learning-path-student-page/learning-path-student-page.component.ts

@@ -1,5 +1,5 @@
 import { Component, effect, inject, signal } from '@angular/core';
-import { LearningObjectType } from 'app/entities/competency/learning-path.model';
+import { LearningObjectType, LearningPathDTO } from 'app/entities/competency/learning-path.model';
 import { map } from 'rxjs';
 import { toSignal } from '@angular/core/rxjs-interop';
 import { CommonModule } from '@angular/common';
@@ -32,45 +32,49 @@ import { ArtemisSharedModule } from 'app/shared/shared.module';
 export class LearningPathStudentPageComponent {
     protected readonly LearningObjectType = LearningObjectType;
 
-    private readonly learningApiService: LearningPathApiService = inject(LearningPathApiService);
+    private readonly learningApiService = inject(LearningPathApiService);
     private readonly learningPathNavigationService = inject(LearningPathNavigationService);
-    private readonly alertService: AlertService = inject(AlertService);
-    private readonly activatedRoute: ActivatedRoute = inject(ActivatedRoute);
+    private readonly alertService = inject(AlertService);
+    private readonly activatedRoute = inject(ActivatedRoute);
 
-    readonly isLearningPathIdLoading = signal(false);
-    readonly learningPathId = signal<number | undefined>(undefined);
+    readonly isLearningPathLoading = signal(false);
+    readonly learningPath = signal<LearningPathDTO | undefined>(undefined);
     readonly courseId = toSignal(this.activatedRoute.parent!.parent!.params.pipe(map((params) => Number(params.courseId))), { requireSync: true });
     readonly currentLearningObject = this.learningPathNavigationService.currentLearningObject;
     readonly isLearningPathNavigationLoading = this.learningPathNavigationService.isLoading;
 
     constructor() {
-        effect(async () => await this.loadLearningPathId(this.courseId()), { allowSignalWrites: true });
+        effect(() => this.loadLearningPathId(this.courseId()), { allowSignalWrites: true });
     }
 
     private async loadLearningPathId(courseId: number): Promise<void> {
         try {
-            this.isLearningPathIdLoading.set(true);
-            const learningPathId = await this.learningApiService.getLearningPathId(courseId);
-            this.learningPathId.set(learningPathId);
+            this.isLearningPathLoading.set(true);
+            const learningPath = await this.learningApiService.getLearningPathForCurrentUser(courseId);
+            this.learningPath.set(learningPath);
         } catch (error) {
             // If learning path does not exist (404) ignore the error
             if (!(error instanceof EntityNotFoundError)) {
                 this.alertService.error(error);
             }
         } finally {
-            this.isLearningPathIdLoading.set(false);
+            this.isLearningPathLoading.set(false);
         }
     }
 
-    async generateLearningPath(courseId: number): Promise<void> {
+    async startLearningPath(): Promise<void> {
         try {
-            this.isLearningPathIdLoading.set(true);
-            const learningPathId = await this.learningApiService.generateLearningPath(courseId);
-            this.learningPathId.set(learningPathId);
+            this.isLearningPathLoading.set(true);
+            if (!this.learningPath()) {
+                const learningPath = await this.learningApiService.generateLearningPathForCurrentUser(this.courseId());
+                this.learningPath.set(learningPath);
+            }
+            await this.learningApiService.startLearningPathForCurrentUser(this.learningPath()!.id);
+            this.learningPath.update((learningPath) => ({ ...learningPath!, startedByStudent: true }));
         } catch (error) {
             this.alertService.error(error);
         } finally {
-            this.isLearningPathIdLoading.set(false);
+            this.isLearningPathLoading.set(false);
         }
     }
 }

src/main/webapp/app/course/learning-paths/services/base-api-http.service.ts

@@ -122,4 +122,34 @@
     ): Promise<T> {
         return await this.request<T>(HttpMethod.Post, url, { body: body, ...options });
     }
+
+    /**
+     * Constructs a `PUT` request that interprets the body as JSON and
+     * returns a Promise of an object of type `T`.
+     *
+     * @param url The endpoint URL excluding the base server url (/api).
+     * @param body The content to include in the body of the request.
+     * @param options The HTTP options to send with the request.
+     * @protected
+     *
+     * @return An `Promise` of type `Object` (T),
+     */
+    protected async patch<T>(
+        url: string,
+        body?: any,
+        options?: {
+            headers?:
+                | HttpHeaders
+                | {
+                      [header: string]: string | string[];
+                  };
+            params?:
+                | HttpParams
+                | {
+                      [param: string]: string | number | boolean | ReadonlyArray<string | number | boolean>;
+                  };
+        },
+    ): Promise<T> {
+        return await this.request<T>(HttpMethod.Patch, url, { body: body, ...options });
+    }
 }

src/main/webapp/app/course/learning-paths/services/learning-path-api.service.ts

@@ -3,6 +3,7 @@ import {
     CompetencyGraphDTO,
     LearningObjectType,
     LearningPathCompetencyDTO,
+    LearningPathDTO,
     LearningPathNavigationDTO,
     LearningPathNavigationObjectDTO,
     LearningPathNavigationOverviewDTO,
@@ -14,8 +15,12 @@ import { BaseApiHttpService } from 'app/course/learning-paths/services/base-api-
     providedIn: 'root',
 })
 export class LearningPathApiService extends BaseApiHttpService {
-    async getLearningPathId(courseId: number): Promise<number> {
-        return await this.get<number>(`courses/${courseId}/learning-path-id`);
+    async getLearningPathForCurrentUser(courseId: number): Promise<LearningPathDTO> {
+        return await this.get<LearningPathDTO>(`courses/${courseId}/learning-path/me`);
+    }
+
+    async startLearningPathForCurrentUser(learningPathId: number): Promise<void> {
+        return await this.patch<void>(`learning-path/${learningPathId}/start`);
     }
 
     async getLearningPathNavigation(learningPathId: number): Promise<LearningPathNavigationDTO> {
@@ -35,8 +40,8 @@ export class LearningPathApiService extends BaseApiHttpService {
         return await this.get<LearningPathNavigationDTO>(`learning-path/${learningPathId}/relative-navigation`, { params: params });
     }
 
-    async generateLearningPath(courseId: number): Promise<number> {
-        return await this.post<number>(`courses/${courseId}/learning-path`);
+    async generateLearningPathForCurrentUser(courseId: number): Promise<LearningPathDTO> {
+        return await this.post<LearningPathDTO>(`courses/${courseId}/learning-path`);
     }
 
     async getLearningPathNavigationOverview(learningPathId: number): Promise<LearningPathNavigationOverviewDTO> {