fix: import errors van gabe gefixt, teacher en student abstractie weggedaan

backend/src/app.ts

@@ -5,7 +5,7 @@ import themeRoutes from './routes/themes.js';
 import learningPathRoutes from './routes/learning-paths.js';
 import learningObjectRoutes from './routes/learning-objects.js';
 
-import studentRouter from './routes/student.js';
+import studentRouter from './routes/students.js';
 import groupRouter from './routes/groups.js';
 import assignmentRouter from './routes/assignments.js';
 import submissionRouter from './routes/submissions.js';

backend/src/controllers/questions.ts

@@ -12,7 +12,7 @@ import {LearningObjectIdentifier} from "../entities/content/learning-object-iden
 import {Language} from "../entities/content/language.js";
 
 function getObjectId(req: Request, res: Response): LearningObjectIdentifier | null {
-    const { hruid, version} = req.params
+    const { hruid, version } = req.params
     const lang = req.query.lang
 
     if (!hruid || !version ) {
@@ -23,7 +23,7 @@ function getObjectId(req: Request, res: Response): LearningObjectIdentifier | nu
     return {
         hruid,
         language: lang as Language || FALLBACK_LANG,
-        version
+        version: +version
     }
 }
 

backend/src/controllers/students.ts

@@ -1,49 +1,106 @@
 import { Request, Response } from 'express';
 import {
+    createStudent,
+    deleteStudent,
+    getStudent,
     getStudentAssignments,
     getStudentClasses,
     getStudentGroups,
     getStudentSubmissions,
-    StudentService,
 } from '../services/students.js';
 import { ClassDTO } from '../interfaces/class.js';
 import { getAllAssignments } from '../services/assignments.js';
 import {
-    createUserHandler,
-    deleteUserHandler,
-    getAllUsersHandler,
     getUserHandler,
 } from './users.js';
 import { Student } from '../entities/users/student.entity.js';
+import { StudentDTO } from '../interfaces/student.js';
+import { getStudentRepository } from '../data/repositories.js';
+import { UserDTO } from '../interfaces/user.js';
 
 // TODO: accept arguments (full, ...)
 // TODO: endpoints
 export async function getAllStudentsHandler(
     req: Request,
-    res: Response
+    res: Response,
 ): Promise<void> {
-    await getAllUsersHandler<Student>(req, res, new StudentService());
+    const full = req.query.full === 'true';
+
+    const studentRepository = getStudentRepository();
+
+    const students: StudentDTO[] | string[] = full
+        ? await getAllStudents()
+        : await getAllStudents();
+
+    if (!students) {
+        res.status(404).json({ error: `Student not found.` });
+        return;
+    }
+
+    res.status(201).json(students);
 }
 
+
 export async function getStudentHandler(
     req: Request,
-    res: Response
+    res: Response,
 ): Promise<void> {
-    await getUserHandler<Student>(req, res, new StudentService());
+    const username = req.params.username;
+
+    if (!username) {
+        res.status(400).json({ error: 'Missing required field: username' });
+        return;
+    }
+
+    const user = await getStudent(username);
+
+    if (!user) {
+        res.status(404).json({
+            error: `User with username '${username}' not found.`,
+        });
+        return;
+    }
+
+    res.status(201).json(user);
 }
 
 export async function createStudentHandler(
     req: Request,
-    res: Response
-): Promise<void> {
-    await createUserHandler<Student>(req, res, new StudentService(), Student);
+    res: Response,
+) {
+    const userData = req.body as StudentDTO;
+
+    if (!userData.username || !userData.firstName || !userData.lastName) {
+        res.status(400).json({
+            error: 'Missing required fields: username, firstName, lastName',
+        });
+        return;
+    }
+
+    const newUser = await createStudent(userData);
+    res.status(201).json(newUser);
 }
 
 export async function deleteStudentHandler(
     req: Request,
-    res: Response
-): Promise<void> {
-    await deleteUserHandler<Student>(req, res, new StudentService());
+    res: Response,
+) {
+    const username = req.params.username;
+
+    if (!username) {
+        res.status(400).json({ error: 'Missing required field: username' });
+        return;
+    }
+
+    const deletedUser = await deleteStudent(username);
+    if (!deletedUser) {
+        res.status(404).json({
+            error: `User with username '${username}' not found.`,
+        });
+        return;
+    }
+
+    res.status(200).json(deletedUser);
 }
 
 export async function getStudentClassesHandler(
@@ -115,3 +172,7 @@ export async function getStudentSubmissionsHandler(
         submissions: submissions,
     });
 }
+function getAllStudents(): StudentDTO[] | string[] | PromiseLike<StudentDTO[] | string[]> {
+    throw new Error('Function not implemented.');
+}
+

backend/src/controllers/submissions.ts

@@ -21,7 +21,7 @@ export async function getSubmissionHandler(
     }
 
     let lang = languageMap[req.query.language as string] || Language.Dutch;
-    let version = req.query.version as string || '1';
+    let version = (req.query.version || 1) as number;
 
     const submission = await getSubmission(lohruid, lang, version, submissionNumber);
 
@@ -49,7 +49,7 @@ export async function deleteSubmissionHandler(req: Request, res: Response){
     const submissionNumber = +req.params.id;
 
     let lang = languageMap[req.query.language as string] || Language.Dutch;
-    let version = req.query.version as string || '1';
+    let version = (req.query.version || 1) as number;
 
     const submission = await deleteSubmission(hruid, lang, version, submissionNumber);
 

backend/src/controllers/teachers.ts

@@ -1,49 +1,96 @@
 import { Request, Response } from 'express';
-import { TeacherUserService, TeacherService } from '../services/teachers.js';
+import { createTeacher, deleteTeacher, getAllTeachers, getClassesByTeacher, getClassIdsByTeacher, getQuestionIdsByTeacher, getQuestionsByTeacher, getStudentIdsByTeacher, getStudentsByTeacher, getTeacher } from '../services/teachers.js';
 import { ClassDTO } from '../interfaces/class.js';
 import { StudentDTO } from '../interfaces/student.js';
 import { QuestionDTO, QuestionId } from '../interfaces/question.js';
-import {
-    createUserHandler,
-    deleteUserHandler,
-    getAllUsersHandler,
-    getUserHandler,
-} from './users.js';
 import { Teacher } from '../entities/users/teacher.entity.js';
+import { TeacherDTO } from '../interfaces/teacher.js';
+import { getTeacherRepository } from '../data/repositories.js';
 
 export async function getAllTeachersHandler(
     req: Request,
-    res: Response
+    res: Response,
 ): Promise<void> {
-    await getAllUsersHandler<Teacher>(req, res, new TeacherUserService());
+    const full = req.query.full === 'true';
+
+    const teacherRepository = getTeacherRepository();
+
+    const teachers: TeacherDTO[] | string[] = full
+        ? await getAllTeachers()
+        : await getAllTeachers();
+
+    if (!teachers) {
+        res.status(404).json({ error: `Teacher not found.` });
+        return;
+    }
+
+    res.status(201).json(teachers);
 }
 
+
 export async function getTeacherHandler(
     req: Request,
-    res: Response
+    res: Response,
 ): Promise<void> {
-    await getUserHandler<Teacher>(req, res, new TeacherUserService());
+    const username = req.params.username;
+
+    if (!username) {
+        res.status(400).json({ error: 'Missing required field: username' });
+        return;
+    }
+
+    const user = await getTeacher(username);
+
+    if (!user) {
+        res.status(404).json({
+            error: `User with username '${username}' not found.`,
+        });
+        return;
+    }
+
+    res.status(201).json(user);
 }
 
 export async function createTeacherHandler(
     req: Request,
-    res: Response
-): Promise<void> {
-    await createUserHandler<Teacher>(
-        req,
-        res,
-        new TeacherUserService(),
-        Teacher
-    );
+    res: Response,
+) {
+    const userData = req.body as TeacherDTO;
+
+    if (!userData.username || !userData.firstName || !userData.lastName) {
+        res.status(400).json({
+            error: 'Missing required fields: username, firstName, lastName',
+        });
+        return;
+    }
+
+    const newUser = await createTeacher(userData);
+    res.status(201).json(newUser);
 }
 
 export async function deleteTeacherHandler(
     req: Request,
-    res: Response
-): Promise<void> {
-    await deleteUserHandler<Teacher>(req, res, new TeacherUserService());
+    res: Response,
+) {
+    const username = req.params.username;
+
+    if (!username) {
+        res.status(400).json({ error: 'Missing required field: username' });
+        return;
+    }
+
+    const deletedUser = await deleteTeacher(username);
+    if (!deletedUser) {
+        res.status(404).json({
+            error: `User with username '${username}' not found.`,
+        });
+        return;
+    }
+
+    res.status(200).json(deletedUser);
 }
 
+
 export async function getTeacherClassHandler(
     req: Request,
     res: Response
@@ -57,11 +104,9 @@ export async function getTeacherClassHandler(
             return;
         }
 
-        const teacherService = new TeacherService();
-
         const classes: ClassDTO[] | string[] = full
-            ? await teacherService.getClassesByTeacher(username)
-            : await teacherService.getClassIdsByTeacher(username);
+            ? await getClassesByTeacher(username)
+            : await getClassIdsByTeacher(username);
 
         res.status(201).json(classes);
     } catch (error) {
@@ -83,11 +128,9 @@ export async function getTeacherStudentHandler(
             return;
         }
 
-        const teacherService = new TeacherService();
-
         const students: StudentDTO[] | string[] = full
-            ? await teacherService.getStudentsByTeacher(username)
-            : await teacherService.getStudentIdsByTeacher(username);
+            ? await getStudentsByTeacher(username)
+            : await getStudentIdsByTeacher(username);
 
         res.status(201).json(students);
     } catch (error) {
@@ -109,11 +152,9 @@ export async function getTeacherQuestionHandler(
             return;
         }
 
-        const teacherService = new TeacherService();
-
         const questions: QuestionDTO[] | QuestionId[] = full
-            ? await teacherService.getQuestionsByTeacher(username)
-            : await teacherService.getQuestionIdsByTeacher(username);
+            ? await getQuestionsByTeacher(username)
+            : await getQuestionIdsByTeacher(username);
 
         res.status(201).json(questions);
     } catch (error) {

backend/src/controllers/themes.ts

@@ -1,6 +1,6 @@
 import { Request, Response } from 'express';
 import { themes } from '../data/themes.js';
-import { loadTranslations } from '../util/translationHelper.js';
+import { loadTranslations } from '../util/translation-helper.js';
 
 interface Translations {
     curricula_page: {

backend/src/data/content/learning-object-repository.ts

@@ -1,6 +1,8 @@
 import { DwengoEntityRepository } from '../dwengo-entity-repository.js';
 import { LearningObject } from '../../entities/content/learning-object.entity.js';
 import { LearningObjectIdentifier } from '../../entities/content/learning-object-identifier.js';
+import { Language } from '../../entities/content/language.js';
+import { Teacher } from '../../entities/users/teacher.entity.js';
 
 export class LearningObjectRepository extends DwengoEntityRepository<LearningObject> {
     public findByIdentifier(identifier: LearningObjectIdentifier): Promise<LearningObject | null> {
@@ -30,4 +32,11 @@ export class LearningObjectRepository extends DwengoEntityRepository<LearningObj
             }
         );
     }
+
+    public findAllByTeacher(teacher: Teacher): Promise<LearningObject[]> {
+        return this.find(
+            { admins: teacher },
+            { populate: ['admins'] } // Make sure to load admin relations
+        );
+    }
 }

backend/src/data/questions/question-repository.ts

@@ -2,6 +2,7 @@ import { DwengoEntityRepository } from '../dwengo-entity-repository.js';
 import { Question } from '../../entities/questions/question.entity.js';
 import { LearningObjectIdentifier } from '../../entities/content/learning-object-identifier.js';
 import { Student } from '../../entities/users/student.entity.js';
+import { LearningObject } from '../../entities/content/learning-object.entity.js';
 
 export class QuestionRepository extends DwengoEntityRepository<Question> {
     public createQuestion(question: { loId: LearningObjectIdentifier; author: Student; content: string }): Promise<Question> {

backend/src/data/repositories.ts

@@ -56,7 +56,6 @@ function repositoryGetter<T extends AnyEntity, R extends EntityRepository<T>>(
 }
 
 /* Users */
-export const getUserRepository = repositoryGetter<User, UserRepository>(User);
 export const getStudentRepository = repositoryGetter<Student, StudentRepository>(Student);
 export const getTeacherRepository = repositoryGetter<Teacher, TeacherRepository>(Teacher);
 

backend/src/entities/assignments/assignment.entity.ts

@@ -51,5 +51,5 @@ export class Assignment {
         },
         mappedBy: 'assignment',
     })
-    groups!: Collection<Group>;
+    groups!: Group[];
 }

backend/src/entities/assignments/group.entity.ts

@@ -1,6 +1,7 @@
 import { Collection, Entity, ManyToMany, ManyToOne, PrimaryKey } from '@mikro-orm/core';
 import { Assignment } from './assignment.entity.js';
 import { Student } from '../users/student.entity.js';
+import { GroupRepository } from '../../data/assignments/group-repository.js';
 
 @Entity({
     repository: () => {

backend/src/entities/classes/class.entity.ts

@@ -8,6 +8,7 @@ import {
 import { v4 } from 'uuid';
 import { Teacher } from '../users/teacher.entity.js';
 import { Student } from '../users/student.entity.js';
+import { ClassRepository } from '../../data/classes/class-repository.js';
 
 @Entity({
     repository: () => {

backend/src/entities/content/attachment.entity.ts

@@ -1,5 +1,6 @@
 import { Entity, ManyToOne, PrimaryKey, Property } from '@mikro-orm/core';
 import { LearningObject } from './learning-object.entity.js';
+import { AttachmentRepository } from '../../data/content/attachment-repository.js';
 
 @Entity({
     repository: () => {

backend/src/entities/content/language.ts

@@ -189,5 +189,5 @@ export const languageMap: Record<string, Language> = {
     nl: Language.Dutch,
     fr: Language.French,
     en: Language.English,
-    de: Language.Germany,
+    de: Language.German,
 };

backend/src/interfaces/answer.ts

@@ -17,7 +17,7 @@ export function mapToAnswerDTO(answer: Answer): AnswerDTO {
     return {
         author: mapToUserDTO(answer.author),
         toQuestion: mapToQuestionDTO(answer.toQuestion),
-        sequenceNumber: answer.sequenceNumber,
+        sequenceNumber: answer.sequenceNumber!,
         timestamp: answer.timestamp.toISOString(),
         content: answer.content,
     };

backend/src/interfaces/question.ts

@@ -1,11 +1,13 @@
 import { Question } from '../entities/questions/question.entity.js';
 import {UserDTO} from "./user.js";
 import {LearningObjectIdentifier} from "../entities/content/learning-object-identifier.js";
+import { mapToStudentDTO, StudentDTO } from './student.js';
+import { TeacherDTO } from './teacher.js';
 
 export interface QuestionDTO {
     learningObjectIdentifier: LearningObjectIdentifier;
     sequenceNumber?: number;
-    author: UserDTO;
+    author: StudentDTO;
     timestamp?: string;
     content: string;
 }
@@ -23,7 +25,7 @@ export function mapToQuestionDTO(question: Question): QuestionDTO {
     return {
         learningObjectIdentifier,
         sequenceNumber: question.sequenceNumber!,
-        author: question.author,
+        author: mapToStudentDTO(question.author),
         timestamp: question.timestamp.toISOString(),
         content: question.content,
     };

backend/src/interfaces/student.ts

@@ -23,10 +23,11 @@ export function mapToStudentDTO(student: Student): StudentDTO {
 }
 
 export function mapToStudent(studentData: StudentDTO): Student {
-    const student = new Student();
-    student.username = studentData.username;
-    student.firstName = studentData.firstName;
-    student.lastName = studentData.lastName;
+    const student = new Student(
+        studentData.username,
+        studentData.firstName,
+        studentData.lastName,
+    );
 
     return student;
 }

backend/src/interfaces/submission.ts

@@ -8,7 +8,7 @@ import {Student} from "../entities/users/student.entity";
 export interface SubmissionDTO {
     learningObjectHruid: string,
     learningObjectLanguage: Language,
-    learningObjectVersion: string,
+    learningObjectVersion: number,
 
     submissionNumber?: number,
     submitter: StudentDTO,

backend/src/interfaces/teacher.ts

@@ -0,0 +1,33 @@
+import { Teacher } from '../entities/users/teacher.entity.js';
+
+export interface TeacherDTO {
+    id: string;
+    username: string;
+    firstName: string;
+    lastName: string;
+    endpoints?: {
+        classes: string;
+        questions: string;
+        invitations: string;
+        groups: string;
+    };
+}
+
+export function mapToTeacherDTO(teacher: Teacher): TeacherDTO {
+    return {
+        id: teacher.username,
+        username: teacher.username,
+        firstName: teacher.firstName,
+        lastName: teacher.lastName,
+    };
+}
+
+export function mapToTeacher(TeacherData: TeacherDTO): Teacher {
+    const teacher = new Teacher(
+        TeacherData.username,
+        TeacherData.firstName,
+        TeacherData.lastName,
+    );
+
+    return teacher;
+}

backend/src/routes/learning-objects.ts

@@ -1,7 +1,9 @@
 import express from 'express';
 import {
     getAllLearningObjects,
+    getAttachment,
     getLearningObject,
+    getLearningObjectHTML,
 } from '../controllers/learning-objects.js';
 
 import submissionRoutes from './submissions.js';

backend/src/services/learning-objects.ts

@@ -5,8 +5,7 @@ import {
     LearningObjectMetadata,
     LearningObjectNode,
     LearningPathResponse,
-} from '../interfaces/learning-path.js';
-import { fetchLearningPaths } from './learning-paths.js';
+} from '../interfaces/learning-content.js';
 
 function filterData(
     data: LearningObjectMetadata,
@@ -132,3 +131,7 @@ export async function getLearningObjectIdsFromPath(
 ): Promise<string[]> {
     return (await fetchLearningObjects(hruid, false, language)) as string[];
 }
+function fetchLearningPaths(arg0: string[], language: string, arg2: string): LearningPathResponse | PromiseLike<LearningPathResponse> {
+    throw new Error('Function not implemented.');
+}
+

backend/src/services/learning-objects/dwengo-api-learning-object-provider.ts

@@ -1,5 +1,5 @@
 import { DWENGO_API_BASE } from '../../config.js';
-import { fetchWithLogging } from '../../util/apiHelper.js';
+import { fetchWithLogging } from '../../util/api-helper.js';
 import {
     FilteredLearningObject,
     LearningObjectIdentifier,

backend/src/services/learning-paths/dwengo-api-learning-path-provider.ts

@@ -1,4 +1,4 @@
-import { fetchWithLogging } from '../../util/apiHelper.js';
+import { fetchWithLogging } from '../../util/api-helper.js';
 import { DWENGO_API_BASE } from '../../config.js';
 import { LearningPath, LearningPathResponse } from '../../interfaces/learning-content.js';
 import { LearningPathProvider } from './learning-path-provider.js';

backend/src/services/questions.ts

@@ -7,6 +7,7 @@ import {QuestionRepository} from "../data/questions/question-repository.js";
 import {LearningObjectIdentifier} from "../entities/content/learning-object-identifier.js";
 import {mapToUser} from "../interfaces/user.js";
 import {Student} from "../entities/users/student.entity.js";
+import { mapToStudent } from "../interfaces/student.js";
 
 export async function getAllQuestions(
     id: LearningObjectIdentifier, full: boolean
@@ -72,7 +73,7 @@ export async function getAnswersByQuestion(questionId: QuestionId, full: boolean
 export async function createQuestion(questionDTO: QuestionDTO) {
     const questionRepository = getQuestionRepository();
 
-    const author = mapToUser<Student>(questionDTO.author, new Student())
+    const author = mapToStudent(questionDTO.author);
 
     try {
         await questionRepository.createQuestion({

backend/src/services/students.ts

@@ -9,13 +9,61 @@ import { Student } from '../entities/users/student.entity.js';
 import { AssignmentDTO } from '../interfaces/assignment.js';
 import { ClassDTO, mapToClassDTO } from '../interfaces/class.js';
 import { GroupDTO, mapToGroupDTO, mapToGroupDTOId } from '../interfaces/group.js';
+import { mapToStudent, mapToStudentDTO, StudentDTO } from '../interfaces/student.js';
 import { mapToSubmissionDTO, SubmissionDTO } from '../interfaces/submission.js';
 import { getAllAssignments } from './assignments.js';
 import { UserService } from './users.js';
 
-export class StudentService extends UserService<Student> {
-    constructor() {
-        super(getStudentRepository());
+
+export async function getAllStudents(): Promise<StudentDTO[]> {
+    const studentRepository = getStudentRepository();
+    const users = await studentRepository.findAll();
+    return users.map(mapToStudentDTO);
+}
+
+export async function getAllStudentIds(): Promise<string[]> {
+    const users = await getAllStudents();
+    return users.map((user) => {
+        return user.username;
+    });
+}
+
+export async function getStudent(username: string): Promise<StudentDTO | null> {
+    const studentRepository = getStudentRepository();
+    const user = await studentRepository.findByUsername(username);
+    return user ? mapToStudentDTO(user) : null;
+}
+
+export async function createStudent(userData: StudentDTO): Promise<StudentDTO | null> {
+    const studentRepository = getStudentRepository();
+
+    try {
+        const newStudent = studentRepository.create(mapToStudent(userData));
+        await studentRepository.save(newStudent);
+    
+        return mapToStudentDTO(newStudent);
+    } catch(e) {
+        console.log(e);
+        return null;
+    }
+}
+
+export async function deleteStudent(username: string): Promise<StudentDTO | null> {
+    const studentRepository = getStudentRepository();
+
+    const user = await studentRepository.findByUsername(username);
+
+    if (!user) {
+        return null;
+    }
+
+    try {
+        await studentRepository.deleteByUsername(username);
+    
+        return mapToStudentDTO(user);
+    } catch(e) {
+        console.log(e);
+        return null;
     }
 }
 

backend/src/services/submissions.ts

@@ -6,7 +6,7 @@ import {mapToSubmission, mapToSubmissionDTO, SubmissionDTO} from "../interfaces/
 export async function getSubmission(
     learningObjectHruid: string,
     language: Language,
-    version: string,
+    version: number,
     submissionNumber: number,
 ): Promise<SubmissionDTO | null> {
     const loId = new LearningObjectIdentifier(learningObjectHruid, language, version);
@@ -38,7 +38,7 @@ export async function createSubmission(submissionDTO: SubmissionDTO) {
 export async function deleteSubmission(
     learningObjectHruid: string,
     language: Language,
-    version: string,
+    version: number,
     submissionNumber: number
 ) {
     const submissionRepository = getSubmissionRepository();

backend/src/services/teachers.ts

@@ -17,43 +17,85 @@ import {
 } from '../interfaces/question.js';
 import { UserService } from './users.js';
 import { mapToUser } from '../interfaces/user.js';
+import { mapToTeacher, mapToTeacherDTO, TeacherDTO } from '../interfaces/teacher.js';
 
-export class TeacherUserService extends UserService<Teacher> {
-    constructor() {
-        super(getTeacherRepository());
+export async function getAllTeachers(): Promise<TeacherDTO[]> {
+    const teacherRepository = getTeacherRepository();
+    const users = await teacherRepository.findAll();
+    return users.map(mapToTeacherDTO);
+}
+
+export async function getAllTeacherIds(): Promise<string[]> {
+    const users = await getAllTeachers();
+    return users.map((user) => {
+        return user.username;
+    });
+}
+
+export async function getTeacher(username: string): Promise<TeacherDTO | null> {
+    const teacherRepository = getTeacherRepository();
+    const user = await teacherRepository.findByUsername(username);
+    return user ? mapToTeacherDTO(user) : null;
+}
+
+export async function createTeacher(userData: TeacherDTO): Promise<TeacherDTO | null> {
+    const teacherRepository = getTeacherRepository();
+
+    try {
+        const newTeacher = teacherRepository.create(mapToTeacher(userData));
+        await teacherRepository.save(newTeacher);
+    
+        return mapToTeacherDTO(newTeacher);
+    } catch(e) {
+        console.log(e);
+        return null;
     }
 }
 
-export class TeacherService {
-    protected teacherService = new TeacherUserService();
-    protected teacherRepository = getTeacherRepository();
-    protected classRepository = getClassRepository();
-    protected learningObjectRepository = getLearningObjectRepository();
-    protected questionRepository = getQuestionRepository();
+export async function deleteTeacher(username: string): Promise<TeacherDTO | null> {
+    const teacherRepository = getTeacherRepository();
 
-    async fetchClassesByTeacher(username: string): Promise<ClassDTO[]> {
-        const teacher = await this.teacherRepository.findByUsername(username);
+    const user = await teacherRepository.findByUsername(username);
+
+    if (!user) {
+        return null;
+    }
+
+    try {
+        await teacherRepository.deleteByUsername(username);
+    
+        return mapToTeacherDTO(user);
+    } catch(e) {
+        console.log(e);
+        return null;
+    }
+}
+
+export async function fetchClassesByTeacher(username: string): Promise<ClassDTO[]> {
+    const teacherRepository = getTeacherRepository();
+    const teacher = await teacherRepository.findByUsername(username);
     if (!teacher) {
         return [];
     }
 
-        const classes = await this.classRepository.findByTeacher(teacher);
+    const classRepository = getClassRepository();
+    const classes = await classRepository.findByTeacher(teacher);
     return classes.map(mapToClassDTO);
-    }
+}
 
-    async getClassesByTeacher(username: string): Promise<ClassDTO[]> {
-        return await this.fetchClassesByTeacher(username);
-    }
+export async function getClassesByTeacher(username: string): Promise<ClassDTO[]> {
+    return await fetchClassesByTeacher(username);
+}
 
-    async getClassIdsByTeacher(username: string): Promise<string[]> {
-        const classes = await this.fetchClassesByTeacher(username);
+export async function getClassIdsByTeacher(username: string): Promise<string[]> {
+    const classes = await fetchClassesByTeacher(username);
     return classes.map((cls) => {
         return cls.id;
     });
-    }
+}
 
-    async fetchStudentsByTeacher(username: string) {
-        const classes = await this.getClassIdsByTeacher(username);
+export async function fetchStudentsByTeacher(username: string) {
+    const classes = await getClassIdsByTeacher(username);
 
     return (
         await Promise.all(
@@ -62,48 +104,46 @@ export class TeacherService {
             })
         )
     ).flat();
-    }
+}
 
-    async getStudentsByTeacher(username: string): Promise<StudentDTO[]> {
-        return await this.fetchStudentsByTeacher(username);
-    }
+export async function getStudentsByTeacher(username: string): Promise<StudentDTO[]> {
+    return await fetchStudentsByTeacher(username);
+}
 
-    async getStudentIdsByTeacher(username: string): Promise<string[]> {
-        const students = await this.fetchStudentsByTeacher(username);
+export async function getStudentIdsByTeacher(username: string): Promise<string[]> {
+    const students = await fetchStudentsByTeacher(username);
     return students.map((student) => {
         return student.username;
     });
-    }
+}
 
-    async fetchTeacherQuestions(username: string): Promise<QuestionDTO[]> {
-        const teacherDTO =
-            await this.teacherService.getUserByUsername(username);
-        if (!teacherDTO) {
+export async function fetchTeacherQuestions(username: string): Promise<QuestionDTO[]> {
+    const teacherRepository = getTeacherRepository();
+    const teacher = await teacherRepository.findByUsername(username);
+    if (!teacher) {
         throw new Error(`Teacher with username '${username}' not found.`);
     }
 
-        const teacher = mapToUser<Teacher>(teacherDTO, new Teacher());
-
     // Find all learning objects that this teacher manages
-        const learningObjects =
-            await this.learningObjectRepository.findAllByTeacher(teacher);
+    const learningObjectRepository = getLearningObjectRepository();
+    const learningObjects = await learningObjectRepository.findAllByTeacher(teacher);
 
     // Fetch all questions related to these learning objects
+    const questionRepository = getQuestionRepository();
     const questions =
-            await this.questionRepository.findAllByLearningObjects(
+        await questionRepository.findAllByLearningObjects(
             learningObjects
         );
 
     return questions.map(mapToQuestionDTO);
-    }
+}
 
-    async getQuestionsByTeacher(username: string): Promise<QuestionDTO[]> {
-        return await this.fetchTeacherQuestions(username);
-    }
+export async function getQuestionsByTeacher(username: string): Promise<QuestionDTO[]> {
+    return await fetchTeacherQuestions(username);
+}
 
-    async getQuestionIdsByTeacher(username: string): Promise<QuestionId[]> {
-        const questions = await this.fetchTeacherQuestions(username);
+export async function getQuestionIdsByTeacher(username: string): Promise<QuestionId[]> {
+    const questions = await fetchTeacherQuestions(username);
 
     return questions.map(mapToQuestionId);
-    }
 }

backend/tests/data/assignments/submissions.test.ts

@@ -32,7 +32,7 @@ describe('SubmissionRepository', () => {
     });
 
     it('should find the requested submission', async () => {
-        const id = new LearningObjectIdentifier('id03', Language.English, '1');
+        const id = new LearningObjectIdentifier('id03', Language.English, 1);
         const submission = await submissionRepository.findSubmissionByLearningObjectAndSubmissionNumber(id, 1);
 
         expect(submission).toBeTruthy();
@@ -40,7 +40,7 @@ describe('SubmissionRepository', () => {
     });
 
     it('should find the most recent submission for a student', async () => {
-        const id = new LearningObjectIdentifier('id02', Language.English, '1');
+        const id = new LearningObjectIdentifier('id02', Language.English, 1);
         const student = await studentRepository.findByUsername('Noordkaap');
         const submission = await submissionRepository.findMostRecentSubmissionForStudent(id, student!);
 
@@ -49,7 +49,7 @@ describe('SubmissionRepository', () => {
     });
 
     it('should find the most recent submission for a group', async () => {
-        const id = new LearningObjectIdentifier('id03', Language.English, '1');
+        const id = new LearningObjectIdentifier('id03', Language.English, 1);
         const class_ = await classRepository.findById('id01');
         const assignment = await assignmentRepository.findByClassAndId(class_!, 1);
         const group = await groupRepository.findByAssignmentAndGroupNumber(assignment!, 1);
@@ -60,7 +60,7 @@ describe('SubmissionRepository', () => {
     });
 
     it('should not find a deleted submission', async () => {
-        const id = new LearningObjectIdentifier('id01', Language.English, '1');
+        const id = new LearningObjectIdentifier('id01', Language.English, 1);
         await submissionRepository.deleteSubmissionByLearningObjectAndSubmissionNumber(id, 1);
 
         const submission = await submissionRepository.findSubmissionByLearningObjectAndSubmissionNumber(id, 1);

backend/tests/data/content/attachments.test.ts

@@ -17,11 +17,11 @@ describe('AttachmentRepository', () => {
     });
 
     it('should return the requested attachment', async () => {
-        const id = new LearningObjectIdentifier('id02', Language.English, '1');
+        const id = new LearningObjectIdentifier('id02', Language.English, 1);
         const learningObject = await learningObjectRepository.findByIdentifier(id);
 
         const attachment = await attachmentRepository.findByMostRecentVersionOfLearningObjectAndName(
-            learningObject!,
+            learningObject!.hruid,
             Language.English,
             'attachment01'
         );

backend/tests/data/content/learning-objects.test.ts

@@ -13,8 +13,8 @@ describe('LearningObjectRepository', () => {
         learningObjectRepository = getLearningObjectRepository();
     });
 
-    const id01 = new LearningObjectIdentifier('id01', Language.English, '1');
-    const id02 = new LearningObjectIdentifier('test_id', Language.English, '1');
+    const id01 = new LearningObjectIdentifier('id01', Language.English, 1);
+    const id02 = new LearningObjectIdentifier('test_id', Language.English, 1);
 
     it('should return the learning object that matches identifier 1', async () => {
         const learningObject = await learningObjectRepository.findByIdentifier(id01);

backend/tests/data/questions/answers.test.ts

@@ -20,7 +20,7 @@ describe('AnswerRepository', () => {
     });
 
     it('should find all answers to a question', async () => {
-        const id = new LearningObjectIdentifier('id05', Language.English, '1');
+        const id = new LearningObjectIdentifier('id05', Language.English, 1);
         const questions = await questionRepository.findAllQuestionsAboutLearningObject(id);
 
         const question = questions.filter((it) => it.sequenceNumber == 2)[0];
@@ -35,7 +35,7 @@ describe('AnswerRepository', () => {
 
     it('should create an answer to a question', async () => {
         const teacher = await teacherRepository.findByUsername('FooFighters');
-        const id = new LearningObjectIdentifier('id05', Language.English, '1');
+        const id = new LearningObjectIdentifier('id05', Language.English, 1);
         const questions = await questionRepository.findAllQuestionsAboutLearningObject(id);
 
         const question = questions[0];
@@ -54,7 +54,7 @@ describe('AnswerRepository', () => {
     });
 
     it('should not find a removed answer', async () => {
-        const id = new LearningObjectIdentifier('id04', Language.English, '1');
+        const id = new LearningObjectIdentifier('id04', Language.English, 1);
         const questions = await questionRepository.findAllQuestionsAboutLearningObject(id);
 
         await answerRepository.removeAnswerByQuestionAndSequenceNumber(questions[0], 1);

backend/tests/data/questions/questions.test.ts

@@ -20,7 +20,7 @@ describe('QuestionRepository', () => {
     });
 
     it('should return all questions part of the given learning object', async () => {
-        const id = new LearningObjectIdentifier('id05', Language.English, '1');
+        const id = new LearningObjectIdentifier('id05', Language.English, 1);
         const questions = await questionRepository.findAllQuestionsAboutLearningObject(id);
 
         expect(questions).toBeTruthy();
@@ -28,7 +28,7 @@ describe('QuestionRepository', () => {
     });
 
     it('should create new question', async () => {
-        const id = new LearningObjectIdentifier('id03', Language.English, '1');
+        const id = new LearningObjectIdentifier('id03', Language.English, 1);
         const student = await studentRepository.findByUsername('Noordkaap');
         await questionRepository.createQuestion({
             loId: id,
@@ -42,7 +42,7 @@ describe('QuestionRepository', () => {
     });
 
     it('should not find removed question', async () => {
-        const id = new LearningObjectIdentifier('id04', Language.English, '1');
+        const id = new LearningObjectIdentifier('id04', Language.English, 1);
         await questionRepository.removeQuestionByLearningObjectAndSequenceNumber(id, 1);
 
         const question = await questionRepository.findAllQuestionsAboutLearningObject(id);

backend/tests/test_assets/assignments/submission.testdata.ts

@@ -12,7 +12,7 @@ export function makeTestSubmissions(
     const submission01 = em.create(Submission, {
         learningObjectHruid: 'id03',
         learningObjectLanguage: Language.English,
-        learningObjectVersion: '1',
+        learningObjectVersion: 1,
         submissionNumber: 1,
         submitter: students[0],
         submissionTime: new Date(2025, 2, 20),
@@ -23,7 +23,7 @@ export function makeTestSubmissions(
     const submission02 = em.create(Submission, {
         learningObjectHruid: 'id03',
         learningObjectLanguage: Language.English,
-        learningObjectVersion: '1',
+        learningObjectVersion: 1,
         submissionNumber: 2,
         submitter: students[0],
         submissionTime: new Date(2025, 2, 25),
@@ -34,7 +34,7 @@ export function makeTestSubmissions(
     const submission03 = em.create(Submission, {
         learningObjectHruid: 'id02',
         learningObjectLanguage: Language.English,
-        learningObjectVersion: '1',
+        learningObjectVersion: 1,
         submissionNumber: 1,
         submitter: students[0],
         submissionTime: new Date(2025, 2, 20),
@@ -44,7 +44,7 @@ export function makeTestSubmissions(
     const submission04 = em.create(Submission, {
         learningObjectHruid: 'id02',
         learningObjectLanguage: Language.English,
-        learningObjectVersion: '1',
+        learningObjectVersion: 1,
         submissionNumber: 2,
         submitter: students[0],
         submissionTime: new Date(2025, 2, 25),
@@ -54,7 +54,7 @@ export function makeTestSubmissions(
     const submission05 = em.create(Submission, {
         learningObjectHruid: 'id01',
         learningObjectLanguage: Language.English,
-        learningObjectVersion: '1',
+        learningObjectVersion: 1,
         submissionNumber: 1,
         submitter: students[1],
         submissionTime: new Date(2025, 2, 20),

backend/tests/test_assets/content/learning-paths.testdata.ts

@@ -77,7 +77,7 @@ export function makeTestLearningPaths(em: EntityManager<IDatabaseDriver<Connecti
         admins: [],
         title: 'repertoire Tool',
         description: 'all about Tool',
-        image: '',
+        image: null,
         nodes: nodes01,
     });
 
@@ -92,7 +92,7 @@ export function makeTestLearningPaths(em: EntityManager<IDatabaseDriver<Connecti
         admins: [],
         title: 'repertoire Dire Straits',
         description: 'all about Dire Straits',
-        image: '',
+        image: null,
         nodes: nodes02,
     });
 

backend/tests/test_assets/questions/questions.testdata.ts

@@ -6,7 +6,7 @@ import { Student } from '../../../src/entities/users/student.entity';
 export function makeTestQuestions(em: EntityManager<IDatabaseDriver<Connection>>, students: Array<Student>): Array<Question> {
     const question01 = em.create(Question, {
         learningObjectLanguage: Language.English,
-        learningObjectVersion: '1',
+        learningObjectVersion: 1,
         learningObjectHruid: 'id05',
         sequenceNumber: 1,
         author: students[0],
@@ -16,7 +16,7 @@ export function makeTestQuestions(em: EntityManager<IDatabaseDriver<Connection>>
 
     const question02 = em.create(Question, {
         learningObjectLanguage: Language.English,
-        learningObjectVersion: '1',
+        learningObjectVersion: 1,
         learningObjectHruid: 'id05',
         sequenceNumber: 2,
         author: students[2],
@@ -26,7 +26,7 @@ export function makeTestQuestions(em: EntityManager<IDatabaseDriver<Connection>>
 
     const question03 = em.create(Question, {
         learningObjectLanguage: Language.English,
-        learningObjectVersion: '1',
+        learningObjectVersion: 1,
         learningObjectHruid: 'id04',
         sequenceNumber: 1,
         author: students[0],
@@ -36,7 +36,7 @@ export function makeTestQuestions(em: EntityManager<IDatabaseDriver<Connection>>
 
     const question04 = em.create(Question, {
         learningObjectLanguage: Language.English,
-        learningObjectVersion: '1',
+        learningObjectVersion: 1,
         learningObjectHruid: 'id01',
         sequenceNumber: 1,
         author: students[1],