feat: teacher get, post en delete route

backend/src/services/teachers.ts

@@ -0,0 +1,38 @@
+import {getTeacherRepository} from "../data/repositories.js";
+import {mapToTeacher, mapToTeacherDTO, TeacherDTO} from "../interfaces/teacher.js";
+import { Teacher } from "../entities/users/teacher.entity";
+
+
+export async function fetchAllTeachers(): Promise<TeacherDTO[]> {
+    const teacherRepository = getTeacherRepository();
+    const teachers = await teacherRepository.find({});
+
+    return teachers.map(mapToTeacherDTO);
+}
+
+export async function createTeacher(teacherData: TeacherDTO): Promise<Teacher> {
+    const teacherRepository = getTeacherRepository();
+    const newTeacher = mapToTeacher(teacherData);
+
+    await teacherRepository.addTeacher(newTeacher);
+    return newTeacher;
+}
+
+export async function fetchTeacherByUsername(username: string): Promise<TeacherDTO | null> {
+    const teacherRepository = getTeacherRepository();
+    const teacher = await teacherRepository.findByUsername(username);
+
+    return teacher ? mapToTeacherDTO(teacher) : null;
+}
+
+export async function deleteTeacher(username: string): Promise<TeacherDTO | null> {
+    const teacherRepository = getTeacherRepository();
+    const teacher = await teacherRepository.findByUsername(username);
+
+    if (!teacher)
+        return null;
+
+    await teacherRepository.deleteByUsername(username);
+    return teacher;
+}
+