feat: add, delete student route met user logic + .js in files

backend/src/services/users.ts

@@ -0,0 +1,39 @@
+import { UserRepository } from "../data/users/user-repository.js";
+import { UserDTO, mapToUser, mapToUserDTO } from "../interfaces/user.js";
+import {User} from "../entities/users/user.entity.js";
+
+export class UserService<T extends User> {
+    protected repository: UserRepository<T>;
+
+    constructor(repository: UserRepository<T>) {
+        this.repository = repository;
+    }
+
+    async getAllUsers(): Promise<UserDTO[]> {
+        const users = await this.repository.findAll();
+        return users.map(mapToUserDTO);
+    }
+
+    async getAllUserIds(): Promise<string[]> {
+        const users = await this.getAllUsers();
+        return users.map((user) => user.username);
+    }
+
+    async getUserByUsername(username: string): Promise<UserDTO | null> {
+        const user = await this.repository.findByUsername(username)
+        return user ? mapToUserDTO(user) : null;
+    }
+
+    async createUser(userData: UserDTO, UserClass: new () => T): Promise<T> {
+        const newUser = mapToUser(userData, new UserClass());
+        await this.repository.save(newUser);
+        return newUser;
+    }
+
+    async deleteUser(username: string): Promise<UserDTO | null> {
+        const user = await this.getUserByUsername(username);
+        if (!user) return null;
+        await this.repository.deleteByUsername(username)
+        return mapToUserDTO(user);
+    }
+}