added folder student and create new Ep Login

src/user/user.service.ts

@@ -1,9 +1,17 @@
-import { Injectable } from '@nestjs/common';
+import { Injectable, Logger, NotFoundException, UnauthorizedException } from '@nestjs/common';
 import { CreateUserDto } from './dto/create-user.dto';
 import { UpdateUserDto } from './dto/update-user.dto';
+import { InjectRepository } from '@nestjs/typeorm';
+import { User } from './entities/user.entity';
+import { Repository } from 'typeorm';
 
 @Injectable()
 export class UserService {
+  constructor(
+    @InjectRepository(User)
+    private userRepository: Repository<User>,
+  ) { }
+
   create(createUserDto: CreateUserDto) {
     return 'This action adds a new user';
   }
@@ -12,8 +20,19 @@ export class UserService {
     return `This action returns all user`;
   }
 
-  findOne(id: number) {
-    return `This action returns a #${id} user`;
+  async findOneByName(nombre: string): Promise<User> {
+
+    const user = await this.userRepository.findOne({
+      where: { nombre }
+    })
+
+    if (!user) {
+      throw new NotFoundException(
+        `El usuario ${nombre} no fue encontrado`,
+      );
+    }
+
+    return user;
   }
 
   update(id: number, updateUserDto: UpdateUserDto) {
@@ -23,4 +42,16 @@ export class UserService {
   remove(id: number) {
     return `This action removes a #${id} user`;
   }
+
+  async Login(data: CreateUserDto) {
+    const { username } = data
+
+    if (!username) {
+      throw new UnauthorizedException('Credenciales inválidas.');
+    }
+
+    const user = await this.findOneByName(username)
+    return user
+  }
+
 }