add folder operation and use createQueryRunner

src/alumno/dto/create-student.dto.ts

@@ -1,5 +1,5 @@
-import { Type } from 'class-transformer';
-import { IsDate, IsNotEmpty, IsNumber, IsString } from 'class-validator';
+
+import { IsEmail, IsNotEmpty, IsNumber, IsString } from 'class-validator';
 
 export class CreateStudentDto {
   @IsNotEmpty()
@@ -17,6 +17,7 @@ export class CreateStudentDto {
   @IsNumber()
   id_carrera: number;
 
+  @IsEmail()
   @IsString()
   correo: string;
 }

src/alumno/entities/student.entity.ts

@@ -26,7 +26,7 @@ export class Student {
     scale: 2,
     default: 0.0,
   })
-  credito: string;
+  credito: number;
 
   @Column({
     name: 'fecha_actualizacion_credito',

src/alumno/student.controller.ts

@@ -27,17 +27,7 @@ export class StudentController {
   }
 
   @Get(':id')
-  findOne(@Param('id') id: string) {
+  findOne(@Param('id') id: number) {
     return this.studentService.findOne(+id);
   }
-
-  @Patch(':id')
-  update(@Param('id') id: string, @Body() updateStudentDto: UpdateStudentDto) {
-    return this.studentService.update(+id, updateStudentDto);
-  }
-
-  @Delete(':id')
-  remove(@Param('id') id: string) {
-    return this.studentService.remove(+id);
-  }
 }

src/alumno/student.service.ts

@@ -2,7 +2,7 @@ import { Injectable, NotFoundException } from '@nestjs/common';
 import { CreateStudentDto } from './dto/create-student.dto';
 import { UpdateStudentDto } from './dto/update-student.dto';
 import { Student } from './entities/student.entity';
-import { Repository } from 'typeorm';
+import { EntityManager, Repository } from 'typeorm';
 import { InjectRepository } from '@nestjs/typeorm';
 
 @Injectable()
@@ -31,11 +31,22 @@ export class StudentService {
     return student;
   }
 
-  update(id: number, updateStudentDto: UpdateStudentDto) {
-    return `This action updates a #${id} student`;
+  async GetCredit(id_cuenta: number): Promise<Student['credito']> {
+    const student = await this.findOne(id_cuenta);
+    return student.credito;
   }
 
-  remove(id: number) {
-    return `This action removes a #${id} student`;
+  async UpdateCredit(
+    id_cuenta: number,
+    credit: number,
+    manager: EntityManager,
+  ) {
+    const repo = manager.getRepository(Student);
+    return await repo
+      .createQueryBuilder()
+      .update()
+      .set({ credito: () => `credito - ${credit}` })
+      .where({ id_cuenta })
+      .execute();
   }
 }