Skip to main content

Documentation Index

Fetch the complete documentation index at: https://mintlify.com/Distribuidos-Org/ms-alumnos/llms.txt

Use this file to discover all available pages before exploring further.

ms-alumnos ships with a dedicated seed module that gives developers an instant, repeatable starting point. Sending a single NATS message truncates the alumnos table and inserts 100 realistic student records so you can explore API behaviour, run manual tests, or hand-off a demo environment without crafting fixtures by hand.

​
How it works

The seed feature is composed of three layers that work together: SeedController — registered as a NestJS microservice controller, it listens for the { cmd: 'seed_alumnos' } message pattern and delegates immediately to SeedService: 
@Controller('seed')
export class SeedController {
  constructor(private readonly seedService: SeedService) {}

  @MessagePattern({ cmd: 'seed_alumnos' })
  runSeed() {
    return this.seedService.runSeed();
  }
}
SeedService — contains the actual database logic. It first issues a raw TRUNCATE query to wipe existing rows and reset the sequence, then uses the TypeORM repository to bulk-create and save all 100 records from the static data array: 
@Injectable()
export class SeedService {
  constructor(
    @InjectRepository(Alumno)
    private readonly alumnoRepository: Repository<Alumno>,
  ) {}

  async runSeed() {
    await this.alumnoRepository.query(`
      TRUNCATE TABLE "alumnos" RESTART IDENTITY CASCADE
    `);

    const alumnos = seedAlumnosData.map((alumno) => {
      return this.alumnoRepository.create(alumno);
    });

    await this.alumnoRepository.save(alumnos);

    return { message: 'Seed ejecutado correctamente', count: alumnos.length };
  }
}
seedAlumnosData (src/seed/data/sees.data.ts) — a static array of 100 objects that conform to the SeedAlumno interface. Each object carries every field required by the Alumno entity so that TypeORM can persist them without additional transformation.

​
Running the seed

Trigger the seed by publishing a NATS request to the seed_alumnos subject. Any NATS client works; the example below uses the official nats npm package: 
import { connect, JSONCodec } from 'nats';

const nc = await connect({ servers: 'nats://localhost:4222' });
const jc = JSONCodec();

const res = await nc.request('seed_alumnos', jc.encode({}), { timeout: 15000 });
console.log(jc.decode(res.data));
// { message: 'Seed ejecutado correctamente', count: 100 }

await nc.drain();
A successful run returns the object { message: 'Seed ejecutado correctamente', count: 100 }. The count field always reflects the number of rows actually saved, which makes it easy to assert correctness in automated scripts.
Run the seed right after starting a fresh database or after running end-to-end tests to restore a known, consistent state before the next test pass.

​
Sample data overview

The 100 seed records are spread across four Peruvian universities and a variety of faculties and degree levels, giving a representative cross-section of student data:
FieldRange / Values
dni10000001 – 10000100 (sequential)
edad24 – 35
universidadUNMSM, UNI, PUCP, USMP
gradoBachiller, Licenciado, Magíster, Doctor
egresadoLocaltrue or false
University coverage across the dataset:
  • UNMSM — largest group, primarily from FISI (Ing. Sistemas, Ing. Software) and faculties of Medicina, Psicología, Ciencias, and Letras.
  • UNI — engineering-focused: Ing. Civil, Mecánica, Electrónica, Mecatrónica, Ambiental, Química, Eléctrica, and Industrial.
  • PUCP — diverse: Derecho, Economía, Psicología, Ciencias Sociales, Arquitectura, Arte, and Ciencias.
  • USMP — Medicina, Derecho, Contabilidad, Administración, Comunicación, and Psicología.
Every record uses @example.com email addresses and the placeholder password contrasena. Do not use these records in a production environment.

​
Reset behavior

The seed service executes the following SQL before inserting new rows: 
TRUNCATE TABLE "alumnos" RESTART IDENTITY CASCADE
RESTART IDENTITY resets the PostgreSQL auto-increment sequence back to 1, so the primary keys assigned to the new seed records always start from a predictable value. CASCADE ensures that any foreign-key relationships that reference the alumnos table are also cleaned up automatically.
Running the seed permanently deletes all existing records in the alumnos table — including any data you created manually or through API calls. There is no undo. Do not run this against a shared or production database.

Build docs developers (and LLMs) love

Get started for freeTalk to us