104. Services

Services

Providers | NestJS - A progressive Node.js framework
Services are a specific type of provider in Nest.js that encapsulate reusable business logic(i.e CRUD, Billing…).
- They are typically used to abstract complex operations and promote code reuse across different parts of the application.
- Services help maintain a modular architecture and can be easily injected into controllers or other services as a singleton.

nest g s service-name

@Injectable()
export class CatsService {
  private readonly cats: Cat[] = [];

  create(cat: Cat) {
    this.cats.push(cat);
  }

  findAll(): Cat[] {
    return this.cats;
  }
}

@Controller('cats')
export class CatsController {
  constructor(private catsService: CatsService) {}

  @Post()
  async create(@Body() createCatDto: CreateCatDto) {
    this.catsService.create(createCatDto);
  }

  @Get()
  async findAll(): Promise<Cat[]> {
    return this.catsService.findAll();
  }
}

Finally you need to add your service to respective module

@Module({
  controllers: [CatsController],
  providers: [CatsService],
})
export class AppModule {}

There are different type of providers in addition to services, to learn more check Providers

104. Services

Services​

Services