clean-nestjs-structure.ts

// modules/example/interfaces/listing.interface.ts
export interface ListingInterface {
  names: string[];
}

// modules/example/dtos/listing.dto.ts
export class ListingPayloadDto implements ListingInterface {
  // class-validator validations
  // @nestjs/swagger decorators
  readonly names!: string[];
}

// modules/example/services/example.service.ts
@Injectable()
export class ExampleService {
  async list(data: ListingInterface): Promise<string> {
    return data.names.join(`\n`);
  }
}

// modules/example/controllers/example.controller.ts
@Controller('example')
export class ExampleController {
  constructor(private readonly exampleService: ExampleService) {}

  @Post()
  async list(@Body() payload: ListingPayloadDto): Promise<string> {
    return await this.exampleService.list(payload);
  }
}