Module Provider Injection

Module provider injection is a NestJS feature where module classes can inject providers via constructor (e.g., for configuration purposes):

@Module({ controllers: [CatsController], providers: [CatsService] })
export class CatsModule {
  constructor(private catsService: CatsService) {}
}

Module classes themselves cannot be injected as providers into other classes due to circular dependency restrictions. This injection is primarily used for accessing configuration within the module that owns the provider.