fetchRelated<R extends DatumEntityInterface> method

Future<List<R>> fetchRelated<R extends DatumEntityInterface>(T parent, String relationName, { DataSource source = DataSource.local, })

Fetches related entities for a given parent entity (the internals behind the deprecated DatumManager.fetchRelated).

Implementation

Future<List<R>> fetchRelated<R extends DatumEntityInterface>(
  T parent,
  String relationName, {
  DataSource source = DataSource.local,
}) async {
  if (parent is RelationalDatumEntity) {
    final relation = parent.relations[relationName];
    if (relation == null) {
      throw ArgumentError(
        'Relation "$relationName" is not defined on entity type ${parent.runtimeType}.',
      );
    }
  } else {
    throw ArgumentError(
      'The parent entity must be a RelationalDatumEntity to fetch relations.',
    );
  }

  final relatedManager = Datum.manager<R>();

  switch (source) {
    case DataSource.local:
      return manager.localAdapter.fetchRelated(
        parent,
        relationName,
        relatedManager.localAdapter,
      );
    case DataSource.remote:
      return manager.remoteAdapter.fetchRelated(
        parent,
        relationName,
        relatedManager.remoteAdapter,
      );
  }
}