1. @httpGet
Future<Response> getObject(String id)

Source 

@httpGet
Future<Response> getObject(@HTTPPath("id") String id) async {
  var primaryKey = _query.entity.primaryKey;
  _query.where[primaryKey] = whereEqualTo(
      _parseValueForProperty(id, _query.entity.properties[primaryKey]));

  _query = await willFindObjectWithQuery(_query);

  var result = await _query?.fetchOne();

  if (result == null) {
    return didNotFindObject();
  } else {
    return didFindObject(result);
  }
}