Datacat.fromJsonMapString constructor

Datacat.fromJsonMapString(String jsonString)

Creates nested Datacats from a JSON string representing a map where each key maps to a list of objects.

Implementation

factory Datacat.fromJsonMapString(String jsonString) {
  final decoded = json.decode(jsonString);
  if (decoded is! Map) {
    throw ArgumentError(
        'JSON input must be a map with keys mapping to lists.');
  }
  final result = <String, Datacat>{};
  decoded.forEach((key, value) {
    if (value is List) {
      result[key.toString()] = Datacat.fromJsonString(json.encode(value));
    } else {
      throw ArgumentError('Value for key "$key" must be a list.');
    }
  });
  // Return a Datacat whose columns are the keys (names of nested tables)
  // and no rows. Adjust as needed.
  return Datacat(columns: result.keys.toList(), rows: []);
}