ArrowField.fromJson constructor

Implementation

factory ArrowField.fromJson(Map<String, Object?> json) {
  try {
    final name = json['name'];
    final dtype = json['dtype'] ?? json['type'];
    if (name is! String || dtype is! Map) {
      throw const FormatException('Invalid Arrow field');
    }
    final nullable = json['nullable'];
    if (nullable != null || json.containsKey('nullable')) {
      if (nullable is! bool) {
        throw const FormatException('field.nullable must be a boolean');
      }
    }
    return ArrowField(
      name,
      ArrowDataType.fromJson(_stringObjectMap(dtype, 'field.dtype')),
      nullable: nullable as bool? ?? true,
      allowEmptyName: true,
      metadata: _metadataFromJson(
        json['metadata'],
        'field.metadata',
        present: json.containsKey('metadata'),
      ),
    );
  } on FormatException {
    rethrow;
  } on ArgumentError catch (error) {
    throw FormatException('Invalid Arrow field: $error');
  } on TypeError catch (error) {
    throw FormatException('Invalid Arrow field shape: $error');
  }
}