transformer<T> method

@override Future<Response<T>> transformer<T>(Response<T> response)

Implementation

@override
Future<Response<T>> transformer<T>(Response<T> response) async {
  if (response.requestOptions.extra.containsKey('isRaw') &&
      response.requestOptions.extra['isRaw'] is bool &&
      response.requestOptions.extra['isRaw'] == true) {
    return response;
  }

  // Response body structural error
  if (!(response.data is Map)) {
    throw HttpError(
      requestOptions: response.requestOptions,
      response: response,
      type: DioErrorType.other,
      statusCode: response.statusCode ?? 0,
      errorCode: HttpErrorCode.unknownError,
      errorMessage: 'Response body is not an map.',
    );
  }
  if (!(response.data as Map).containsKey(codeKey)) {
    throw HttpError(
      requestOptions: response.requestOptions,
      response: response,
      type: DioErrorType.other,
      statusCode: response.statusCode ?? 0,
      errorCode: HttpErrorCode.unknownError,
      errorMessage: 'The `$codeKey` key does not exist in response body.',
    );
  }

  var data = response.data as Map;
  if (!(data[codeKey] is int)) {
    throw HttpError(
      requestOptions: response.requestOptions,
      response: response,
      type: DioErrorType.other,
      statusCode: response.statusCode ?? 0,
      errorCode: HttpErrorCode.unknownError,
      errorMessage:
          'The `$codeKey` key in the response body is not an [int] type.',
    );
  }

  // Response returns error
  if (data[codeKey] != successCode) {
    throw HttpError(
      requestOptions: response.requestOptions,
      response: response,
      type: DioErrorType.other,
      statusCode: response.statusCode ?? 0,
      errorCode: data[codeKey].toString(),
      errorMessage: data[messageKey] ?? 'unknown error',
    );
  }

  response.data = data[dataKey] ?? null;

  return response;
}