buildHttpRunner<T> function

HttpRunner<T> buildHttpRunner<T>(HttpRunnerAction<T> action)

Create API functions with perfect error handling.

var http = Http.getInstances(HttpBaseOptions({
  name: 'defaultApi',
  baseUrl: 'http://domain.com/api/v1',
}));

class UserApi {
  static final getUser = buildHttpRunner<UserEntity>((HttpRunnerParams params) async {
    var res = await http.get('/user/${params.params?['id']??1}',
      queryParameters: {
        'getFullData': params.params?['getFullData'] ?? '0',
      },
      cancelToken: params.cancelToken);

    return UserEntity.fromJson(res.data);
  });
}

try {
  var user = await UserApi.getUser(HttpRunnerParams(
    params: {'id': 123, 'getFullData': 1},
  ));
  if (user == null) {
    print('Request cancelled!');
  }
} on HttpError catch (e) {
  if (e.errorCode == HttpErrorCode.notFound) {
    print('The user could not be found');
  }
}

Implementation

HttpRunner<T> buildHttpRunner<T>(HttpRunnerAction<T> action) {
  return (HttpRunnerParams? params) async {
    try {
      return await action(params ?? HttpRunnerParams());
    } on HttpError catch (e) {
      throw e;
    } on DioError catch (e) {
      if (e.type == DioErrorType.cancel) {
        return null;
      }

      int statusCode = e.response?.statusCode ?? 0;
      throw HttpError(
        requestOptions: e.requestOptions,
        response: e.response,
        type: e.type,
        error: e.error,
        statusCode: statusCode,
        errorCode: HttpErrorCode.unknownError,
        errorMessage: null,
        errorData: e.response?.data,
      );
    }
  };
}