Connection closed before full header was received http post in flutter

Question

I'm having problems trying to consume my API, and after following up on this problem I'm stuck in the matter and I've tried different emulators in various versions and the problem persists.

Error:

DioError [DioErrorType.other]: HttpException: Connection closed before full header was received, uri = http://10.0.2.2:7108/Users/authenticate

Flutter doctor

Http Post

class AuthenticateRemoteApi extends AuthenticateGateway {
  final AuthenticateMapper _authenticateMapper = AuthenticateMapper();

  @override
  Future<SesionUser> login(Authenticate user) async {
    var dio = Dio();
    dio.options.headers['content-Type'] = 'application/json';
    String url = 'http://10.0.2.2:7108/Users/authenticate';

    try {
      Response response = await dio.post(url, data: authenticateModelToJson(user));
      return _authenticateMapper.fromMap(jsonDecode(response.data));
    } catch (e) {
      throw Exception(e);
    }
  }
}

Answer 1

I have came with this work around by creating this interceptor.

The idea of it is when encountering this random error just to retry the request.

/// Interceptor
class RetryOnConnectionChangeInterceptor extends Interceptor {
  final Dio dio;

  RetryOnConnectionChangeInterceptor({
    required this.dio,
  });

  @override
  void onError(DioError err, ErrorInterceptorHandler handler) async {
  if (_shouldRetryOnHttpException(err)) {
      try {
        handler.resolve(await DioHttpRequestRetrier(dio: dio).requestRetry(err.requestOptions).catchError((e) {
          handler.next(err);
        }));
      } catch (e) {
        handler.next(err);
      }
    } else {
      handler.next(err);
    }

  }

  bool _shouldRetryOnHttpException(DioError err) {
    return err.type == DioErrorType.other &&
        ((err.error is HttpException && err.message.contains('Connection closed before full header was received')));
  }
}

/// Retrier
class DioHttpRequestRetrier {
  final Dio dio;

  DioHttpRequestRetrier({
    required this.dio,
  });

  Future<Response> requestRetry(RequestOptions requestOptions) async {
    return dio.request(
      requestOptions.path,
      cancelToken: requestOptions.cancelToken,
      data: requestOptions.data,
      onReceiveProgress: requestOptions.onReceiveProgress,
      onSendProgress: requestOptions.onSendProgress,
      queryParameters: requestOptions.queryParameters,
      options: Options(
        contentType: requestOptions.contentType,
        headers: requestOptions.headers,
        sendTimeout: requestOptions.sendTimeout,
        receiveTimeout: requestOptions.receiveTimeout,
        extra: requestOptions.extra,
        followRedirects: requestOptions.followRedirects,
        listFormat: requestOptions.listFormat,
        maxRedirects: requestOptions.maxRedirects,
        method: requestOptions.method,
        receiveDataWhenStatusError: requestOptions.receiveDataWhenStatusError,
        requestEncoder: requestOptions.requestEncoder,
        responseDecoder: requestOptions.responseDecoder,
        responseType: requestOptions.responseType,
        validateStatus: requestOptions.validateStatus,
      ),
    );
  }
}

Usage: add this interceptor [RetryOnConnectionChangeInterceptor] to your Dio client instance