Unable to catch Flutter Dio exception

dio_exception.md

I found a hacky solution. We are overriding all the exceptions thrown by default. Then we are going to create custom interceptor to handle and throw exceptions. This way we can catch the DioException as we did before.

1. Create a base client like this. You have to set validateStatus function to return true whatever the status code is.

final baseOptions = BaseOptions(
  baseUrl: host,
  contentType: Headers.jsonContentType,
  validateStatus: (int? status) {
    return status != null;
    // return status != null && status >= 200 && status < 300;
  },
);

final dio = Dio(baseOptions);

2. Create a custom interceptor to raise exceptions

class ErrorInterceptor extends Interceptor {
  @override
  void onResponse(Response response, ResponseInterceptorHandler handler) {
    final status = response.statusCode;
    final isValid = status != null && status >= 200 && status < 300;
    if (!isValid) {
      throw DioException.badResponse(
        statusCode: status!,
        requestOptions: response.requestOptions,
        response: response,
      );
    }
    super.onResponse(response, handler);
  }
}

3. Add that to the Dio interceptors list

dio.interceptors.addAll([
    ErrorInterceptor(),
]);