Decorator retrying connection with the callback on failure

retry.py

def retry(retries=3, callback_on_failure=None):
    """Retry requests method and run callback on failure

    Decorator will retry the decorated function for specified number of times,
    default is 3. If there is a callback passed, it will be called before
    calling the decorated function again. Callback allows to perform cleanups,
    clear the credentials, etc.
    Decorator will only work with functions that return requests.Request
    object, if decorated method returns other object result is returned with
    out retrying.

    Example:

    def callback(result, exc):
        if result.failed:
            print('Cleaning up')
        ...

    @retry(retries=2, callback_on_failure=callback)
    def grab_data_from_external_source():
        return requests.get('https://i.like.chorizo.es')

    If decorated function fails callback will be called before retrying.

    :param retries: number of retries of decorated function (Default value = 3)
    :type retries: int
    :param callback_on_failure: callback function to run on failure of
                                decorated function (Default value = None)
    :type callback_on_failure: func
    """
    def decorate(func):
        @wraps(func)
        def wrapper(*args, **kwargs):
            mretries = retries
            while mretries > 0:
                result = func(*args, **kwargs)
                try:
                    result.raise_for_status()
                except requests.HTTPError as exc:
                    logger.info(
                        'Retrying function call "{0}"'.format(func.func_name))
                    logger.exception('HTTPError raised')
                    try:
                        logger.debug('Calling callback function.')
                        callback_on_failure(result, exc)
                    except TypeError:
                        # no callback, silence it
                        pass
                    except Exception as exc:
                        # catching every error raised by callback
                        logger.exception(
                            'Callback "{0}" raised an exception.'.format(
                                callback_on_failure.func_name))
                    mretries -= 1
                except AttributeError:
                    logger.info('Result is not requests.Request type.')
                    return result
            return result
        return wrapper
    return decorate