'Log error info when exception occurred.'

def process_exception(self, request, exception):

    log_format = self._get_log_format(request)
    if (log_format is None):
        return
    params = self._get_parameters_from_request(request, True)
    params['message'] = exception
    params['http_status'] = '-'
    self.OPERATION_LOG.info(log_format, params)
