Empty OAuth requests?

Question

Facebook

There is an application on Node.js in which authorization is made through social networks (Vkontakte, Facebook, Odnoklassniki). Authorization works through the OAuth protocol ( https://vk.com/dev/authcode_flow_user). There is also an Android application that uses authorization through social networks. Authorization works fine on the site and in the mobile application.
The problem is that empty requests (without parameters) periodically come at the very moment when the authorization code is received, which should be used later to obtain an access_token. For example, after redirecting a user to a special url to allow authorization, a GET request with an authorization code to redirect_url should be sent to the server. Empty requests without an authorization code come from Vkontakte, Facebook and Odnoklassniki. I see it in the logs.
Has anyone encountered a similar problem? I just don't want to lose users.
Thank you.

Answer 1

Perhaps this happens when the user clicks "cancel" rather than "allow"