How to request an email input when logging in via VK?

Question

Open ID

The Bitrix site uses social login. network, made on the basis of a standard component of social services. VK does not give the user's email.
How can I request an email input from the user after logging in via VKontakte?

Answer 1

When a user registers via social networks, the OnAfterSocServUserAdd event fires. In its handler, you can either put the user in the desired group, or in some other way mark that the person is from VK and without email.
Then, when logging in, look to see if the person is in the group we need or not, and if he is, then send him to the page with the email input.
A crutch, of course.