How to register and authorize a user on the site through the OAuth Vkontakte API, Facebook API and other social networks?

Question

Social media

I'm sending the user to login to a third party site. I received a token, I request information about the user, for example, his ID and e-mail. For registration, I write this ID to the database with the flag of the social network where it came from, and for authorization, I request this ID with the flag and authorize.
I want that, no matter where the user comes from: Facebook, Vkontakte, Mail.ru or my own registration, they have one account.
Can you tell me if such a system is possible?
Do all social networks give me an e-mail (and if it is hidden by privacy settings)?

Answer 1

Some social networks give email, some do not.
It is best to use ready-made libraries if you do not really delve into the essence. For PHP, I recommend HybridAuth .

Answer 2

It all depends on how seriously you plan to deal with your resource. If you just need authorization, then perhaps it’s really better to use a third-party service.
If there are other improvements, then of course it is better to deal with the api once. Email does not give a tweeter and seems to be VKontakte. Plus, a user can have different mailboxes in different accounts.
In your case, it’s probably easier when a user logs in from any social network, just look in which browser he is still logged in and bring the accounts together.

Answer 3

If you do not want to delve deeply, use ulogin.ru/
Not all social. networks give the email address. mail, so it has to be requested additionally.

Answer 4

Thank you. I will use.

Answer 5

It's best not to focus on email, f bc

Answer 6

It has long been in a favorite post . No time to implement.