How to check the authorization in the service through Facebook?

Question

Facebook

Let's say I have a service that provides a REST API.
There is an API client for iOS and Android.
It is necessary to make it so that customers are authorized through Facebook and can work with the service.
Now I did it through facebook sdk, but how to check server authorization?

Answer 1

I asked M. Zuckerberg, he gladly agreed to help. Here is a link to his page, say that you are from Sergei Konstantinovich - he knows! Good luck.
ps Do not troll for humor, just a good mood!

Answer 2

In theory, the client should send user data to the server. But the client's data cannot be trusted ...
So far, only the digital signature of this data and the verification of this signature on the server come to mind.

Answer 3

Like this: https://developers.facebook.com/docs/facebook-logi...