How to allow users of my site to login/register via Facebook and integrate Facebook login system with my own login system?

facebook, php

Solution

First, you need to register an facebook app at https://developers.facebook.com/apps. Then this code will be a good starting point for you:

<iframe src="https://www.facebook.com/plugins/registration?
             client_id=YOUR_APP_ID&
             redirect_uri=https%3A%2F%2Fdevelopers.facebook.com%2Ftools%2Fecho%2F&
             fields=name,birthday,gender,location,email"
        scrolling="auto"
        allowTransparency="true"
        width="100%"
        height="400">
</iframe>

Full documentation of the registration plugin can be found here: https://developers.facebook.com/docs/plugins/registration/

Problem

I am just lost and do not know where to begin, please show me documentation I can read to let users register/login to my site using Facebook. Assuming that - I have my own registration/login system How can I - Log in users with their Facebook profile - Register users quickly with their Facebook profile if they are not registered Any ideas or docs are appreciated.

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