Facebook Login - WordPress Integration without plugin

Question

What is the workflow involved in Login with Facebook on WordPress ?

I understand that this question has been asked several times, but none of the previous threads have the answer I'm looking for.

I have a working knowledge of OAuth 2.0 that Facebook currently uses and I'm familiar with the WordPress API. What I need to know is how does one use the data they get from the OAuth 2.0 to implement a register/login function in WordPress.

Is there a function to "log in" a user if the email id is provided ? Or to register a user based on the email id, first name, last name, etc.

Answer 1

wp_create_user take username password and email, to create a new user,

Instead if you want to get it by email you can use get_user_by

You can find more at the users and authors section of wordpress codex