In my application users can register an account normally (with username, email, password) or using Google or Facebook.
What message should be shown if a user is trying to login to my application with a username/email that is already taken by the provider (Google, Facebook)?
google:user@gmail.com
) the same as an account created via email, with the same account (email:user@gmail.com
)? In other words, would it solve your problem if you only evaluated conflicts within a chosen identification method (e.g. creating an account via Facebook would only check that the chosen FB profile is not already associated to an existing account)? – maxathousand May 1 '20 at 15:28