How can I blacklist usernames with Devise?

blacklist, devise, registration

Solution

There was an easier way to do this than having to modify Devise's controllers.

In the `User` model all I had to do was:

validates :username, :exclusion => %w(about blog ...)

Way too simple.

Problem

I have Devise setup to allow login with email or username. With your username you can have a vanity URL like so: `vanity.com/username`. My User model thus has `attr_accessible :username` as well as `attr_accessor :login`. To prevent usernames from colliding with future features, I want to implement a blacklist on certain usernames. You can see a nice example list in use by GitHub here. I'm new to Devise and have searched the how-to's in their wiki to see if this use case or anything like it is covered there. It doesn't seem to be. How can I blacklist certain usernames for registration in Devise?

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