Authenticating via an API with Clearance

Hi all, I’m using Clearance for my authentication and I want to have my iPad app login.

I set up a session controller with methods called api_authentication and api_signout

  def api_authenticate  
    @user = User.authenticate params[:email], params[:password]
    sign_in(@user) do |status|
      if status.success?
         some_code?
      else
         some_code?
      end
    end
end

def api_signout

end

I’m a bit confused about what my api_authenticate method should return. What do I need to send back so my app will be logged in? Also what’s best practice, should I be using the sign_in method, or perhaps just returning the data I want to use (like user_id associated with current_user) as a json object?

Any advice/code/articles/ appreciated!

-Roneesh