# models/user_session.rb class UserSession < ActiveRecord::Base belongs_to :user before_validation :set_unique_key attr_accessor :username, :password def self.authenticate(key) self.find_by_key(key) end def self.new_by_user(user, env) user_session = UserSession.new( user: user, user_agent: env['HTTP_USER_AGENT'], ip: env['REMOTE_ADDR'] ) user_session.save user_session end private def set_unique_key self.key = SecureRandom.urlsafe_base64(32) end end