user.rb

class User < ActiveRecord::Base
  has_many :receipts

  include Authentication
  include Authentication::ByPassword

  validates_presence_of     :login
  validates_length_of       :login,    :within => 3..40
  validates_uniqueness_of   :login

  attr_accessible :login, :name, :password, :password_confirmation

  def self.authenticate(login, password)
    return nil if login.blank? || password.blank?
    u = find_by_login(login.downcase) # need to get the salt
    u && u.authenticated?(password) ? u : nil
  end
end