THis is the update controller:
def update
    @ad = Ad.find(params[:id])
    @ad.update_attributes(:id =>params)
    redirect_to "/ads/#{ @ad.id }"
  end

and this is the security controller:


  before_filter :check_logged_in, :only=> [:edit, :update, :destroy]

private
  def check_logged_in
  authenticate_or_request_with_http_basic("Ads") do |username, password|
    username == "admin" && password == "password"
  end
end