define dynamic class methods in model

gistfile1.rb

class << self
    attrs_without_id = AppConfig.column_names.delete_if {|x| x=='id'}
    default_values = {'pending_earned_buck_period'=>30*24*60, 'pending_refer_buck_period'=>60*24*60, 'refer_buck_valid_period'=>100*24*60, 'order_delivery_hold_period'=>3*24*60,'code_length'=>8}
    attrs_without_id.each do |attr|
      define_method(attr) do
        load_config
        @config && @config.send(attr) || default_values[attr]
      end
    end
end