ar_binary_flag_attributes¶ ↑

Adds many binary/flag attributes to your AR model using only one integer field.

Simply as hell :) First, add integer column called ‘flags’ (default) or whatever you like.

class AddFlagsToUserMigration < ActiveRecord::Migration
  def self.run
    add_column :users, :flags, :integer
  end
end

Then add one line to your model so it should look like this:

class User < ActiveRecord::Base
  binary_attributes [:a, :b, :c]
end

You can divide all flags into more integer columns, or use non default column name.

class AnotherMigration < ActiveRecord::Migration
  def self.run
    add_column :phones, :features, :integer
    add_column :phones, :minor_features, :integer
  end
end

class Phone < ActiveRecord::Base
  binary_attributes [:camera, :wlan, :touchscreen], :features
  binary_attributes [:sd_card_slot, :qwerty_keyboard], :minor_features
end

And try:

p = Phone.new
p.camera = true
p.qwerty_keyboard = true
p.save

p.features => 1
p.minor_features => 2

You can specify custom masks if you want to:

class Building < ActiveRecord::Base
  flag_attributes(
    "overdriven"                => 0b00000001,
    "with_points"               => 0b00000010
  )
end

There is a more powerful tool here github.com/pboling/flag_shih_tzu

Core author - Artūras Šlajus (github.com/arturaz/ar_binary_flag_attributes/blob/master/init.rb). I just added spec, and made a gem :]

Copyright © 2011, 2012 Artūras Šlajus, Aleksander Kwiatkowski. See LICENSE.txt for further details.