IdentityMap

Adds simple hand controlled identity map for ActiveRecord.

Installing

in Rails 2.3 in config/environment.rb

config.gem 'ar-simple-idmap', :lib => 'identity_map'

in Rails 3 in Gemfile

gem 'ar-simple-idmap', :require => 'identity_map'

Enabling

To enable in ApplicationController (it is not enabled by default).

class ApplicationController < ActionController::Base
  use_identity_map #(installs around filter)
  # or use_identity_map :only=>[:index, :show]
  # or use_identity_map :except=>[:update]
end

If you decide to disable filter in sub controllers:

class ClientController < ApplicationController
  dont_use_identity_map :only=>[:save, :update, :messy_action]
end

Then you should enable identity map for each model class individually:

class TarifPlan < ActiveRecord::Base
  use_id_map
  has_many :clients
end

class Client < ActiveRecord::Base
  use_id_map
  belongs_to :tarif_plan
end

You can use identity map for all models by writing in initializer:

class ActiveRecord::Base
  use_id_map
end

To enable in rake task or script:

ActiveRecord::Base.with_id_map do
  # all things here goes with identity map
end

or equivalently

Client.with_id_map do
  # all things here goes with identity map
  # not only for Client
end

If you found that identity logic does wrong thing in some particular place, you could temporary disable it:

ActiveRecord::Base.without_id_map do
  # all things here goes without identity map
end

Client.without_id_map do
  # all things here goes without identity map
  # not only for Client
end

class ClientsController
  def strange_action
    without_identity_map do
      do_strange_things_without_identity_map
    end
  end
end

IdentityMap

Installing

Enabling

Copyright