Historyable

A simple and solid concern to track ActiveRecord models attributes changes.

You may want to use PaperTrail or other ActiveRecord versioning libraries for a more thorough usage.

Installation

Add this line to your application’s Gemfile:

gem 'historyable'

And then execute

$ bundle install

Generate and run the migration to add the changes table:

$ rails generate historyable:install
$ rake db:migrate

Usage

# db/migrate/create_users.rb
class CreateUsers < ActiveRecord::Migration
  def change
    create_table :users do |t|
      t.string :first_name
      t.string :last_name
    end
  end
end

# app/models/user.rb
class User < ActiveRecord::Base
  include Historyable

  has_history :first_name, :last_name
end

And now you can:

u = User.new
u.first_name = 'Philippe'
u.save

u.first_name_history
# => [
        {
          "attribute_value" => "Philippe",
          "changed_at" => Tue, 20 Aug 2013 16:20:00 UTC +00:00
        }
      ]


u.first_name = 'Jean-Philippe'
u.save
u.first_name_history
# => [
        {
          "attribute_value" => "Jean-Philippe",
          "changed_at" => Tue, 20 Aug 2013 16:20:10 UTC +00:00
        },
        {
          "attribute_value" => "Philippe",
          "changed_at" => Tue, 20 Aug 2013 16:20:00 UTC +00:00
        }
      ]

Known shortcomings

It is not possible to directly query attribute values since model attributes tracked by Historyable are serialized in the database.

To overcome this limitation, Historyable also exposes the raw ActiveRecord polymorphic relation.

u.first_name_history_raw
# => #<ActiveRecord::Relation [#<Change id: nil, object_attribute_value: "Jean-Philippe", created_at: "2013-08-20 16:20:10">], [#<Change id: nil, object_attribute_value: "Philippe", created_at: "2013-08-20 16:20:00">]>

Contributing

See CONTRIBUTING.md for more details on contributing and running test.

Credits

historyable is maintained and funded by hooktstudios.