ActiveRecord-Userstamp

Userstamp extends ActiveRecord::Base to add automatic updating of creator, updater, and deleter attributes. It is based loosely on ActiveRecord::Timestamp.

Two class methods (model_stamper and stampable) are implemented in this gem. The model_stamper method is used in models that are responsible for creating, updating, or deleting other objects. Typically this would be the User model of your application. The stampable method is used in models that are subject to being created, updated, or deleted by stampers.

This is a fork of:

• the magiclabs-userstamp gem
• which is a fork of Michael Grosser's [userstamp gem] (https://github.com/grosser/userstamp)
• which is a fork of the original userstamp plugin by delynn

In addition to these, I have cherry picked ideas and changes from the following forks:

• simplificator
• akm
• konvenit

Finally, this gem only supports Ruby 2.0 and above. Yes, you really should upgrade to a supported version of Ruby. This gem is tested only on Rails 4.2; but it should work with Rails 4+.

The reason for this is because the original userstamp plugin does not support databases utilising soft deletes. They are not tested explicitly within this gem, but it is expected to work with the following gems:

• acts_as_paranoid
• paranoia

The stampable method has been modified to allow additional arguments to be passed to the creator/updater relations. This allows declarations like:

  stampable with_deleted: true

to result in a belongs_to relation which looks like:

  belongs_to :creator, class_name: '::User', foreign_key: :created_by, with_deleted: true

Do create a ticket if it is broken, with a pull-request if possible.

While examining the userstamp gem's network on Github, it was noticed that quite a few forks were made to allow customisability in the name and type of the column with the database migration.

This gem now supports customised column names. See the usage section on the configuration options supported.

This fork includes changes to perform model stamping before validation. This allows models to enforce the presence of stamp attributes:

  validates :created_by, presence: true
  validates :updated_by, presence: true

Furthermore, the creator attribute is set only if the value is blank allowing for a manual override.

Assume that we are building a blog application, with User and Post objects. Add the following to the application's Gemfile:

  gem 'activerecord-userstamp'

Define an initializer in your Rails application to configure the gem:

ActiveRecord::Userstamp.configure do |config|
  # config.default_stamper = 'User'
  # config.creator_attribute = :creator_id
  # config.updater_attribute = :updater_id
  config.deleter_attribute = nil
end

By default, :deleter_attribute is set to :deleter_id for soft deletes. If you are not using soft deletes, you can set the attribute no nil.

Ensure that each model has a set of columns for creators, updaters, and deleters (if applicable.)

  class CreateUsers < ActiveRecord::Migration
    def change
      create_table :users do |t|
        ...
        t.userstamps
      end
    end
  end

  class CreatePosts < ActiveRecord::Migration
    def change
      create_table :posts do |t|
        ...
        t.userstamps
      end
    end
  end

If you use protect_from_forgery, make sure the hooks are prepended:

class ApplicationController < ActionController::Base
  protect_from_forgery with: :exception, prepend: true # with: anything will do, note `prepend: true`!
end

Declare the stamper on the User model:

  class User < ActiveRecord::Base
    model_stamper
  end

If your stamper is called User, that's it; you're done.

The association which is created on each of the creator_id, updater_id, and deleter_id can be customised. Also, the stamper used by each class can also be customised. For this purpose, the ActiveRecord::Base.stampable method can be used:

  class Post < ActiveRecord::Base
    stampable
  end

The stampable method allows you to customize the creator, updater, and deleter associations. It also allows you to specify the name of the stamper for the class being declared. Any additional arguments are passed to the belongs_to declaration.

The major difference between 1.x and 2.x is the naming of the columns. This version of the gem allows specifying the name of the column from the gem configuration:

ActiveRecord::Userstamp.configure do |config|
  config.creator_attribute = :created_by
  config.updater_attribute = :updated_by
  config.deleter_attribute = :deleted_by
end

Within migrations, it was possible to declare t.userstamps within a table definition. It used to accept one argument, which declares whether the deleter column should be created. This has been changed to respect the gem configuration's deleter_attribute. If that is nil, then no deleter column would be created.

There is also no need to include the Userstamp module in ApplicationController.

That version of the gem allows every model to declare the name of the column containing the attribute. That also means that in a large project, every model needs to declare stampable, which is not very DRY.

To use this gem, normalise all database columns to use a consistent set of column names. Configure the gem to use those names (as above) and remove all stampable declarations.

There is no need to include the Userstamp module in ApplicationController.

Run

$ bundle exec rspec

• DeLynn Berry: The original idea for this plugin came from the Rails Wiki article entitled Extending ActiveRecord
• Michael Grosser
• John Dell
• Chris Hilton
• Thomas von Deyen
• Joel Low