Paranoia

Paranoia is a re-implementation of acts_as_paranoid for Rails 3, using much, much, much less code.

You would use either plugin / gem if you wished that when you called destroy on an Active Record object that it didn't actually destroy it, but just "hid" the record. Paranoia does this by setting a deleted_at field to the current time when you destroy a record, and hides it by scoping all queries on your model to only include records which do not have a deleted_at field.

You can use this gem with your default_scope, just replace default_scope with acts_as_paranoid. Example below.

I have tested it only with rails 3.1.

Installation & Usage

In your Gemfile:

gem 'paranoia', :git => git://github.com/legendetm/paranoia.git

Then run:

bundle install

Run your migrations for the desired models

class AddDeletedAtToClient < ActiveRecord::Migration
  def self.up
    add_column :clients, :deleted_at, :datetime
  end

  def self.down
    remove_column :clients, :deleted_at
  end
end

Usage

In your model:

class Client < ActiveRecord::Base
  acts_as_paranoid

  ...
end

or with your default scope

class Client < ActiveRecord::Base
  acts_as_paranoid where(:published => true)

  ...
end

Hey presto, it's there!

If you want a method to be called on destroy, simply provide a before_destroy callback:

class Client < ActiveRecord::Base
  acts_as_paranoid

  before_destroy :some_method

  def some_method
    # do stuff
  end

  ...
end

You can replace the older acts_as_paranoid methods as follows:

find_with_deleted(:all)       # => unscoped
find_with_deleted(:first)     # => unscoped.first
find_with_deleted(id)         # => unscoped.find(id)

find_only_deleted(:all)       # => only_deleted
find_only_deleted(:first)     # => only_deleted.first
find_only_deleted(id)         # => only_deleted.find(id)

Uniqueness validation

class Client < ActiveRecord::Base
  acts_as_paranoid

  validates :uniq_column, :uniqueness_without_deleted => true
  ...
end

License

This gem is released under the MIT license.