How to hide records, rather than delete them (soft delete from scratch)

Question

Let\'s keep this simple. Let\'s say I have a User model and a Post model:

class User < ActiveRecord::Base
    # id:integer name:         


        

Answer 1

I usually use a field named deleted_at for this case:

class Post < ActiveRecord::Base
  scope :not_deleted, lambda { where(deleted_at: nil) }
  scope :deleted, lambda { where("#{self.table_name}.deleted_at IS NOT NULL") }

  def destroy
    self.update_attributes(deleted_at: DateTime.current)
  end

  def delete
    destroy
  end

  def deleted?
    self.deleted_at.present?
  end
  # ...

---

Want to share this functionnality between multiple models?

=> Make an extension of it!

# lib/extensions/act_as_fake_deletable.rb
module ActAsFakeDeletable
  # override the model actions
  def destroy
    self.update_attributes(deleted_at: DateTime.current)
  end

  def delete
    self.destroy
  end

  def undestroy # to "restore" the file
    self.update_attributes(deleted_at: nil)
  end

  def undelete
    self.undestroy
  end

  # define new scopes
  def self.included(base)
    base.class_eval do
      scope :destroyed, where("#{self.table_name}.deleted_at IS NOT NULL")
      scope :not_destroyed, where(deleted_at: nil)
      scope :deleted, lambda { destroyed }
      scope :not_deleted, lambda { not_destroyed }
    end
  end
end

class ActiveRecord::Base
  def self.act_as_fake_deletable(options = {})
    alias_method :destroy!, :destroy
    alias_method :delete!, :delete
    include ActAsFakeDeletable

    options = { field_to_hide: :content, message_to_show_instead: "This content has been deleted" }.merge!(options)

    define_method options[:field_to_hide].to_sym do
      return options[:message_to_show_instead] if self.deleted_at.present?
      self.read_attribute options[:field_to_hide].to_sym
    end
  end
end

Usage:

class Post < ActiveRecord::Base
  act_as_fake_deletable

Overwriting the defaults:

class Book < ActiveRecord::Base
  act_as_fake_deletable field_to_hide: :title, message_to_show_instead: "This book has been deleted man, sorry!"

Boom! Done.

Warning: This module overwrite the ActiveRecord's destroy and delete methods, which means you won't be able to destroy your record using those methods anymore. Instead of overwriting you could create a new method, named soft_destroy for example. So in your app (or console), you would use soft_destroy when relevant and use the destroy/delete methods when you really want to "hard destroy" the record.