How to simplify the soft delete process with Ruby on Rails?
Just use a concern in rails 4
Example here
module SoftDeletable
extend ActiveSupport::Concern
included do
default_scope { where(is_deleted: false) }
scope :only_deleted, -> { unscope(where: :is_deleted).where(is_deleted: true) }
end
def delete
update_column :is_deleted, true if has_attribute? :is_deleted
end
def destroy;
callbacks_result = transaction do
run_callbacks(:destroy) do
delete
end
end
callbacks_result ? self : false
end
def self.included(klazz)
klazz.extend Callbacks
end
module Callbacks
def self.extended(klazz)
klazz.define_callbacks :restore
klazz.define_singleton_method("before_restore") do |*args, &block|
set_callback(:restore, :before, *args, &block)
end
klazz.define_singleton_method("around_restore") do |*args, &block|
set_callback(:restore, :around, *args, &block)
end
klazz.define_singleton_method("after_restore") do |*args, &block|
set_callback(:restore, :after, *args, &block)
end
end
end
def restore!(opts = {})
self.class.transaction do
run_callbacks(:restore) do
update_column :is_deleted, false
restore_associated_records if opts[:recursive]
end
end
self
end
alias :restore :restore!
def restore_associated_records
destroyed_associations = self.class.reflect_on_all_associations.select do |association|
association.options[:dependent] == :destroy
end
destroyed_associations.each do |association|
association_data = send(association.name)
unless association_data.nil?
if association_data.is_deleted?
if association.collection?
association_data.only_deleted.each { |record| record.restore(recursive: true) }
else
association_data.restore(recursive: true)
end
end
end
if association_data.nil? && association.macro.to_s == 'has_one'
association_class_name = association.options[:class_name].present? ? association.options[:class_name] : association.name.to_s.camelize
association_foreign_key = association.options[:foreign_key].present? ? association.options[:foreign_key] : "#{self.class.name.to_s.underscore}_id"
Object.const_get(association_class_name).only_deleted.where(association_foreign_key, self.id).first.try(:restore, recursive: true)
end
end
clear_association_cache if destroyed_associations.present?
end
end
Deletable
A rails concern to add soft deletes.
Very simple and flexible way to customise/ change
(You can change the delete column to be a timestamp and change the methods to call ActiveRecord touch ).
Best where you want to control code not have gems for simple tasks.
Usage
In your Tables add a boolean column is_deletable
class AddDeletedAtToUsers < ActiveRecord::Migration
def change
add_column :users, :is_deleted, :boolean
end
end
In your models
class User < ActiveRecord::Base
has_many :user_details, dependent: :destroy
include SoftDeletable
end
Methods and callbacks available:
User.only_deleted
User.first.destroy
User.first.restore
User.first.restore(recursive: true)
Note: Focus Using update_column or touch if you decide to use a timestamp column.
Edited
If you are using rails <= 3.x (this example also use a DateTime field instead boolean), there are some differences:
module SoftDeletable
extend ActiveSupport::Concern
included do
default_scope { where(deleted_at: nil }
# In Rails <= 3.x to use only_deleted, do something like 'data = Model.unscoped.only_deleted'
scope :only_deleted, -> { unscoped.where(table_name+'.deleted_at IS NOT NULL') }
end
def delete
update_column :deleted_at, DateTime.now if has_attribute? :deleted_at
end
# ... ... ...
# ... OTHERS IMPLEMENTATIONS ...
# ... ... ...
def restore!(opts = {})
self.class.transaction do
run_callbacks(:restore) do
# Remove default_scope. "UPDATE ... WHERE (deleted_at IS NULL)"
self.class.send(:unscoped) do
update_column :deleted_at, nil
restore_associated_records if opts[:recursive]
end
end
end
self
end
alias :restore :restore!
def restore_associated_records
destroyed_associations = self.class.reflect_on_all_associations.select do |association|
association.options[:dependent] == :destroy
end
destroyed_associations.each do |association|
association_data = send(association.name)
unless association_data.nil?
if association_data.deleted_at?
if association.collection?
association_data.only_deleted.each { |record| record.restore(recursive: true) }
else
association_data.restore(recursive: true)
end
end
end
if association_data.nil? && association.macro.to_s == 'has_one'
association_class_name = association.options[:class_name].present? ? association.options[:class_name] : association.name.to_s.camelize
association_foreign_key = association.options[:foreign_key].present? ? association.options[:foreign_key] : "#{self.class.name.to_s.underscore}_id"
Object.const_get(association_class_name).only_deleted.where(association_foreign_key, self.id).first.try(:restore, recursive: true)
end
end
clear_association_cache if destroyed_associations.present?
end
end
Usage
In your Tables add a DateTime column deleted_at
class AddDeletedAtToUsers < ActiveRecord::Migration
def change
add_column :users, :deleted_at, :datetime
end
end
Try this gem : https://github.com/technoweenie/acts_as_paranoid - ActiveRecord plugin allowing you to hide and restore records without actually deleting them