PolymorphicJoin

Rails does not include a polymorphic join by default but this gem would help you to joins your polymorphic relationship with ease.

Add this line to your application's Gemfile:

gem 'polymorphic_join', '~> 0.2.1'

And then execute:

$ bundle

Or install it yourself as:

$ gem install polymorphic_join

Include the module inside your model

include PolymorphicJoin

Then you can use the polymorphic join like followings:

Given that I have this model call Notification

class Notification < ApplicationRecord
  belongs_to :notifiable, polymorphic: true
  include PolymorphicJoin
end

Then I can call:

Notification
  .ref_polymorphic(:notifiable)
  .where('notifiables.common_attribute' => 'test')
  .order('notifiables.common_attribute ASC')

Or if I want to specify only those types that I want to reference to:

Notification
  .ref_polymorphic(
    :notifiable, [:uploads, :comments]
  )
  .where('notifiables.common_attribute' => 'test')
  .order('notifiables.common_attribute ASC')

Or if you want to map back certain column

Notification
  .ref_polymorphic(
    :notifiable,
    [
      :comments,
      {
        uploads: { title: 'content' }
      }
    ]
  )
  .where('notifiables.common_attribute' => 'test')
  .order('notifiables.common_attribute ASC')

After checking out the repo, run bin/setup to install dependencies. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Bug reports and pull requests are welcome on GitHub at https://github.com/[USERNAME]/polymorphic_join. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

The gem is available as open source under the terms of the MIT License.

Everyone interacting in the PolymorphicJoin project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.