Delegated types structure

rubyonrails-talk
1

Hi all. The name is Daveyon and I’m a huge fan of Basecamp becuse of its quirky look/design and how their DOM element is structured. I’ve learnt a lot by examine their DOM and network requests which I then piece together to make my rails app. I work as a full-time PHP/Node developer so I have no one to share ideas with. One thing I did noticed was Basecamp use of bucket and recordings. I never paid it any mind up until recent where some mentioned Delegated types on Youtube.

I think I got my head around it but I need some advice here. Let’s use Basecamp’s todo as an example but mine is called Task. Here’s my actual code:

class Bucket < ApplicationRecord
  belongs_to :account
  belongs_to :bucketable, polymorphic: true

  has_many   :recordings, dependent: :destroy
  has_many   :tasklists, through: :recordings, source: :recordable, source_type: 'Tasklist'
  has_many   :tasks, through: :recordings, source: :recordable, source_type: 'Task'
  has_many   :tasksets, through: :recordings, source: :recordable, source_type: 'Taskset'
  has_many   :fields, through: :recordings, source: :recordable, source_type: 'Field'


  def record(recordable, creator: Current.person, account: Current.account, children: nil, parent: nil, options: {})
    transaction do
      recordable.save!
      options.merge!(recordable: recordable, parent: parent, creator: creator)
      recordings.create!(options).tap do |recording|
        Array(children).each do |child|
          record child, creator: creator, account: account, parent: recording
        end
      end
    end
  end

  def incinerate(record)
    transaction do
      record.destroy!
    end
  end
end

This is the section I want to focus on:

class Recording < ApplicationRecord
  belongs_to :creator, class_name: "Person", foreign_key: :person_id
  belongs_to :bucket
  belongs_to :parent, class_name: "Recording", optional: true
  has_many :children, class_name: "Recording", foreign_key: :parent_id
  delegated_type :recordable, types: %w[ Taskset Field Tasklist Task ], dependent: :destroy
end

Field is a model that should not get delete when a Task is deleted. I could do @task.recording.children to see all it’s children, Yes, children should be deleted when the parent is deleted but in some cases, I want to be able to control that. To get around this, should I create another table with task_id and field_id OR record_id and field_id?

That new table would be called FieldTask:

[..]

delegated_type :recordable, types: %w[ Taskset FieldTask Tasklist Task ], dependent: :destroy

How would you guys approach this?

Thanks