Question

So I have a Task model, a Ticket model and a Category model.

Category has_many Tasks
Ticket has_many Tasks
Category has_many Tickets
Ticket belongs_to Category
Task belongs_to Ticket
Task belongs_to Category

The Tasks that are associated to a Category are the default Tasks for a Ticket when the Category is linked to a Ticket. So I need the Tasks that are associated to a Category to be duplicated and associated to the Ticket when a Category is selected for the Ticket.

I’m wondering if I can do something like this in my Ticket model:

  after_create :duplicate_tasks_to_ticket
  after_update :duplicate_tasks_to_ticket

  def duplicate_tasks_to_ticket
    if self.tasks.blank?
      for task in self.category.tasks.all
        new_task = Task.new
        new_task.name = task.name
        new_task.ticket_id = self.id
        new_task.save
      end
    end
  end

Right now this doesn’t throw any errors but it doesn’t do anything. Any help would be greatly appreciated. Thanks!

Answer 1

If you are already associating them to the category, why do they need to be associated to the ticket also? If you need the granularity of being tied to a ticket, then just use that association to get all tasks under a category. Tieing them to both just make site complicated. Now, if you absolutely need to tie them to both, you should create an assignment table for that, which stores category_id, task_id. Another assignment table for ticket_id, task_id. Then keep the task as one record, as supposed to duplicating data.

Your code looks fine for the most part. I don’t think you need the .all at the end. The associations will automatically load all that you are referencing under that model.

Though try using the association build method instead:

def duplicate_tasks_to_ticket
  if self.tasks.blank?
    for task in self.category.tasks.all
      self.tasks.build(:name => task.name)
    end
    self.save
  end
end

The build creates a new object of that association, assigning the foreign key for you. Then you just call save on the parent model, and it will do all the proper insert statements.