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Ruby

Posted by Andrew Cottage
Andrew Cottage
20,718 Points

Rails Callback that Opens a New Thread, Checks a Condition, and Destroys Self if Condition is true.

Hello all.

I'm trying to write a callback that opens a new thread, checks a condition, and destroys self if condition is true. 

after_create :verify_statute

  def verify_statute
    if Rails.env != 'test'
      Thread.new do 
        sleep(15)
        if self.statutes.empty?
          self.destroy
        end
      end
    end
  end

I have it working but want to know if this is the correct way to require an associated record. Usually a record is created then a few seconds after that the associated record may or may not be created. If that association never gets created I want to destroy the original record. Also any ideas on how I would test a callback like this?

1 Answer

Ethan Lowry
PLUS
Ethan Lowry
Courses Plus Student 7,323 Points
Ethan Lowry
Ethan Lowry
Courses Plus Student 7,323 Points

This seems like a slightly unusual use case - would a better option not be to set validation on the 'parent' model so that it cannot be created without the association being provided?

e.g. validates :statutes, presence: true ?

Andrew Cottage
Andrew Cottage
20,718 Points

Thanks for the reply Ethan.

That does seem better, but usually the statutes association is created within seconds of the parent model. It saves time for me to save the parent model before creating the statute association. I will look into refactoring my code to save everything at once and update the thread here if that is a working solution.

Thanks