Validate Before Destroy

Question

I have three classes: School, Account, and Administratorship.

School

Answer 1

This is a Rails 5 answer, if you return false it will give a deprecation warning: "Returning false in Active Record and Active Model callbacks will not implicitly halt a callback chain in Rails 5.1".

def confirm_presence_of_alternate_administratorship_in_school
  return if school.administrators.count(["administratorships.account_id != #{id}"]) > 0
  errors[:base] << 'The school must have at least one administrator'
  throw :abort
end