Passing a defined method unless an attribute is present?

Question

Having newbie trouble getting this working. I have Stores that don't have addresses (just a website) as well so the gem (Google-Maps-for-Rails) when seeding actually doesn't create them at all but only the ones with an address.

Store.rb

validates :address, 
          :presence => {:unless => :website, 
          :message => "You must enter an address, website, or both."}

acts_as_gmappable :check_process => :prevent_geocoding,
                  :address => "address", 
                  :normalized_address => "address",
                  :msg => "Sorry, unable to find address."


# How do I correct this block?
def prevent_geocoding
  unless website.present? 
   address.blank? || (!latitude.blank? && !longitude.blank?)
  end
end

I still want to use everything here but what's the correct way to pass this block?

Thank you.

Answer 1

You're on the right track. You can bypass validations by passing a method into if or unless as options on the validation. In the above code, you're passing it as an option to the presence validator and not to the validation itself. Move the unless out of the hash and pass it the name of a method or a Proc — really anything that returns true or false. Here's an example:

validates :address, 
          :presence => { :message => "You must enter an address, website, or both." },
          :unless => Proc.new { |store| store.address.nil? && store.website.present? }

That validation will run every time except in cases where the store both doesn't have an address and does have a website. If you need more complex logic, I recommend moving that out of a Proc and into a method.