global methods in ruby on rails models

Question

I have methods in all of my models that look like this:

def formatted_start_date
  start_date ? start_date.to_s(:date) : nil
end

I would like

Answer 1

It looks more like something for a helper to me. Try this in the your application help:

def formatted_date(date)
   date ? date.to_s(:date) : nil
end

Formatting isn't something that really belongs in the model (for precisely the reason you've discovered... putting such common code in every model is annoying)

If you really want to do as you say though, then what you could do is monkeypatch the ActiveRecord superclass and add the function you want into there. It would then be available for all your models. Beware that monkeypatching can lead to unpredictable and undefined behaviour and use at your own risk! It's also pretty hacky :)

class ActiveRecord::Base
   def formatted_start_date
      start_date ? start_date.to_s(:date) : nil
   end
end

Just stick that somewhere that will be run before anything else in your app will be, and it will dynamically add the method to the base class of your models, making it available for use.

Or you could create a mixin for all your models, but that seems a bit overkill for a single method.