Question

I need to extend a model in a Rails 2.3.11 app without touching the original source file. I need to add a :has_many association in it. I’ve tried the approach mentioned in Extend model in plugin with "has_many" using a module without success. The class I need to extend is called UbiquoUser. Here the code I have in lib/extensions.rb:

module Sindicada
  module Extensions
    autoload :UbiquoUser, 'extensions/ubiquo_user'
  end
end
UbiquoUser.send(:extend, Sindicada::Extensions::UbiquoUser)

Here’s what I have in lib/extensions/ubiquo_user.rb:

module Sindicada
  module Extensions
    module UbiquoUser
      module ClassMethods

        def has_audio_favorites
          has_many :audios, :through => :audios_favorite
        end

      end #ClassMethods

    def self.included(base)
      base.extend(ClassMethods).has_audio_favorites
    end

    end #UbiquoUser
  end #Extensions
end #Sindicada

However, when I try to access the property audios of UbiquoUser on the app I get the error undefined method audios for class blablabla.

I also have the require 'extensions' in the environment.rb file and have checked that the files are being loaded.

Answer 1

The problem you have now is that you are extending your class, not including a module into it, so the Sicada::Extensions::UbiquoUser#included method never gets called.

To fix this, change this line:

UbiquoUser.send(:extend, Sindicada::Extensions::UbiquoUser)

to

UbiquoUser.send(:include, Sindicada::Extensions::UbiquoUser)