Question

So a while ago I created a small module to serve as the methods I need for a votable polymorphic association, and while it was originally meant to be used only for ActiveRecord I now want to use it with mongo, and since I’m using mongoid all of the methods for the associations I need to create in this intance have the same names and everthing here take a look at my previous code:

# config/initializers/acts_as_votable.rb

module ActsAsVotable

end

module ActiveRecord
  class Base
    class << self
      cattr_accessor :votable

      def acts_as_votable
        has_many :votes, :as => :voteable
      end

      def acts_as_voter
        has_many :votes, :as => :voter
      end

      def votable?
        method_defined? :votes
      end
    end

    def votable?
      self.class.send(:method_defined?, :votes)
    end
  end
end

And here is how it was used:

class Recipe < ActiveRecord::Base
  acts_as_votable
  # more stuff...
end

So you’ll notice two issues here, firstly, I’m extending ActiveRecord::Base, how can I make this work for any model, not just ones that inherit from ActiveRecord?, Secondly do I actually need an empty module like that ActsAsVotable one? What am I doing wrong here?

If I just put all that code into the module ActsAsVotable, shouldn’t I just be able to call includes ActsAsVotable from my model?

Answer 1

First, put this in an initializer or in /lib but be sure the path is loaded in your application.

module ActsAsVotable

  extend ActiveSupport::Concern

  module InstanceMethods
    def votable?
      self.class.send(:method_defined?, :votes)
    end
  end

  module ClassMethods
    cattr_accessor :votable

    def acts_as_votable
      has_many :votes, :as => :voteable
    end

    def acts_as_voter
      has_many :votes, :as => :voter
    end

    def votable?
      method_defined? :votes
    end

  end
end

Then in any model:

class User < ActiveRecord::Base

  include ActsAsVotable

end

Finally:

User.methods.include?("acts_as_votable") # => true