I am using RoR ActiveRecord polymorphic inheritance and was wondering if it's possible to access the base class' association methods in the invocation of either to_xml or to_json without having to depict the base class data in the serialized string. Here are my classes:
# base class class Asset < ActiveRecord::Base belongs_to :resource, :polymorphic => true has_many :right_owners, :dependent => :destroy end
# derived class class Song < ActiveRecord::Base has_one :asset, :as => :resource, :dependent => :destroy end
# derived class class Film < ActiveRecord::Base has_one :asset, :as => :resource, :dependent => :destroy end
If I instantiate the asset, as in the case of asset = Asset.find (:first, :include=>:resource), I can easily call asset.to_xml (:include=>:right_owners).
However sometimes, we absolutely need to have the concrete class and not just the base class object or serialized state. If I instantiate the song, how can I serialize the underlying asset's right_owners data without introducing the 'asset' as the base class navigational tie? For example: # instantiate the song song = Song.find(:first, :include=>:asset)
# serialize XML or JSON that includes the underlying asset's right_owners # I can do this but this but it is not compatible for our caller since they don't understand the nested base Asset #class song.to_xml(:include=>{:asset=>{:include=>:right_owners}}) #or alternatively for json: song.to_json(:include=>{:asset=>{:include=>:right_owners}})
Is there a way to access and serialize the base class' associative methods, i.e. 'right_owners', without having to include the 'asset' information. That is ideally, I'm looking for <song> <title>.....</title> <artist>.....</artist> <right_owners> <right_owners>....</right_owners> .... </right_owners> </song>
One workaround is to define the right_owners relationship on the Song class but that feels redundant and doesn't follow the DRY principle especially considering there will be other types of derived classes such as Films, etc...
If I define right_owners as a method on the Song class, it just serializes the class name as an array rather treating it as a AR association that I can further navigate. That is a custom method is not being treated the same as the AR association method defined with :has_one or :has_many.
Any insight is much appreciated. Thanks.
