Multiple has_many_polymorphs in one model

I’m trying to define multiple polymorphic relations (`has_many_polymorphs plugin`) from a single parent to same children.

Note has many viewers
Note has many editors
Viewers could be either Users or Groups
Editors could be either Users or Groups
Permission is the association model with `note_id`, `viewer_id`, `viewer_type`, `editor_id`, `editor_type` fields

Everything works out as expect as long as I have only one has_many_polymorphs relation defined in Note model


class User < ActiveRecord::Base; end

class Group < ActiveRecord::Base; end

class Note < ActiveRecord::Base
has_many_polymorphs :viewers, :through => :permissions, :from => [:users, :groups]
end

class Permission < ActiveRecord::Base
belongs_to :note
belongs_to :viewer, :polymorphic => true
end

Now, problems start to appear when I add the second relation


class Note < ActiveRecord::Base
has_many_polymorphs :viewers, :through => :permissions, :from => [:users, :groups]
has_many_polymorphs :editors, :through => :permissions, :from => [:users, :groups]
end

class Permission < ActiveRecord::Base
belongs_to :note
belongs_to :viewer, :polymorphic => true
belongs_to :editor, :polymorphic => true
end

Note.first.viewers << User.first # => [#<User id: ....>]

—-

I’ve tried refining the definition of `has_many_polymorphs` but it didn’t work. Not even with an STI model for `ViewPermission < Permission`, and `EditPermission < Permission`.

Any thoughts / workarounds / issue pointers are appreciated.

Rails 2.3.0

Posted to:

• Stack Overflow (http://stackoverflow.com/questions/983225/multiple-hasmanypolymorphs-in-one-model)
• Github (issue)  (http://github.com/fauna/has_many_polymorphs/issues/#issue/3)