Can I use Struct.new as a Rails model? Or: How to create anonymous structured non-db backed sessions?

Question

Given the following example:

class AnonymousSession << Struct.new(:location, :preferences)
  def valid?
    ...
  end
  def new_record?
    ...
  end
end

While this interface is sufficient to create resourceful form and so on, it fails as soon as I want to save my form data to the session:

if session[:user] = AnonymousSession.create(params[:anonymous_session])
  #--> fails with "unknown key(s): location..."
  ...
end

The error message is about "unknown keys". Any clue how to make it work? I just need anonymous sessions without database backend. They are completely disposable due to their short live nature.

Maybe my approach is wrong anyway and there's already an elegant solution to using anonymous sessions? I had a look at AuthLogic but any example I found always comes with an ActiveRecord model (and thus bound to a database).

Answer 1

I have used this solution, where my model derives from Tableless. I think it will work in your case as well.

Answer 2

You'd have to explain more as to what you're trying to accomplish. Why couldn't you just create an AnonymousSession class in /app/models?

class AnonymousSession

  attr_accessor :location, :preferences

  def new_record?
   # ...
  end

  def valid?
   # ...
  end

end

Answer 3

Ryan Bates has a couple Railscast episodes that might help you out: Session Based Model and Super Simple Authentication.