Ruby on Rails - Access controller variable from model

Question

I am trying to access an instance variable which is set in the controller in the model. The controller is the products controller and the model is the products model. The in

Answer 1

DISCLAIMER: The following code breaks MVC conventions, that said...

Using class attributes can probably lead to thread safety issues. I would use Thread.current + around_filter to store controller related data at thread level, and ensure it gets cleared just before the request finishes:

class ApplicationController < ActionController::Base

  around_filter :wrap_with_hack

  def wrap_with_hack
    # We could do this (greener solution): 
    # http://coderrr.wordpress.com/2008/04/10/lets-stop-polluting-the-threadcurrent-hash/
    # ... but for simplicity sake:
    Thread.current[:controller] = self
    begin
      yield
    ensure
     # Prevent cross request access if thread is reused later
     Thread.current[:controller] = nil
    end
  end
end

Now the current controller instance will be avaliable globaly during the request processing through Thread.current[:controller]