session in the model

Hello,

I needed a couple of session variables to allow a reader of a blog to
be redirected to the correct URL if the blog name he's visiting
(app/:blogname) gets updated;
Question: is it convenient to pass 'base' to the model or would it be
more efficient to do everything in the controller?

ex. in blog.rb

  def self.locate(base)
    if !base.session[:last_visited_blog_id].nil? && base.params[:blog]
== base.session[:last_visited_blog_seo]
      return Blog.find_by_id(base.session[:last_visited_blog_id])
    end
  end

thanks!

redirection and related stuff is handled inside your controllers.