Questions on nested resources in Ruby on Rails

How can I specify a custom action for a nested URL in ruby on rails? For example, I have two resources people and book. In the b开发者_如何学运维ook controller, I have a custom action, say foo_action. I am wonder how can I use nested resources in ruby on rails to specify something like:

people/10/book/foo_action/20

basically, call the foo_action associated with book 20 which belongs to people 10. (people and book are one-to-many relations).

Thanks a lot.

---

map.resources :people do |person|
  person.resources :books, :member => {:foo_action => :get}
end

Replace :get with any method your action should be accessible with (get, post, put or delete).