module ActiveRecord module Integration # Returns a String, which Action Pack uses for constructing an URL to this # object. The default implementation returns this record's id as a String, # or nil if this record's unsaved. # # For example, suppose that you have a User model, and that you have a # resources :users route. Normally, +user_path+ will # construct a path with the user object's 'id' in it: # # user = User.find_by_name('Phusion') # user_path(user) # => "/users/1" # # You can override +to_param+ in your model to make +user_path+ construct # a path using the user's name instead of the user's id: # # class User < ActiveRecord::Base # def to_param # overridden # name # end # end # # user = User.find_by_name('Phusion') # user_path(user) # => "/users/Phusion" def to_param # We can't use alias_method here, because method 'id' optimizes itself on the fly. id && id.to_s # Be sure to stringify the id for routes end # Returns a cache key that can be used to identify this record. # # Product.new.cache_key # => "products/new" # Product.find(5).cache_key # => "products/5" (updated_at not available) # Person.find(5).cache_key # => "people/5-20071224150000" (updated_at available) def cache_key case when new_record? "#{self.class.model_name.cache_key}/new" when timestamp = self[:updated_at] timestamp = timestamp.utc.to_s(:nsec) "#{self.class.model_name.cache_key}/#{id}-#{timestamp}" else "#{self.class.model_name.cache_key}/#{id}" end end end end