priority_filter
==============

priority_filter is an extension of filters in Rails that allows you to set priorities to filters. The main benefit of 
this is you can now have a filter defined in a parent controller that gets executed after the same type of filter in a 
child controller.

It does this by overriding all the *_filter methods and storing them in an array, and then rebuilding the filter chain 
whenever a filter is added or skipped. This causes a longer loading time, but it only has to do this when the controller 
is loaded, so after the application loads, there is no performance hit (that I can see).

A more elegant solution would to be override the find_filter_append/prepend_position, but it wasn't working for me so I 
gave up and went with this method.

Usage
=====

All the *_filter methods now accept :priority as an option. :priority can be any positive integer, or :first (which gets 
changed to 0) or :last (will always be called after all other filters that are also not :last). Leaving out :priority 
sets the priority to 1. So if you install this plugin into an existing project, it (theoretically) will not change the 
filter execution order. prepend_*_filter simply implies :first.

before_filter :filter, :priority => 5
after_filter :after, :priority => :last


Example
=======

class ApplicationController < ActionController::Base
  before_filter :foo, :priority => 5
  before_filter :bar, :priority => :first
end

class FooController < ApplicationController
  before_filter :rah, :priority => 3
  before_filter :moo, :priority => :first
end

class BarController < FooController
  before_filter :kek
  before_filter :bah, :priority => :last
end

Filter priorities (in execution order):
  :bar => 0
  :moo => 0
  :kek => 1
  :rah => 3
  :foo => 5
  :bah => last
  

Copyright (c) 2008 Jack Chen, under the MIT License