Introduction

At this time, action-jackson is an experiment, but I hope that won't be the case for long.

Rails before_filters don't take it far enough. What action-jackson allows you to do is define dependecies between your controller actions and before filters in the same way you do with rake tasks.

Install

Stick this in your GemFile.

gem 'action-jackson'

Usage

Include the DSL

Might as well add it for all you controllers.

class ApplicationController < ActionController::Base
  extend ActionJackson::DSL  
end

Or you can do it on a per controller basis if you insist.

class MyController < ApplicationController
  extend ActionJackson::DSL 
end

Defineing Actions and Filters

Define your actions like this within your controller.

action :index do
end

Important Note: Until I find a better way, you'll also have to add a call to register_filters to the bottom of any class that uses action-jackson. So the above in its entirety might look like this.

class MyController < ApplicationController
  action :index do
  end
  
  register_filters # Don't forget this call. It's Important!
end

Need a before filter? Wire it up like this.

action :index => :load_user do
end

def load_user
  @user = User.find(params[:user_id])
end

which is equivalent to...

before_filter :load_user, :only => :index

def index
end

def load_user
  @user = User.find(params[:user_id])
end

But the fun doesn't stop there. We can define before filters for our before filters.

action :index => :load_user do
end

filter :load_user => :some_other_filter do
end

def some_other_filter
end

As you've probably guessed, filter acts just like action (as a matter of fact it's an alias, well at least for now...).

Lastly, you can also define multiple dependencies with an Array and they'll be executed in the order they appear.

action :index => [:first_filter, :second_filter] do
end

Keep in mind actions can depend on actions, filters can depend on filters, actions on filters, filters on actions, on and on and so forth. The dependency heirarchy can get very deep and complicated, but thanks to action-jackson your code doesn't have to.

Gotchas

If you're using return in your actions you'll want to switch it out with next otherwise you'll receive an error.

def index
  return unless param[:id]
  @item = Item.find(param[:id])
end

becomes...

action :index do
  next unless param[:id]
  @item = Item.find(param[:id])
end