require 'active_support/core_ext/class/attribute'
require 'active_support/core_ext/object/blank'
require 'action_dispatch/middleware/stack'
module ActionController
# Extend ActionDispatch middleware stack to make it aware of options
# allowing the following syntax in controllers:
#
# class PostsController < ApplicationController
# use AuthenticationMiddleware, :except => [:index, :show]
# end
#
class MiddlewareStack < ActionDispatch::MiddlewareStack #:nodoc:
class Middleware < ActionDispatch::MiddlewareStack::Middleware #:nodoc:
def initialize(klass, *args, &block)
options = args.extract_options!
@only = Array(options.delete(:only)).map(&:to_s)
@except = Array(options.delete(:except)).map(&:to_s)
args << options unless options.empty?
super
end
def valid?(action)
if @only.present?
@only.include?(action)
elsif @except.present?
!@except.include?(action)
else
true
end
end
end
def build(action, app=nil, &block)
app ||= block
action = action.to_s
raise "MiddlewareStack#build requires an app" unless app
middlewares.reverse.inject(app) do |a, middleware|
middleware.valid?(action) ?
middleware.build(a) : a
end
end
end
# <tt>ActionController::Metal</tt> is the simplest possible controller, providing a
# valid Rack interface without the additional niceties provided by
# <tt>ActionController::Base</tt>.
#
# A sample metal controller might look like this:
#
# class HelloController < ActionController::Metal
# def index
# self.response_body = "Hello World!"
# end
# end
#
# And then to route requests to your metal controller, you would add
# something like this to <tt>config/routes.rb</tt>:
#
# match 'hello', :to => HelloController.action(:index)
#
# The +action+ method returns a valid Rack application for the \Rails
# router to dispatch to.
#
# == Rendering Helpers
#
# <tt>ActionController::Metal</tt> by default provides no utilities for rendering
# views, partials, or other responses aside from explicitly calling of
# <tt>response_body=</tt>, <tt>content_type=</tt>, and <tt>status=</tt>. To
# add the render helpers you're used to having in a normal controller, you
# can do the following:
#
# class HelloController < ActionController::Metal
# include ActionController::Rendering
# append_view_path "#{Rails.root}/app/views"
#
# def index
# render "hello/index"
# end
# end
#
# == Redirection Helpers
#
# To add redirection helpers to your metal controller, do the following:
#
# class HelloController < ActionController::Metal
# include ActionController::Redirecting
# include Rails.application.routes.url_helpers
#
# def index
# redirect_to root_url
# end
# end
#
# == Other Helpers
#
# You can refer to the modules included in <tt>ActionController::Base</tt> to see
# other features you can bring into your metal controller.
#
class Metal < AbstractController::Base
abstract!
attr_internal_writer :env
def env
@_env ||= {}
end
# Returns the last part of the controller's name, underscored, without the ending
# <tt>Controller</tt>. For instance, PostsController returns <tt>posts</tt>.
# Namespaces are left out, so Admin::PostsController returns <tt>posts</tt> as well.
#
# ==== Returns
# * <tt>string</tt>
def self.controller_name
@controller_name ||= self.name.demodulize.sub(/Controller$/, '').underscore
end
# Delegates to the class' <tt>controller_name</tt>
def controller_name
self.class.controller_name
end
# The details below can be overridden to support a specific
# Request and Response object. The default ActionController::Base
# implementation includes RackDelegation, which makes a request
# and response object available. You might wish to control the
# environment and response manually for performance reasons.
attr_internal :headers, :response, :request
delegate :session, :to => "@_request"
def initialize
@_headers = {"Content-Type" => "text/html"}
@_status = 200
@_request = nil
@_response = nil
@_routes = nil
super
end
def params
@_params ||= request.parameters
end
def params=(val)
@_params = val
end
# Basic implementations for content_type=, location=, and headers are
# provided to reduce the dependency on the RackDelegation module
# in Renderer and Redirector.
def content_type=(type)
headers["Content-Type"] = type.to_s
end
def content_type
headers["Content-Type"]
end
def location
headers["Location"]
end
def location=(url)
headers["Location"] = url
end
# basic url_for that can be overridden for more robust functionality
def url_for(string)
string
end
def status
@_status
end
def status=(status)
@_status = Rack::Utils.status_code(status)
end
def response_body=(val)
body = if val.is_a?(String)
[val]
elsif val.nil? || val.respond_to?(:each)
val
else
[val]
end
super body
end
def dispatch(name, request) #:nodoc:
@_request = request
@_env = request.env
@_env['action_controller.instance'] = self
process(name)
to_a
end
def to_a #:nodoc:
response ? response.to_a : [status, headers, response_body]
end
class_attribute :middleware_stack
self.middleware_stack = ActionController::MiddlewareStack.new
def self.inherited(base) #nodoc:
base.middleware_stack = self.middleware_stack.dup
super
end
# Adds given middleware class and its args to bottom of middleware_stack
def self.use(*args, &block)
middleware_stack.use(*args, &block)
end
# Alias for middleware_stack
def self.middleware
middleware_stack
end
# Makes the controller a rack endpoint that points to the action in
# the given env's action_dispatch.request.path_parameters key.
def self.call(env)
action(env['action_dispatch.request.path_parameters'][:action]).call(env)
end
# Return a rack endpoint for the given action. Memoize the endpoint, so
# multiple calls into MyController.action will return the same object
# for the same action.
#
# ==== Parameters
# * <tt>action</tt> - An action name
#
# ==== Returns
# * <tt>proc</tt> - A rack application
def self.action(name, klass = ActionDispatch::Request)
middleware_stack.build(name.to_s) do |env|
new.dispatch(name, klass.new(env))
end
end
end
end
