require 'active_support/core_ext/class/attribute'
module ActionController
# ActionController::Metal provides a way to get a valid Rack application from a controller.
#
# In AbstractController, dispatching is triggered directly by calling #process on a new controller.
# ActionController::Metal provides an #action method that returns a valid Rack application for a
# given action. Other rack builders, such as Rack::Builder, Rack::URLMap, and the Rails router,
# can dispatch directly to the action returned by FooController.action(:index).
class Metal < AbstractController::Base
abstract!
# :api: public
attr_internal :params, :env
# Returns the last part of the controller's name, underscored, without the ending
# "Controller". For instance, MyApp::MyPostsController would return "my_posts" for
# controller_name
#
# ==== Returns
# String
def self.controller_name
@controller_name ||= controller_path.split("/").last
end
# Delegates to the class' #controller_name
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 :status, :headers, :content_type, :response
def initialize(*)
@_headers = {}
super
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
def status=(status)
@_status = Rack::Utils.status_code(status)
end
# :api: private
def dispatch(name, env)
@_env = env
@_env['action_controller.instance'] = self
process(name)
to_a
end
# :api: private
def to_a
response ? response.to_a : [status, headers, response_body]
end
class ActionEndpoint
@@endpoints = Hash.new {|h,k| h[k] = Hash.new {|sh,sk| sh[sk] = {} } }
def self.for(controller, action, stack)
@@endpoints[controller][action][stack] ||= begin
endpoint = new(controller, action)
stack.build(endpoint)
end
end
def initialize(controller, action)
@controller, @action = controller, action
@_formats = [Mime::HTML]
end
def call(env)
@controller.new.dispatch(@action, env)
end
end
class_attribute :middleware_stack
self.middleware_stack = ActionDispatch::MiddlewareStack.new
def self.inherited(base)
self.middleware_stack = base.middleware_stack.dup
end
def self.use(*args)
middleware_stack.use(*args)
end
def self.middleware
middleware_stack
end
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
# action<#to_s>:: An action name
#
# ==== Returns
# Proc:: A rack application
def self.action(name)
ActionEndpoint.for(self, name, middleware_stack)
end
end
end
