diff options
Diffstat (limited to 'actionpack/lib/action_controller/metal.rb')
| -rw-r--r-- | actionpack/lib/action_controller/metal.rb | 256 |
1 files changed, 256 insertions, 0 deletions
diff --git a/actionpack/lib/action_controller/metal.rb b/actionpack/lib/action_controller/metal.rb new file mode 100644 index 0000000000..f875aa5e6b --- /dev/null +++ b/actionpack/lib/action_controller/metal.rb @@ -0,0 +1,256 @@ +# frozen_string_literal: true + +require "active_support/core_ext/array/extract_options" +require "action_dispatch/middleware/stack" +require "action_dispatch/http/request" +require "action_dispatch/http/response" + +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, actions, strategy, block) + @actions = actions + @strategy = strategy + super(klass, args, block) + end + + def valid?(action) + @strategy.call @actions, action + end + end + + def build(action, app = Proc.new) + action = action.to_s + + middlewares.reverse.inject(app) do |a, middleware| + middleware.valid?(action) ? middleware.build(a) : a + end + end + + private + + INCLUDE = ->(list, action) { list.include? action } + EXCLUDE = ->(list, action) { !list.include? action } + NULL = ->(list, action) { true } + + def build_middleware(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? + + strategy = NULL + list = nil + + if only.any? + strategy = INCLUDE + list = only + elsif except.any? + strategy = EXCLUDE + list = except + end + + Middleware.new(klass, args, list, strategy, block) + 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>: + # + # get '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 AbstractController::Rendering + # include ActionView::Layouts + # 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! + + # 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 ||= name.demodulize.sub(/Controller$/, "").underscore + end + + def self.make_response!(request) + ActionDispatch::Response.new.tap do |res| + res.request = request + end + end + + def self.binary_params_for?(action) # :nodoc: + false + end + + # Delegates to the class' <tt>controller_name</tt>. + def controller_name + self.class.controller_name + end + + attr_internal :response, :request + delegate :session, to: "@_request" + delegate :headers, :status=, :location=, :content_type=, + :status, :location, :content_type, to: "@_response" + + def initialize + @_request = nil + @_response = nil + @_routes = nil + super + end + + def params + @_params ||= request.parameters + end + + def params=(val) + @_params = val + end + + alias :response_code :status # :nodoc: + + # Basic url_for that can be overridden for more robust functionality. + def url_for(string) + string + end + + def response_body=(body) + body = [body] unless body.nil? || body.respond_to?(:each) + response.reset_body! + return unless body + response.body = body + super + end + + # Tests if render or redirect has already happened. + def performed? + response_body || response.committed? + end + + def dispatch(name, request, response) #:nodoc: + set_request!(request) + set_response!(response) + process(name) + request.commit_flash + to_a + end + + def set_response!(response) # :nodoc: + @_response = response + end + + def set_request!(request) #:nodoc: + @_request = request + @_request.controller_instance = self + end + + def to_a #:nodoc: + response.to_a + end + + def reset_session + @_request.reset_session + end + + class_attribute :middleware_stack, default: ActionController::MiddlewareStack.new + + def self.inherited(base) # :nodoc: + base.middleware_stack = middleware_stack.dup + super + end + + # Pushes the given Rack middleware and its arguments to the bottom of the + # middleware stack. + def self.use(*args, &block) + middleware_stack.use(*args, &block) + end + + # Alias for +middleware_stack+. + def self.middleware + middleware_stack + end + + # Returns a Rack endpoint for the given action name. + def self.action(name) + app = lambda { |env| + req = ActionDispatch::Request.new(env) + res = make_response! req + new.dispatch(name, req, res) + } + + if middleware_stack.any? + middleware_stack.build(name, app) + else + app + end + end + + # Direct dispatch to the controller. Instantiates the controller, then + # executes the action named +name+. + def self.dispatch(name, req, res) + if middleware_stack.any? + middleware_stack.build(name) { |env| new.dispatch(name, req, res) }.call req.env + else + new.dispatch(name, req, res) + end + end + end +end |