Class: ActionController::Metal

Inherits:
AbstractController::Base show all
Defined in:
actionpack/lib/action_controller/metal.rb

Overview

ActionController::Metal is the simplest possible controller, providing a valid Rack interface without the additional niceties provided by ActionController::Base.

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 config/routes.rb:

match 'hello', :to => HelloController.action(:index)

The action method returns a valid Rack application for the Rails router to dispatch to.

Rendering Helpers

ActionController::Metal by default provides no utilities for rendering views, partials, or other responses aside from explicitly calling of response_body=, content_type=, and status=. 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 ActionController::Base to see other features you can bring into your metal controller.

Direct Known Subclasses

Base, Middleware

Class Method Summary collapse

Instance Method Summary collapse

Methods inherited from AbstractController::Base

abstract!, #action_methods, action_methods, #available_action?, clear_action_methods!, #controller_path, controller_path, hidden_actions, internal_methods, method_added, #process

Methods included from ActiveSupport::DescendantsTracker

clear, #descendants, descendants, #direct_descendants, direct_descendants, #inherited

Methods included from ActiveSupport::Configurable

#config

Methods included from ActiveSupport::Concern

#append_features, extended, #included

Constructor Details

#initializeMetal


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# File 'actionpack/lib/action_controller/metal.rb', line 134

def initialize
  @_headers = {"Content-Type" => "text/html"}
  @_status = 200
  @_request = nil
  @_response = nil
  @_routes = nil
  super
end

Class Method Details

.action(name, klass = ActionDispatch::Request) ⇒ Object

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 - An action name

Returns

  • proc - A rack application


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# File 'actionpack/lib/action_controller/metal.rb', line 244

def self.action(name, klass = ActionDispatch::Request)
  middleware_stack.build(name.to_s) do |env|
    new.dispatch(name, klass.new(env))
  end
end

.call(env) ⇒ Object

Makes the controller a rack endpoint that points to the action in the given env's action_dispatch.request.path_parameters key.


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# File 'actionpack/lib/action_controller/metal.rb', line 231

def self.call(env)
  action(env['action_dispatch.request.path_parameters'][:action]).call(env)
end

.controller_nameObject

Returns the last part of the controller's name, underscored, without the ending Controller. For instance, PostsController returns posts. Namespaces are left out, so Admin::PostsController returns posts as well.

Returns

  • string


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# File 'actionpack/lib/action_controller/metal.rb', line 116

def self.controller_name
  @controller_name ||= self.name.demodulize.sub(/Controller$/, '').underscore
end

.inherited(base) ⇒ Object

nodoc:


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# File 'actionpack/lib/action_controller/metal.rb', line 214

def self.inherited(base) #nodoc:
  base.middleware_stack = self.middleware_stack.dup
  super
end

.middlewareObject

Alias for middleware_stack


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# File 'actionpack/lib/action_controller/metal.rb', line 225

def self.middleware
  middleware_stack
end

.use(*args, &block) ⇒ Object

Adds given middleware class and its args to bottom of middleware_stack


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# File 'actionpack/lib/action_controller/metal.rb', line 220

def self.use(*args, &block)
  middleware_stack.use(*args, &block)
end

Instance Method Details

#content_typeObject


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# File 'actionpack/lib/action_controller/metal.rb', line 159

def content_type
  headers["Content-Type"]
end

#content_type=(type) ⇒ Object

Basic implementations for content_type=, location=, and headers are provided to reduce the dependency on the RackDelegation module in Renderer and Redirector.


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# File 'actionpack/lib/action_controller/metal.rb', line 155

def content_type=(type)
  headers["Content-Type"] = type.to_s
end

#controller_nameObject

Delegates to the class' controller_name


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# File 'actionpack/lib/action_controller/metal.rb', line 121

def controller_name
  self.class.controller_name
end

#dispatch(name, request) ⇒ Object

:nodoc:


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# File 'actionpack/lib/action_controller/metal.rb', line 199

def dispatch(name, request) #:nodoc:
  @_request = request
  @_env = request.env
  @_env['action_controller.instance'] = self
  process(name)
  to_a
end

#envObject


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# File 'actionpack/lib/action_controller/metal.rb', line 106

def env
  @_env ||= {}
end

#locationObject


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# File 'actionpack/lib/action_controller/metal.rb', line 163

def location
  headers["Location"]
end

#location=(url) ⇒ Object


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# File 'actionpack/lib/action_controller/metal.rb', line 167

def location=(url)
  headers["Location"] = url
end

#paramsObject


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# File 'actionpack/lib/action_controller/metal.rb', line 143

def params
  @_params ||= request.parameters
end

#params=(val) ⇒ Object


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# File 'actionpack/lib/action_controller/metal.rb', line 147

def params=(val)
  @_params = val
end

#performed?Boolean


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# File 'actionpack/lib/action_controller/metal.rb', line 195

def performed?
  response_body
end

#response_body=(val) ⇒ Object


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# File 'actionpack/lib/action_controller/metal.rb', line 184

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

#statusObject


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# File 'actionpack/lib/action_controller/metal.rb', line 176

def status
  @_status
end

#status=(status) ⇒ Object


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# File 'actionpack/lib/action_controller/metal.rb', line 180

def status=(status)
  @_status = Rack::Utils.status_code(status)
end

#to_aObject

:nodoc:


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# File 'actionpack/lib/action_controller/metal.rb', line 207

def to_a #:nodoc:
  response ? response.to_a : [status, headers, response_body]
end

#url_for(string) ⇒ Object

basic url_for that can be overridden for more robust functionality


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# File 'actionpack/lib/action_controller/metal.rb', line 172

def url_for(string)
  string
end