Skip to Content Skip to Search

Action Controller Renderer

ActionController::Renderer allows you to render arbitrary templates without being inside a controller action.

You can get a renderer instance by calling renderer on a controller class:

ApplicationController.renderer
PostsController.renderer

and render a template by calling the render method:

ApplicationController.renderer.render template: "posts/show", assigns: { post: Post.first }
PostsController.renderer.render :show, assigns: { post: Post.first }

As a shortcut, you can also call render directly on the controller class itself:

ApplicationController.render template: "posts/show", assigns: { post: Post.first }
PostsController.render :show, assigns: { post: Post.first }
Methods
D
F
N
R
W

Constants

DEFAULTS = { method: "get", input: "" }.freeze
 
RACK_KEY_TRANSLATION = { http_host: "HTTP_HOST", https: "HTTPS", method: "REQUEST_METHOD", script_name: "SCRIPT_NAME", input: "rack.input" }
 

Attributes

[R] controller

Class Public methods

for(controller, env = nil, defaults = DEFAULTS)

Creates a new renderer using the given controller class. See ::new.

Source: show | on GitHub 

# File actionpack/lib/action_controller/renderer.rb, line 64
def self.for(controller, env = nil, defaults = DEFAULTS)
  new(controller, env, defaults)
end

new(controller, env, defaults)

Initializes a new Renderer.

Parameters

  • controller - The controller class to instantiate for rendering.

  • env - The Rack env to use for mocking a request when rendering. Entries can be typical Rack env keys and values, or they can be any of the following, which will be converted appropriately:

    • :http_host - The HTTP host for the incoming request. Converts to Rack’s HTTP_HOST.

    • :https - Boolean indicating whether the incoming request uses HTTPS. Converts to Rack’s HTTPS.

    • :method - The HTTP method for the incoming request, case-insensitive. Converts to Rack’s REQUEST_METHOD.

    • :script_name - The portion of the incoming request’s URL path that corresponds to the application. Converts to Rack’s SCRIPT_NAME.

    • :input - The input stream. Converts to Rack’s rack.input.

    • :http_host - The HTTP host for the incoming request. Converts to Rack’s HTTP_HOST.

    • :https - Boolean indicating whether the incoming request uses HTTPS. Converts to Rack’s HTTPS.

    • :method - The HTTP method for the incoming request, case-insensitive. Converts to Rack’s REQUEST_METHOD.

    • :script_name - The portion of the incoming request’s URL path that corresponds to the application. Converts to Rack’s SCRIPT_NAME.

    • :input - The input stream. Converts to Rack’s rack.input.

  • defaults - Default values for the Rack env. Entries are specified in the same format as env. env will be merged on top of these values. defaults will be retained when calling new on a renderer instance.

If no http_host is specified, the env HTTP host will be derived from the routes’ default_url_options. In this case, the https boolean and the script_name will also be derived from default_url_options if they were not specified. Additionally, the https boolean will fall back to Rails.application.config.force_ssl if default_url_options does not specify a protocol.

Source: show | on GitHub 

# File actionpack/lib/action_controller/renderer.rb, line 111
def initialize(controller, env, defaults)
  @controller = controller
  @defaults = defaults
  if env.blank? && @defaults == DEFAULTS
    @env = DEFAULT_ENV
  else
    @env = normalize_env(@defaults)
    @env.merge!(normalize_env(env)) unless env.blank?
  end
end

Instance Public methods

defaults()

Source: show | on GitHub 

# File actionpack/lib/action_controller/renderer.rb, line 122
def defaults
  @defaults = @defaults.dup if @defaults.frozen?
  @defaults
end

new(env = nil)

Creates a new renderer using the same controller, but with a new Rack env.

ApplicationController.renderer.new(method: "post")

Source: show | on GitHub 

# File actionpack/lib/action_controller/renderer.rb, line 72
def new(env = nil)
  self.class.new controller, env, @defaults
end

render(*args)

Renders a template to a string, just like ActionController::Rendering#render_to_string.

Source: show | on GitHub 

# File actionpack/lib/action_controller/renderer.rb, line 129
def render(*args)
  request = ActionDispatch::Request.new(env_for_request)
  request.routes = controller._routes

  instance = controller.new
  instance.set_request! request
  instance.set_response! controller.make_response!(request)
  instance.render_to_string(*args)
end

with_defaults(defaults)

Creates a new renderer using the same controller, but with the given defaults merged on top of the previous defaults.

Source: show | on GitHub 

# File actionpack/lib/action_controller/renderer.rb, line 78
def with_defaults(defaults)
  self.class.new controller, @env, @defaults.merge(defaults)
end