Module: ActionController::Rendering

Extended by:
ActiveSupport::Concern
Included in:
DataStreaming
Defined in:
actionpack/lib/action_controller/metal/rendering.rb

Defined Under Namespace

Modules: ClassMethods

Constant Summary collapse

RENDER_FORMATS_IN_PRIORITY = 
[:body, :plain, :html]

Instance Method Summary collapse

Methods included from ActiveSupport::Concern

append_features, class_methods, extended, included, prepend_features, prepended

Instance Method Details

#render(*args) ⇒ Object

Renders a template and assigns the result to self.response_body.

If no rendering mode option is specified, the template will be derived from the first argument.

render "posts/show"
# => renders app/views/posts/show.html.erb

# In a PostsController action...
render :show
# => renders app/views/posts/show.html.erb

If the first argument responds to render_in, the template will be rendered by calling render_in with the current view context.

Rendering Mode

:partial

See ActionView::PartialRenderer for details.

render partial: "posts/form", locals: { post: Post.new }
# => renders app/views/posts/_form.html.erb
:file

Renders the contents of a file. This option should not be used with unsanitized user input.

render file: "/path/to/some/file"
# => renders /path/to/some/file
:inline

Renders an ERB template string.

@name = "World"
render inline: "<h1>Hello, <%= @name %>!</h1>"
# => renders "<h1>Hello, World!</h1>"
:body

Renders the provided text, and sets the content type as text/plain.

render body: "Hello, World!"
# => renders "Hello, World!"
:plain

Renders the provided text, and sets the content type as text/plain.

render plain: "Hello, World!"
# => renders "Hello, World!"
:html

Renders the provided HTML string, and sets the content type as text/html. If the string is not html_safe?, performs HTML escaping on the string before rendering.

render html: "<h1>Hello, World!</h1>".html_safe
# => renders "<h1>Hello, World!</h1>"

render html: "<h1>Hello, World!</h1>"
# => renders "&lt;h1&gt;Hello, World!&lt;/h1&gt;"
:json

Renders the provided object as JSON, and sets the content type as application/json. If the object is not a string, it will be converted to JSON by calling to_json.

render json: { hello: "world" }
# => renders "{\"hello\":\"world\"}"

By default, when a rendering mode is specified, no layout template is rendered.

Options

:assigns

Hash of instance variable assignments for the template.

render inline: "<h1>Hello, <%= @name %>!</h1>", assigns: { name: "World" }
# => renders "<h1>Hello, World!</h1>"
:locals

Hash of local variable assignments for the template.

render inline: "<h1>Hello, <%= name %>!</h1>", locals: { name: "World" }
# => renders "<h1>Hello, World!</h1>"
:layout

The layout template to render. Can also be false or true to disable or (re)enable the default layout template.

render "posts/show", layout: "holiday"
# => renders app/views/posts/show.html.erb with the app/views/layouts/holiday.html.erb layout

render "posts/show", layout: false
# => renders app/views/posts/show.html.erb with no layout

render inline: "<h1>Hello, World!</h1>", layout: true
# => renders "<h1>Hello, World!</h1>" with the default layout
:status

The HTTP status code to send with the response. Can be specified as a number or as the status name in Symbol form. Defaults to 200.

render "posts/new", status: 422
# => renders app/views/posts/new.html.erb with HTTP status code 422

render "posts/new", status: :unprocessable_entity
# => renders app/views/posts/new.html.erb with HTTP status code 422

– Check for double render errors and set the content_type after rendering.

Raises:



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# File 'actionpack/lib/action_controller/metal/rendering.rb', line 137

def render(*args)
  raise ::AbstractController::DoubleRenderError if response_body
  super
end

#render_to_body(options = {}) ⇒ Object

:nodoc:



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# File 'actionpack/lib/action_controller/metal/rendering.rb', line 157

def render_to_body(options = {}) # :nodoc:
  super || _render_in_priorities(options) || " "
end

#render_to_string ⇒ Object

Similar to #render, but only returns the rendered template as a string, instead of setting self.response_body. – Override render_to_string because body can now be set to a Rack body.



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# File 'actionpack/lib/action_controller/metal/rendering.rb', line 146

def render_to_string(*)
  result = super
  if result.respond_to?(:each)
    string = +""
    result.each { |r| string << r }
    string
  else
    result
  end
end