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Diffstat (limited to 'actionpack/lib/action_controller/metal/renderers.rb')
| -rw-r--r-- | actionpack/lib/action_controller/metal/renderers.rb | 181 |
1 files changed, 181 insertions, 0 deletions
diff --git a/actionpack/lib/action_controller/metal/renderers.rb b/actionpack/lib/action_controller/metal/renderers.rb new file mode 100644 index 0000000000..b81d3ef539 --- /dev/null +++ b/actionpack/lib/action_controller/metal/renderers.rb @@ -0,0 +1,181 @@ +# frozen_string_literal: true + +require "set" + +module ActionController + # See <tt>Renderers.add</tt> + def self.add_renderer(key, &block) + Renderers.add(key, &block) + end + + # See <tt>Renderers.remove</tt> + def self.remove_renderer(key) + Renderers.remove(key) + end + + # See <tt>Responder#api_behavior</tt> + class MissingRenderer < LoadError + def initialize(format) + super "No renderer defined for format: #{format}" + end + end + + module Renderers + extend ActiveSupport::Concern + + # A Set containing renderer names that correspond to available renderer procs. + # Default values are <tt>:json</tt>, <tt>:js</tt>, <tt>:xml</tt>. + RENDERERS = Set.new + + included do + class_attribute :_renderers, default: Set.new.freeze + end + + # Used in <tt>ActionController::Base</tt> + # and <tt>ActionController::API</tt> to include all + # renderers by default. + module All + extend ActiveSupport::Concern + include Renderers + + included do + self._renderers = RENDERERS + end + end + + # Adds a new renderer to call within controller actions. + # A renderer is invoked by passing its name as an option to + # <tt>AbstractController::Rendering#render</tt>. To create a renderer + # pass it a name and a block. The block takes two arguments, the first + # is the value paired with its key and the second is the remaining + # hash of options passed to +render+. + # + # Create a csv renderer: + # + # ActionController::Renderers.add :csv do |obj, options| + # filename = options[:filename] || 'data' + # str = obj.respond_to?(:to_csv) ? obj.to_csv : obj.to_s + # send_data str, type: Mime[:csv], + # disposition: "attachment; filename=#{filename}.csv" + # end + # + # Note that we used Mime[:csv] for the csv mime type as it comes with Rails. + # For a custom renderer, you'll need to register a mime type with + # <tt>Mime::Type.register</tt>. + # + # To use the csv renderer in a controller action: + # + # def show + # @csvable = Csvable.find(params[:id]) + # respond_to do |format| + # format.html + # format.csv { render csv: @csvable, filename: @csvable.name } + # end + # end + def self.add(key, &block) + define_method(_render_with_renderer_method_name(key), &block) + RENDERERS << key.to_sym + end + + # This method is the opposite of add method. + # + # To remove a csv renderer: + # + # ActionController::Renderers.remove(:csv) + def self.remove(key) + RENDERERS.delete(key.to_sym) + method_name = _render_with_renderer_method_name(key) + remove_possible_method(method_name) + end + + def self._render_with_renderer_method_name(key) + "_render_with_renderer_#{key}" + end + + module ClassMethods + # Adds, by name, a renderer or renderers to the +_renderers+ available + # to call within controller actions. + # + # It is useful when rendering from an <tt>ActionController::Metal</tt> controller or + # otherwise to add an available renderer proc to a specific controller. + # + # Both <tt>ActionController::Base</tt> and <tt>ActionController::API</tt> + # include <tt>ActionController::Renderers::All</tt>, making all renderers + # available in the controller. See <tt>Renderers::RENDERERS</tt> and <tt>Renderers.add</tt>. + # + # Since <tt>ActionController::Metal</tt> controllers cannot render, the controller + # must include <tt>AbstractController::Rendering</tt>, <tt>ActionController::Rendering</tt>, + # and <tt>ActionController::Renderers</tt>, and have at least one renderer. + # + # Rather than including <tt>ActionController::Renderers::All</tt> and including all renderers, + # you may specify which renderers to include by passing the renderer name or names to + # +use_renderers+. For example, a controller that includes only the <tt>:json</tt> renderer + # (+_render_with_renderer_json+) might look like: + # + # class MetalRenderingController < ActionController::Metal + # include AbstractController::Rendering + # include ActionController::Rendering + # include ActionController::Renderers + # + # use_renderers :json + # + # def show + # render json: record + # end + # end + # + # You must specify a +use_renderer+, else the +controller.renderer+ and + # +controller._renderers+ will be <tt>nil</tt>, and the action will fail. + def use_renderers(*args) + renderers = _renderers + args + self._renderers = renderers.freeze + end + alias use_renderer use_renderers + end + + # Called by +render+ in <tt>AbstractController::Rendering</tt> + # which sets the return value as the +response_body+. + # + # If no renderer is found, +super+ returns control to + # <tt>ActionView::Rendering.render_to_body</tt>, if present. + def render_to_body(options) + _render_to_body_with_renderer(options) || super + end + + def _render_to_body_with_renderer(options) + _renderers.each do |name| + if options.key?(name) + _process_options(options) + method_name = Renderers._render_with_renderer_method_name(name) + return send(method_name, options.delete(name), options) + end + end + nil + end + + add :json do |json, options| + json = json.to_json(options) unless json.kind_of?(String) + + if options[:callback].present? + if content_type.nil? || content_type == Mime[:json] + self.content_type = Mime[:js] + end + + "/**/#{options[:callback]}(#{json})" + else + self.content_type ||= Mime[:json] + json + end + end + + add :js do |js, options| + self.content_type ||= Mime[:js] + js.respond_to?(:to_js) ? js.to_js(options) : js + end + + add :xml do |xml, options| + self.content_type ||= Mime[:xml] + xml.respond_to?(:to_xml) ? xml.to_xml(options) : xml + end + end +end |