Move respond_with to the responders gem

respond_with (and consequently the class-level respond_to)
are being removed from Rails. Instead of moving it to a 3rd
library, the functionality will be moved to responders gem
(at github.com/plataformatec/responders) which already provides
some responders extensions.

2 files changed, 3 insertions, 528 deletions

diff --git a/actionpack/lib/action_controller/metal/mime_responds.rb b/actionpack/lib/action_controller/metal/mime_responds.rb
index 00e7e980f8..a533f03b6d 100644
--- a/actionpack/lib/action_controller/metal/mime_responds.rb
+++ b/actionpack/lib/action_controller/metal/mime_responds.rb
@@ -5,58 +5,6 @@ module ActionController #:nodoc:
   module MimeResponds
     extend ActiveSupport::Concern
 
-    included do
-      class_attribute :responder, :mimes_for_respond_to
-      self.responder = ActionController::Responder
-      clear_respond_to
-    end
-
-    module ClassMethods
-      # Defines mime types that are rendered by default when invoking
-      # <tt>respond_with</tt>.
-      #
-      #   respond_to :html, :xml, :json
-      #
-      # Specifies that all actions in the controller respond to requests
-      # for <tt>:html</tt>, <tt>:xml</tt> and <tt>:json</tt>.
-      #
-      # To specify on per-action basis, use <tt>:only</tt> and
-      # <tt>:except</tt> with an array of actions or a single action:
-      #
-      #   respond_to :html
-      #   respond_to :xml, :json, except: [ :edit ]
-      #
-      # This specifies that all actions respond to <tt>:html</tt>
-      # and all actions except <tt>:edit</tt> respond to <tt>:xml</tt> and
-      # <tt>:json</tt>.
-      #
-      #   respond_to :json, only: :create
-      #
-      # This specifies that the <tt>:create</tt> action and no other responds
-      # to <tt>:json</tt>.
-      def respond_to(*mimes)
-        options = mimes.extract_options!
-
-        only_actions   = Array(options.delete(:only)).map(&:to_s)
-        except_actions = Array(options.delete(:except)).map(&:to_s)
-
-        new = mimes_for_respond_to.dup
-        mimes.each do |mime|
-          mime = mime.to_sym
-          new[mime]          = {}
-          new[mime][:only]   = only_actions   unless only_actions.empty?
-          new[mime][:except] = except_actions unless except_actions.empty?
-        end
-        self.mimes_for_respond_to = new.freeze
-      end
-
-      # Clear all mime types in <tt>respond_to</tt>.
-      #
-      def clear_respond_to
-        self.mimes_for_respond_to = Hash.new.freeze
-      end
-    end
-
     # Without web-service support, an action which collects the data for displaying a list of people
     # might look something like this:
     #
@@ -253,189 +201,13 @@ module ActionController #:nodoc:
     def respond_to(*mimes, &block)
       raise ArgumentError, "respond_to takes either types or a block, never both" if mimes.any? && block_given?
 
-      if collector = retrieve_collector_from_mimes(mimes, &block)
-        response = collector.response
-        response ? response.call : render({})
-      end
-    end
-
-    # For a given controller action, respond_with generates an appropriate
-    # response based on the mime-type requested by the client.
-    #
-    # If the method is called with just a resource, as in this example -
-    #
-    #   class PeopleController < ApplicationController
-    #     respond_to :html, :xml, :json
-    #
-    #     def index
-    #       @people = Person.all
-    #       respond_with @people
-    #     end
-    #   end
-    #
-    # then the mime-type of the response is typically selected based on the
-    # request's Accept header and the set of available formats declared
-    # by previous calls to the controller's class method +respond_to+. Alternatively
-    # the mime-type can be selected by explicitly setting <tt>request.format</tt> in
-    # the controller.
-    #
-    # If an acceptable format is not identified, the application returns a
-    # '406 - not acceptable' status. Otherwise, the default response is to render
-    # a template named after the current action and the selected format,
-    # e.g. <tt>index.html.erb</tt>. If no template is available, the behavior
-    # depends on the selected format:
-    #
-    # * for an html response - if the request method is +get+, an exception
-    #   is raised but for other requests such as +post+ the response
-    #   depends on whether the resource has any validation errors (i.e.
-    #   assuming that an attempt has been made to save the resource,
-    #   e.g. by a +create+ action) -
-    #   1. If there are no errors, i.e. the resource
-    #      was saved successfully, the response +redirect+'s to the resource
-    #      i.e. its +show+ action.
-    #   2. If there are validation errors, the response
-    #      renders a default action, which is <tt>:new</tt> for a
-    #      +post+ request or <tt>:edit</tt> for +patch+ or +put+.
-    #   Thus an example like this -
-    #
-    #     respond_to :html, :xml
-    #
-    #     def create
-    #       @user = User.new(params[:user])
-    #       flash[:notice] = 'User was successfully created.' if @user.save
-    #       respond_with(@user)
-    #     end
-    #
-    #   is equivalent, in the absence of <tt>create.html.erb</tt>, to -
-    #
-    #     def create
-    #       @user = User.new(params[:user])
-    #       respond_to do |format|
-    #         if @user.save
-    #           flash[:notice] = 'User was successfully created.'
-    #           format.html { redirect_to(@user) }
-    #           format.xml { render xml: @user }
-    #         else
-    #           format.html { render action: "new" }
-    #           format.xml { render xml: @user }
-    #         end
-    #       end
-    #     end
-    #
-    # * for a JavaScript request - if the template isn't found, an exception is
-    #   raised.
-    # * for other requests - i.e. data formats such as xml, json, csv etc, if
-    #   the resource passed to +respond_with+ responds to <code>to_<format></code>,
-    #   the method attempts to render the resource in the requested format
-    #   directly, e.g. for an xml request, the response is equivalent to calling
-    #   <code>render xml: resource</code>.
-    #
-    # === Nested resources
-    #
-    # As outlined above, the +resources+ argument passed to +respond_with+
-    # can play two roles. It can be used to generate the redirect url
-    # for successful html requests (e.g. for +create+ actions when
-    # no template exists), while for formats other than html and JavaScript
-    # it is the object that gets rendered, by being converted directly to the
-    # required format (again assuming no template exists).
-    #
-    # For redirecting successful html requests, +respond_with+ also supports
-    # the use of nested resources, which are supplied in the same way as
-    # in <code>form_for</code> and <code>polymorphic_url</code>. For example -
-    #
-    #   def create
-    #     @project = Project.find(params[:project_id])
-    #     @task = @project.comments.build(params[:task])
-    #     flash[:notice] = 'Task was successfully created.' if @task.save
-    #     respond_with(@project, @task)
-    #   end
-    #
-    # This would cause +respond_with+ to redirect to <code>project_task_url</code>
-    # instead of <code>task_url</code>. For request formats other than html or
-    # JavaScript, if multiple resources are passed in this way, it is the last
-    # one specified that is rendered.
-    #
-    # === Customizing response behavior
-    #
-    # Like +respond_to+, +respond_with+ may also be called with a block that
-    # can be used to overwrite any of the default responses, e.g. -
-    #
-    #   def create
-    #     @user = User.new(params[:user])
-    #     flash[:notice] = "User was successfully created." if @user.save
-    #
-    #     respond_with(@user) do |format|
-    #       format.html { render }
-    #     end
-    #   end
-    #
-    # The argument passed to the block is an ActionController::MimeResponds::Collector
-    # object which stores the responses for the formats defined within the
-    # block. Note that formats with responses defined explicitly in this way
-    # do not have to first be declared using the class method +respond_to+.
-    #
-    # Also, a hash passed to +respond_with+ immediately after the specified
-    # resource(s) is interpreted as a set of options relevant to all
-    # formats. Any option accepted by +render+ can be used, e.g.
-    #   respond_with @people, status: 200
-    # However, note that these options are ignored after an unsuccessful attempt
-    # to save a resource, e.g. when automatically rendering <tt>:new</tt>
-    # after a post request.
-    #
-    # Two additional options are relevant specifically to +respond_with+ -
-    # 1. <tt>:location</tt> - overwrites the default redirect location used after
-    #    a successful html +post+ request.
-    # 2. <tt>:action</tt> - overwrites the default render action used after an
-    #    unsuccessful html +post+ request.
-    def respond_with(*resources, &block)
-      if self.class.mimes_for_respond_to.empty?
-        raise "In order to use respond_with, first you need to declare the " \
-          "formats your controller responds to in the class level."
-      end
-
-      if collector = retrieve_collector_from_mimes(&block)
-        options = resources.size == 1 ? {} : resources.extract_options!
-        options = options.clone
-        options[:default_response] = collector.response
-        (options.delete(:responder) || self.class.responder).call(self, resources, options)
-      end
-    end
-
-  protected
-
-    # Collect mimes declared in the class method respond_to valid for the
-    # current action.
-    def collect_mimes_from_class_level #:nodoc:
-      action = action_name.to_s
-
-      self.class.mimes_for_respond_to.keys.select do |mime|
-        config = self.class.mimes_for_respond_to[mime]
-
-        if config[:except]
-          !config[:except].include?(action)
-        elsif config[:only]
-          config[:only].include?(action)
-        else
-          true
-        end
-      end
-    end
-
-    # Returns a Collector object containing the appropriate mime-type response
-    # for the current request, based on the available responses defined by a block.
-    # In typical usage this is the block passed to +respond_with+ or +respond_to+.
-    #
-    # Sends :not_acceptable to the client and returns nil if no suitable format
-    # is available.
-    def retrieve_collector_from_mimes(mimes=nil, &block) #:nodoc:
-      mimes ||= collect_mimes_from_class_level
       collector = Collector.new(mimes, request.variant)
       block.call(collector) if block_given?
-      format = collector.negotiate_format(request)
 
-      if format
+      if format = collector.negotiate_format(request)
         _process_format(format)
-        collector
+        response = collector.response
+        response ? response.call : render({})
       else
         raise ActionController::UnknownFormat
       end
diff --git a/actionpack/lib/action_controller/metal/responder.rb b/actionpack/lib/action_controller/metal/responder.rb
deleted file mode 100644
index 5096558c67..0000000000
--- a/actionpack/lib/action_controller/metal/responder.rb
+++ /dev/null
@@ -1,297 +0,0 @@
-require 'active_support/json'
-
-module ActionController #:nodoc:
-  # Responsible for exposing a resource to different mime requests,
-  # usually depending on the HTTP verb. The responder is triggered when
-  # <code>respond_with</code> is called. The simplest case to study is a GET request:
-  #
-  #   class PeopleController < ApplicationController
-  #     respond_to :html, :xml, :json
-  #
-  #     def index
-  #       @people = Person.all
-  #       respond_with(@people)
-  #     end
-  #   end
-  #
-  # When a request comes in, for example for an XML response, three steps happen:
-  #
-  #   1) the responder searches for a template at people/index.xml;
-  #
-  #   2) if the template is not available, it will invoke <code>#to_xml</code> on the given resource;
-  #
-  #   3) if the responder does not <code>respond_to :to_xml</code>, call <code>#to_format</code> on it.
-  #
-  # === Built-in HTTP verb semantics
-  #
-  # The default \Rails responder holds semantics for each HTTP verb. Depending on the
-  # content type, verb and the resource status, it will behave differently.
-  #
-  # Using \Rails default responder, a POST request for creating an object could
-  # be written as:
-  #
-  #   def create
-  #     @user = User.new(params[:user])
-  #     flash[:notice] = 'User was successfully created.' if @user.save
-  #     respond_with(@user)
-  #   end
-  #
-  # Which is exactly the same as:
-  #
-  #   def create
-  #     @user = User.new(params[:user])
-  #
-  #     respond_to do |format|
-  #       if @user.save
-  #         flash[:notice] = 'User was successfully created.'
-  #         format.html { redirect_to(@user) }
-  #         format.xml { render xml: @user, status: :created, location: @user }
-  #       else
-  #         format.html { render action: "new" }
-  #         format.xml { render xml: @user.errors, status: :unprocessable_entity }
-  #       end
-  #     end
-  #   end
-  #
-  # The same happens for PATCH/PUT and DELETE requests.
-  #
-  # === Nested resources
-  #
-  # You can supply nested resources as you do in <code>form_for</code> and <code>polymorphic_url</code>.
-  # Consider the project has many tasks example. The create action for
-  # TasksController would be like:
-  #
-  #   def create
-  #     @project = Project.find(params[:project_id])
-  #     @task = @project.tasks.build(params[:task])
-  #     flash[:notice] = 'Task was successfully created.' if @task.save
-  #     respond_with(@project, @task)
-  #   end
-  #
-  # Giving several resources ensures that the responder will redirect to
-  # <code>project_task_url</code> instead of <code>task_url</code>.
-  #
-  # Namespaced and singleton resources require a symbol to be given, as in
-  # polymorphic urls. If a project has one manager which has many tasks, it
-  # should be invoked as:
-  #
-  #   respond_with(@project, :manager, @task)
-  #
-  # Note that if you give an array, it will be treated as a collection,
-  # so the following is not equivalent:
-  #
-  #   respond_with [@project, :manager, @task]
-  #
-  # === Custom options
-  #
-  # <code>respond_with</code> also allows you to pass options that are forwarded
-  # to the underlying render call. Those options are only applied for success
-  # scenarios. For instance, you can do the following in the create method above:
-  #
-  #   def create
-  #     @project = Project.find(params[:project_id])
-  #     @task = @project.tasks.build(params[:task])
-  #     flash[:notice] = 'Task was successfully created.' if @task.save
-  #     respond_with(@project, @task, status: 201)
-  #   end
-  #
-  # This will return status 201 if the task was saved successfully. If not,
-  # it will simply ignore the given options and return status 422 and the
-  # resource errors. You can also override the location to redirect to:
-  #
-  #   respond_with(@project, location: root_path)
-  #
-  # To customize the failure scenario, you can pass a block to
-  # <code>respond_with</code>:
-  #
-  #   def create
-  #     @project = Project.find(params[:project_id])
-  #     @task = @project.tasks.build(params[:task])
-  #     respond_with(@project, @task, status: 201) do |format|
-  #       if @task.save
-  #         flash[:notice] = 'Task was successfully created.'
-  #       else
-  #         format.html { render "some_special_template" }
-  #       end
-  #     end
-  #   end
-  #
-  # Using <code>respond_with</code> with a block follows the same syntax as <code>respond_to</code>.
-  class Responder
-    attr_reader :controller, :request, :format, :resource, :resources, :options
-
-    DEFAULT_ACTIONS_FOR_VERBS = {
-      :post => :new,
-      :patch => :edit,
-      :put => :edit
-    }
-
-    def initialize(controller, resources, options={})
-      @controller = controller
-      @request = @controller.request
-      @format = @controller.formats.first
-      @resource = resources.last
-      @resources = resources
-      @options = options
-      @action = options.delete(:action)
-      @default_response = options.delete(:default_response)
-    end
-
-    delegate :head, :render, :redirect_to,   :to => :controller
-    delegate :get?, :post?, :patch?, :put?, :delete?, :to => :request
-
-    # Undefine :to_json and :to_yaml since it's defined on Object
-    undef_method(:to_json) if method_defined?(:to_json)
-    undef_method(:to_yaml) if method_defined?(:to_yaml)
-
-    # Initializes a new responder and invokes the proper format. If the format is
-    # not defined, call to_format.
-    #
-    def self.call(*args)
-      new(*args).respond
-    end
-
-    # Main entry point for responder responsible to dispatch to the proper format.
-    #
-    def respond
-      method = "to_#{format}"
-      respond_to?(method) ? send(method) : to_format
-    end
-
-    # HTML format does not render the resource, it always attempt to render a
-    # template.
-    #
-    def to_html
-      default_render
-    rescue ActionView::MissingTemplate => e
-      navigation_behavior(e)
-    end
-
-    # to_js simply tries to render a template. If no template is found, raises the error.
-    def to_js
-      default_render
-    end
-
-    # All other formats follow the procedure below. First we try to render a
-    # template, if the template is not available, we verify if the resource
-    # responds to :to_format and display it.
-    #
-    def to_format
-      if get? || !has_errors? || response_overridden?
-        default_render
-      else
-        display_errors
-      end
-    rescue ActionView::MissingTemplate => e
-      api_behavior(e)
-    end
-
-  protected
-
-    # This is the common behavior for formats associated with browsing, like :html, :iphone and so forth.
-    def navigation_behavior(error)
-      if get?
-        raise error
-      elsif has_errors? && default_action
-        render :action => default_action
-      else
-        redirect_to navigation_location
-      end
-    end
-
-    # This is the common behavior for formats associated with APIs, such as :xml and :json.
-    def api_behavior(error)
-      raise error unless resourceful?
-      raise MissingRenderer.new(format) unless has_renderer?
-
-      if get?
-        display resource
-      elsif post?
-        display resource, :status => :created, :location => api_location
-      else
-        head :no_content
-      end
-    end
-
-    # Checks whether the resource responds to the current format or not.
-    #
-    def resourceful?
-      resource.respond_to?("to_#{format}")
-    end
-
-    # Returns the resource location by retrieving it from the options or
-    # returning the resources array.
-    #
-    def resource_location
-      options[:location] || resources
-    end
-    alias :navigation_location :resource_location
-    alias :api_location :resource_location
-
-    # If a response block was given, use it, otherwise call render on
-    # controller.
-    #
-    def default_render
-      if @default_response
-        @default_response.call(options)
-      else
-        controller.default_render(options)
-      end
-    end
-
-    # Display is just a shortcut to render a resource with the current format.
-    #
-    #   display @user, status: :ok
-    #
-    # For XML requests it's equivalent to:
-    #
-    #   render xml: @user, status: :ok
-    #
-    # Options sent by the user are also used:
-    #
-    #   respond_with(@user, status: :created)
-    #   display(@user, status: :ok)
-    #
-    # Results in:
-    #
-    #   render xml: @user, status: :created
-    #
-    def display(resource, given_options={})
-      controller.render given_options.merge!(options).merge!(format => resource)
-    end
-
-    def display_errors
-      controller.render format => resource_errors, :status => :unprocessable_entity
-    end
-
-    # Check whether the resource has errors.
-    #
-    def has_errors?
-      resource.respond_to?(:errors) && !resource.errors.empty?
-    end
-
-    # Check whether the necessary Renderer is available
-    def has_renderer?
-      Renderers::RENDERERS.include?(format)
-    end
-
-    # By default, render the <code>:edit</code> action for HTML requests with errors, unless
-    # the verb was POST.
-    #
-    def default_action
-      @action ||= DEFAULT_ACTIONS_FOR_VERBS[request.request_method_symbol]
-    end
-
-    def resource_errors
-      respond_to?("#{format}_resource_errors", true) ? send("#{format}_resource_errors") : resource.errors
-    end
-
-    def json_resource_errors
-      {:errors => resource.errors}
-    end
-
-    def response_overridden?
-      @default_response.present?
-    end
-  end
-end