Merge pull request #22506 from derekprior/dp-redirect_to_back_or_default

Add `redirect_to_back_or_default`

Merge pull request #22506 from derekprior/dp-redirect_to_back_or_default
Add `redirect_to_back_or_default`
79ac05f5 · Sean Griffin · f0f4f543 · dc4429ca · 79ac05f5 · 79ac05f5
5 changed file
--- a/actionpack/CHANGELOG.md
+++ b/actionpack/CHANGELOG.md
+*   Deprecate `redirect_to :back` in favor of `redirect_back`, which accepts a
+    required `fallback_location` argument, thus eliminating the possibility of a
+    `RedirectBackError`.
+
+    *Derek Prior*
+
+*   Add `redirect_back` method to `ActionController::Redirecting` to provide a
+    way to safely redirect to the `HTTP_REFERER` if it is present, falling back
+    to a provided redirect otherwise.
+
+    *Derek Prior*
+
 *   `ActionController::TestCase` will be moved to it's own gem in Rails 5.1

    With the speed improvements made to `ActionDispatch::IntegrationTest` we no

--- a/actionpack/lib/action_controller/metal/redirecting.rb
+++ b/actionpack/lib/action_controller/metal/redirecting.rb
@@ -20,8 +20,6 @@ module Redirecting
    # * <tt>String</tt> starting with <tt>protocol://</tt> (like <tt>http://</tt>) or a protocol relative reference (like <tt>//</tt>) - Is passed straight through as the target for redirection.
    # * <tt>String</tt> not containing a protocol - The current protocol and host is prepended to the string.
    # * <tt>Proc</tt> - A block that will be executed in the controller's context. Should return any option accepted by +redirect_to+.
-    # * <tt>:back</tt> - Back to the page that issued the request. Useful for forms that are triggered from multiple places.
-    #   Short-hand for <tt>redirect_to(request.env["HTTP_REFERER"])</tt>
    #
    # === Examples:
    #
@@ -30,7 +28,6 @@ module Redirecting
    #   redirect_to "http://www.rubyonrails.org"
    #   redirect_to "/images/screenshot.jpg"
    #   redirect_to articles_url
-    #   redirect_to :back
    #   redirect_to proc { edit_post_url(@post) }
    #
    # The redirection happens as a "302 Found" header unless otherwise specified using the <tt>:status</tt> option:
@@ -61,10 +58,6 @@ module Redirecting
    #   redirect_to post_url(@post), status: 301, flash: { updated_post_id: @post.id }
    #   redirect_to({ action: 'atom' }, alert: "Something serious happened")
    #
-    # When using <tt>redirect_to :back</tt>, if there is no referrer,
-    # <tt>ActionController::RedirectBackError</tt> will be raised. You
-    # may specify some fallback behavior for this case by rescuing
-    # <tt>ActionController::RedirectBackError</tt>.
    def redirect_to(options = {}, response_status = {}) #:doc:
      raise ActionControllerError.new("Cannot redirect to nil!") unless options
      raise ActionControllerError.new("Cannot redirect to a parameter hash!") if options.is_a?(ActionController::Parameters)
@@ -75,6 +68,26 @@ def redirect_to(options = {}, response_status = {}) #:doc:
      self.response_body = "<html><body>You are being <a href=\"#{ERB::Util.unwrapped_html_escape(location)}\">redirected</a>.</body></html>"
    end

+    # Redirects the browser to the page that issued the request if possible,
+    # otherwise redirects to provided default fallback location.
+    #
+    #   redirect_back fallback_location: { action: "show", id: 5 }
+    #   redirect_back fallback_location: post
+    #   redirect_back fallback_location: "http://www.rubyonrails.org"
+    #   redirect_back fallback_location:  "/images/screenshot.jpg"
+    #   redirect_back fallback_location:  articles_url
+    #   redirect_back fallback_location:  proc { edit_post_url(@post) }
+    #
+    # All options that can be passed to <tt>redirect_to</tt> are accepted as
+    # options and the behavior is indetical.
+    def redirect_back(fallback_location:, **args)
+      if referer = request.headers["Referer"]
+        redirect_to referer, **args
+      else
+        redirect_to fallback_location, **args
+      end
+    end
+
    def _compute_redirect_to_location(request, options) #:nodoc:
      case options
      # The scheme name consist of a letter followed by any combination of
@@ -87,6 +100,12 @@ def _compute_redirect_to_location(request, options) #:nodoc:
      when String
        request.protocol + request.host_with_port + options
      when :back
+        ActiveSupport::Deprecation.warn(<<-MESSAGE.squish)
+          `redirect_to :back` is deprecated and will be removed from Rails 5.1.
+          Please use `redirect_back(fallback_location: fallback_location)` where
+          `fallback_location` represents the location to use if the request has
+          no HTTP referer information.
+        MESSAGE
        request.headers["Referer"] or raise RedirectBackError
      when Proc
        _compute_redirect_to_location request, options.call

--- a/actionpack/test/controller/redirect_test.rb
+++ b/actionpack/test/controller/redirect_test.rb
@@ -42,6 +42,10 @@ def redirect_to_back_with_status
    redirect_to :back, :status => 307
  end

+  def redirect_back_with_status
+    redirect_back(fallback_location: "/things/stuff", status: 307)
+  end
+
  def host_redirect
    redirect_to :action => "other_host", :only_path => false, :host => 'other.test.host'
  end
@@ -187,7 +191,11 @@ def test_relative_url_redirect_with_status_hash

  def test_redirect_to_back_with_status
    @request.env["HTTP_REFERER"] = "http://www.example.com/coming/from"
-    get :redirect_to_back_with_status
+
+    assert_deprecated do
+      get :redirect_to_back_with_status
+    end
+
    assert_response 307
    assert_equal "http://www.example.com/coming/from", redirect_to_url
  end
@@ -236,7 +244,11 @@ def test_redirect_to_url_with_network_path_reference

  def test_redirect_to_back
    @request.env["HTTP_REFERER"] = "http://www.example.com/coming/from"
-    get :redirect_to_back
+
+    assert_deprecated do
+      get :redirect_to_back
+    end
+
    assert_response :redirect
    assert_equal "http://www.example.com/coming/from", redirect_to_url
  end
@@ -244,10 +256,32 @@ def test_redirect_to_back
  def test_redirect_to_back_with_no_referer
    assert_raise(ActionController::RedirectBackError) {
      @request.env["HTTP_REFERER"] = nil
+
+      assert_deprecated do
+        get :redirect_to_back
+      end
+
      get :redirect_to_back
    }
  end

+  def test_redirect_back
+    referer = "http://www.example.com/coming/from"
+    @request.env["HTTP_REFERER"] = referer
+
+    get :redirect_back_with_status
+
+    assert_response 307
+    assert_equal referer, redirect_to_url
+  end
+
+  def test_redirect_back_with_no_referer
+    get :redirect_back_with_status
+
+    assert_response 307
+    assert_equal "http://test.host/things/stuff", redirect_to_url
+  end
+
  def test_redirect_to_record
    with_routing do |set|
      set.draw do

--- a/guides/source/action_controller_overview.md
+++ b/guides/source/action_controller_overview.md
@@ -1150,7 +1150,7 @@ class ApplicationController < ActionController::Base

    def user_not_authorized
      flash[:error] = "You don't have access to this section."
-      redirect_to :back
+      redirect_back(fallback_location: root_path)
    end
 end


--- a/guides/source/layouts_and_rendering.md
+++ b/guides/source/layouts_and_rendering.md
@@ -622,10 +622,13 @@ Another way to handle returning responses to an HTTP request is with `redirect_t
 redirect_to photos_url
 ```

-You can use `redirect_to` with any arguments that you could use with `link_to` or `url_for`. There's also a special redirect that sends the user back to the page they just came from:
+You can use `redirect_back` to return the user to the page they just came from.
+This location is pulled from the `HTTP_REFERER` header which is not guaranteed
+to be set by the browser, so you must provide the `fallback_location`
+to use in this case.

 ```ruby
-redirect_to :back
+redirect_back(fallback_location: root_path)
 ```

 #### Getting a Different Redirect Status Code