Refactor requires login logic, reduce duplicate code

This also corrects the positioning in the chain of the check
and removes misuse of prepend_before_action

app/controllers/about_controller.rb

@@ -1,7 +1,9 @@
 require_dependency 'rate_limiter'
 
 class AboutController < ApplicationController
-  prepend_before_action :check_xhr, :ensure_logged_in, only: [:live_post_counts]
+
+  requires_login only: [:live_post_counts]
+
   skip_before_action :check_xhr, only: [:index]
 
   def index

app/controllers/admin/admin_controller.rb

@@ -1,7 +1,7 @@
 class Admin::AdminController < ApplicationController
 
-  prepend_before_action :check_xhr, :ensure_logged_in
+  requires_login
-  prepend_before_action :check_xhr, :ensure_staff
+  before_action :ensure_staff
 
   def index
     render body: nil

app/controllers/application_controller.rb

@@ -48,8 +48,9 @@ class ApplicationController < ActionController::Base
   before_action :set_mobile_view
   before_action :block_if_readonly_mode
   before_action :authorize_mini_profiler
-  before_action :preload_json
   before_action :redirect_to_login_if_required
+  before_action :block_if_requires_login
+  before_action :preload_json
   before_action :check_xhr
   after_action  :add_readonly_header
   after_action  :perform_refresh_session
@@ -570,6 +571,28 @@ class ApplicationController < ActionController::Base
       raise RenderEmpty.new unless ((request.format && request.format.json?) || request.xhr?)
     end
 
+    def self.requires_login(arg = {})
+      @requires_login_arg = arg
+    end
+
+    def self.requires_login_arg
+      @requires_login_arg
+    end
+
+    def block_if_requires_login
+      if arg = self.class.requires_login_arg
+        check =
+          if except = arg[:except]
+            !except.include?(action_name.to_sym)
+          elsif only = arg[:only]
+            only.include?(action_name.to_sym)
+          else
+            true
+          end
+        ensure_logged_in if check
+      end
+    end
+
     def ensure_logged_in
       raise Discourse::NotLoggedIn.new unless current_user.present?
     end

app/controllers/categories_controller.rb

@@ -2,7 +2,8 @@ require_dependency 'category_serializer'
 
 class CategoriesController < ApplicationController
 
-  prepend_before_action :check_xhr, :ensure_logged_in, except: [:index, :categories_and_latest, :show, :redirect, :find_by_slug]
+  requires_login except: [:index, :categories_and_latest, :show, :redirect, :find_by_slug]
+
   before_action :fetch_category, only: [:show, :update, :destroy]
   before_action :initialize_staff_action_logger, only: [:create, :update, :destroy]
   skip_before_action :check_xhr, only: [:index, :categories_and_latest, :redirect]

app/controllers/category_hashtags_controller.rb

@@ -1,5 +1,5 @@
 class CategoryHashtagsController < ApplicationController
-  prepend_before_action :check_xhr, :ensure_logged_in
+  requires_login
 
   def check
     category_slugs = params[:category_slugs]

app/controllers/composer_controller.rb

@@ -2,7 +2,7 @@ require_dependency 'html_to_markdown'
 
 class ComposerController < ApplicationController
 
-  prepend_before_action :check_xhr, :ensure_logged_in
+  requires_login
 
   def parse_html
     markdown_text = HtmlToMarkdown.new(params[:html]).to_markdown

app/controllers/composer_messages_controller.rb

@@ -2,7 +2,7 @@ require_dependency 'composer_messages_finder'
 
 class ComposerMessagesController < ApplicationController
 
-  prepend_before_action :check_xhr, :ensure_logged_in
+  requires_login
 
   def index
     finder = ComposerMessagesFinder.new(current_user, params.slice(:composer_action, :topic_id, :post_id))

app/controllers/draft_controller.rb

@@ -1,5 +1,6 @@
 class DraftController < ApplicationController
-  prepend_before_action :ensure_logged_in
+  requires_login
+
   skip_before_action :check_xhr, :preload_json
 
   def show

app/controllers/groups_controller.rb

@@ -1,6 +1,6 @@
 class GroupsController < ApplicationController
 
-  prepend_before_action :check_xhr, :ensure_logged_in, only: [
+  requires_login only: [
     :set_notifications,
     :mentionable,
     :messageable,

app/controllers/inline_onebox_controller.rb

@@ -1,7 +1,7 @@
 require_dependency 'inline_oneboxer'
 
 class InlineOneboxController < ApplicationController
-  prepend_before_action :check_xhr, :ensure_logged_in
+  requires_login
 
   def show
     oneboxes = InlineOneboxer.new(params[:urls] || []).process

app/controllers/invites_controller.rb

@@ -2,7 +2,7 @@ require_dependency 'rate_limiter'
 
 class InvitesController < ApplicationController
 
-  prepend_before_action :check_xhr, :ensure_logged_in, only: [
+  requires_login only: [
     :destroy, :create, :create_invite_link, :rescind_all_invites,
     :resend_invite, :resend_all_invites, :upload_csv
   ]

app/controllers/notifications_controller.rb

@@ -2,7 +2,7 @@ require_dependency 'notification_serializer'
 
 class NotificationsController < ApplicationController
 
-  prepend_before_action :check_xhr, :ensure_logged_in
+  requires_login
 
   def index
     user =

app/controllers/onebox_controller.rb

@@ -1,7 +1,7 @@
 require_dependency 'oneboxer'
 
 class OneboxController < ApplicationController
-  prepend_before_action :check_xhr, :ensure_logged_in
+  requires_login
 
   def show
     unless params[:refresh] == 'true'

app/controllers/post_actions_controller.rb

@@ -1,7 +1,8 @@
 require_dependency 'discourse'
 
 class PostActionsController < ApplicationController
-  prepend_before_action :check_xhr, :ensure_logged_in
+  requires_login
+
   before_action :fetch_post_from_params
   before_action :fetch_post_action_type_id_from_params
 

app/controllers/posts_controller.rb

@@ -8,7 +8,7 @@ require_dependency 'post_locker'
 
 class PostsController < ApplicationController
 
-  prepend_before_action :check_xhr, :ensure_logged_in, except: [
+  requires_login except: [
     :show,
     :replies,
     :by_number,

app/controllers/steps_controller.rb

@@ -3,9 +3,9 @@ require_dependency 'wizard/builder'
 require_dependency 'wizard/step_updater'
 
 class StepsController < ApplicationController
+  requires_login
 
   before_action :ensure_wizard_enabled
-  prepend_before_action :check_xhr, :ensure_logged_in
   before_action :ensure_admin
 
   def update

app/controllers/tag_groups_controller.rb

@@ -1,5 +1,6 @@
 class TagGroupsController < ApplicationController
-  prepend_before_action :check_xhr, :ensure_logged_in, except: [:index, :show]
+  requires_login except: [:index, :show]
+
   skip_before_action :check_xhr, only: [:index, :show]
   before_action :fetch_tag_group, only: [:show, :update, :destroy]
 

app/controllers/tags_controller.rb

@@ -7,7 +7,7 @@ class TagsController < ::ApplicationController
 
   before_action :ensure_tags_enabled
 
-  prepend_before_action :check_xhr, :ensure_logged_in, except: [
+  requires_login except: [
     :index,
     :show,
     :tag_feed,

app/controllers/topics_controller.rb

@@ -6,7 +6,7 @@ require_dependency 'discourse_event'
 require_dependency 'rate_limiter'
 
 class TopicsController < ApplicationController
-  prepend_before_action :check_xhr, :ensure_logged_in, only: [
+  requires_login only: [
     :timings,
     :destroy_timings,
     :update,

app/controllers/uploads_controller.rb

@@ -2,7 +2,8 @@ require "mini_mime"
 require_dependency 'upload_creator'
 
 class UploadsController < ApplicationController
-  prepend_before_action :check_xhr, :ensure_logged_in, except: [:show]
+  requires_login except: [:show]
+
   skip_before_action :preload_json, :check_xhr, :redirect_to_login_if_required, only: [:show]
 
   def create

app/controllers/user_api_keys_controller.rb

@@ -2,7 +2,7 @@ class UserApiKeysController < ApplicationController
 
   layout 'no_ember'
 
-  prepend_before_action :check_xhr, :ensure_logged_in, only: [:create, :revoke, :undo_revoke]
+  requires_login only: [:create, :revoke, :undo_revoke]
   skip_before_action :redirect_to_login_if_required, only: [:new]
   skip_before_action :check_xhr, :preload_json
 

app/controllers/users_controller.rb

@@ -9,7 +9,7 @@ class UsersController < ApplicationController
 
   skip_before_action :authorize_mini_profiler, only: [:avatar]
 
-  prepend_before_action :check_xhr, :ensure_logged_in, only: [
+  requires_login only: [
     :username, :update, :user_preferences_redirect, :upload_user_image,
     :pick_avatar, :destroy_user_image, :destroy, :check_emails, :topic_tracking_state,
     :preferences

app/controllers/users_email_controller.rb

@@ -4,7 +4,7 @@ require_dependency 'email_updater'
 
 class UsersEmailController < ApplicationController
 
-  prepend_before_action :check_xhr, :ensure_logged_in, only: [:index, :update]
+  requires_login only: [:index, :update]
 
   skip_before_action :check_xhr, only: [:confirm]
   skip_before_action :redirect_to_login_if_required, only: [:confirm]

app/controllers/wizard_controller.rb

@@ -2,8 +2,9 @@ require_dependency 'wizard'
 require_dependency 'wizard/builder'
 
 class WizardController < ApplicationController
-  prepend_before_action :check_xhr, :ensure_admin, except: [:qunit]
+  requires_login except: [:qunit]
-  prepend_before_action :check_xhr, :ensure_logged_in, except: [:qunit]
+
+  before_action :ensure_admin, except: [:qunit]
   before_action :ensure_wizard_enabled, only: [:index]
   skip_before_action :check_xhr, :preload_json