`current_application_settings` belongs on `Gitlab::CurrentSettings`

The initializers including this were doing so at the top level, so every object
loaded after them had a `current_application_settings` method. However, if
someone had rack-attack enabled (which was loaded before these initializers), it
would try to load the API, and fail, because `Gitlab::CurrentSettings` didn't
have that method.

To fix this:

1. Don't include `Gitlab::CurrentSettings` at the top level. We do not need
   `Object.new.current_application_settings` to work.
2. Make `Gitlab::CurrentSettings` explicitly `extend self`, as we already use it
   like that in several places.
3. Change the initializers to use that new form.

17 files changed, 31 insertions, 7 deletions

diff --git a/app/controllers/concerns/requires_whitelisted_monitoring_client.rb b/app/controllers/concerns/requires_whitelisted_monitoring_client.rb
index ad2f4bbc486..0218ac83441 100644
--- a/app/controllers/concerns/requires_whitelisted_monitoring_client.rb
+++ b/app/controllers/concerns/requires_whitelisted_monitoring_client.rb
@@ -1,5 +1,8 @@
 module RequiresWhitelistedMonitoringClient
   extend ActiveSupport::Concern
+
+  include Gitlab::CurrentSettings
+
   included do
     before_action :validate_ip_whitelisted_or_valid_token!
   end
diff --git a/app/helpers/application_helper.rb b/app/helpers/application_helper.rb
index 07775a8b159..36bb7015fa1 100644
--- a/app/helpers/application_helper.rb
+++ b/app/helpers/application_helper.rb
@@ -202,7 +202,7 @@ module ApplicationHelper
   end
 
   def support_url
-    current_application_settings.help_page_support_url.presence || promo_url + '/getting-help/'
+    Gitlab::CurrentSettings.current_application_settings.help_page_support_url.presence || promo_url + '/getting-help/'
   end
 
   def page_filter_path(options = {})
diff --git a/app/helpers/application_settings_helper.rb b/app/helpers/application_settings_helper.rb
index 3b76da238e0..04955ed625e 100644
--- a/app/helpers/application_settings_helper.rb
+++ b/app/helpers/application_settings_helper.rb
@@ -1,5 +1,8 @@
 module ApplicationSettingsHelper
   extend self
+
+  include Gitlab::CurrentSettings
+
   delegate  :gravatar_enabled?,
             :signup_enabled?,
             :password_authentication_enabled?,
diff --git a/app/helpers/auth_helper.rb b/app/helpers/auth_helper.rb
index 9c71d6c7f4c..66dc0b1e6f7 100644
--- a/app/helpers/auth_helper.rb
+++ b/app/helpers/auth_helper.rb
@@ -1,4 +1,6 @@
 module AuthHelper
+  include Gitlab::CurrentSettings
+
   PROVIDERS_WITH_ICONS = %w(twitter github gitlab bitbucket google_oauth2 facebook azure_oauth2 authentiq).freeze
   FORM_BASED_PROVIDERS = [/\Aldap/, 'crowd'].freeze
 
diff --git a/app/helpers/projects_helper.rb b/app/helpers/projects_helper.rb
index bee4950e414..c5490a2d1a8 100644
--- a/app/helpers/projects_helper.rb
+++ b/app/helpers/projects_helper.rb
@@ -1,4 +1,6 @@
 module ProjectsHelper
+  include Gitlab::CurrentSettings
+
   def link_to_project(project)
     link_to [project.namespace.becomes(Namespace), project], title: h(project.name) do
       title = content_tag(:span, project.name, class: 'project-name')
diff --git a/app/mailers/base_mailer.rb b/app/mailers/base_mailer.rb
index 654468bc7fe..8e99db444d6 100644
--- a/app/mailers/base_mailer.rb
+++ b/app/mailers/base_mailer.rb
@@ -1,11 +1,13 @@
 class BaseMailer < ActionMailer::Base
+  include Gitlab::CurrentSettings
+
   around_action :render_with_default_locale
 
   helper ApplicationHelper
   helper MarkupHelper
 
   attr_accessor :current_user
-  helper_method :current_user, :can?
+  helper_method :current_user, :can?, :current_application_settings
 
   default from:     proc { default_sender_address.format }
   default reply_to: proc { default_reply_to_address.format }
diff --git a/app/models/concerns/spammable.rb b/app/models/concerns/spammable.rb
index f2707022a4b..731d9b9a745 100644
--- a/app/models/concerns/spammable.rb
+++ b/app/models/concerns/spammable.rb
@@ -28,7 +28,7 @@ module Spammable
 
   def submittable_as_spam?
     if user_agent_detail
-      user_agent_detail.submittable? && current_application_settings.akismet_enabled
+      user_agent_detail.submittable? && Gitlab::CurrentSettings.current_application_settings.akismet_enabled
     else
       false
     end
diff --git a/app/models/project.rb b/app/models/project.rb
index 9d7bea4eb66..d4f665ea725 100644
--- a/app/models/project.rb
+++ b/app/models/project.rb
@@ -19,6 +19,7 @@ class Project < ActiveRecord::Base
   include Routable
 
   extend Gitlab::ConfigHelper
+  extend Gitlab::CurrentSettings
 
   BoardLimitExceeded = Class.new(StandardError)
 
diff --git a/app/models/protected_branch.rb b/app/models/protected_branch.rb
index 5f0d0802ac9..89bfc5f9a9c 100644
--- a/app/models/protected_branch.rb
+++ b/app/models/protected_branch.rb
@@ -2,6 +2,8 @@ class ProtectedBranch < ActiveRecord::Base
   include Gitlab::ShellAdapter
   include ProtectedRef
 
+  extend Gitlab::CurrentSettings
+
   protected_ref_access_levels :merge, :push
 
   # Check if branch name is marked as protected in the system
diff --git a/app/models/snippet.rb b/app/models/snippet.rb
index 09d5ff46618..9533aa7f555 100644
--- a/app/models/snippet.rb
+++ b/app/models/snippet.rb
@@ -10,6 +10,8 @@ class Snippet < ActiveRecord::Base
   include Spammable
   include Editable
 
+  extend Gitlab::CurrentSettings
+
   cache_markdown_field :title, pipeline: :single_line
   cache_markdown_field :description
   cache_markdown_field :content
diff --git a/app/models/user.rb b/app/models/user.rb
index 70787de4b40..78e7c750c3b 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -2,6 +2,7 @@ require 'carrierwave/orm/activerecord'
 
 class User < ActiveRecord::Base
   extend Gitlab::ConfigHelper
+  extend Gitlab::CurrentSettings
 
   include Gitlab::ConfigHelper
   include Gitlab::CurrentSettings
diff --git a/app/policies/base_policy.rb b/app/policies/base_policy.rb
index a605a3457c8..8fa7b2753c7 100644
--- a/app/policies/base_policy.rb
+++ b/app/policies/base_policy.rb
@@ -1,8 +1,6 @@
 require_dependency 'declarative_policy'
 
 class BasePolicy < DeclarativePolicy::Base
-  include Gitlab::CurrentSettings
-
   desc "User is an instance admin"
   with_options scope: :user, score: 0
   condition(:admin) { @user&.admin? }
@@ -15,6 +13,6 @@ class BasePolicy < DeclarativePolicy::Base
 
   desc "The application is restricted from public visibility"
   condition(:restricted_public_level, scope: :global) do
-    current_application_settings.restricted_visibility_levels.include?(Gitlab::VisibilityLevel::PUBLIC)
+    Gitlab::CurrentSettings.current_application_settings.restricted_visibility_levels.include?(Gitlab::VisibilityLevel::PUBLIC)
   end
 end
diff --git a/app/services/akismet_service.rb b/app/services/akismet_service.rb
index 7b5482b3cd1..aa6f0e841c9 100644
--- a/app/services/akismet_service.rb
+++ b/app/services/akismet_service.rb
@@ -1,4 +1,6 @@
 class AkismetService
+  include Gitlab::CurrentSettings
+
   attr_accessor :owner, :text, :options
 
   def initialize(owner, text, options = {})
diff --git a/app/services/auth/container_registry_authentication_service.rb b/app/services/auth/container_registry_authentication_service.rb
index 7dae5880931..9a636346899 100644
--- a/app/services/auth/container_registry_authentication_service.rb
+++ b/app/services/auth/container_registry_authentication_service.rb
@@ -1,6 +1,6 @@
 module Auth
   class ContainerRegistryAuthenticationService < BaseService
-    include Gitlab::CurrentSettings
+    extend Gitlab::CurrentSettings
 
     AUDIENCE = 'container_registry'.freeze
 
diff --git a/app/services/projects/update_pages_service.rb b/app/services/projects/update_pages_service.rb
index 394b336a638..f6b83a2f621 100644
--- a/app/services/projects/update_pages_service.rb
+++ b/app/services/projects/update_pages_service.rb
@@ -1,5 +1,7 @@
 module Projects
   class UpdatePagesService < BaseService
+    include Gitlab::CurrentSettings
+
     BLOCK_SIZE = 32.kilobytes
     MAX_SIZE = 1.terabyte
     SITE_PATH = 'public/'.freeze
diff --git a/app/services/upload_service.rb b/app/services/upload_service.rb
index 6c5b2baff41..76700dfcdee 100644
--- a/app/services/upload_service.rb
+++ b/app/services/upload_service.rb
@@ -1,4 +1,6 @@
 class UploadService
+  include Gitlab::CurrentSettings
+
   def initialize(model, file, uploader_class = FileUploader)
     @model, @file, @uploader_class = model, file, uploader_class
   end
diff --git a/app/services/users/build_service.rb b/app/services/users/build_service.rb
index ff234a3440f..6f05500adea 100644
--- a/app/services/users/build_service.rb
+++ b/app/services/users/build_service.rb
@@ -1,5 +1,7 @@
 module Users
   class BuildService < BaseService
+    include Gitlab::CurrentSettings
+
     def initialize(current_user, params = {})
       @current_user = current_user
       @params = params.dup