Merge branch 'fix-n-plus-one-when-getting-notification-settings-for-recipients' into 'master'

Use Goldiloader for handling N+1 queries

See merge request gitlab-org/gitlab-ce!18217

Gemfile

@@ -441,3 +441,5 @@ gem 'grape_logging', '~> 1.7'
 # Asset synchronization
 gem 'asset_sync', '~> 2.2.0'
+
+gem 'goldiloader', '~> 2.0'

Gemfile.lock

@@ -320,6 +320,9 @@ GEM
       rubyntlm (~> 0.5)
     globalid (0.4.1)
       activesupport (>= 4.2.0)
+    goldiloader (2.0.1)
+      activerecord (>= 4.2, < 5.2)
+      activesupport (>= 4.2, < 5.2)
     gollum-grit_adapter (1.0.1)
       gitlab-grit (~> 2.7, >= 2.7.1)
     gollum-lib (4.2.7)
@@ -1067,6 +1070,7 @@ DEPENDENCIES
   gitlab-markup (~> 1.6.2)
   gitlab-styles (~> 2.3)
   gitlab_omniauth-ldap (~> 2.0.4)
+  goldiloader (~> 2.0)
   gollum-lib (~> 4.2)
   gollum-rugged_adapter (~> 0.4.4)
   gon (~> 6.1.0)

app/models/ci/runner.rb

@@ -13,7 +13,7 @@ module Ci
     has_many :builds
     has_many :runner_projects, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
-    has_many :projects, through: :runner_projects
+    has_many :projects, -> { auto_include(false) }, through: :runner_projects
     has_one :last_build, ->() { order('id DESC') }, class_name: 'Ci::Build'

app/models/clusters/cluster.rb

@@ -15,7 +15,7 @@ module Clusters
     belongs_to :user
     has_many :cluster_projects, class_name: 'Clusters::Project'
-    has_many :projects, through: :cluster_projects, class_name: '::Project'
+    has_many :projects, -> { auto_include(false) }, through: :cluster_projects, class_name: '::Project'
     # we force autosave to happen when we save `Cluster` model
     has_one :provider_gcp, class_name: 'Clusters::Providers::Gcp', autosave: true

app/models/concerns/issuable.rb

@@ -48,7 +48,7 @@ module Issuable
     end
     has_many :label_links, as: :target, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
-    has_many :labels, through: :label_links
+    has_many :labels, -> { auto_include(false) }, through: :label_links
     has_many :todos, as: :target, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
     has_one :metrics

app/models/concerns/resolvable_discussion.rb

@@ -102,7 +102,7 @@ module ResolvableDiscussion
     yield(notes_relation)
     # Set the notes array to the updated notes
-    @notes = notes_relation.fresh.to_a # rubocop:disable Gitlab/ModuleWithInstanceVariables
+    @notes = notes_relation.fresh.auto_include(false).to_a # rubocop:disable Gitlab/ModuleWithInstanceVariables
     self.class.memoized_values.each do |name|
       clear_memoization(name)

app/models/deploy_key.rb

@@ -2,7 +2,7 @@ class DeployKey < Key
   include IgnorableColumn
   has_many :deploy_keys_projects, inverse_of: :deploy_key, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
-  has_many :projects, through: :deploy_keys_projects
+  has_many :projects, -> { auto_include(false) }, through: :deploy_keys_projects
   scope :in_projects, ->(projects) { joins(:deploy_keys_projects).where('deploy_keys_projects.project_id in (?)', projects) }
   scope :are_public,  -> { where(public: true) }

app/models/deploy_token.rb

@@ -8,7 +8,7 @@ class DeployToken < ActiveRecord::Base
   default_value_for(:expires_at) { Forever.date }
   has_many :project_deploy_tokens, inverse_of: :deploy_token
-  has_many :projects, through: :project_deploy_tokens
+  has_many :projects, -> { auto_include(false) }, through: :project_deploy_tokens
   validate :ensure_at_least_one_scope
   before_save :ensure_token

app/models/fork_network.rb

 class ForkNetwork < ActiveRecord::Base
   belongs_to :root_project, class_name: 'Project'
   has_many :fork_network_members
-  has_many :projects, through: :fork_network_members
+  has_many :projects, -> { auto_include(false) }, through: :fork_network_members
   after_create :add_root_as_member, if: :root_project

app/models/group.rb

@@ -12,9 +12,9 @@ class Group < Namespace
   has_many :group_members, -> { where(requested_at: nil) }, dependent: :destroy, as: :source # rubocop:disable Cop/ActiveRecordDependent
   alias_method :members, :group_members
-  has_many :users, through: :group_members
+  has_many :users, -> { auto_include(false) }, through: :group_members
   has_many :owners,
-    -> { where(members: { access_level: Gitlab::Access::OWNER }) },
+    -> { where(members: { access_level: Gitlab::Access::OWNER }).auto_include(false) },
     through: :group_members,
     source: :user
@@ -23,7 +23,7 @@ class Group < Namespace
   has_many :milestones
   has_many :project_group_links, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
-  has_many :shared_projects, through: :project_group_links, source: :project
+  has_many :shared_projects, -> { auto_include(false) }, through: :project_group_links, source: :project
   has_many :notification_settings, dependent: :destroy, as: :source # rubocop:disable Cop/ActiveRecordDependent
   has_many :labels, class_name: 'GroupLabel'
   has_many :variables, class_name: 'Ci::GroupVariable'

app/models/issue.rb

@@ -34,7 +34,7 @@ class Issue < ActiveRecord::Base
     dependent: :delete_all # rubocop:disable Cop/ActiveRecordDependent
   has_many :issue_assignees
-  has_many :assignees, class_name: "User", through: :issue_assignees
+  has_many :assignees, -> { auto_include(false) }, class_name: "User", through: :issue_assignees
   validates :project, presence: true

app/models/label.rb

@@ -18,8 +18,8 @@ class Label < ActiveRecord::Base
   has_many :lists, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
   has_many :priorities, class_name: 'LabelPriority'
   has_many :label_links, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
-  has_many :issues, through: :label_links, source: :target, source_type: 'Issue'
-  has_many :merge_requests, through: :label_links, source: :target, source_type: 'MergeRequest'
+  has_many :issues, -> { auto_include(false) }, through: :label_links, source: :target, source_type: 'Issue'
+  has_many :merge_requests, -> { auto_include(false) }, through: :label_links, source: :target, source_type: 'MergeRequest'
   before_validation :strip_whitespace_from_title_and_color

app/models/lfs_object.rb

@@ -3,7 +3,7 @@ class LfsObject < ActiveRecord::Base
   include ObjectStorage::BackgroundMove
   has_many :lfs_objects_projects, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
-  has_many :projects, through: :lfs_objects_projects
+  has_many :projects, -> { auto_include(false) }, through: :lfs_objects_projects
   scope :with_files_stored_locally, -> { where(file_store: [nil, LfsObjectUploader::Store::LOCAL]) }

app/models/milestone.rb

@@ -22,7 +22,7 @@ class Milestone < ActiveRecord::Base
   belongs_to :group
   has_many :issues
-  has_many :labels, -> { distinct.reorder('labels.title') },  through: :issues
+  has_many :labels, -> { distinct.reorder('labels.title').auto_include(false) }, through: :issues
   has_many :merge_requests
   has_many :events, as: :target, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent

app/models/project.rb

@@ -138,11 +138,11 @@ class Project < ActiveRecord::Base
   has_one :packagist_service
   # TODO: replace these relations with the fork network versions
-  has_one  :forked_project_link,  foreign_key: "forked_to_project_id"
-  has_one  :forked_from_project,  through:   :forked_project_link
+  has_one  :forked_project_link, foreign_key: "forked_to_project_id"
+  has_one  :forked_from_project, -> { auto_include(false) }, through:   :forked_project_link
   has_many :forked_project_links, foreign_key: "forked_from_project_id"
-  has_many :forks,                through:     :forked_project_links, source: :forked_to_project
+  has_many :forks, -> { auto_include(false) }, through: :forked_project_links, source: :forked_to_project
   # TODO: replace these relations with the fork network versions
   has_one :root_of_fork_network,
@@ -150,7 +150,7 @@ class Project < ActiveRecord::Base
           inverse_of: :root_project,
           class_name: 'ForkNetwork'
   has_one :fork_network_member
-  has_one :fork_network, through: :fork_network_member
+  has_one :fork_network, -> { auto_include(false) }, through: :fork_network_member
   # Merge Requests for target project should be removed with it
   has_many :merge_requests, foreign_key: 'target_project_id'
@@ -167,27 +167,27 @@ class Project < ActiveRecord::Base
   has_many :protected_tags
   has_many :project_authorizations
-  has_many :authorized_users, through: :project_authorizations, source: :user, class_name: 'User'
+  has_many :authorized_users, -> { auto_include(false) }, through: :project_authorizations, source: :user, class_name: 'User'
   has_many :project_members, -> { where(requested_at: nil) },
     as: :source, dependent: :delete_all # rubocop:disable Cop/ActiveRecordDependent
   alias_method :members, :project_members
-  has_many :users, through: :project_members
+  has_many :users, -> { auto_include(false) }, through: :project_members
   has_many :requesters, -> { where.not(requested_at: nil) },
     as: :source, class_name: 'ProjectMember', dependent: :delete_all # rubocop:disable Cop/ActiveRecordDependent
   has_many :members_and_requesters, as: :source, class_name: 'ProjectMember'
   has_many :deploy_keys_projects
-  has_many :deploy_keys, through: :deploy_keys_projects
+  has_many :deploy_keys, -> { auto_include(false) }, through: :deploy_keys_projects
   has_many :users_star_projects
-  has_many :starrers, through: :users_star_projects, source: :user
+  has_many :starrers, -> { auto_include(false) }, through: :users_star_projects, source: :user
   has_many :releases
   has_many :lfs_objects_projects, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
-  has_many :lfs_objects, through: :lfs_objects_projects
+  has_many :lfs_objects, -> { auto_include(false) }, through: :lfs_objects_projects
   has_many :lfs_file_locks
   has_many :project_group_links
-  has_many :invited_groups, through: :project_group_links, source: :group
+  has_many :invited_groups, -> { auto_include(false) }, through: :project_group_links, source: :group
   has_many :pages_domains
   has_many :todos
   has_many :notification_settings, as: :source, dependent: :delete_all # rubocop:disable Cop/ActiveRecordDependent
@@ -199,7 +199,7 @@ class Project < ActiveRecord::Base
   has_one :statistics, class_name: 'ProjectStatistics'
   has_one :cluster_project, class_name: 'Clusters::Project'
-  has_many :clusters, through: :cluster_project, class_name: 'Clusters::Cluster'
+  has_many :clusters, -> { auto_include(false) }, through: :cluster_project, class_name: 'Clusters::Cluster'
   # Container repositories need to remove data from the container registry,
   # which is not managed by the DB. Hence we're still using dependent: :destroy
@@ -216,16 +216,16 @@ class Project < ActiveRecord::Base
   has_many :builds, class_name: 'Ci::Build', inverse_of: :project, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
   has_many :build_trace_section_names, class_name: 'Ci::BuildTraceSectionName'
   has_many :runner_projects, class_name: 'Ci::RunnerProject'
-  has_many :runners, through: :runner_projects, source: :runner, class_name: 'Ci::Runner'
+  has_many :runners, -> { auto_include(false) }, through: :runner_projects, source: :runner, class_name: 'Ci::Runner'
   has_many :variables, class_name: 'Ci::Variable'
   has_many :triggers, class_name: 'Ci::Trigger'
   has_many :environments
   has_many :deployments
   has_many :pipeline_schedules, class_name: 'Ci::PipelineSchedule'
   has_many :project_deploy_tokens
-  has_many :deploy_tokens, through: :project_deploy_tokens
-  has_many :active_runners, -> { active }, through: :runner_projects, source: :runner, class_name: 'Ci::Runner'
+  has_many :deploy_tokens, -> { auto_include(false) }, through: :project_deploy_tokens
+  has_many :active_runners, -> { active.auto_include(false) }, through: :runner_projects, source: :runner, class_name: 'Ci::Runner'
   has_one :auto_devops, class_name: 'ProjectAutoDevops'
   has_many :custom_attributes, class_name: 'ProjectCustomAttribute'

app/models/todo.rb

@@ -22,7 +22,7 @@ class Todo < ActiveRecord::Base
   belongs_to :author, class_name: "User"
   belongs_to :note
   belongs_to :project
-  belongs_to :target, polymorphic: true, touch: true # rubocop:disable Cop/PolymorphicAssociations
+  belongs_to :target, -> { auto_include(false) }, polymorphic: true, touch: true # rubocop:disable Cop/PolymorphicAssociations
   belongs_to :user
   delegate :name, :email, to: :author, prefix: true, allow_nil: true

app/models/user.rb

@@ -96,23 +96,23 @@ class User < ActiveRecord::Base
   # Groups
   has_many :members
   has_many :group_members, -> { where(requested_at: nil) }, source: 'GroupMember'
-  has_many :groups, through: :group_members
-  has_many :owned_groups, -> { where members: { access_level: Gitlab::Access::OWNER } }, through: :group_members, source: :group
-  has_many :masters_groups, -> { where members: { access_level: Gitlab::Access::MASTER } }, through: :group_members, source: :group
+  has_many :groups, -> { auto_include(false) }, through: :group_members
+  has_many :owned_groups, -> { where(members: { access_level: Gitlab::Access::OWNER }).auto_include(false) }, through: :group_members, source: :group
+  has_many :masters_groups, -> { where(members: { access_level: Gitlab::Access::MASTER }).auto_include(false) }, through: :group_members, source: :group
   # Projects
-  has_many :groups_projects,          through: :groups, source: :projects
-  has_many :personal_projects,        through: :namespace, source: :projects
+  has_many :groups_projects, -> { auto_include(false) }, through: :groups, source: :projects
+  has_many :personal_projects, -> { auto_include(false) }, through: :namespace, source: :projects
   has_many :project_members, -> { where(requested_at: nil) }
-  has_many :projects,                 through: :project_members
-  has_many :created_projects,         foreign_key: :creator_id, class_name: 'Project'
+  has_many :projects, -> { auto_include(false) }, through: :project_members
+  has_many :created_projects, foreign_key: :creator_id, class_name: 'Project'
   has_many :users_star_projects, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
-  has_many :starred_projects, through: :users_star_projects, source: :project
+  has_many :starred_projects, -> { auto_include(false) }, through: :users_star_projects, source: :project
   has_many :project_authorizations
-  has_many :authorized_projects, through: :project_authorizations, source: :project
+  has_many :authorized_projects, -> { auto_include(false) }, through: :project_authorizations, source: :project
   has_many :user_interacted_projects
-  has_many :project_interactions, through: :user_interacted_projects, source: :project, class_name: 'Project'
+  has_many :project_interactions, -> { auto_include(false) }, through: :user_interacted_projects, source: :project, class_name: 'Project'
   has_many :snippets,                 dependent: :destroy, foreign_key: :author_id # rubocop:disable Cop/ActiveRecordDependent
   has_many :notes,                    dependent: :destroy, foreign_key: :author_id # rubocop:disable Cop/ActiveRecordDependent
@@ -132,7 +132,7 @@ class User < ActiveRecord::Base
   has_many :triggers,                 dependent: :destroy, class_name: 'Ci::Trigger', foreign_key: :owner_id # rubocop:disable Cop/ActiveRecordDependent
   has_many :issue_assignees
-  has_many :assigned_issues, class_name: "Issue", through: :issue_assignees, source: :issue
+  has_many :assigned_issues, -> { auto_include(false) }, class_name: "Issue", through: :issue_assignees, source: :issue
   has_many :assigned_merge_requests,  dependent: :nullify, foreign_key: :assignee_id, class_name: "MergeRequest" # rubocop:disable Cop/ActiveRecordDependent
   has_many :custom_attributes, class_name: 'UserCustomAttribute'

changelogs/unreleased/fix-n-plus-one-when-getting-notification-settings-for-recipients.yml

+---
+title: Add Goldiloader to fix N+1 issues when calculating email recipients
+merge_request:
+author:
+type: performance

rubocop/cop/gitlab/has_many_through_scope.rb

+require 'gitlab/styles/rubocop/model_helpers'
+
+module RuboCop
+  module Cop
+    module Gitlab
+      class HasManyThroughScope < RuboCop::Cop::Cop
+        include ::Gitlab::Styles::Rubocop::ModelHelpers
+
+        MSG = 'Always provide an explicit scope calling auto_include(false) when using has_many :through'.freeze
+
+        def_node_search :through?, <<~PATTERN
+          (pair (sym :through) _)
+        PATTERN
+
+        def_node_matcher :has_many_through?, <<~PATTERN
+          (send nil? :has_many ... #through?)
+        PATTERN
+
+        def_node_search :disables_auto_include?, <<~PATTERN
+          (send _ :auto_include false)
+        PATTERN
+
+        def_node_matcher :scope_disables_auto_include?, <<~PATTERN
+          (block (send nil? :lambda) _ #disables_auto_include?)
+        PATTERN
+
+        def on_send(node)
+          return unless in_model?(node)
+          return unless has_many_through?(node)
+
+          target = node
+          scope_argument = node.children[3]
+
+          if scope_argument.children[0].children.last == :lambda
+            return if scope_disables_auto_include?(scope_argument)
+
+            target = scope_argument
+          end
+
+          add_offense(target, location: :expression)
+        end
+      end
+    end
+  end
+end

rubocop/rubocop.rb

 # rubocop:disable Naming/FileName
+require_relative 'cop/gitlab/has_many_through_scope'
+require_relative 'cop/gitlab/httparty'
 require_relative 'cop/gitlab/module_with_instance_variables'
 require_relative 'cop/gitlab/predicate_memoization'
-require_relative 'cop/gitlab/httparty'
 require_relative 'cop/include_sidekiq_worker'
 require_relative 'cop/line_break_around_conditional_block'
 require_relative 'cop/migration/add_column'