Merge branch 'foreign-keys-for-project-model' into 'master'

Add foreign keys to various tables that point to the "projects" table

See merge request !9388

app/models/appearance.rb

@@ -10,5 +10,5 @@ class Appearance < ActiveRecord::Base
 
   mount_uploader :logo,         AttachmentUploader
   mount_uploader :header_logo,  AttachmentUploader
-  has_many :uploads, as: :model, dependent: :destroy
+  has_many :uploads, as: :model, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 end

app/models/application_setting.rb

@@ -13,13 +13,13 @@ class ApplicationSetting < ActiveRecord::Base
                             [\r\n]          # any number of newline characters
                           }x
 
-  serialize :restricted_visibility_levels # rubocop:disable Cop/ActiverecordSerialize
-  serialize :import_sources # rubocop:disable Cop/ActiverecordSerialize
-  serialize :disabled_oauth_sign_in_sources, Array # rubocop:disable Cop/ActiverecordSerialize
-  serialize :domain_whitelist, Array # rubocop:disable Cop/ActiverecordSerialize
-  serialize :domain_blacklist, Array # rubocop:disable Cop/ActiverecordSerialize
-  serialize :repository_storages # rubocop:disable Cop/ActiverecordSerialize
-  serialize :sidekiq_throttling_queues, Array # rubocop:disable Cop/ActiverecordSerialize
+  serialize :restricted_visibility_levels # rubocop:disable Cop/ActiveRecordSerialize
+  serialize :import_sources # rubocop:disable Cop/ActiveRecordSerialize
+  serialize :disabled_oauth_sign_in_sources, Array # rubocop:disable Cop/ActiveRecordSerialize
+  serialize :domain_whitelist, Array # rubocop:disable Cop/ActiveRecordSerialize
+  serialize :domain_blacklist, Array # rubocop:disable Cop/ActiveRecordSerialize
+  serialize :repository_storages # rubocop:disable Cop/ActiveRecordSerialize
+  serialize :sidekiq_throttling_queues, Array # rubocop:disable Cop/ActiveRecordSerialize
 
   cache_markdown_field :sign_in_text
   cache_markdown_field :help_page_text

app/models/audit_event.rb

 class AuditEvent < ActiveRecord::Base
-  serialize :details, Hash # rubocop:disable Cop/ActiverecordSerialize
+  serialize :details, Hash # rubocop:disable Cop/ActiveRecordSerialize
 
   belongs_to :user, foreign_key: :author_id
 

app/models/board.rb

 class Board < ActiveRecord::Base
   belongs_to :project
 
-  has_many :lists, -> { order(:list_type, :position) }, dependent: :delete_all
+  has_many :lists, -> { order(:list_type, :position) }, dependent: :delete_all # rubocop:disable Cop/ActiveRecordDependent
 
   validates :project, presence: true
 

app/models/ci/build.rb

@@ -19,8 +19,8 @@ module Ci
       )
     end
 
-    serialize :options # rubocop:disable Cop/ActiverecordSerialize
-    serialize :yaml_variables, Gitlab::Serializer::Ci::Variables # rubocop:disable Cop/ActiverecordSerialize
+    serialize :options # rubocop:disable Cop/ActiveRecordSerialize
+    serialize :yaml_variables, Gitlab::Serializer::Ci::Variables # rubocop:disable Cop/ActiveRecordSerialize
 
     delegate :name, to: :project, prefix: true
 

app/models/ci/pipeline.rb

@@ -14,7 +14,7 @@ module Ci
     has_many :stages
     has_many :statuses, class_name: 'CommitStatus', foreign_key: :commit_id
     has_many :builds, foreign_key: :commit_id
-    has_many :trigger_requests, dependent: :destroy, foreign_key: :commit_id
+    has_many :trigger_requests, dependent: :destroy, foreign_key: :commit_id # rubocop:disable Cop/ActiveRecordDependent
 
     # Merge requests for which the current pipeline is running against
     # the merge request's latest commit.

app/models/ci/runner.rb

@@ -8,7 +8,7 @@ module Ci
     FORM_EDITABLE = %i[description tag_list active run_untagged locked].freeze
 
     has_many :builds
-    has_many :runner_projects, dependent: :destroy
+    has_many :runner_projects, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
     has_many :projects, through: :runner_projects
 
     has_one :last_build, ->() { order('id DESC') }, class_name: 'Ci::Build'

app/models/ci/trigger_request.rb

@@ -6,7 +6,7 @@ module Ci
     belongs_to :pipeline, foreign_key: :commit_id
     has_many :builds
 
-    serialize :variables # rubocop:disable Cop/ActiverecordSerialize
+    serialize :variables # rubocop:disable Cop/ActiveRecordSerialize
 
     def user_variables
       return [] unless variables

app/models/concerns/awardable.rb

@@ -2,7 +2,7 @@ module Awardable
   extend ActiveSupport::Concern
 
   included do
-    has_many :award_emoji, -> { includes(:user).order(:id) }, as: :awardable, dependent: :destroy
+    has_many :award_emoji, -> { includes(:user).order(:id) }, as: :awardable, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
     if self < Participable
       # By default we always load award_emoji user association

app/models/concerns/issuable.rb

@@ -30,7 +30,7 @@ module Issuable
     belongs_to :updated_by, class_name: "User"
     belongs_to :last_edited_by, class_name: 'User'
     belongs_to :milestone
-    has_many :notes, as: :noteable, inverse_of: :noteable, dependent: :destroy do
+    has_many :notes, as: :noteable, inverse_of: :noteable, dependent: :destroy do # rubocop:disable Cop/ActiveRecordDependent
       def authors_loaded?
         # We check first if we're loaded to not load unnecessarily.
         loaded? && to_a.all? { |note| note.association(:author).loaded? }
@@ -42,9 +42,9 @@ module Issuable
       end
     end
 
-    has_many :label_links, as: :target, dependent: :destroy
+    has_many :label_links, as: :target, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
     has_many :labels, through: :label_links
-    has_many :todos, as: :target, dependent: :destroy
+    has_many :todos, as: :target, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
     has_one :metrics
 

app/models/concerns/protected_ref.rb

@@ -17,7 +17,7 @@ module ProtectedRef
   class_methods do
     def protected_ref_access_levels(*types)
       types.each do |type|
-        has_many :"#{type}_access_levels", dependent: :destroy
+        has_many :"#{type}_access_levels", dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
         validates :"#{type}_access_levels", length: { is: 1, message: "are restricted to a single instance per #{self.model_name.human}." }
 

app/models/concerns/routable.rb

@@ -4,8 +4,8 @@ module Routable
   extend ActiveSupport::Concern
 
   included do
-    has_one :route, as: :source, autosave: true, dependent: :destroy
-    has_many :redirect_routes, as: :source, autosave: true, dependent: :destroy
+    has_one :route, as: :source, autosave: true, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
+    has_many :redirect_routes, as: :source, autosave: true, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
     validates_associated :route
     validates :route, presence: true

app/models/concerns/spammable.rb

@@ -8,7 +8,7 @@ module Spammable
   end
 
   included do
-    has_one :user_agent_detail, as: :subject, dependent: :destroy
+    has_one :user_agent_detail, as: :subject, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
     attr_accessor :spam
     attr_accessor :spam_log

app/models/concerns/subscribable.rb

@@ -9,7 +9,7 @@ module Subscribable
   extend ActiveSupport::Concern
 
   included do
-    has_many :subscriptions, dependent: :destroy, as: :subscribable
+    has_many :subscriptions, dependent: :destroy, as: :subscribable # rubocop:disable Cop/ActiveRecordDependent
   end
 
   def subscribed?(user, project = nil)

app/models/concerns/time_trackable.rb

@@ -18,7 +18,7 @@ module TimeTrackable
     validates :time_estimate, numericality: { message: 'has an invalid format' }, allow_nil: false
     validate  :check_negative_time_spent
 
-    has_many :timelogs, dependent: :destroy
+    has_many :timelogs, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
   end
 
   def spend_time(options)

app/models/deploy_key.rb

 class DeployKey < Key
-  has_many :deploy_keys_projects, dependent: :destroy
+  has_many :deploy_keys_projects, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
   has_many :projects, through: :deploy_keys_projects
 
   scope :in_projects, ->(projects) { joins(:deploy_keys_projects).where('deploy_keys_projects.project_id in (?)', projects) }

app/models/diff_note.rb

@@ -6,9 +6,9 @@ class DiffNote < Note
 
   NOTEABLE_TYPES = %w(MergeRequest Commit).freeze
 
-  serialize :original_position, Gitlab::Diff::Position # rubocop:disable Cop/ActiverecordSerialize
-  serialize :position, Gitlab::Diff::Position # rubocop:disable Cop/ActiverecordSerialize
-  serialize :change_position, Gitlab::Diff::Position # rubocop:disable Cop/ActiverecordSerialize
+  serialize :original_position, Gitlab::Diff::Position # rubocop:disable Cop/ActiveRecordSerialize
+  serialize :position, Gitlab::Diff::Position # rubocop:disable Cop/ActiveRecordSerialize
+  serialize :change_position, Gitlab::Diff::Position # rubocop:disable Cop/ActiveRecordSerialize
 
   validates :original_position, presence: true
   validates :position, presence: true

app/models/environment.rb

@@ -6,7 +6,7 @@ class Environment < ActiveRecord::Base
 
   belongs_to :project, required: true, validate: true
 
-  has_many :deployments, dependent: :destroy
+  has_many :deployments, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
   has_one :last_deployment, -> { order('deployments.id DESC') }, class_name: 'Deployment'
 
   before_validation :nullify_external_url

app/models/event.rb

@@ -50,7 +50,7 @@ class Event < ActiveRecord::Base
   belongs_to :target, polymorphic: true # rubocop:disable Cop/PolymorphicAssociations
 
   # For Hash only
-  serialize :data # rubocop:disable Cop/ActiverecordSerialize
+  serialize :data # rubocop:disable Cop/ActiveRecordSerialize
 
   # Callbacks
   after_create :reset_project_activity

app/models/group.rb

@@ -8,7 +8,7 @@ class Group < Namespace
   include Referable
   include SelectForProjectAuthorization
 
-  has_many :group_members, -> { where(requested_at: nil) }, dependent: :destroy, as: :source
+  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 :owners,
@@ -16,11 +16,11 @@ class Group < Namespace
     through: :group_members,
     source: :user
 
-  has_many :requesters, -> { where.not(requested_at: nil) }, dependent: :destroy, as: :source, class_name: 'GroupMember'
+  has_many :requesters, -> { where.not(requested_at: nil) }, dependent: :destroy, as: :source, class_name: 'GroupMember' # rubocop:disable Cop/ActiveRecordDependent
 
-  has_many :project_group_links, dependent: :destroy
+  has_many :project_group_links, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
   has_many :shared_projects, through: :project_group_links, source: :project
-  has_many :notification_settings, dependent: :destroy, as: :source
+  has_many :notification_settings, dependent: :destroy, as: :source # rubocop:disable Cop/ActiveRecordDependent
   has_many :labels, class_name: 'GroupLabel'
 
   validate :avatar_type, if: ->(user) { user.avatar.present? && user.avatar_changed? }
@@ -31,7 +31,7 @@ class Group < Namespace
   validates :two_factor_grace_period, presence: true, numericality: { greater_than_or_equal_to: 0 }
 
   mount_uploader :avatar, AvatarUploader
-  has_many :uploads, as: :model, dependent: :destroy
+  has_many :uploads, as: :model, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
   after_create :post_create_hook
   after_destroy :post_destroy_hook

app/models/hooks/web_hook.rb

@@ -12,7 +12,7 @@ class WebHook < ActiveRecord::Base
   default_value_for :repository_update_events, false
   default_value_for :enable_ssl_verification, true
 
-  has_many :web_hook_logs, dependent: :destroy
+  has_many :web_hook_logs, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
   scope :push_hooks, -> { where(push_events: true) }
   scope :tag_push_hooks, -> { where(tag_push_events: true) }

app/models/hooks/web_hook_log.rb

 class WebHookLog < ActiveRecord::Base
   belongs_to :web_hook
 
-  serialize :request_headers, Hash # rubocop:disable Cop/ActiverecordSerialize
-  serialize :request_data, Hash # rubocop:disable Cop/ActiverecordSerialize
-  serialize :response_headers, Hash # rubocop:disable Cop/ActiverecordSerialize
+  serialize :request_headers, Hash # rubocop:disable Cop/ActiveRecordSerialize
+  serialize :request_data, Hash # rubocop:disable Cop/ActiveRecordSerialize
+  serialize :response_headers, Hash # rubocop:disable Cop/ActiveRecordSerialize
 
   validates :web_hook, presence: true
 

app/models/issue.rb

@@ -23,9 +23,14 @@ class Issue < ActiveRecord::Base
   belongs_to :project
   belongs_to :moved_to, class_name: 'Issue'
 
-  has_many :events, as: :target, dependent: :destroy
+  has_many :events, as: :target, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
-  has_many :merge_requests_closing_issues, class_name: 'MergeRequestsClosingIssues', dependent: :delete_all
+  has_many :merge_requests_closing_issues,
+    class_name: 'MergeRequestsClosingIssues',
+    dependent: :delete_all # rubocop:disable Cop/ActiveRecordDependent
+
+  has_many :issue_assignees
+  has_many :assignees, class_name: "User", through: :issue_assignees
 
   has_many :issue_assignees
   has_many :assignees, class_name: "User", through: :issue_assignees

app/models/label.rb

@@ -15,9 +15,9 @@ class Label < ActiveRecord::Base
 
   default_value_for :color, DEFAULT_COLOR
 
-  has_many :lists, dependent: :destroy
+  has_many :lists, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
   has_many :priorities, class_name: 'LabelPriority'
-  has_many :label_links, dependent: :destroy
+  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'
 

app/models/legacy_diff_note.rb

@@ -7,7 +7,7 @@
 class LegacyDiffNote < Note
   include NoteOnDiff
 
-  serialize :st_diff # rubocop:disable Cop/ActiverecordSerialize
+  serialize :st_diff # rubocop:disable Cop/ActiveRecordSerialize
 
   validates :line_code, presence: true, line_code: true
 

app/models/lfs_object.rb

 class LfsObject < ActiveRecord::Base
-  has_many :lfs_objects_projects, dependent: :destroy
+  has_many :lfs_objects_projects, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
   has_many :projects, through: :lfs_objects_projects
 
   validates :oid, presence: true, uniqueness: true

app/models/merge_request.rb

@@ -12,19 +12,21 @@ class MergeRequest < ActiveRecord::Base
   belongs_to :source_project, class_name: "Project"
   belongs_to :merge_user, class_name: "User"
 
-  has_many :merge_request_diffs, dependent: :destroy
+  has_many :merge_request_diffs
   has_one :merge_request_diff,
     -> { order('merge_request_diffs.id DESC') }
 
   belongs_to :head_pipeline, foreign_key: "head_pipeline_id", class_name: "Ci::Pipeline"
 
-  has_many :events, as: :target, dependent: :destroy
+  has_many :events, as: :target, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
-  has_many :merge_requests_closing_issues, class_name: 'MergeRequestsClosingIssues', dependent: :delete_all
+  has_many :merge_requests_closing_issues,
+    class_name: 'MergeRequestsClosingIssues',
+    dependent: :delete_all # rubocop:disable Cop/ActiveRecordDependent
 
   belongs_to :assignee, class_name: "User"
 
-  serialize :merge_params, Hash # rubocop:disable Cop/ActiverecordSerialize
+  serialize :merge_params, Hash # rubocop:disable Cop/ActiveRecordSerialize
 
   after_create :ensure_merge_request_diff, unless: :importing?
   after_update :reload_diff_if_branch_changed

app/models/merge_request_diff.rb

@@ -12,8 +12,8 @@ class MergeRequestDiff < ActiveRecord::Base
   belongs_to :merge_request
   has_many :merge_request_diff_files, -> { order(:merge_request_diff_id, :relative_order) }
 
-  serialize :st_commits # rubocop:disable Cop/ActiverecordSerialize
-  serialize :st_diffs # rubocop:disable Cop/ActiverecordSerialize
+  serialize :st_commits # rubocop:disable Cop/ActiveRecordSerialize
+  serialize :st_diffs # rubocop:disable Cop/ActiveRecordSerialize
 
   state_machine :state, initial: :empty do
     state :collected

app/models/milestone.rb

@@ -21,7 +21,7 @@ class Milestone < ActiveRecord::Base
   has_many :issues
   has_many :labels, -> { distinct.reorder('labels.title') },  through: :issues
   has_many :merge_requests
-  has_many :events, as: :target, dependent: :destroy
+  has_many :events, as: :target, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
   scope :active, -> { with_state(:active) }
   scope :closed, -> { with_state(:closed) }

app/models/namespace.rb

@@ -15,13 +15,13 @@ class Namespace < ActiveRecord::Base
 
   cache_markdown_field :description, pipeline: :description
 
-  has_many :projects, dependent: :destroy
+  has_many :projects, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
   has_many :project_statistics
   belongs_to :owner, class_name: "User"
 
   belongs_to :parent, class_name: "Namespace"
   has_many :children, class_name: "Namespace", foreign_key: :parent_id
-  has_one :chat_team, dependent: :destroy
+  has_one :chat_team, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
   validates :owner, presence: true, unless: ->(n) { n.type == "Group" }
   validates :name,

app/models/note.rb

@@ -46,8 +46,8 @@ class Note < ActiveRecord::Base
   belongs_to :updated_by, class_name: "User"
   belongs_to :last_edited_by, class_name: 'User'
 
-  has_many :todos, dependent: :destroy
-  has_many :events, as: :target, dependent: :destroy
+  has_many :todos, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
+  has_many :events, as: :target, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
   has_one :system_note_metadata
 
   delegate :gfm_reference, :local_reference, to: :noteable

app/models/personal_access_token.rb

@@ -3,7 +3,7 @@ class PersonalAccessToken < ActiveRecord::Base
   include TokenAuthenticatable
   add_authentication_token_field :token
 
-  serialize :scopes, Array # rubocop:disable Cop/ActiverecordSerialize
+  serialize :scopes, Array # rubocop:disable Cop/ActiveRecordSerialize
 
   belongs_to :user
 

app/models/project.rb

@@ -59,6 +59,7 @@ class Project < ActiveRecord::Base
     update_column(:last_repository_updated_at, self.created_at)
   end
 
+  before_destroy :remove_private_deploy_keys
   after_destroy :remove_pages
 
   # update visibility_level of forks
@@ -80,96 +81,108 @@ class Project < ActiveRecord::Base
   belongs_to :namespace
 
   has_one :last_event, -> {order 'events.created_at DESC'}, class_name: 'Event'
-  has_many :boards, before_add: :validate_board_limit, dependent: :destroy
+  has_many :boards, before_add: :validate_board_limit
 
   # Project services
-  has_one :campfire_service, dependent: :destroy
-  has_one :drone_ci_service, dependent: :destroy
-  has_one :emails_on_push_service, dependent: :destroy
-  has_one :pipelines_email_service, dependent: :destroy
-  has_one :irker_service, dependent: :destroy
-  has_one :pivotaltracker_service, dependent: :destroy
-  has_one :hipchat_service, dependent: :destroy
-  has_one :flowdock_service, dependent: :destroy
-  has_one :assembla_service, dependent: :destroy
-  has_one :asana_service, dependent: :destroy
-  has_one :gemnasium_service, dependent: :destroy
-  has_one :mattermost_slash_commands_service, dependent: :destroy
-  has_one :mattermost_service, dependent: :destroy
-  has_one :slack_slash_commands_service, dependent: :destroy
-  has_one :slack_service, dependent: :destroy
-  has_one :buildkite_service, dependent: :destroy
-  has_one :bamboo_service, dependent: :destroy
-  has_one :teamcity_service, dependent: :destroy
-  has_one :pushover_service, dependent: :destroy
-  has_one :jira_service, dependent: :destroy
-  has_one :redmine_service, dependent: :destroy
-  has_one :custom_issue_tracker_service, dependent: :destroy
-  has_one :bugzilla_service, dependent: :destroy
-  has_one :gitlab_issue_tracker_service, dependent: :destroy, inverse_of: :project
-  has_one :external_wiki_service, dependent: :destroy
-  has_one :kubernetes_service, dependent: :destroy, inverse_of: :project
-  has_one :prometheus_service, dependent: :destroy, inverse_of: :project
-  has_one :mock_ci_service, dependent: :destroy
-  has_one :mock_deployment_service, dependent: :destroy
-  has_one :mock_monitoring_service, dependent: :destroy
-  has_one :microsoft_teams_service, dependent: :destroy
-
-  has_one  :forked_project_link,  dependent: :destroy, foreign_key: "forked_to_project_id"
+  has_one :campfire_service
+  has_one :drone_ci_service
+  has_one :emails_on_push_service
+  has_one :pipelines_email_service
+  has_one :irker_service
+  has_one :pivotaltracker_service
+  has_one :hipchat_service
+  has_one :flowdock_service
+  has_one :assembla_service
+  has_one :asana_service
+  has_one :gemnasium_service
+  has_one :mattermost_slash_commands_service
+  has_one :mattermost_service
+  has_one :slack_slash_commands_service
+  has_one :slack_service
+  has_one :buildkite_service
+  has_one :bamboo_service
+  has_one :teamcity_service
+  has_one :pushover_service
+  has_one :jira_service
+  has_one :redmine_service
+  has_one :custom_issue_tracker_service
+  has_one :bugzilla_service
+  has_one :gitlab_issue_tracker_service, inverse_of: :project
+  has_one :external_wiki_service
+  has_one :kubernetes_service, inverse_of: :project
+  has_one :prometheus_service, inverse_of: :project
+  has_one :mock_ci_service
+  has_one :mock_deployment_service
+  has_one :mock_monitoring_service
+  has_one :microsoft_teams_service
+
+  has_one  :forked_project_link,  foreign_key: "forked_to_project_id"
   has_one  :forked_from_project,  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
 
   # Merge Requests for target project should be removed with it
-  has_many :merge_requests,     dependent: :destroy, foreign_key: 'target_project_id'
-  has_many :issues,             dependent: :destroy
-  has_many :labels,             dependent: :destroy, class_name: 'ProjectLabel'
-  has_many :services,           dependent: :destroy
-  has_many :events,             dependent: :destroy
-  has_many :milestones,         dependent: :destroy
-  has_many :notes,              dependent: :destroy
-  has_many :snippets,           dependent: :destroy, class_name: 'ProjectSnippet'
-  has_many :hooks,              dependent: :destroy, class_name: 'ProjectHook'
-  has_many :protected_branches, dependent: :destroy
-  has_many :protected_tags,     dependent: :destroy
+  has_many :merge_requests, foreign_key: 'target_project_id'
+  has_many :issues
+  has_many :labels, class_name: 'ProjectLabel'
+  has_many :services
+  has_many :events
+  has_many :milestones
+  has_many :notes
+  has_many :snippets, class_name: 'ProjectSnippet'
+  has_many :hooks, class_name: 'ProjectHook'
+  has_many :protected_branches
+  has_many :protected_tags
 
   has_many :project_authorizations
   has_many :authorized_users, through: :project_authorizations, source: :user, class_name: 'User'
-  has_many :project_members, -> { where(requested_at: nil) }, dependent: :destroy, as: :source
+  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 :requesters, -> { where.not(requested_at: nil) }, dependent: :destroy, as: :source, class_name: 'ProjectMember'
+  has_many :requesters, -> { where.not(requested_at: nil) },
+    as: :source, class_name: 'ProjectMember', dependent: :delete_all # rubocop:disable Cop/ActiveRecordDependent
 
-  has_many :deploy_keys_projects, dependent: :destroy
+  has_many :deploy_keys_projects
   has_many :deploy_keys, through: :deploy_keys_projects
-  has_many :users_star_projects, dependent: :destroy
+  has_many :users_star_projects
   has_many :starrers, through: :users_star_projects, source: :user
-  has_many :releases, dependent: :destroy
-  has_many :lfs_objects_projects, dependent: :destroy
+  has_many :releases
+  has_many :lfs_objects_projects, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
   has_many :lfs_objects, through: :lfs_objects_projects
-  has_many :project_group_links, dependent: :destroy
+  has_many :project_group_links
   has_many :invited_groups, through: :project_group_links, source: :group
-  has_many :pages_domains, dependent: :destroy
-  has_many :todos, dependent: :destroy
-  has_many :notification_settings, dependent: :destroy, as: :source
-
-  has_one :import_data, dependent: :delete, class_name: 'ProjectImportData'
-  has_one :project_feature, dependent: :destroy
-  has_one :statistics, class_name: 'ProjectStatistics', dependent: :delete
-  has_many :container_repositories, dependent: :destroy
-
-  has_many :commit_statuses, dependent: :destroy
-  has_many :pipelines, dependent: :destroy, class_name: 'Ci::Pipeline'
-  has_many :builds, class_name: 'Ci::Build' # the builds are created from the commit_statuses
-  has_many :runner_projects, dependent: :destroy, class_name: 'Ci::RunnerProject'
+  has_many :pages_domains
+  has_many :todos
+  has_many :notification_settings, as: :source, dependent: :delete_all # rubocop:disable Cop/ActiveRecordDependent
+
+  has_one :import_data, class_name: 'ProjectImportData'
+  has_one :project_feature
+  has_one :statistics, class_name: 'ProjectStatistics'
+
+  # Container repositories need to remove data from the container registry,
+  # which is not managed by the DB. Hence we're still using dependent: :destroy
+  # here.
+  has_many :container_repositories, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
+
+  has_many :commit_statuses
+  has_many :pipelines, class_name: 'Ci::Pipeline'
+
+  # Ci::Build objects store data on the file system such as artifact files and
+  # build traces. Currently there's no efficient way of removing this data in
+  # bulk that doesn't involve loading the rows into memory. As a result we're
+  # still using `dependent: :destroy` here.
+  has_many :builds, class_name: 'Ci::Build', dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
+  has_many :runner_projects, class_name: 'Ci::RunnerProject'
   has_many :runners, through: :runner_projects, source: :runner, class_name: 'Ci::Runner'
   has_many :variables, class_name: 'Ci::Variable'
-  has_many :triggers, dependent: :destroy, class_name: 'Ci::Trigger'
-  has_many :environments, dependent: :destroy
-  has_many :deployments, dependent: :destroy
-  has_many :pipeline_schedules, dependent: :destroy, class_name: 'Ci::PipelineSchedule'
+  has_many :triggers, class_name: 'Ci::Trigger'
+  has_many :environments
+  has_many :deployments
+  has_many :pipeline_schedules, class_name: 'Ci::PipelineSchedule'
 
   has_many :active_runners, -> { active }, through: :runner_projects, source: :runner, class_name: 'Ci::Runner'
 
@@ -224,7 +237,7 @@ class Project < ActiveRecord::Base
   before_save :ensure_runners_token
 
   mount_uploader :avatar, AvatarUploader
-  has_many :uploads, as: :model, dependent: :destroy
+  has_many :uploads, as: :model, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
   # Scopes
   scope :pending_delete, -> { where(pending_delete: true) }
@@ -1240,7 +1253,13 @@ class Project < ActiveRecord::Base
     File.join(pages_path, 'public')
   end
 
+  def remove_private_deploy_keys
+    deploy_keys.where(public: false).delete_all
+  end
+
   def remove_pages
+    ::Projects::UpdatePagesConfigurationService.new(self).execute
+
     # 1. We rename pages to temporary directory
     # 2. We wait 5 minutes, due to NFS caching
     # 3. We asynchronously remove pages with force

app/models/project_import_data.rb

@@ -10,7 +10,7 @@ class ProjectImportData < ActiveRecord::Base
                  insecure_mode: true,
                  algorithm: 'aes-256-cbc'
 
-  serialize :data, JSON # rubocop:disable Cop/ActiverecordSerialize
+  serialize :data, JSON # rubocop:disable Cop/ActiveRecordSerialize
 
   validates :project, presence: true
 

app/models/project_services/slash_commands_service.rb

@@ -5,7 +5,7 @@ class SlashCommandsService < Service
 
   prop_accessor :token
 
-  has_many :chat_names, foreign_key: :service_id, dependent: :destroy
+  has_many :chat_names, foreign_key: :service_id, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
   def valid_token?(token)
     self.respond_to?(:token) &&

app/models/sent_notification.rb

 class SentNotification < ActiveRecord::Base
-  serialize :position, Gitlab::Diff::Position # rubocop:disable Cop/ActiverecordSerialize
+  serialize :position, Gitlab::Diff::Position # rubocop:disable Cop/ActiveRecordSerialize
 
   belongs_to :project
   belongs_to :noteable, polymorphic: true # rubocop:disable Cop/PolymorphicAssociations

app/models/service.rb

@@ -2,7 +2,7 @@
 # and implement a set of methods
 class Service < ActiveRecord::Base
   include Sortable
-  serialize :properties, JSON # rubocop:disable Cop/ActiverecordSerialize
+  serialize :properties, JSON # rubocop:disable Cop/ActiveRecordSerialize
 
   default_value_for :active, false
   default_value_for :push_events, true

app/models/snippet.rb

@@ -30,7 +30,7 @@ class Snippet < ActiveRecord::Base
   belongs_to :author, class_name: 'User'
   belongs_to :project
 
-  has_many :notes, as: :noteable, dependent: :destroy
+  has_many :notes, as: :noteable, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
   delegate :name, :email, to: :author, prefix: true, allow_nil: true
 

app/models/user.rb

@@ -41,7 +41,7 @@ class User < ActiveRecord::Base
          otp_secret_encryption_key: Gitlab::Application.secrets.otp_key_base
 
   devise :two_factor_backupable, otp_number_of_backup_codes: 10
-  serialize :otp_backup_codes, JSON # rubocop:disable Cop/ActiverecordSerialize
+  serialize :otp_backup_codes, JSON # rubocop:disable Cop/ActiveRecordSerialize
 
   devise :lockable, :recoverable, :rememberable, :trackable,
     :validatable, :omniauthable, :confirmable, :registerable
@@ -67,24 +67,24 @@ class User < ActiveRecord::Base
   #
 
   # Namespace for personal projects
-  has_one :namespace, -> { where type: nil }, dependent: :destroy, foreign_key: :owner_id, autosave: true
+  has_one :namespace, -> { where type: nil }, dependent: :destroy, foreign_key: :owner_id, autosave: true # rubocop:disable Cop/ActiveRecordDependent
 
   # Profile
   has_many :keys, -> do
     type = Key.arel_table[:type]
     where(type.not_eq('DeployKey').or(type.eq(nil)))
-  end, dependent: :destroy
-  has_many :deploy_keys, -> { where(type: 'DeployKey') }, dependent: :destroy
+  end, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
+  has_many :deploy_keys, -> { where(type: 'DeployKey') }, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
-  has_many :emails, dependent: :destroy
-  has_many :personal_access_tokens, dependent: :destroy
-  has_many :identities, dependent: :destroy, autosave: true
-  has_many :u2f_registrations, dependent: :destroy
-  has_many :chat_names, dependent: :destroy
+  has_many :emails, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
+  has_many :personal_access_tokens, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
+  has_many :identities, dependent: :destroy, autosave: true # rubocop:disable Cop/ActiveRecordDependent
+  has_many :u2f_registrations, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
+  has_many :chat_names, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
   # Groups
-  has_many :members, dependent: :destroy
-  has_many :group_members, -> { where(requested_at: nil) }, dependent: :destroy, source: 'GroupMember'
+  has_many :members, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
+  has_many :group_members, -> { where(requested_at: nil) }, dependent: :destroy, source: 'GroupMember' # rubocop:disable Cop/ActiveRecordDependent
   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
@@ -92,35 +92,35 @@ class User < ActiveRecord::Base
   # Projects
   has_many :groups_projects,          through: :groups, source: :projects
   has_many :personal_projects,        through: :namespace, source: :projects
-  has_many :project_members, -> { where(requested_at: nil) }, dependent: :destroy
+  has_many :project_members, -> { where(requested_at: nil) }, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
   has_many :projects,                 through: :project_members
   has_many :created_projects,         foreign_key: :creator_id, class_name: 'Project'
-  has_many :users_star_projects, dependent: :destroy
+  has_many :users_star_projects, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
   has_many :starred_projects, through: :users_star_projects, source: :project
   has_many :project_authorizations
   has_many :authorized_projects, through: :project_authorizations, source: :project
 
-  has_many :snippets,                 dependent: :destroy, foreign_key: :author_id
-  has_many :notes,                    dependent: :destroy, foreign_key: :author_id
-  has_many :issues,                   dependent: :destroy, foreign_key: :author_id
-  has_many :merge_requests,           dependent: :destroy, foreign_key: :author_id
-  has_many :events,                   dependent: :destroy, foreign_key: :author_id
-  has_many :subscriptions,            dependent: :destroy
+  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
+  has_many :issues,                   dependent: :destroy, foreign_key: :author_id # rubocop:disable Cop/ActiveRecordDependent
+  has_many :merge_requests,           dependent: :destroy, foreign_key: :author_id # rubocop:disable Cop/ActiveRecordDependent
+  has_many :events,                   dependent: :destroy, foreign_key: :author_id # rubocop:disable Cop/ActiveRecordDependent
+  has_many :subscriptions,            dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
   has_many :recent_events, -> { order "id DESC" }, foreign_key: :author_id,   class_name: "Event"
-  has_many :oauth_applications, class_name: 'Doorkeeper::Application', as: :owner, dependent: :destroy
-  has_one  :abuse_report,             dependent: :destroy, foreign_key: :user_id
-  has_many :reported_abuse_reports,   dependent: :destroy, foreign_key: :reporter_id, class_name: "AbuseReport"
-  has_many :spam_logs,                dependent: :destroy
-  has_many :builds,                   dependent: :nullify, class_name: 'Ci::Build'
-  has_many :pipelines,                dependent: :nullify, class_name: 'Ci::Pipeline'
-  has_many :todos,                    dependent: :destroy
-  has_many :notification_settings,    dependent: :destroy
-  has_many :award_emoji,              dependent: :destroy
-  has_many :triggers,                 dependent: :destroy, class_name: 'Ci::Trigger', foreign_key: :owner_id
+  has_many :oauth_applications, class_name: 'Doorkeeper::Application', as: :owner, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
+  has_one  :abuse_report,             dependent: :destroy, foreign_key: :user_id # rubocop:disable Cop/ActiveRecordDependent
+  has_many :reported_abuse_reports,   dependent: :destroy, foreign_key: :reporter_id, class_name: "AbuseReport" # rubocop:disable Cop/ActiveRecordDependent
+  has_many :spam_logs,                dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
+  has_many :builds,                   dependent: :nullify, class_name: 'Ci::Build' # rubocop:disable Cop/ActiveRecordDependent
+  has_many :pipelines,                dependent: :nullify, class_name: 'Ci::Pipeline' # rubocop:disable Cop/ActiveRecordDependent
+  has_many :todos,                    dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
+  has_many :notification_settings,    dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
+  has_many :award_emoji,              dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
+  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_merge_requests,  dependent: :nullify, foreign_key: :assignee_id, class_name: "MergeRequest"
+  has_many :assigned_merge_requests,  dependent: :nullify, foreign_key: :assignee_id, class_name: "MergeRequest" # rubocop:disable Cop/ActiveRecordDependent
 
   #
   # Validations
@@ -211,7 +211,7 @@ class User < ActiveRecord::Base
   end
 
   mount_uploader :avatar, AvatarUploader
-  has_many :uploads, as: :model, dependent: :destroy
+  has_many :uploads, as: :model, dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
 
   # Scopes
   scope :admins, -> { where(admin: true) }

changelogs/unreleased/foreign-keys-for-project-model.yml

+---
+title: Speed up project removals by adding foreign keys with cascading deletes to various tables
+merge_request:
+author:

db/migrate/20170530130129_project_foreign_keys_with_cascading_deletes.rb

+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class ProjectForeignKeysWithCascadingDeletes < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  DOWNTIME = false
+
+  CONCURRENCY = 4
+
+  disable_ddl_transaction!
+
+  # The tables/columns for which to remove orphans and add foreign keys. Order
+  # matters as some tables/columns should be processed before others.
+  TABLES = [
+    [:boards, :projects, :project_id],
+    [:lists, :labels, :label_id],
+    [:lists, :boards, :board_id],
+    [:services, :projects, :project_id],
+    [:forked_project_links, :projects, :forked_to_project_id],
+    [:merge_requests, :projects, :target_project_id],
+    [:labels, :projects, :project_id],
+    [:issues, :projects, :project_id],
+    [:events, :projects, :project_id],
+    [:milestones, :projects, :project_id],
+    [:notes, :projects, :project_id],
+    [:snippets, :projects, :project_id],
+    [:web_hooks, :projects, :project_id],
+    [:protected_branch_merge_access_levels, :protected_branches, :protected_branch_id],
+    [:protected_branch_push_access_levels, :protected_branches, :protected_branch_id],
+    [:protected_branches, :projects, :project_id],
+    [:protected_tags, :projects, :project_id],
+    [:deploy_keys_projects, :projects, :project_id],
+    [:users_star_projects, :projects, :project_id],
+    [:releases, :projects, :project_id],
+    [:project_group_links, :projects, :project_id],
+    [:pages_domains, :projects, :project_id],
+    [:todos, :projects, :project_id],
+    [:project_import_data, :projects, :project_id],
+    [:project_features, :projects, :project_id],
+    [:ci_builds, :projects, :project_id],
+    [:ci_pipelines, :projects, :project_id],
+    [:ci_runner_projects, :projects, :project_id],
+    [:ci_triggers, :projects, :project_id],
+    [:environments, :projects, :project_id],
+    [:deployments, :projects, :project_id]
+  ]
+
+  def up
+    # These existing foreign keys don't have an "ON DELETE CASCADE" clause.
+    remove_foreign_key_without_error(:boards, :project_id)
+    remove_foreign_key_without_error(:lists, :label_id)
+    remove_foreign_key_without_error(:lists, :board_id)
+    remove_foreign_key_without_error(:protected_branch_merge_access_levels,
+                                     :protected_branch_id)
+
+    remove_foreign_key_without_error(:protected_branch_push_access_levels,
+                                     :protected_branch_id)
+
+    remove_orphaned_rows
+    add_foreign_keys
+
+    # These columns are not indexed yet, meaning a cascading delete would take
+    # forever.
+    add_concurrent_index(:project_group_links, :project_id)
+    add_concurrent_index(:pages_domains, :project_id)
+  end
+
+  def down
+    TABLES.each do |(source, _, column)|
+      remove_foreign_key_without_error(source, column)
+    end
+
+    add_concurrent_foreign_key(:boards, :projects, column: :project_id)
+    add_concurrent_foreign_key(:lists, :labels, column: :label_id)
+    add_concurrent_foreign_key(:lists, :boards, column: :board_id)
+
+    add_concurrent_foreign_key(:protected_branch_merge_access_levels,
+                               :protected_branches,
+                               column: :protected_branch_id)
+
+    add_concurrent_foreign_key(:protected_branch_push_access_levels,
+                               :protected_branches,
+                               column: :protected_branch_id)
+
+    remove_index_without_error(:project_group_links, :project_id)
+    remove_index_without_error(:pages_domains, :project_id)
+  end
+
+  def add_foreign_keys
+    TABLES.each do |(source, target, column)|
+      add_concurrent_foreign_key(source, target, column: column)
+    end
+  end
+
+  # Removes orphans from various tables concurrently.
+  def remove_orphaned_rows
+    Gitlab::Database.with_connection_pool(CONCURRENCY) do |pool|
+      queues = queues_for_rows(TABLES)
+
+      threads = queues.map do |queue|
+        Thread.new do
+          pool.with_connection do |connection|
+            Thread.current[:foreign_key_connection] = connection
+
+            # Disables statement timeouts for the current connection. This is
+            # necessary as removing of orphaned data might otherwise exceed the
+            # statement timeout.
+            disable_statement_timeout
+
+            remove_orphans(*queue.pop) until queue.empty?
+
+            steal_from_queues(queues - [queue])
+          end
+        end
+      end
+
+      threads.each(&:join)
+    end
+  end
+
+  def steal_from_queues(queues)
+    loop do
+      stolen = false
+
+      queues.each do |queue|
+        # Stealing is racy so it's possible a pop might be called on an
+        # already-empty queue.
+        begin
+          remove_orphans(*queue.pop(true))
+          stolen = true
+        rescue ThreadError
+        end
+      end
+
+      break unless stolen
+    end
+  end
+
+  def remove_orphans(source, target, column)
+    quoted_source = quote_table_name(source)
+    quoted_target = quote_table_name(target)
+    quoted_column = quote_column_name(column)
+
+    execute <<-EOF.strip_heredoc
+    DELETE FROM #{quoted_source}
+    WHERE NOT EXISTS (
+      SELECT true
+      FROM #{quoted_target}
+      WHERE #{quoted_target}.id = #{quoted_source}.#{quoted_column}
+    )
+    AND #{quoted_source}.#{quoted_column} IS NOT NULL
+    EOF
+  end
+
+  def remove_foreign_key_without_error(table, column)
+    remove_foreign_key(table, column: column)
+  rescue ArgumentError
+  end
+
+  def remove_index_without_error(table, column)
+    remove_concurrent_index(table, column)
+  rescue ArgumentError
+  end
+
+  def connection
+    # Rails memoizes connection objects, but this causes them to be shared
+    # amongst threads; we don't want that.
+    Thread.current[:foreign_key_connection] || ActiveRecord::Base.connection
+  end
+
+  def queues_for_rows(rows)
+    queues = Array.new(CONCURRENCY) { Queue.new }
+    slice_size = rows.length / CONCURRENCY
+
+    # Divide all the tuples as evenly as possible amongst the queues.
+    rows.each_slice(slice_size).each_with_index do |slice, index|
+      bucket = index % CONCURRENCY
+
+      slice.each do |row|
+        queues[bucket] << row
+      end
+    end
+
+    queues
+  end
+end

db/migrate/20170622130029_correct_protected_branches_foreign_keys.rb

+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class CorrectProtectedBranchesForeignKeys < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  # Set this constant to true if this migration requires downtime.
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    remove_foreign_key_without_error(:protected_branch_push_access_levels,
+                                     column: :protected_branch_id)
+
+    execute <<-EOF
+    DELETE FROM protected_branch_push_access_levels
+    WHERE NOT EXISTS (
+      SELECT true
+      FROM protected_branches
+      WHERE protected_branch_push_access_levels.protected_branch_id = protected_branches.id
+    )
+    AND protected_branch_id IS NOT NULL
+    EOF
+
+    add_concurrent_foreign_key(:protected_branch_push_access_levels,
+                               :protected_branches,
+                               column: :protected_branch_id)
+  end
+
+  def down
+    # Previously there was a foreign key without a CASCADING DELETE, so we'll
+    # just leave the foreign key in place.
+  end
+
+  def remove_foreign_key_without_error(*args)
+    remove_foreign_key(*args)
+  rescue ArgumentError
+  end
+end

db/migrate/20170622132212_add_foreign_key_for_merge_request_diffs.rb

+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class AddForeignKeyForMergeRequestDiffs < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  # Set this constant to true if this migration requires downtime.
+  DOWNTIME = false
+
+  disable_ddl_transaction!
+
+  def up
+    execute <<-EOF
+    DELETE FROM merge_request_diffs
+    WHERE NOT EXISTS (
+      SELECT true
+      FROM merge_requests
+      WHERE merge_requests.id = merge_request_diffs.merge_request_id
+    )
+    EOF
+
+    add_concurrent_foreign_key(:merge_request_diffs,
+                               :merge_requests,
+                               column: :merge_request_id)
+  end
+
+  def down
+    remove_foreign_key(:merge_request_diffs, column: :merge_request_id)
+  end
+end

db/schema.rb

@@ -971,6 +971,7 @@ ActiveRecord::Schema.define(version: 20170703102400) do
   end
 
   add_index "pages_domains", ["domain"], name: "index_pages_domains_on_domain", unique: true, using: :btree
+  add_index "pages_domains", ["project_id"], name: "index_pages_domains_on_project_id", using: :btree
 
   create_table "personal_access_tokens", force: :cascade do |t|
     t.integer "user_id", null: false
@@ -1020,6 +1021,7 @@ ActiveRecord::Schema.define(version: 20170703102400) do
   end
 
   add_index "project_group_links", ["group_id"], name: "index_project_group_links_on_group_id", using: :btree
+  add_index "project_group_links", ["project_id"], name: "index_project_group_links_on_project_id", using: :btree
 
   create_table "project_import_data", force: :cascade do |t|
     t.integer "project_id"
@@ -1528,48 +1530,75 @@ ActiveRecord::Schema.define(version: 20170703102400) do
   add_index "web_hooks", ["project_id"], name: "index_web_hooks_on_project_id", using: :btree
   add_index "web_hooks", ["type"], name: "index_web_hooks_on_type", using: :btree
 
-  add_foreign_key "boards", "projects"
+  add_foreign_key "boards", "projects", name: "fk_f15266b5f9", on_delete: :cascade
   add_foreign_key "chat_teams", "namespaces", on_delete: :cascade
   add_foreign_key "ci_builds", "ci_pipelines", column: "auto_canceled_by_id", name: "fk_a2141b1522", on_delete: :nullify
   add_foreign_key "ci_builds", "ci_stages", column: "stage_id", name: "fk_3a9eaa254d", on_delete: :cascade
+  add_foreign_key "ci_builds", "projects", name: "fk_befce0568a", on_delete: :cascade
   add_foreign_key "ci_pipeline_schedules", "projects", name: "fk_8ead60fcc4", on_delete: :cascade
   add_foreign_key "ci_pipeline_schedules", "users", column: "owner_id", name: "fk_9ea99f58d2", on_delete: :nullify
   add_foreign_key "ci_pipelines", "ci_pipeline_schedules", column: "pipeline_schedule_id", name: "fk_3d34ab2e06", on_delete: :nullify
   add_foreign_key "ci_pipelines", "ci_pipelines", column: "auto_canceled_by_id", name: "fk_262d4c2d19", on_delete: :nullify
+  add_foreign_key "ci_pipelines", "projects", name: "fk_86635dbd80", on_delete: :cascade
+  add_foreign_key "ci_runner_projects", "projects", name: "fk_4478a6f1e4", on_delete: :cascade
   add_foreign_key "ci_stages", "ci_pipelines", column: "pipeline_id", name: "fk_fb57e6cc56", on_delete: :cascade
   add_foreign_key "ci_stages", "projects", name: "fk_2360681d1d", on_delete: :cascade
   add_foreign_key "ci_trigger_requests", "ci_triggers", column: "trigger_id", name: "fk_b8ec8b7245", on_delete: :cascade
+  add_foreign_key "ci_triggers", "projects", name: "fk_e3e63f966e", on_delete: :cascade
   add_foreign_key "ci_triggers", "users", column: "owner_id", name: "fk_e8e10d1964", on_delete: :cascade
   add_foreign_key "ci_variables", "projects", name: "fk_ada5eb64b3", on_delete: :cascade
   add_foreign_key "container_repositories", "projects"
+  add_foreign_key "deploy_keys_projects", "projects", name: "fk_58a901ca7e", on_delete: :cascade
+  add_foreign_key "deployments", "projects", name: "fk_b9a3851b82", on_delete: :cascade
+  add_foreign_key "environments", "projects", name: "fk_d1c8c1da6a", on_delete: :cascade
+  add_foreign_key "events", "projects", name: "fk_0434b48643", on_delete: :cascade
+  add_foreign_key "forked_project_links", "projects", column: "forked_to_project_id", name: "fk_434510edb0", on_delete: :cascade
   add_foreign_key "issue_assignees", "issues", name: "fk_b7d881734a", on_delete: :cascade
   add_foreign_key "issue_assignees", "users", name: "fk_5e0c8d9154", on_delete: :cascade
   add_foreign_key "issue_metrics", "issues", on_delete: :cascade
+  add_foreign_key "issues", "projects", name: "fk_899c8f3231", on_delete: :cascade
   add_foreign_key "label_priorities", "labels", on_delete: :cascade
   add_foreign_key "label_priorities", "projects", on_delete: :cascade
   add_foreign_key "labels", "namespaces", column: "group_id", on_delete: :cascade
-  add_foreign_key "lists", "boards"
-  add_foreign_key "lists", "labels"
+  add_foreign_key "labels", "projects", name: "fk_7de4989a69", on_delete: :cascade
+  add_foreign_key "lists", "boards", name: "fk_0d3f677137", on_delete: :cascade
+  add_foreign_key "lists", "labels", name: "fk_7a5553d60f", on_delete: :cascade
   add_foreign_key "merge_request_diff_files", "merge_request_diffs", on_delete: :cascade
+  add_foreign_key "merge_request_diffs", "merge_requests", name: "fk_8483f3258f", on_delete: :cascade
   add_foreign_key "merge_request_metrics", "ci_pipelines", column: "pipeline_id", on_delete: :cascade
   add_foreign_key "merge_request_metrics", "merge_requests", on_delete: :cascade
+  add_foreign_key "merge_requests", "projects", column: "target_project_id", name: "fk_a6963e8447", on_delete: :cascade
   add_foreign_key "merge_requests_closing_issues", "issues", on_delete: :cascade
   add_foreign_key "merge_requests_closing_issues", "merge_requests", on_delete: :cascade
+  add_foreign_key "milestones", "projects", name: "fk_9bd0a0c791", on_delete: :cascade
+  add_foreign_key "notes", "projects", name: "fk_99e097b079", on_delete: :cascade
   add_foreign_key "oauth_openid_requests", "oauth_access_grants", column: "access_grant_id", name: "fk_oauth_openid_requests_oauth_access_grants_access_grant_id"
+  add_foreign_key "pages_domains", "projects", name: "fk_ea2f6dfc6f", on_delete: :cascade
   add_foreign_key "personal_access_tokens", "users"
   add_foreign_key "project_authorizations", "projects", on_delete: :cascade
   add_foreign_key "project_authorizations", "users", on_delete: :cascade
+  add_foreign_key "project_features", "projects", name: "fk_18513d9b92", on_delete: :cascade
+  add_foreign_key "project_group_links", "projects", name: "fk_daa8cee94c", on_delete: :cascade
+  add_foreign_key "project_import_data", "projects", name: "fk_ffb9ee3a10", on_delete: :cascade
   add_foreign_key "project_statistics", "projects", on_delete: :cascade
-  add_foreign_key "protected_branch_merge_access_levels", "protected_branches"
-  add_foreign_key "protected_branch_push_access_levels", "protected_branches"
+  add_foreign_key "protected_branch_merge_access_levels", "protected_branches", name: "fk_8a3072ccb3", on_delete: :cascade
+  add_foreign_key "protected_branch_push_access_levels", "protected_branches", name: "fk_9ffc86a3d9", on_delete: :cascade
+  add_foreign_key "protected_branches", "projects", name: "fk_7a9c6d93e7", on_delete: :cascade
   add_foreign_key "protected_tag_create_access_levels", "namespaces", column: "group_id"
   add_foreign_key "protected_tag_create_access_levels", "protected_tags"
   add_foreign_key "protected_tag_create_access_levels", "users"
+  add_foreign_key "protected_tags", "projects", name: "fk_8e4af87648", on_delete: :cascade
+  add_foreign_key "releases", "projects", name: "fk_47fe2a0596", on_delete: :cascade
+  add_foreign_key "services", "projects", name: "fk_71cce407f9", on_delete: :cascade
+  add_foreign_key "snippets", "projects", name: "fk_be41fd4bb7", on_delete: :cascade
   add_foreign_key "subscriptions", "projects", on_delete: :cascade
   add_foreign_key "system_note_metadata", "notes", name: "fk_d83a918cb1", on_delete: :cascade
   add_foreign_key "timelogs", "issues", name: "fk_timelogs_issues_issue_id", on_delete: :cascade
   add_foreign_key "timelogs", "merge_requests", name: "fk_timelogs_merge_requests_merge_request_id", on_delete: :cascade
+  add_foreign_key "todos", "projects", name: "fk_45054f9c45", on_delete: :cascade
   add_foreign_key "trending_projects", "projects", on_delete: :cascade
   add_foreign_key "u2f_registrations", "users"
+  add_foreign_key "users_star_projects", "projects", name: "fk_22cd27ddfc", on_delete: :cascade
   add_foreign_key "web_hook_logs", "web_hooks", on_delete: :cascade
+  add_foreign_key "web_hooks", "projects", name: "fk_0c8ca6d9d1", on_delete: :cascade
 end

rubocop/cop/active_record_dependent.rb

+require_relative '../model_helpers'
+
+module RuboCop
+  module Cop
+    # Cop that prevents the use of `dependent: ...` in ActiveRecord models.
+    class ActiveRecordDependent < RuboCop::Cop::Cop
+      include ModelHelpers
+
+      MSG = 'Do not use `dependent: to remove associated data, ' \
+        'use foreign keys with cascading deletes instead'.freeze
+
+      METHOD_NAMES = [:has_many, :has_one, :belongs_to].freeze
+
+      def on_send(node)
+        return unless in_model?(node)
+        return unless METHOD_NAMES.include?(node.children[1])
+
+        node.children.last.each_node(:pair) do |pair|
+          key_name = pair.children[0].children[0]
+
+          add_offense(pair, :expression) if key_name == :dependent
+        end
+      end
+    end
+  end
+end

rubocop/cop/activerecord_serialize.rb → rubocop/cop/active_record_serialize.rb

@@ -3,7 +3,7 @@ require_relative '../model_helpers'
 module RuboCop
   module Cop
     # Cop that prevents the use of `serialize` in ActiveRecord models.
-    class ActiverecordSerialize < RuboCop::Cop::Cop
+    class ActiveRecordSerialize < RuboCop::Cop::Cop
       include ModelHelpers
 
       MSG = 'Do not store serialized data in the database, use separate columns and/or tables instead'.freeze

rubocop/rubocop.rb

 require_relative 'cop/custom_error_class'
 require_relative 'cop/gem_fetcher'
-require_relative 'cop/activerecord_serialize'
+require_relative 'cop/active_record_serialize'
 require_relative 'cop/redirect_with_status'
 require_relative 'cop/polymorphic_associations'
 require_relative 'cop/project_path_helper'
+require_relative 'cop/active_record_dependent'
 require_relative 'cop/migration/add_column'
 require_relative 'cop/migration/add_column_with_default_to_large_table'
 require_relative 'cop/migration/add_concurrent_foreign_key'

spec/factories/ci/runner_projects.rb

 FactoryGirl.define do
   factory :ci_runner_project, class: Ci::RunnerProject do
-    runner_id 1
-    project_id 1
+    runner factory: :ci_runner
+    project factory: :empty_project
   end
 end

spec/models/concerns/issuable_spec.rb

@@ -155,7 +155,7 @@ describe Issuable do
   end
 
   describe "#sort" do
-    let(:project) { build_stubbed(:empty_project) }
+    let(:project) { create(:empty_project) }
 
     context "by milestone due date" do
       # Correct order is:

spec/models/forked_project_link_spec.rb

@@ -42,7 +42,7 @@ describe ForkedProjectLink, "add link on fork" do
 
   describe '#forked?' do
     let(:project_to) { create(:project, forked_project_link: forked_project_link) }
-    let(:forked_project_link) { build(:forked_project_link) }
+    let(:forked_project_link) { create(:forked_project_link) }
 
     before do
       forked_project_link.forked_from_project = project_from
@@ -59,9 +59,9 @@ describe ForkedProjectLink, "add link on fork" do
     end
 
     it "project_to.destroy destroys fork_link" do
-      expect(forked_project_link).to receive(:destroy)
-
       project_to.destroy
+
+      expect(ForkedProjectLink.exists?(id: forked_project_link.id)).to eq(false)
     end
   end
 

spec/models/merge_request_spec.rb

@@ -10,7 +10,7 @@ describe MergeRequest, models: true do
     it { is_expected.to belong_to(:source_project).class_name('Project') }
     it { is_expected.to belong_to(:merge_user).class_name("User") }
     it { is_expected.to belong_to(:assignee) }
-    it { is_expected.to have_many(:merge_request_diffs).dependent(:destroy) }
+    it { is_expected.to have_many(:merge_request_diffs) }
   end
 
   describe 'modules' do

spec/models/project_spec.rb

@@ -7,50 +7,50 @@ describe Project, models: true do
     it { is_expected.to belong_to(:creator).class_name('User') }
     it { is_expected.to have_many(:users) }
     it { is_expected.to have_many(:services) }
-    it { is_expected.to have_many(:events).dependent(:destroy) }
-    it { is_expected.to have_many(:merge_requests).dependent(:destroy) }
-    it { is_expected.to have_many(:issues).dependent(:destroy) }
-    it { is_expected.to have_many(:milestones).dependent(:destroy) }
-    it { is_expected.to have_many(:project_members).dependent(:destroy) }
+    it { is_expected.to have_many(:events) }
+    it { is_expected.to have_many(:merge_requests) }
+    it { is_expected.to have_many(:issues) }
+    it { is_expected.to have_many(:milestones) }
+    it { is_expected.to have_many(:project_members).dependent(:delete_all) }
     it { is_expected.to have_many(:users).through(:project_members) }
-    it { is_expected.to have_many(:requesters).dependent(:destroy) }
-    it { is_expected.to have_many(:notes).dependent(:destroy) }
-    it { is_expected.to have_many(:snippets).class_name('ProjectSnippet').dependent(:destroy) }
-    it { is_expected.to have_many(:deploy_keys_projects).dependent(:destroy) }
+    it { is_expected.to have_many(:requesters).dependent(:delete_all) }
+    it { is_expected.to have_many(:notes) }
+    it { is_expected.to have_many(:snippets).class_name('ProjectSnippet') }
+    it { is_expected.to have_many(:deploy_keys_projects) }
     it { is_expected.to have_many(:deploy_keys) }
-    it { is_expected.to have_many(:hooks).dependent(:destroy) }
-    it { is_expected.to have_many(:protected_branches).dependent(:destroy) }
-    it { is_expected.to have_one(:forked_project_link).dependent(:destroy) }
-    it { is_expected.to have_one(:slack_service).dependent(:destroy) }
-    it { is_expected.to have_one(:microsoft_teams_service).dependent(:destroy) }
-    it { is_expected.to have_one(:mattermost_service).dependent(:destroy) }
-    it { is_expected.to have_one(:pushover_service).dependent(:destroy) }
-    it { is_expected.to have_one(:asana_service).dependent(:destroy) }
-    it { is_expected.to have_many(:boards).dependent(:destroy) }
-    it { is_expected.to have_one(:campfire_service).dependent(:destroy) }
-    it { is_expected.to have_one(:drone_ci_service).dependent(:destroy) }
-    it { is_expected.to have_one(:emails_on_push_service).dependent(:destroy) }
-    it { is_expected.to have_one(:pipelines_email_service).dependent(:destroy) }
-    it { is_expected.to have_one(:irker_service).dependent(:destroy) }
-    it { is_expected.to have_one(:pivotaltracker_service).dependent(:destroy) }
-    it { is_expected.to have_one(:hipchat_service).dependent(:destroy) }
-    it { is_expected.to have_one(:flowdock_service).dependent(:destroy) }
-    it { is_expected.to have_one(:assembla_service).dependent(:destroy) }
-    it { is_expected.to have_one(:slack_slash_commands_service).dependent(:destroy) }
-    it { is_expected.to have_one(:mattermost_slash_commands_service).dependent(:destroy) }
-    it { is_expected.to have_one(:gemnasium_service).dependent(:destroy) }
-    it { is_expected.to have_one(:buildkite_service).dependent(:destroy) }
-    it { is_expected.to have_one(:bamboo_service).dependent(:destroy) }
-    it { is_expected.to have_one(:teamcity_service).dependent(:destroy) }
-    it { is_expected.to have_one(:jira_service).dependent(:destroy) }
-    it { is_expected.to have_one(:redmine_service).dependent(:destroy) }
-    it { is_expected.to have_one(:custom_issue_tracker_service).dependent(:destroy) }
-    it { is_expected.to have_one(:bugzilla_service).dependent(:destroy) }
-    it { is_expected.to have_one(:gitlab_issue_tracker_service).dependent(:destroy) }
-    it { is_expected.to have_one(:external_wiki_service).dependent(:destroy) }
-    it { is_expected.to have_one(:project_feature).dependent(:destroy) }
-    it { is_expected.to have_one(:statistics).class_name('ProjectStatistics').dependent(:delete) }
-    it { is_expected.to have_one(:import_data).class_name('ProjectImportData').dependent(:delete) }
+    it { is_expected.to have_many(:hooks) }
+    it { is_expected.to have_many(:protected_branches) }
+    it { is_expected.to have_one(:forked_project_link) }
+    it { is_expected.to have_one(:slack_service) }
+    it { is_expected.to have_one(:microsoft_teams_service) }
+    it { is_expected.to have_one(:mattermost_service) }
+    it { is_expected.to have_one(:pushover_service) }
+    it { is_expected.to have_one(:asana_service) }
+    it { is_expected.to have_many(:boards) }
+    it { is_expected.to have_one(:campfire_service) }
+    it { is_expected.to have_one(:drone_ci_service) }
+    it { is_expected.to have_one(:emails_on_push_service) }
+    it { is_expected.to have_one(:pipelines_email_service) }
+    it { is_expected.to have_one(:irker_service) }
+    it { is_expected.to have_one(:pivotaltracker_service) }
+    it { is_expected.to have_one(:hipchat_service) }
+    it { is_expected.to have_one(:flowdock_service) }
+    it { is_expected.to have_one(:assembla_service) }
+    it { is_expected.to have_one(:slack_slash_commands_service) }
+    it { is_expected.to have_one(:mattermost_slash_commands_service) }
+    it { is_expected.to have_one(:gemnasium_service) }
+    it { is_expected.to have_one(:buildkite_service) }
+    it { is_expected.to have_one(:bamboo_service) }
+    it { is_expected.to have_one(:teamcity_service) }
+    it { is_expected.to have_one(:jira_service) }
+    it { is_expected.to have_one(:redmine_service) }
+    it { is_expected.to have_one(:custom_issue_tracker_service) }
+    it { is_expected.to have_one(:bugzilla_service) }
+    it { is_expected.to have_one(:gitlab_issue_tracker_service) }
+    it { is_expected.to have_one(:external_wiki_service) }
+    it { is_expected.to have_one(:project_feature) }
+    it { is_expected.to have_one(:statistics).class_name('ProjectStatistics') }
+    it { is_expected.to have_one(:import_data).class_name('ProjectImportData') }
     it { is_expected.to have_one(:last_event).class_name('Event') }
     it { is_expected.to have_one(:forked_from_project).through(:forked_project_link) }
     it { is_expected.to have_many(:commit_statuses) }
@@ -62,18 +62,18 @@ describe Project, models: true do
     it { is_expected.to have_many(:variables) }
     it { is_expected.to have_many(:triggers) }
     it { is_expected.to have_many(:pages_domains) }
-    it { is_expected.to have_many(:labels).class_name('ProjectLabel').dependent(:destroy) }
-    it { is_expected.to have_many(:users_star_projects).dependent(:destroy) }
-    it { is_expected.to have_many(:environments).dependent(:destroy) }
-    it { is_expected.to have_many(:deployments).dependent(:destroy) }
-    it { is_expected.to have_many(:todos).dependent(:destroy) }
-    it { is_expected.to have_many(:releases).dependent(:destroy) }
-    it { is_expected.to have_many(:lfs_objects_projects).dependent(:destroy) }
-    it { is_expected.to have_many(:project_group_links).dependent(:destroy) }
-    it { is_expected.to have_many(:notification_settings).dependent(:destroy) }
+    it { is_expected.to have_many(:labels).class_name('ProjectLabel') }
+    it { is_expected.to have_many(:users_star_projects) }
+    it { is_expected.to have_many(:environments) }
+    it { is_expected.to have_many(:deployments) }
+    it { is_expected.to have_many(:todos) }
+    it { is_expected.to have_many(:releases) }
+    it { is_expected.to have_many(:lfs_objects_projects) }
+    it { is_expected.to have_many(:project_group_links) }
+    it { is_expected.to have_many(:notification_settings).dependent(:delete_all) }
     it { is_expected.to have_many(:forks).through(:forked_project_links) }
     it { is_expected.to have_many(:uploads).dependent(:destroy) }
-    it { is_expected.to have_many(:pipeline_schedules).dependent(:destroy) }
+    it { is_expected.to have_many(:pipeline_schedules) }
 
     context 'after initialized' do
       it "has a project_feature" do
@@ -2199,4 +2199,21 @@ describe Project, models: true do
       end
     end
   end
+
+  describe '#remove_private_deploy_keys' do
+    it 'removes the private deploy keys of a project' do
+      project = create(:empty_project)
+
+      private_key = create(:deploy_key, public: false)
+      public_key = create(:deploy_key, public: true)
+
+      create(:deploy_keys_project, deploy_key: private_key, project: project)
+      create(:deploy_keys_project, deploy_key: public_key, project: project)
+
+      project.remove_private_deploy_keys
+
+      expect(project.deploy_keys.where(public: false).any?).to eq(false)
+      expect(project.deploy_keys.where(public: true).any?).to eq(true)
+    end
+  end
 end

spec/presenters/ci/build_presenter_spec.rb

@@ -85,7 +85,7 @@ describe Ci::BuildPresenter do
 
   describe 'quack like a Ci::Build permission-wise' do
     context 'user is not allowed' do
-      let(:project) { build_stubbed(:empty_project, public_builds: false) }
+      let(:project) { create(:empty_project, public_builds: false) }
 
       it 'returns false' do
         expect(presenter.can?(nil, :read_build)).to be_falsy
@@ -93,7 +93,7 @@ describe Ci::BuildPresenter do
     end
 
     context 'user is allowed' do
-      let(:project) { build_stubbed(:empty_project, :public) }
+      let(:project) { create(:empty_project, :public) }
 
       it 'returns true' do
         expect(presenter.can?(nil, :read_build)).to be_truthy

spec/rubocop/cop/active_record_dependent_spec.rb

+require 'spec_helper'
+require 'rubocop'
+require 'rubocop/rspec/support'
+require_relative '../../../rubocop/cop/active_record_dependent'
+
+describe RuboCop::Cop::ActiveRecordDependent do
+  include CopHelper
+
+  subject(:cop) { described_class.new }
+
+  context 'inside the app/models directory' do
+    it 'registers an offense when dependent: is used' do
+      allow(cop).to receive(:in_model?).and_return(true)
+
+      inspect_source(cop, 'belongs_to :foo, dependent: :destroy')
+
+      aggregate_failures do
+        expect(cop.offenses.size).to eq(1)
+        expect(cop.offenses.map(&:line)).to eq([1])
+      end
+    end
+  end
+
+  context 'outside the app/models directory' do
+    it 'does nothing' do
+      allow(cop).to receive(:in_model?).and_return(false)
+
+      inspect_source(cop, 'belongs_to :foo, dependent: :destroy')
+
+      expect(cop.offenses).to be_empty
+    end
+  end
+end

spec/rubocop/cop/activerecord_serialize_spec.rb → spec/rubocop/cop/active_record_serialize_spec.rb

 require 'spec_helper'
 require 'rubocop'
 require 'rubocop/rspec/support'
-require_relative '../../../rubocop/cop/activerecord_serialize'
+require_relative '../../../rubocop/cop/active_record_serialize'
 
-describe RuboCop::Cop::ActiverecordSerialize do
+describe RuboCop::Cop::ActiveRecordSerialize do
   include CopHelper
 
   subject(:cop) { described_class.new }

spec/workers/expire_build_instance_artifacts_worker_spec.rb

@@ -30,20 +30,6 @@ describe ExpireBuildInstanceArtifactsWorker do
           expect(build.reload.artifacts_file_identifier).to be_nil
         end
       end
-
-      context 'when associated project was removed' do
-        let(:build) do
-          create(:ci_build, :artifacts, artifacts_expiry) do |build|
-            build.project.pending_delete = true
-          end
-        end
-
-        it 'does not remove artifacts' do
-          expect do
-            build.reload.artifacts_file
-          end.not_to raise_error
-        end
-      end
     end
 
     context 'with not yet expired artifacts' do