Added EE foreign keys pointing to "projects"

This adds various missing foreign keys (with cascading deletes) that
either point directly or indirectly to the "projects" table.

app/models/merge_request.rb

@@ -15,9 +15,9 @@ class MergeRequest < ActiveRecord::Base
   belongs_to :source_project, class_name: "Project"
   belongs_to :merge_user, class_name: "User"
 
-  has_many :approvals, dependent: :destroy
-  has_many :approvers, as: :target, dependent: :destroy
-  has_many :approver_groups, as: :target, dependent: :destroy
+  has_many :approvals
+  has_many :approvers, as: :target, dependent: :delete_all # rubocop:disable Cop/ActiveRecordDependent
+  has_many :approver_groups, as: :target, dependent: :delete_all # rubocop:disable Cop/ActiveRecordDependent
   has_many :merge_request_diffs
   has_one :merge_request_diff,
     -> { order('merge_request_diffs.id DESC') }

db/migrate/20170622124246_add_ee_foreign_keys_pointing_to_projects.rb

+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class AddEEForeignKeysPointingToProjects < ActiveRecord::Migration
+  include Gitlab::Database::MigrationHelpers
+
+  disable_ddl_transaction!
+
+  # Set this constant to true if this migration requires downtime.
+  DOWNTIME = false
+
+  TABLES = [
+    :push_rules,
+    :index_statuses,
+    :remote_mirrors,
+    :path_locks
+  ]
+
+  def up
+    # These foreign keys lack an ON DELETE clause.
+    remove_foreign_key_without_error(:path_locks, column: :project_id)
+    remove_foreign_key_without_error(:remote_mirrors, column: :project_id)
+
+    TABLES.each do |table|
+      quoted_table = connection.quote_table_name(table)
+
+      execute <<-EOF
+      DELETE FROM #{quoted_table}
+      WHERE NOT EXISTS (
+        SELECT true
+        FROM projects
+        WHERE projects.id = #{quoted_table}.project_id
+      )
+      AND project_id IS NOT NULL
+      EOF
+
+      add_concurrent_foreign_key(table, :projects, column: :project_id)
+    end
+  end
+
+  def down
+    # We'll leave the path_locks / remote_mirrors foreign keys in place since
+    # there's no particular reason to remove the ON DELETE clause here.
+    [:push_rules, :index_statuses].each do |table|
+      remove_foreign_key_without_error(table, column: :project_id)
+    end
+  end
+
+  def remove_foreign_key_without_error(*args)
+    remove_foreign_key(*args)
+  rescue ArgumentError
+  end
+end

db/migrate/20170622131529_add_foreign_key_for_approvals.rb

+# See http://doc.gitlab.com/ce/development/migration_style_guide.html
+# for more information on how to write migrations for GitLab.
+
+class AddForeignKeyForApprovals < 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 approvals
+    WHERE NOT EXISTS (
+      SELECT true
+      FROM merge_requests
+      WHERE merge_requests.id = approvals.merge_request_id
+    )
+    EOF
+
+    add_concurrent_foreign_key(:approvals,
+                               :merge_requests,
+                               column: :merge_request_id)
+  end
+
+  def down
+    remove_foreign_key(:approvals, column: :merge_request_id)
+  end
+end

db/schema.rb

@@ -1814,6 +1814,7 @@ ActiveRecord::Schema.define(version: 20170627211700) 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 "approvals", "merge_requests", name: "fk_310d714958", on_delete: :cascade
   add_foreign_key "approver_groups", "namespaces", column: "group_id", on_delete: :cascade
   add_foreign_key "boards", "projects", name: "fk_f15266b5f9", on_delete: :cascade
   add_foreign_key "chat_teams", "namespaces", on_delete: :cascade
@@ -1846,6 +1847,7 @@ ActiveRecord::Schema.define(version: 20170627211700) do
   add_foreign_key "geo_event_log", "geo_repository_deleted_events", column: "repository_deleted_event_id", name: "fk_c4b1c1f66e", on_delete: :cascade
   add_foreign_key "geo_event_log", "geo_repository_updated_events", column: "repository_updated_event_id", on_delete: :cascade
   add_foreign_key "geo_repository_updated_events", "projects", on_delete: :cascade
+  add_foreign_key "index_statuses", "projects", name: "fk_74b2492545", 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_links", "issues", column: "source_id", name: "fk_c900194ff2", on_delete: :cascade
@@ -1870,7 +1872,7 @@ ActiveRecord::Schema.define(version: 20170627211700) do
   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 "path_locks", "projects"
+  add_foreign_key "path_locks", "projects", name: "fk_5265c98f24", on_delete: :cascade
   add_foreign_key "path_locks", "users"
   add_foreign_key "personal_access_tokens", "users"
   add_foreign_key "project_authorizations", "projects", on_delete: :cascade
@@ -1891,8 +1893,9 @@ ActiveRecord::Schema.define(version: 20170627211700) do
   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 "push_rules", "projects", name: "fk_83b29894de", on_delete: :cascade
   add_foreign_key "releases", "projects", name: "fk_47fe2a0596", on_delete: :cascade
-  add_foreign_key "remote_mirrors", "projects"
+  add_foreign_key "remote_mirrors", "projects", name: "fk_43a9aa4ca8", 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

spec/services/merge_requests/approval_service_spec.rb

@@ -3,7 +3,7 @@ require 'rails_helper'
 describe MergeRequests::ApprovalService, services: true do
   describe '#execute' do
     let(:user)          { create(:user) }
-    let(:merge_request) { build_stubbed(:merge_request) }
+    let(:merge_request) { create(:merge_request) }
     let(:project)       { merge_request.project }
     let!(:todo)         { create(:todo, user: user, project: project, target: merge_request) }