Merge branch '324745-preload-projects-for-elasticsearch-indexing' into 'master'

Remove N+1 DB queries from indexing projects in Elasticsearch

See merge request gitlab-org/gitlab!57794

ee/changelogs/unreleased/324745-preload-projects-for-elasticsearch-indexing.yml

+---
+title: Remove N+1 DB queries from indexing projects in Elasticsearch
+merge_request: 57794
+author:
+type: performance

ee/lib/elastic/latest/project_class_proxy.rb

@@ -49,6 +49,12 @@ module Elastic
 
         search(query_hash, options)
       end
+
+      # rubocop: disable CodeReuse/ActiveRecord
+      def preload_indexing_data(relation)
+        relation.includes(:project_feature, :route)
+      end
+      # rubocop: enable CodeReuse/ActiveRecord
     end
   end
 end

ee/spec/services/elastic/process_bookkeeping_service_spec.rb

@@ -209,6 +209,20 @@ RSpec.describe Elastic::ProcessBookkeepingService, :clean_gitlab_redis_shared_st
     end
 
     context 'N+1 queries' do
+      it 'does not have N+1 queries for projects' do
+        projects = create_list(:project, 2)
+
+        described_class.track!(*projects)
+
+        control = ActiveRecord::QueryRecorder.new(skip_cached: false) { described_class.new.execute }
+
+        projects += create_list(:project, 3)
+
+        described_class.track!(*projects)
+
+        expect { described_class.new.execute }.not_to exceed_all_query_limit(control)
+      end
+
       it 'does not have N+1 queries for notes' do
         notes = []