Merge branch 'dblessing_group_projects_api_perf' into 'master'

Group API Plans Performance

See merge request gitlab-org/gitlab!77538

app/models/preloaders/single_hierarchy_project_group_plans_preloader.rb

+# frozen_string_literal: true
+
+module Preloaders
+  class SingleHierarchyProjectGroupPlansPreloader
+    attr_reader :projects
+
+    def initialize(projects_relation)
+      @projects = projects_relation
+    end
+
+    def execute
+      # no-op in FOSS
+    end
+  end
+end
+
+Preloaders::SingleHierarchyProjectGroupPlansPreloader.prepend_mod_with('Preloaders::SingleHierarchyProjectGroupPlansPreloader')

config/feature_flags/development/group_project_api_preload_plans.yml

+---
+name: group_project_api_preload_plans
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/77538
+rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/350176
+milestone: '14.7'
+type: development
+group: group::authentication and authorization
+default_enabled: false

ee/app/models/ee/preloaders/single_hierarchy_project_group_plans_preloader.rb

+# frozen_string_literal: true
+
+module EE
+  module Preloaders
+    module SingleHierarchyProjectGroupPlansPreloader
+      def execute
+        return unless ::Feature.enabled?(:group_project_api_preload_plans, default_enabled: :yaml)
+        return unless ::Gitlab::CurrentSettings.should_check_namespace_plan?
+        return unless project = projects.take
+
+        plans = project.namespace.root_ancestor.plans
+
+        preload_plans(plans)
+      end
+
+      def preload_plans(plans)
+        return unless plans.any?
+
+        projects.each do |project|
+          project.namespace.memoized_plans = plans
+        end
+      end
+    end
+  end
+end

ee/spec/requests/api/groups_spec.rb

@@ -632,6 +632,54 @@ RSpec.describe API::Groups do
         end
       end
     end
+
+    context 'when namespace license checks are enabled', :saas do
+      before do
+        enable_namespace_license_check!
+      end
+
+      context 'when there are plans and projects' do
+        let(:group) { create(:group_with_plan, plan: :ultimate_plan) }
+
+        before do
+          subgroup = create(:group, parent: group)
+          create(:project, group: group)
+          create(:project, group: subgroup)
+        end
+
+        it 'only loads plans once' do
+          expect(Plan).to receive(:hosted_plans_for_namespaces).once.and_call_original
+
+          get api("/groups/#{group.id}/projects", user), params: { include_subgroups: true }
+
+          expect(response).to have_gitlab_http_status(:ok)
+        end
+
+        context 'when the feature flag is disabled' do
+          before do
+            stub_feature_flags(group_project_api_preload_plans: false)
+          end
+
+          it 'does not preload plans' do
+            expect(Plan).to receive(:hosted_plans_for_namespaces).at_least(:twice).and_call_original
+
+            get api("/groups/#{group.id}/projects", user), params: { include_subgroups: true }
+
+            expect(response).to have_gitlab_http_status(:ok)
+          end
+        end
+      end
+
+      context 'when there are no projects' do
+        let(:group) { create(:group) }
+
+        it 'completes the request without error' do
+          get api("/groups/#{group.id}/projects", user), params: { include_subgroups: true }
+
+          expect(response).to have_gitlab_http_status(:ok)
+        end
+      end
+    end
   end
 
   describe 'GET group/:id/audit_events' do

lib/api/groups.rb

@@ -84,10 +84,11 @@ module API
         paginate(projects)
       end
 
-      def present_projects(params, projects)
+      def present_projects(params, projects, single_hierarchy: false)
         options = {
           with: params[:simple] ? Entities::BasicProjectDetails : Entities::Project,
-          current_user: current_user
+          current_user: current_user,
+          single_hierarchy: single_hierarchy
         }
 
         projects, options = with_custom_attributes(projects, options)
@@ -306,7 +307,7 @@ module API
 
         projects = find_group_projects(params, finder_options)
 
-        present_projects(params, projects)
+        present_projects(params, projects, single_hierarchy: true)
       end
 
       desc 'Get a list of shared projects in this group' do

lib/api/projects_relation_builder.rb

@@ -13,6 +13,7 @@ module API
         preload_repository_cache(projects_relation)
 
         Preloaders::UserMaxAccessLevelInProjectsPreloader.new(projects_relation, options[:current_user]).execute if options[:current_user]
+        Preloaders::SingleHierarchyProjectGroupPlansPreloader.new(projects_relation).execute if options[:single_hierarchy]
 
         projects_relation
       end