Preload user project access in group API

This fixes an N+1 in the /group/:id and /group/:id/projects endpoints.

Changelog: performance

lib/api/entities/group_detail.rb

@@ -16,7 +16,7 @@ module API
           options: { only_owned: true, limit: projects_limit }
         ).execute
 
-        Entities::Project.prepare_relation(projects)
+        Entities::Project.prepare_relation(projects, options)
       end
 
       expose :shared_projects, using: Entities::Project do |group, options|
@@ -26,7 +26,7 @@ module API
           options: { only_shared: true, limit: projects_limit }
         ).execute
 
-        Entities::Project.prepare_relation(projects)
+        Entities::Project.prepare_relation(projects, options)
       end
 
       def projects_limit

lib/api/groups.rb

@@ -92,7 +92,7 @@ module API
 
         projects, options = with_custom_attributes(projects, options)
 
-        present options[:with].prepare_relation(projects), options
+        present options[:with].prepare_relation(projects, options), options
       end
 
       def present_groups(params, groups)

lib/api/projects.rb

@@ -182,8 +182,6 @@ module API
           [options[:with].prepare_relation(projects, options), options]
         end
 
-        Preloaders::UserMaxAccessLevelInProjectsPreloader.new(records, current_user).execute if current_user
-
         present records, options
       end
 

lib/api/projects_relation_builder.rb

@@ -12,6 +12,8 @@ module API
 
         preload_repository_cache(projects_relation)
 
+        Preloaders::UserMaxAccessLevelInProjectsPreloader.new(projects_relation, options[:current_user]).execute if options[:current_user]
+
         projects_relation
       end
 

spec/requests/api/groups_spec.rb

@@ -728,16 +728,16 @@ RSpec.describe API::Groups do
       end
 
       it 'avoids N+1 queries with project links' do
-        get api("/groups/#{group1.id}", admin)
+        get api("/groups/#{group1.id}", user1)
 
         control_count = ActiveRecord::QueryRecorder.new do
-          get api("/groups/#{group1.id}", admin)
+          get api("/groups/#{group1.id}", user1)
         end.count
 
         create(:project, namespace: group1)
 
         expect do
-          get api("/groups/#{group1.id}", admin)
+          get api("/groups/#{group1.id}", user1)
         end.not_to exceed_query_limit(control_count)
       end
 
@@ -746,7 +746,7 @@ RSpec.describe API::Groups do
         create(:group_group_link, shared_group: group1, shared_with_group: create(:group))
 
         control_count = ActiveRecord::QueryRecorder.new do
-          get api("/groups/#{group1.id}", admin)
+          get api("/groups/#{group1.id}", user1)
         end.count
 
         # setup "n" more shared groups
@@ -755,7 +755,7 @@ RSpec.describe API::Groups do
 
         # test that no of queries for 1 shared group is same as for n shared groups
         expect do
-          get api("/groups/#{group1.id}", admin)
+          get api("/groups/#{group1.id}", user1)
         end.not_to exceed_query_limit(control_count)
       end
     end
@@ -1179,6 +1179,20 @@ RSpec.describe API::Groups do
         expect(json_response.length).to eq(1)
         expect(json_response.first['name']).to eq(project1.name)
       end
+
+      it 'avoids N+1 queries' do
+        get api("/groups/#{group1.id}/projects", user1)
+
+        control_count = ActiveRecord::QueryRecorder.new do
+          get api("/groups/#{group1.id}/projects", user1)
+        end.count
+
+        create(:project, namespace: group1)
+
+        expect do
+          get api("/groups/#{group1.id}/projects", user1)
+        end.not_to exceed_query_limit(control_count)
+      end
     end
 
     context "when authenticated as admin" do
@@ -1196,20 +1210,6 @@ RSpec.describe API::Groups do
 
         expect(response).to have_gitlab_http_status(:not_found)
       end
-
-      it 'avoids N+1 queries' do
-        get api("/groups/#{group1.id}/projects", admin)
-
-        control_count = ActiveRecord::QueryRecorder.new do
-          get api("/groups/#{group1.id}/projects", admin)
-        end.count
-
-        create(:project, namespace: group1)
-
-        expect do
-          get api("/groups/#{group1.id}/projects", admin)
-        end.not_to exceed_query_limit(control_count)
-      end
     end
 
     context 'when using group path in URL' do