Merge branch 'fj-fix-n-plus-one-in-dashboard-snippets' into 'master'

Fix N+1 in Dashboard::SnippetsController#index

See merge request gitlab-org/gitlab!50569

app/controllers/dashboard/snippets_controller.rb

@@ -18,6 +18,7 @@ class Dashboard::SnippetsController < Dashboard::ApplicationController
       .execute
       .page(params[:page])
       .inc_author
+      .inc_projects_namespace_route
 
     return if redirect_out_of_range(@snippets)
 

app/models/snippet.rb

@@ -83,6 +83,7 @@ class Snippet < ApplicationRecord
   scope :inc_author, -> { includes(:author) }
   scope :inc_relations_for_view, -> { includes(author: :status) }
   scope :with_statistics, -> { joins(:statistics) }
+  scope :inc_projects_namespace_route, -> { includes(project: [:route, :namespace]) }
 
   attr_mentionable :description
 

changelogs/unreleased/fj-fix-n-plus-one-in-dashboard-snippets.yml

+---
+title: Fix N+1 when rendering snippets in the dashboard
+merge_request: 50569
+author:
+type: performance

spec/controllers/dashboard/snippets_controller_spec.rb

@@ -28,5 +28,24 @@ RSpec.describe Dashboard::SnippetsController do
     end
 
     it_behaves_like 'snippets sort order'
+
+    context 'when views are rendered' do
+      render_views
+
+      it 'avoids N+1 database queries' do
+        # Warming call to load everything non snippet related
+        get(:index)
+
+        project = create(:project, namespace: user.namespace)
+        create(:project_snippet, project: project, author: user)
+
+        control_count = ActiveRecord::QueryRecorder.new { get(:index) }.count
+
+        project = create(:project, namespace: user.namespace)
+        create(:project_snippet, project: project, author: user)
+
+        expect { get(:index) }.not_to exceed_query_limit(control_count)
+      end
+    end
   end
 end