Merge branch 'cache-action-compare-api' into 'master'

Add cache_action to repository compare [RUN ALL RSPEC] [RUN AS-IF-FOSS]

See merge request gitlab-org/gitlab!64407

config/feature_flags/development/api_caching_rate_limit_repository_compare.yml

+---
+name: api_caching_rate_limit_repository_compare
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/64407
+rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/334264
+milestone: '14.1'
+type: development
+group: group::source code
+default_enabled: false

lib/api/repositories.rb

@@ -120,24 +120,28 @@ module API
         optional :straight, type: Boolean, desc: 'Comparison method, `true` for direct comparison between `from` and `to` (`from`..`to`), `false` to compare using merge base (`from`...`to`)', default: false
       end
       get ':id/repository/compare' do
-        if params[:from_project_id].present?
-          target_project = MergeRequestTargetProjectFinder
-            .new(current_user: current_user, source_project: user_project, project_feature: :repository)
-            .execute(include_routes: true).find_by_id(params[:from_project_id])
-
-          if target_project.blank?
-            render_api_error!("Target project id:#{params[:from_project_id]} is not a fork of project id:#{params[:id]}", 400)
+        ff_enabled = Feature.enabled?(:api_caching_rate_limit_repository_compare, user_project, default_enabled: :yaml)
+
+        cache_action_if(ff_enabled, [user_project, :repository_compare, current_user, declared_params], expires_in: 30.seconds) do
+          if params[:from_project_id].present?
+            target_project = MergeRequestTargetProjectFinder
+              .new(current_user: current_user, source_project: user_project, project_feature: :repository)
+              .execute(include_routes: true).find_by_id(params[:from_project_id])
+
+            if target_project.blank?
+              render_api_error!("Target project id:#{params[:from_project_id]} is not a fork of project id:#{params[:id]}", 400)
+            end
+          else
+            target_project = user_project
           end
-        else
-          target_project = user_project
-        end
 
-        compare = CompareService.new(user_project, params[:to]).execute(target_project, params[:from], straight: params[:straight])
+          compare = CompareService.new(user_project, params[:to]).execute(target_project, params[:from], straight: params[:straight])
 
-        if compare
-          present compare, with: Entities::Compare
-        else
-          not_found!("Ref")
+          if compare
+            present compare, with: Entities::Compare
+          else
+            not_found!("Ref")
+          end
         end
       end
 

spec/requests/api/repositories_spec.rb

@@ -477,6 +477,17 @@ RSpec.describe API::Repositories do
         let(:request) { get api(route, guest) }
       end
     end
+
+    context 'api_caching_rate_limit_repository_compare is disabled' do
+      before do
+        stub_feature_flags(api_caching_rate_limit_repository_compare: false)
+      end
+
+      it_behaves_like 'repository compare' do
+        let(:project) { create(:project, :public, :repository) }
+        let(:current_user) { nil }
+      end
+    end
   end
 
   describe 'GET /projects/:id/repository/contributors' do