Fix timeouts on test webhooks

The Issues, Merge Requests and Notes test webhooks were susceptible to
timeouts due to the oldest records being selected to be in the test
webhook payload.

Indexes on these tables seem to favour sorting newest to oldest, the
difference between selecting the oldest Issue, Merge Request, or Note vs
the newest for `gitlab-org/gitlab` is ~ 25 seconds (or sometimes more)
on `#database-lab` (which is slower than production, but indicative) vs
~10 milliseconds when selecting the newest records.

Finders are now used for all scoping to make the scoping even safer.

https://gitlab.com/gitlab-org/gitlab/-/issues/290116

app/services/concerns/integrations/project_test_data.rb

@@ -8,22 +8,41 @@ module Integrations
       Gitlab::DataBuilder::Push.build_sample(project, current_user)
     end
 
+    def use_optimal_query?
+      Feature.enabled?(:integrations_test_webhook_optimizations, project)
+    end
+
     def note_events_data
-      note = project.notes.first
+      note = if use_optimal_query?
+               NotesFinder.new(current_user, project: project, target: project).execute.reorder(nil).last # rubocop: disable CodeReuse/ActiveRecord
+             else
+               project.notes.first
+             end
+
       return { error: s_('TestHooks|Ensure the project has notes.') } unless note.present?
 
       Gitlab::DataBuilder::Note.build(note, current_user)
     end
 
     def issues_events_data
-      issue = project.issues.first
+      issue = if use_optimal_query?
+                IssuesFinder.new(current_user, project_id: project.id, sort: 'created_desc').execute.first
+              else
+                project.issues.first
+              end
+
       return { error: s_('TestHooks|Ensure the project has issues.') } unless issue.present?
 
       issue.to_hook_data(current_user)
     end
 
     def merge_requests_events_data
-      merge_request = project.merge_requests.first
+      merge_request = if use_optimal_query?
+                        MergeRequestsFinder.new(current_user, project_id: project.id, sort: 'created_desc').execute.first
+                      else
+                        project.merge_requests.first
+                      end
+
       return { error: s_('TestHooks|Ensure the project has merge requests.') } unless merge_request.present?
 
       merge_request.to_hook_data(current_user)

config/feature_flags/development/integrations_test_webhook_optimizations.yml

+---
+name: integrations_test_webhook_optimizations
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/52646
+rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/300105
+milestone: '13.9'
+type: development
+group: group::ecosystem
+default_enabled: false

spec/services/integrations/test/project_service_spec.rb

@@ -3,11 +3,10 @@
 require 'spec_helper'
 
 RSpec.describe Integrations::Test::ProjectService do
-  let(:user) { double('user') }
-
   describe '#execute' do
-    let(:project) { create(:project) }
+    let_it_be(:project) { create(:project) }
     let(:integration) { create(:slack_service, project: project) }
+    let(:user) { project.owner }
     let(:event) { nil }
     let(:sample_data) { { data: 'sample' } }
     let(:success_result) { { success: true, result: {} } }
@@ -70,16 +69,34 @@ RSpec.describe Integrations::Test::ProjectService do
         end
 
         it 'executes integration' do
-          allow(project).to receive(:notes).and_return([Note.new])
+          create(:note, project: project)
+
           allow(Gitlab::DataBuilder::Note).to receive(:build).and_return(sample_data)
+          allow_next_instance_of(NotesFinder) do |finder|
+            allow(finder).to receive(:execute).and_return(Note.all)
+          end
 
           expect(integration).to receive(:test).with(sample_data).and_return(success_result)
           expect(subject).to eq(success_result)
         end
+
+        context 'when the query optimization feature flag is disabled' do
+          before do
+            stub_feature_flags(integrations_test_webhook_optimizations: false)
           end
 
-      context 'issue' do
-        let(:event) { 'issue' }
+          it 'executes the old query' do
+            allow(Gitlab::DataBuilder::Note).to receive(:build).and_return(sample_data)
+
+            expect(NotesFinder).not_to receive(:new)
+            expect(project).to receive(:notes).and_return([Note.new])
+            expect(integration).to receive(:test).with(sample_data).and_return(success_result)
+            expect(subject).to eq(success_result)
+          end
+        end
+      end
+
+      shared_examples_for 'a test of an integration that operates on issues' do
         let(:issue) { build(:issue) }
 
         it 'returns error message if not enough data' do
@@ -90,32 +107,45 @@ RSpec.describe Integrations::Test::ProjectService do
         it 'executes integration' do
           allow(project).to receive(:issues).and_return([issue])
           allow(issue).to receive(:to_hook_data).and_return(sample_data)
+          allow_next_instance_of(IssuesFinder) do |finder|
+            allow(finder).to receive(:execute).and_return([issue])
+          end
 
           expect(integration).to receive(:test).with(sample_data).and_return(success_result)
           expect(subject).to eq(success_result)
         end
-      end
 
-      context 'confidential_issue' do
-        let(:event) { 'confidential_issue' }
-        let(:issue) { build(:issue) }
-
-        it 'returns error message if not enough data' do
-          expect(integration).not_to receive(:test)
-          expect(subject).to include({ status: :error, message: 'Ensure the project has issues.' })
+        context 'when the query optimization feature flag is disabled' do
+          before do
+            stub_feature_flags(integrations_test_webhook_optimizations: false)
           end
 
-        it 'executes integration' do
-          allow(project).to receive(:issues).and_return([issue])
+          it 'executes the old query' do
             allow(issue).to receive(:to_hook_data).and_return(sample_data)
 
+            expect(IssuesFinder).not_to receive(:new)
+            expect(project).to receive(:issues).and_return([issue])
             expect(integration).to receive(:test).with(sample_data).and_return(success_result)
             expect(subject).to eq(success_result)
           end
         end
+      end
+
+      context 'issue' do
+        let(:event) { 'issue' }
+
+        it_behaves_like 'a test of an integration that operates on issues'
+      end
+
+      context 'confidential_issue' do
+        let(:event) { 'confidential_issue' }
+
+        it_behaves_like 'a test of an integration that operates on issues'
+      end
 
       context 'merge_request' do
         let(:event) { 'merge_request' }
+        let(:merge_request) { build(:merge_request) }
 
         it 'returns error message if not enough data' do
           expect(integration).not_to receive(:test)
@@ -123,16 +153,34 @@ RSpec.describe Integrations::Test::ProjectService do
         end
 
         it 'executes integration' do
-          create(:merge_request, source_project: project)
-          allow_any_instance_of(MergeRequest).to receive(:to_hook_data).and_return(sample_data)
+          allow(merge_request).to receive(:to_hook_data).and_return(sample_data)
+          allow_next_instance_of(MergeRequestsFinder) do |finder|
+            allow(finder).to receive(:execute).and_return([merge_request])
+          end
+
+          expect(integration).to receive(:test).with(sample_data).and_return(success_result)
+          expect(subject).to include(success_result)
+        end
+
+        context 'when the query optimization feature flag is disabled' do
+          before do
+            stub_feature_flags(integrations_test_webhook_optimizations: false)
+          end
+
+          it 'executes the old query' do
+            expect(MergeRequestsFinder).not_to receive(:new)
+            expect(project).to receive(:merge_requests).and_return([merge_request])
+
+            allow(merge_request).to receive(:to_hook_data).and_return(sample_data)
 
             expect(integration).to receive(:test).with(sample_data).and_return(success_result)
             expect(subject).to eq(success_result)
           end
         end
+      end
 
       context 'deployment' do
-        let(:project) { create(:project, :test_repo) }
+        let_it_be(:project) { create(:project, :test_repo) }
         let(:event) { 'deployment' }
 
         it 'returns error message if not enough data' do
@@ -167,7 +215,7 @@ RSpec.describe Integrations::Test::ProjectService do
       end
 
       context 'wiki_page' do
-        let(:project) { create(:project, :wiki_repo) }
+        let_it_be(:project) { create(:project, :wiki_repo) }
         let(:event) { 'wiki_page' }
 
         it 'returns error message if wiki disabled' do

spec/services/test_hooks/project_service_spec.rb

@@ -6,7 +6,7 @@ RSpec.describe TestHooks::ProjectService do
   let(:current_user) { create(:user) }
 
   describe '#execute' do
-    let(:project) { create(:project, :repository) }
+    let_it_be(:project) { create(:project, :repository) }
     let(:hook) { create(:project_hook, project: project) }
     let(:trigger) { 'not_implemented_events' }
     let(:service) { described_class.new(hook, current_user, trigger) }
@@ -61,17 +61,34 @@ RSpec.describe TestHooks::ProjectService do
       end
 
       it 'executes hook' do
-        allow(project).to receive(:notes).and_return([Note.new])
+        create(:note, project: project)
+
         allow(Gitlab::DataBuilder::Note).to receive(:build).and_return(sample_data)
+        allow_next_instance_of(NotesFinder) do |finder|
+          allow(finder).to receive(:execute).and_return(Note.all)
+        end
 
         expect(hook).to receive(:execute).with(sample_data, trigger_key).and_return(success_result)
         expect(service.execute).to include(success_result)
       end
+
+      context 'when the query optimization feature flag is disabled' do
+        before do
+          stub_feature_flags(integrations_test_webhook_optimizations: false)
         end
 
-    context 'issues_events' do
-      let(:trigger) { 'issues_events' }
-      let(:trigger_key) { :issue_hooks }
+        it 'executes the old query' do
+          allow(Gitlab::DataBuilder::Note).to receive(:build).and_return(sample_data)
+
+          expect(NotesFinder).not_to receive(:new)
+          expect(project).to receive(:notes).and_return([Note.new])
+          expect(hook).to receive(:execute).with(sample_data, trigger_key).and_return(success_result)
+          expect(service.execute).to include(success_result)
+        end
+      end
+    end
+
+    shared_examples_for 'a test webhook that operates on issues' do
       let(:issue) { build(:issue) }
 
       it 'returns error message if not enough data' do
@@ -80,36 +97,49 @@ RSpec.describe TestHooks::ProjectService do
       end
 
       it 'executes hook' do
-        allow(project).to receive(:issues).and_return([issue])
         allow(issue).to receive(:to_hook_data).and_return(sample_data)
+        allow_next_instance_of(IssuesFinder) do |finder|
+          allow(finder).to receive(:execute).and_return([issue])
+        end
 
         expect(hook).to receive(:execute).with(sample_data, trigger_key).and_return(success_result)
         expect(service.execute).to include(success_result)
       end
-    end
-
-    context 'confidential_issues_events' do
-      let(:trigger) { 'confidential_issues_events' }
-      let(:trigger_key) { :confidential_issue_hooks }
-      let(:issue) { build(:issue) }
 
-      it 'returns error message if not enough data' do
-        expect(hook).not_to receive(:execute)
-        expect(service.execute).to include({ status: :error, message: 'Ensure the project has issues.' })
+      context 'when the query optimization feature flag is disabled' do
+        before do
+          stub_feature_flags(integrations_test_webhook_optimizations: false)
         end
 
-      it 'executes hook' do
-        allow(project).to receive(:issues).and_return([issue])
+        it 'executes the old query' do
           allow(issue).to receive(:to_hook_data).and_return(sample_data)
 
+          expect(IssuesFinder).not_to receive(:new)
+          expect(project).to receive(:issues).and_return([issue])
           expect(hook).to receive(:execute).with(sample_data, trigger_key).and_return(success_result)
           expect(service.execute).to include(success_result)
         end
       end
+    end
+
+    context 'issues_events' do
+      let(:trigger) { 'issues_events' }
+      let(:trigger_key) { :issue_hooks }
+
+      it_behaves_like 'a test webhook that operates on issues'
+    end
+
+    context 'confidential_issues_events' do
+      let(:trigger) { 'confidential_issues_events' }
+      let(:trigger_key) { :confidential_issue_hooks }
+
+      it_behaves_like 'a test webhook that operates on issues'
+    end
 
     context 'merge_requests_events' do
       let(:trigger) { 'merge_requests_events' }
       let(:trigger_key) { :merge_request_hooks }
+      let(:merge_request) { build(:merge_request) }
 
       it 'returns error message if not enough data' do
         expect(hook).not_to receive(:execute)
@@ -117,12 +147,29 @@ RSpec.describe TestHooks::ProjectService do
       end
 
       it 'executes hook' do
-        create(:merge_request, source_project: project)
-        allow_any_instance_of(MergeRequest).to receive(:to_hook_data).and_return(sample_data)
+        allow(merge_request).to receive(:to_hook_data).and_return(sample_data)
+        allow_next_instance_of(MergeRequestsFinder) do |finder|
+          allow(finder).to receive(:execute).and_return([merge_request])
+        end
 
         expect(hook).to receive(:execute).with(sample_data, trigger_key).and_return(success_result)
         expect(service.execute).to include(success_result)
       end
+
+      context 'when the query optimization feature flag is disabled' do
+        before do
+          stub_feature_flags(integrations_test_webhook_optimizations: false)
+        end
+
+        it 'executes the old query' do
+          allow(merge_request).to receive(:to_hook_data).and_return(sample_data)
+
+          expect(MergeRequestsFinder).not_to receive(:new)
+          expect(project).to receive(:merge_requests).and_return([merge_request])
+          expect(hook).to receive(:execute).with(sample_data, trigger_key).and_return(success_result)
+          expect(service.execute).to include(success_result)
+        end
+      end
     end
 
     context 'job_events' do
@@ -162,7 +209,7 @@ RSpec.describe TestHooks::ProjectService do
     end
 
     context 'wiki_page_events' do
-      let(:project) { create(:project, :wiki_repo) }
+      let_it_be(:project) { create(:project, :wiki_repo) }
       let(:trigger) { 'wiki_page_events' }
       let(:trigger_key) { :wiki_page_hooks }