Add an event handler for design repository update events

ee/lib/gitlab/geo/log_cursor/events/design_repository_updated_event.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module Geo
+    module LogCursor
+      module Events
+        class DesignRepositoryUpdatedEvent
+          include BaseEvent
+
+          def process
+            job_id =
+              unless skippable?
+                registry.repository_updated!
+                schedule_job(event)
+              end
+
+            log_event(job_id)
+          end
+
+          private
+
+          def registry
+            @registry ||= ::Geo::DesignRegistry.safe_find_or_create_by(project_id: event.project_id)
+          end
+
+          def schedule_job(event)
+            enqueue_job_if_shard_healthy(event) do
+              ::Geo::DesignRepositorySyncWorker.perform_async(event.project_id)
+            end
+          end
+
+          def skippable?
+            Feature.disabled?(:enable_geo_design_sync)
+          end
+
+          def log_event(job_id)
+            logger.event_info(
+              created_at,
+              'Design repository update',
+              project_id: event.project_id,
+              scheduled_at: Time.now,
+              skippable: skippable?,
+              job_id: job_id)
+          end
+        end
+      end
+    end
+  end
+end

ee/spec/factories/geo/event_log.rb

@@ -49,6 +49,10 @@ FactoryBot.define do
     trait :container_repository_updated_event do
       container_repository_updated_event factory: :geo_container_repository_updated_event
     end
+
+    trait :design_repository_updated_event do
+      repository_updated_event factory: :geo_design_repository_updated_event
+    end
   end
 
   factory :geo_repository_created_event, class: Geo::RepositoryCreatedEvent do
@@ -63,7 +67,15 @@ FactoryBot.define do
   factory :geo_repository_updated_event, class: Geo::RepositoryUpdatedEvent do
     project
 
-    source { 0 }
+    source { Geo::RepositoryUpdatedEvent::REPOSITORY }
+    branches_affected { 0 }
+    tags_affected { 0 }
+  end
+
+  factory :geo_design_repository_updated_event, class: Geo::RepositoryUpdatedEvent do
+    project
+
+    source { Geo::RepositoryUpdatedEvent::DESIGN }
     branches_affected { 0 }
     tags_affected { 0 }
   end

ee/spec/lib/gitlab/geo/log_cursor/events/design_repository_updated_event_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::Geo::LogCursor::Events::DesignRepositoryUpdatedEvent, :clean_gitlab_redis_shared_state do
+  include ::EE::GeoHelpers
+
+  let_it_be(:secondary) { create(:geo_node) }
+
+  let(:logger) { Gitlab::Geo::LogCursor::Logger.new(described_class, Logger::INFO) }
+  let(:project) { create(:project) }
+  let(:event) { create(:geo_design_repository_updated_event, project: project) }
+  let(:event_log) { create(:geo_event_log, repository_updated_event: event) }
+  let!(:event_log_state) { create(:geo_event_log_state, event_id: event_log.id - 1) }
+
+  subject { described_class.new(event, Time.now, logger) }
+
+  around do |example|
+    Sidekiq::Testing.fake! { example.run }
+  end
+
+  before do
+    stub_current_geo_node(secondary)
+  end
+
+  shared_examples 'DesignRepositoryUpdatedEvent' do
+    it 'creates a new registry when a design registry does not exist' do
+      expect { subject.process }.to change(Geo::DesignRegistry, :count).by(1)
+    end
+
+    it 'marks registry as pending when a design registry exists' do
+      registry = create(:geo_design_registry, :synced, project: project)
+
+      expect { subject.process }.to change { registry.reload.state }.from('synced').to('pending')
+    end
+  end
+
+  describe '#process' do
+    context 'when the feature flag is disabled' do
+      before do
+        stub_feature_flags(enable_geo_design_sync: false)
+      end
+
+      it 'does not create a design registry' do
+        expect { subject.process }.not_to change(Geo::DesignRegistry, :count)
+      end
+
+      it 'does not schedule a Geo::DesignRepositorySyncWorker job' do
+        expect(Geo::DesignRepositorySyncWorker).not_to receive(:perform_async).with(project.id)
+
+        subject.process
+      end
+    end
+
+    context 'when the feature flag is disabled' do
+      before do
+        stub_feature_flags(enable_geo_design_sync: true)
+      end
+
+      context 'when the associated shard is healthy' do
+        before do
+          allow(Gitlab::ShardHealthCache).to receive(:healthy_shard?).with('default').and_return(true)
+        end
+
+        it_behaves_like 'DesignRepositoryUpdatedEvent'
+
+        it 'schedules a Geo::DesignRepositorySyncWorker' do
+          expect(Geo::DesignRepositorySyncWorker).to receive(:perform_async).with(project.id).once
+
+          subject.process
+        end
+      end
+
+      context 'when associated shard is unhealthy' do
+        before do
+          allow(Gitlab::ShardHealthCache).to receive(:healthy_shard?).with('default').and_return(false)
+        end
+
+        it_behaves_like 'DesignRepositoryUpdatedEvent'
+
+        it 'does not schedule a Geo::DesignRepositorySyncWorker job' do
+          expect(Geo::DesignRepositorySyncWorker).not_to receive(:perform_async).with(project.id)
+
+          subject.process
+        end
+      end
+    end
+  end
+end