Guard pages legacy storage lease by feature flag

app/services/pages/legacy_storage_lease.rb

@@ -8,6 +8,15 @@ module Pages
 
     LEASE_TIMEOUT = 1.hour
 
+    # override method from exclusive lease guard to guard it by feature flag
+    # TODO: just remove this method after testing this in production
+    # https://gitlab.com/gitlab-org/gitlab/-/issues/282464
+    def try_obtain_lease
+      return yield unless Feature.enabled?(:pages_use_legacy_storage_lease, project)
+
+      super
+    end
+
     def lease_key
       "pages_legacy_storage:#{project.id}"
     end

config/feature_flags/development/pages_use_legacy_storage_lease.yml

+---
+name: pages_use_legacy_storage_lease
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/48349
+rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/282464
+milestone: '13.7'
+type: development
+group: group::release
+default_enabled: false

spec/services/pages/legacy_storage_lease_spec.rb

@@ -30,9 +30,9 @@ RSpec.describe ::Pages::LegacyStorageLease do
   let(:service) { implementation.new(project) }
 
   it 'allows method to be executed' do
-    expect(service).to receive :execute_unsafe
+    expect(service).to receive(:execute_unsafe).and_call_original
 
-    service.execute
+    expect(service.execute).to eq(true)
   end
 
   context 'when another service holds the lease for the same project' do
@@ -47,6 +47,14 @@ RSpec.describe ::Pages::LegacyStorageLease do
 
       expect(service.execute).to eq(nil)
     end
+
+    it 'runs guarded method if feature flag is disabled' do
+      stub_feature_flags(pages_use_legacy_storage_lease: false)
+
+      expect(service).to receive(:execute_unsafe).and_call_original
+
+      expect(service.execute).to eq(true)
+    end
   end
 
   context 'when another service holds the lease for the different project' do