integration test for priority-level isolation

test/integration/framework/master_utils.go

@@ -39,10 +39,13 @@ import (
 	"k8s.io/apiserver/pkg/authorization/authorizerfactory"
 	authorizerunion "k8s.io/apiserver/pkg/authorization/union"
 	openapinamer "k8s.io/apiserver/pkg/endpoints/openapi"
+	genericfeatures "k8s.io/apiserver/pkg/features"
 	genericapiserver "k8s.io/apiserver/pkg/server"
 	"k8s.io/apiserver/pkg/server/options"
 	serverstorage "k8s.io/apiserver/pkg/server/storage"
 	"k8s.io/apiserver/pkg/storage/storagebackend"
+	utilfeature "k8s.io/apiserver/pkg/util/feature"
+	utilflowcontrol "k8s.io/apiserver/pkg/util/flowcontrol"
 	"k8s.io/client-go/informers"
 	clientset "k8s.io/client-go/kubernetes"
 	restclient "k8s.io/client-go/rest"
@@ -191,6 +194,16 @@ func startMasterOrDie(masterConfig *master.Config, incomingServer *httptest.Serv
 	}
 
 	masterConfig.ExtraConfig.VersionedInformers = informers.NewSharedInformerFactory(clientset, masterConfig.GenericConfig.LoopbackClientConfig.Timeout)
+
+	if utilfeature.DefaultFeatureGate.Enabled(genericfeatures.APIPriorityAndFairness) {
+		masterConfig.GenericConfig.FlowControl = utilflowcontrol.New(
+			masterConfig.ExtraConfig.VersionedInformers,
+			clientset.FlowcontrolV1alpha1(),
+			masterConfig.GenericConfig.MaxRequestsInFlight+masterConfig.GenericConfig.MaxMutatingRequestsInFlight,
+			masterConfig.GenericConfig.RequestTimeout/4,
+		)
+	}
+
 	m, err = masterConfig.Complete().New(genericapiserver.NewEmptyDelegate())
 	if err != nil {
 		// We log the error first so that even if closeFn crashes, the error is shown