Define TestableConfig in k/apiserver/pkg/util/flowcontrol

Collect the parameters of newTestableController into a named type.

Also tolerate the surprising situation in which a request's user
groups include neither `system:authenticated` nor
`system:unauthenticated` --- because this is observed to happen in
some tests.

Also a few other minor fixups.

staging/src/k8s.io/apiserver/pkg/util/flowcontrol/apf_controller.go

@@ -42,7 +42,6 @@ import (
 	fq "k8s.io/apiserver/pkg/util/flowcontrol/fairqueuing"
 	fcfmt "k8s.io/apiserver/pkg/util/flowcontrol/format"
 	"k8s.io/apiserver/pkg/util/flowcontrol/metrics"
-	kubeinformers "k8s.io/client-go/informers"
 	"k8s.io/client-go/tools/cache"
 	"k8s.io/client-go/util/workqueue"
 	"k8s.io/klog/v2"
@@ -61,7 +60,7 @@ import (
 // undesired becomes completely unused, all the config objects are
 // read and processed as a whole.
 
-// StartFunction begins the process of handlig a request.  If the
+// StartFunction begins the process of handling a request.  If the
 // request gets queued then this function uses the given hashValue as
 // the source of entropy as it shuffle-shards the request into a
 // queue.  The descr1 and descr2 values play no role in the logic but
@@ -151,34 +150,22 @@ type priorityLevelState struct {
 }
 
 // NewTestableController is extra flexible to facilitate testing
-func newTestableController(
-	informerFactory kubeinformers.SharedInformerFactory,
-	flowcontrolClient flowcontrolclient.FlowcontrolV1beta1Interface,
-	serverConcurrencyLimit int,
-	requestWaitLimit time.Duration,
-	obsPairGenerator metrics.TimedObserverPairGenerator,
-	queueSetFactory fq.QueueSetFactory,
-) *configController {
+func newTestableController(config TestableConfig) *configController {
 	cfgCtlr := &configController{
-		queueSetFactory:        queueSetFactory,
-		obsPairGenerator:       obsPairGenerator,
-		serverConcurrencyLimit: serverConcurrencyLimit,
-		requestWaitLimit:       requestWaitLimit,
-		flowcontrolClient:      flowcontrolClient,
+		queueSetFactory:        config.QueueSetFactory,
+		obsPairGenerator:       config.ObsPairGenerator,
+		serverConcurrencyLimit: config.ServerConcurrencyLimit,
+		requestWaitLimit:       config.RequestWaitLimit,
+		flowcontrolClient:      config.FlowcontrolClient,
 		priorityLevelStates:    make(map[string]*priorityLevelState),
 	}
-	klog.V(2).Infof("NewTestableController with serverConcurrencyLimit=%d, requestWaitLimit=%s", serverConcurrencyLimit, requestWaitLimit)
-	cfgCtlr.initializeConfigController(informerFactory)
+	klog.V(2).Infof("NewTestableController with serverConcurrencyLimit=%d, requestWaitLimit=%s", cfgCtlr.serverConcurrencyLimit, cfgCtlr.requestWaitLimit)
+	// Start with longish delay because conflicts will be between
+	// different processes, so take some time to go away.
+	cfgCtlr.configQueue = workqueue.NewNamedRateLimitingQueue(workqueue.NewItemExponentialFailureRateLimiter(200*time.Millisecond, 8*time.Hour), "priority_and_fairness_config_queue")
 	// ensure the data structure reflects the mandatory config
 	cfgCtlr.lockAndDigestConfigObjects(nil, nil)
-	return cfgCtlr
-}
-
-// initializeConfigController sets up the controller that processes
-// config API objects.
-func (cfgCtlr *configController) initializeConfigController(informerFactory kubeinformers.SharedInformerFactory) {
-	cfgCtlr.configQueue = workqueue.NewNamedRateLimitingQueue(workqueue.NewItemExponentialFailureRateLimiter(200*time.Millisecond, 8*time.Hour), "priority_and_fairness_config_queue")
-	fci := informerFactory.Flowcontrol().V1beta1()
+	fci := config.InformerFactory.Flowcontrol().V1beta1()
 	pli := fci.PriorityLevelConfigurations()
 	fsi := fci.FlowSchemas()
 	cfgCtlr.plLister = pli.Lister()
@@ -225,6 +212,7 @@ func (cfgCtlr *configController) initializeConfigController(informerFactory kube
 			cfgCtlr.configQueue.Add(0)
 
 		}})
+	return cfgCtlr
 }
 
 // MaintainObservations keeps the observers from
@@ -330,7 +318,7 @@ type cfgMeal struct {
 	fsStatusUpdates []fsStatusUpdate
 }
 
-// A buffered set of status updates for a FlowSchema
+// A buffered set of status updates for FlowSchemas
 type fsStatusUpdate struct {
 	flowSchema *flowcontrol.FlowSchema
 	condition  flowcontrol.FlowSchemaCondition
@@ -349,7 +337,7 @@ func (cfgCtlr *configController) digestConfigObjects(newPLs []*flowcontrol.Prior
 			panic(fmt.Sprintf("Failed to json.Marshall(%#+v): %s", fsu.condition, err.Error()))
 		}
 		klog.V(4).Infof("Writing Condition %s to FlowSchema %s because its previous value was %s", string(enc), fsu.flowSchema.Name, fcfmt.Fmt(fsu.oldValue))
-		_, err = cfgCtlr.flowcontrolClient.FlowSchemas().Patch(context.TODO(), fsu.flowSchema.Name, apitypes.StrategicMergePatchType, []byte(fmt.Sprintf(`{"status": {"conditions": [ %s ] } }`, string(enc))), metav1.PatchOptions{FieldManager: "api-priority-and-fairness-config-consumer-v1"}, "status")
+		_, err = cfgCtlr.flowcontrolClient.FlowSchemas().Patch(context.TODO(), fsu.flowSchema.Name, apitypes.StrategicMergePatchType, []byte(fmt.Sprintf(`{"status": {"conditions": [ %s ] } }`, string(enc))), metav1.PatchOptions{FieldManager: ConfigConsumerAsFieldManager}, "status")
 		if err != nil {
 			errs = append(errs, errors.Wrap(err, fmt.Sprintf("failed to set a status.condition for FlowSchema %s", fsu.flowSchema.Name)))
 		}
@@ -654,30 +642,28 @@ func (cfgCtlr *configController) startRequest(ctx context.Context, rd RequestDig
 	klog.V(7).Infof("startRequest(%#+v)", rd)
 	cfgCtlr.lock.Lock()
 	defer cfgCtlr.lock.Unlock()
-	var selectedFlowSchema *flowcontrol.FlowSchema
+	var selectedFlowSchema, catchAllFlowSchema *flowcontrol.FlowSchema
 	for _, fs := range cfgCtlr.flowSchemas {
 		if matchesFlowSchema(rd, fs) {
 			selectedFlowSchema = fs
 			break
 		}
+		if fs.Name == flowcontrol.FlowSchemaNameCatchAll {
+			catchAllFlowSchema = fs
+		}
 	}
 	if selectedFlowSchema == nil {
 		// This should never happen. If the requestDigest's User is a part of
 		// system:authenticated or system:unauthenticated, the catch-all flow
 		// schema should match it. However, if that invariant somehow fails,
 		// fallback to the catch-all flow schema anyway.
-		for _, fs := range cfgCtlr.flowSchemas {
-			if fs.Name == flowcontrol.FlowSchemaNameCatchAll {
-				selectedFlowSchema = fs
-				break
-			}
-		}
-		if selectedFlowSchema == nil {
+		if catchAllFlowSchema == nil {
 			// This should absolutely never, ever happen! APF guarantees two
 			// undeletable flow schemas at all times: an exempt flow schema and a
 			// catch-all flow schema.
 			panic(fmt.Sprintf("no fallback catch-all flow schema found for request %#+v and user %#+v", rd.RequestInfo, rd.User))
 		}
+		selectedFlowSchema = catchAllFlowSchema
 		klog.Warningf("no match found for request %#+v and user %#+v; selecting catchAll=%s as fallback flow schema", rd.RequestInfo, rd.User, fcfmt.Fmt(selectedFlowSchema))
 	}
 	plName := selectedFlowSchema.Spec.PriorityLevelConfiguration.Name

staging/src/k8s.io/apiserver/pkg/util/flowcontrol/apf_filter.go

@@ -34,6 +34,10 @@ import (
 	flowcontrolclient "k8s.io/client-go/kubernetes/typed/flowcontrol/v1beta1"
 )
 
+// ConfigConsumerAsFieldManager is how the config consuminng
+// controller appears in an ObjectMeta ManagedFieldsEntry.Manager
+const ConfigConsumerAsFieldManager = "api-priority-and-fairness-config-consumer-v1"
+
 // Interface defines how the API Priority and Fairness filter interacts with the underlying system.
 type Interface interface {
 	// Handle takes care of queuing and dispatching a request
@@ -74,26 +78,40 @@ func New(
 	requestWaitLimit time.Duration,
 ) Interface {
 	grc := counter.NoOp{}
-	return NewTestable(
-		informerFactory,
-		flowcontrolClient,
-		serverConcurrencyLimit,
-		requestWaitLimit,
-		metrics.PriorityLevelConcurrencyObserverPairGenerator,
-		fqs.NewQueueSetFactory(&clock.RealClock{}, grc),
-	)
+	return NewTestable(TestableConfig{
+		InformerFactory:        informerFactory,
+		FlowcontrolClient:      flowcontrolClient,
+		ServerConcurrencyLimit: serverConcurrencyLimit,
+		RequestWaitLimit:       requestWaitLimit,
+		ObsPairGenerator:       metrics.PriorityLevelConcurrencyObserverPairGenerator,
+		QueueSetFactory:        fqs.NewQueueSetFactory(&clock.RealClock{}, grc),
+	})
+}
+
+// TestableConfig carries the parameters to an implementation that is testable
+type TestableConfig struct {
+	// InformerFactory to use in building the controller
+	InformerFactory kubeinformers.SharedInformerFactory
+
+	// FlowcontrolClient to use for manipulating config objects
+	FlowcontrolClient flowcontrolclient.FlowcontrolV1beta1Interface
+
+	// ServerConcurrencyLimit for the controller to enforce
+	ServerConcurrencyLimit int
+
+	// RequestWaitLimit configured on the server
+	RequestWaitLimit time.Duration
+
+	// ObsPairGenerator for metrics
+	ObsPairGenerator metrics.TimedObserverPairGenerator
+
+	// QueueSetFactory for the queuing implementation
+	QueueSetFactory fq.QueueSetFactory
 }
 
 // NewTestable is extra flexible to facilitate testing
-func NewTestable(
-	informerFactory kubeinformers.SharedInformerFactory,
-	flowcontrolClient flowcontrolclient.FlowcontrolV1beta1Interface,
-	serverConcurrencyLimit int,
-	requestWaitLimit time.Duration,
-	obsPairGenerator metrics.TimedObserverPairGenerator,
-	queueSetFactory fq.QueueSetFactory,
-) Interface {
-	return newTestableController(informerFactory, flowcontrolClient, serverConcurrencyLimit, requestWaitLimit, obsPairGenerator, queueSetFactory)
+func NewTestable(config TestableConfig) Interface {
+	return newTestableController(config)
 }
 
 func (cfgCtlr *configController) Handle(ctx context.Context, requestDigest RequestDigest,

staging/src/k8s.io/apiserver/pkg/util/flowcontrol/controller_test.go

@@ -230,14 +230,14 @@ func TestConfigConsumer(t *testing.T) {
 				heldRequestsMap: map[string][]heldRequest{},
 				queues:          map[string]*ctlrTestQueueSet{},
 			}
-			ctlr := newTestableController(
-				informerFactory,
-				flowcontrolClient,
-				100,         // server concurrency limit
-				time.Minute, // request wait limit
-				metrics.PriorityLevelConcurrencyObserverPairGenerator,
-				cts,
-			)
+			ctlr := newTestableController(TestableConfig{
+				InformerFactory:        informerFactory,
+				FlowcontrolClient:      flowcontrolClient,
+				ServerConcurrencyLimit: 100,
+				RequestWaitLimit:       time.Minute,
+				ObsPairGenerator:       metrics.PriorityLevelConcurrencyObserverPairGenerator,
+				QueueSetFactory:        cts,
+			})
 			cts.cfgCtlr = ctlr
 			persistingPLNames := sets.NewString()
 			trialStep := fmt.Sprintf("trial%d-0", i)