fix: init NNC from reconciler instead of directly

Author: rbtr

cns/kubecontroller/nodenetworkconfig/reconciler.go

@@ -27,8 +27,10 @@ type cnsClient interface {
 	MustEnsureNoStaleNCs(validNCIDs []string)
 }
 
+type nodenetworkconfigSink func(*v1alpha.NodeNetworkConfig) error
+
 type nodeNetworkConfigListener interface {
-	Update(*v1alpha.NodeNetworkConfig) error
+	Update(*v1alpha.NodeNetworkConfig) error // phasing this out in favor of the sink
 }
 
 type nncGetter interface {
@@ -38,31 +40,33 @@ type nncGetter interface {
 // Reconciler watches for CRD status changes
 type Reconciler struct {
 	cnscli             cnsClient
-	ipampoolmonitorcli nodeNetworkConfigListener
+	ipampoolmonitorcli nodenetworkconfigSink
 	nnccli             nncGetter
 	once               sync.Once
-	started            chan interface{}
+	started            chan any
 	nodeIP             string
 	isSwiftV2          bool
+	initializer        nodenetworkconfigSink
 }
 
 // NewReconciler creates a NodeNetworkConfig Reconciler which will get updates from the Kubernetes
 // apiserver for NNC events.
 // Provided nncListeners are passed the NNC after the Reconcile preprocesses it. Note: order matters! The
 // passed Listeners are notified in the order provided.
-func NewReconciler(cnscli cnsClient, ipampoolmonitorcli nodeNetworkConfigListener, nodeIP string, isSwiftV2 bool) *Reconciler {
+func NewReconciler(cnscli cnsClient, initializer nodenetworkconfigSink,  ipampoolmonitorcli nodeNetworkConfigListener, nodeIP string, isSwiftV2 bool) *Reconciler {
 	return &Reconciler{
 		cnscli:             cnscli,
-		ipampoolmonitorcli: ipampoolmonitorcli,
-		started:            make(chan interface{}),
+		ipampoolmonitorcli: ipampoolmonitorcli.Update,
+		started:            make(chan any),
 		nodeIP:             nodeIP,
 		isSwiftV2:          isSwiftV2,
+		initializer:        initializer,
 	}
 }
 
 // Reconcile is called on CRD status changes
 func (r *Reconciler) Reconcile(ctx context.Context, req reconcile.Request) (reconcile.Result, error) {
-	listenersToNotify := []nodeNetworkConfigListener{}
+	listenersToNotify := []nodenetworkconfigSink{}
 	nnc, err := r.nnccli.Get(ctx, req.NamespacedName)
 	if err != nil {
 		if apierrors.IsNotFound(err) {
@@ -89,6 +93,12 @@ func (r *Reconciler) Reconcile(ctx context.Context, req reconcile.Request) (reco
 	}
 	r.cnscli.MustEnsureNoStaleNCs(validNCIDs)
 
+	// call initFunc on first reconcile
+	if err := r.initializer(nnc); err != nil {
+		logger.Errorf("[cns-rc] initializer failed during reconcile: %v", err)
+		return reconcile.Result{}, errors.Wrap(err, "initializer failed during reconcile")
+	}
+
 	// for each NC, parse it in to a CreateNCRequest and forward it to the appropriate Listener
 	for i := range nnc.Status.NetworkContainers {
 		// check if this NC matches the Node IP if we have one to check against
@@ -134,7 +144,7 @@ func (r *Reconciler) Reconcile(ctx context.Context, req reconcile.Request) (reco
 
 	// push the NNC to the registered NNC listeners.
 	for _, l := range listenersToNotify {
-		if err := l.Update(nnc); err != nil {
+		if err := l(nnc); err != nil {
 			return reconcile.Result{}, errors.Wrap(err, "nnc listener return error during update")
 		}
 	}

cns/kubecontroller/nodenetworkconfig/reconciler_test.go

@@ -192,7 +192,7 @@ func TestReconcile(t *testing.T) {
 		}
 
 		t.Run(tt.name, func(t *testing.T) {
-			r := NewReconciler(&tt.cnsClient, &tt.cnsClient, tt.nodeIP, false)
+			r := NewReconciler(&tt.cnsClient, func(*v1alpha.NodeNetworkConfig) error { return nil }, &tt.cnsClient, tt.nodeIP, false)
 			r.nnccli = &tt.ncGetter
 			got, err := r.Reconcile(context.Background(), tt.in)
 			if tt.wantErr {
@@ -249,7 +249,7 @@ func TestReconcileStaleNCs(t *testing.T) {
 		return &nncLog[len(nncLog)-1], nil
 	}
 
-	r := NewReconciler(&cnsClient, &cnsClient, nodeIP, false)
+	r := NewReconciler(&cnsClient, func(*v1alpha.NodeNetworkConfig) error { return nil }, &cnsClient, nodeIP, false)
 	r.nnccli = &mockNCGetter{get: nncIterator}
 
 	_, err := r.Reconcile(context.Background(), reconcile.Request{})

cns/service/main.go

@@ -52,7 +52,6 @@ import (
 	cnstypes "github.com/Azure/azure-container-networking/cns/types"
 	"github.com/Azure/azure-container-networking/cns/wireserver"
 	acn "github.com/Azure/azure-container-networking/common"
-	"github.com/Azure/azure-container-networking/crd"
 	"github.com/Azure/azure-container-networking/crd/clustersubnetstate"
 	cssv1alpha1 "github.com/Azure/azure-container-networking/crd/clustersubnetstate/api/v1alpha1"
 	"github.com/Azure/azure-container-networking/crd/multitenancy"
@@ -74,7 +73,6 @@ import (
 	"go.uber.org/zap"
 	"golang.org/x/time/rate"
 	corev1 "k8s.io/api/core/v1"
-	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/fields"
 	kuberuntime "k8s.io/apimachinery/pkg/runtime"
@@ -1307,37 +1305,17 @@ func InitializeMultiTenantController(ctx context.Context, httpRestService cns.HT
 	return nil
 }
 
-type nodeNetworkConfigGetter interface {
-	Get(context.Context) (*v1alpha.NodeNetworkConfig, error)
-}
-
 type ipamStateReconciler interface {
 	ReconcileIPAMStateForSwift(ncRequests []*cns.CreateNetworkContainerRequest, podInfoByIP map[string]cns.PodInfo, nnc *v1alpha.NodeNetworkConfig) cnstypes.ResponseCode
 }
 
 // TODO(rbtr) where should this live??
 // reconcileInitialCNSState initializes cns by passing pods and a CreateNetworkContainerRequest
-func reconcileInitialCNSState(ctx context.Context, cli nodeNetworkConfigGetter, ipamReconciler ipamStateReconciler, podInfoByIPProvider cns.PodInfoByIPProvider, isSwiftV2 bool) error {
-	// Get nnc using direct client
-	nnc, err := cli.Get(ctx)
-	if err != nil {
-		if crd.IsNotDefined(err) {
-			return errors.Wrap(err, "failed to init CNS state: NNC CRD is not defined")
-		}
-		if apierrors.IsNotFound(err) {
-			return errors.Wrap(err, "failed to init CNS state: NNC not found")
-		}
-		return errors.Wrap(err, "failed to init CNS state: failed to get NNC CRD")
-	}
-
-	logger.Printf("Retrieved NNC: %+v", nnc)
-	if !nnc.DeletionTimestamp.IsZero() {
-		return errors.New("failed to init CNS state: NNC is being deleted")
-	}
-
-	// If there are no NCs, we can't initialize our state and we should fail out.
-	if len(nnc.Status.NetworkContainers) == 0 {
-		return errors.New("failed to init CNS state: no NCs found in NNC CRD")
+func reconcileInitialCNSState(nnc *v1alpha.NodeNetworkConfig, ipamReconciler ipamStateReconciler, podInfoByIPProvider cns.PodInfoByIPProvider, isSwiftV2 bool) error {
+	// if no NCs, nothing to do
+	ncCount := len(nnc.Status.NetworkContainers)
+	if ncCount == 0 {
+		return errors.New("no network containers found in NNC status")
 	}
 
 	// Get previous PodInfo state from podInfoByIPProvider
@@ -1444,35 +1422,22 @@ func InitializeCRDState(ctx context.Context, z *zap.Logger, httpRestService cns.
 		return errors.Wrap(err, "failed to initialize ip state")
 	}
 
-	// create scoped kube clients.
-	directcli, err := client.New(kubeConfig, client.Options{Scheme: nodenetworkconfig.Scheme})
-	if err != nil {
-		return errors.Wrap(err, "failed to create ctrl client")
-	}
-	directnnccli := nodenetworkconfig.NewClient(directcli)
-	if err != nil {
-		return errors.Wrap(err, "failed to create NNC client")
-	}
-	// TODO(rbtr): nodename and namespace should be in the cns config
-	directscopedcli := nncctrl.NewScopedClient(directnnccli, types.NamespacedName{Namespace: "kube-system", Name: nodeName})
-
-	logger.Printf("Reconciling initial CNS state")
-	// apiserver nnc might not be registered or api server might be down and crashloop backof puts us outside of 5-10 minutes we have for
-	// aks addons to come up so retry a bit more aggresively here.
-	// will retry 10 times maxing out at a minute taking about 8 minutes before it gives up.
-	attempt := 0
-	_ = retry.Do(func() error {
-		attempt++
-		logger.Printf("reconciling initial CNS state attempt: %d", attempt)
-		err = reconcileInitialCNSState(ctx, directscopedcli, httpRestServiceImplementation, podInfoByIPProvider, cnsconfig.EnableSwiftV2)
-		if err != nil {
-			logger.Errorf("failed to reconcile initial CNS state, attempt: %d err: %v", attempt, err)
-			nncInitFailure.Inc()
+	
+	hasInitialized := false
+	initFunc := func(nnc *v1alpha.NodeNetworkConfig) error {
+		if hasInitialized {
+			return nil
 		}
-		return errors.Wrap(err, "failed to initialize CNS state")
-	}, retry.Context(ctx), retry.Delay(initCNSInitalDelay), retry.MaxDelay(time.Minute), retry.UntilSucceeded())
-	logger.Printf("reconciled initial CNS state after %d attempts", attempt)
-	hasNNCInitialized.Set(1)
+		logger.Printf("Reconciling initial CNS state")
+		if err := reconcileInitialCNSState(nnc, httpRestServiceImplementation, podInfoByIPProvider, cnsconfig.EnableSwiftV2); err != nil {
+			return err
+		}
+		hasNNCInitialized.Set(2)
+		hasInitialized = true
+		return nil
+	}
+
+	
 	scheme := kuberuntime.NewScheme()
 	if err := corev1.AddToScheme(scheme); err != nil { //nolint:govet // intentional shadow
 		return errors.Wrap(err, "failed to add corev1 to scheme")
@@ -1561,7 +1526,7 @@ func InitializeCRDState(ctx context.Context, z *zap.Logger, httpRestService cns.
 
 	// get CNS Node IP to compare NC Node IP with this Node IP to ensure NCs were created for this node
 	nodeIP := configuration.NodeIP()
-	nncReconciler := nncctrl.NewReconciler(httpRestServiceImplementation, poolMonitor, nodeIP, cnsconfig.EnableSwiftV2)
+	nncReconciler := nncctrl.NewReconciler(httpRestServiceImplementation, initFunc, poolMonitor, nodeIP, cnsconfig.EnableSwiftV2)
 	// pass Node to the Reconciler for Controller xref
 	// IPAMv1 - reconcile only status changes (where generation doesn't change).
 	// IPAMv2 - reconcile all updates.