fix: CNS init must have an NC (#2030)

Signed-off-by: Evan Baker <rbtr@users.noreply.github.com>

cns/restserver/internalapi.go

@@ -276,7 +276,7 @@ func (service *HTTPRestService) syncHostNCVersion(ctx context.Context, channelMo
 
 // This API will be called by CNS RequestController on CRD update.
 func (service *HTTPRestService) ReconcileNCState(ncRequest *cns.CreateNetworkContainerRequest, podInfoByIP map[string]cns.PodInfo, nnc *v1alpha.NodeNetworkConfig) types.ResponseCode {
-	logger.Printf("Reconciling NC state with podInfo %+v", podInfoByIP)
+	logger.Printf("Reconciling NC state with CreateNCRequest: [%v], PodInfo [%+v], NNC: [%+v]", ncRequest, podInfoByIP, nnc)
 	// check if ncRequest is null, then return as there is no CRD state yet
 	if ncRequest == nil {
 		logger.Printf("CNS starting with no NC state, podInfoMap count %d", len(podInfoByIP))

cns/service/main.go

@@ -54,6 +54,7 @@ import (
 	"github.com/avast/retry-go/v3"
 	"github.com/pkg/errors"
 	"go.uber.org/zap"
+	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"
@@ -1022,28 +1023,21 @@ func reconcileInitialCNSState(ctx context.Context, cli nodeNetworkConfigGetter,
 	// Get nnc using direct client
 	nnc, err := cli.Get(ctx)
 	if err != nil {
-
 		if crd.IsNotDefined(err) {
-			return errors.Wrap(err, "failed to get NNC during init CNS state")
+			return errors.Wrap(err, "failed to init CNS state: NNC CRD is not defined")
 		}
-
-		// If instance of crd is not found, pass nil to CNSClient
-		if client.IgnoreNotFound(err) == nil {
-			err = restserver.ResponseCodeToError(ncReconciler.ReconcileNCState(nil, nil, nnc))
-			return errors.Wrap(err, "failed to reconcile NC state")
+		if apierrors.IsNotFound(err) {
+			return errors.Wrap(err, "failed to init CNS state: NNC not found")
 		}
-
-		// If it's any other error, log it and return
-		return errors.Wrap(err, "error getting NodeNetworkConfig when initializing CNS state")
+		return errors.Wrap(err, "failed to init CNS state: failed to get NNC CRD")
 	}
 
-	// If there are no NCs, pass nil to CNSClient
+	// If there are no NCs, we can't initialize our state and we should fail out.
 	if len(nnc.Status.NetworkContainers) == 0 {
-		err = restserver.ResponseCodeToError(ncReconciler.ReconcileNCState(nil, nil, nnc))
-		return errors.Wrap(err, "failed to reconcile NC state")
+		return errors.Wrap(err, "failed to init CNS state: no NCs found in NNC CRD")
 	}
 
-	// Convert to CreateNetworkContainerRequest
+	// For each NC, we need to create a CreateNetworkContainerRequest and use it to rebuild our state.
 	for i := range nnc.Status.NetworkContainers {
 		var ncRequest *cns.CreateNetworkContainerRequest
 		var err error
@@ -1059,8 +1053,7 @@ func reconcileInitialCNSState(ctx context.Context, cli nodeNetworkConfigGetter,
 			return errors.Wrapf(err, "failed to convert NNC status to network container request, "+
 				"assignmentMode: %s", nnc.Status.NetworkContainers[i].AssignmentMode)
 		}
-
-		// rebuild CNS state
+		// Get previous PodInfo state from podInfoByIPProvider
 		podInfoByIP, err := podInfoByIPProvider.PodInfoByIP()
 		if err != nil {
 			return errors.Wrap(err, "provider failed to provide PodInfoByIP")