Plumb CSI listers through to backup controller

Account for having CSI enabled or not, as well as having the snapshot
CRDs installed in the kubernetes cluster.

Signed-off-by: Nolan Brubaker <brubakern@vmware.com>

pkg/cmd/server/server.go

@@ -43,8 +43,10 @@ import (
 	"k8s.io/client-go/rest"
 	"k8s.io/client-go/tools/cache"
 
-	snapshotter "github.com/kubernetes-csi/external-snapshotter/v2/pkg/client/clientset/versioned"
-	snapshotv1beta1 "github.com/kubernetes-csi/external-snapshotter/v2/pkg/client/clientset/versioned/typed/volumesnapshot/v1beta1"
+	snapshotv1beta1api "github.com/kubernetes-csi/external-snapshotter/v2/pkg/apis/volumesnapshot/v1beta1"
+	snapshotvebeta1client "github.com/kubernetes-csi/external-snapshotter/v2/pkg/client/clientset/versioned"
+	snapshotvebeta1informers "github.com/kubernetes-csi/external-snapshotter/v2/pkg/client/informers/externalversions"
+	snapshotv1beta1listers "github.com/kubernetes-csi/external-snapshotter/v2/pkg/client/listers/volumesnapshot/v1beta1"
 
 	api "github.com/vmware-tanzu/velero/pkg/apis/velero/v1"
 	"github.com/vmware-tanzu/velero/pkg/backup"
@@ -215,24 +217,25 @@ func NewCommand(f client.Factory) *cobra.Command {
 }
 
 type server struct {
-	namespace             string
-	metricsAddress        string
-	kubeClientConfig      *rest.Config
-	kubeClient            kubernetes.Interface
-	veleroClient          clientset.Interface
-	csiSnapClient         snapshotter.Interface
-	discoveryClient       discovery.DiscoveryInterface
-	discoveryHelper       velerodiscovery.Helper
-	dynamicClient         dynamic.Interface
-	sharedInformerFactory informers.SharedInformerFactory
-	ctx                   context.Context
-	cancelFunc            context.CancelFunc
-	logger                logrus.FieldLogger
-	logLevel              logrus.Level
-	pluginRegistry        clientmgmt.Registry
-	resticManager         restic.RepositoryManager
-	metrics               *metrics.ServerMetrics
-	config                serverConfig
+	namespace                        string
+	metricsAddress                   string
+	kubeClientConfig                 *rest.Config
+	kubeClient                       kubernetes.Interface
+	veleroClient                     clientset.Interface
+	csiSnapClient                    snapshotvebeta1client.Interface
+	discoveryClient                  discovery.DiscoveryInterface
+	discoveryHelper                  velerodiscovery.Helper
+	dynamicClient                    dynamic.Interface
+	sharedInformerFactory            informers.SharedInformerFactory
+	snapshotterSharedInformerFactory snapshotvebeta1informers.SharedInformerFactory
+	ctx                              context.Context
+	cancelFunc                       context.CancelFunc
+	logger                           logrus.FieldLogger
+	logLevel                         logrus.Level
+	pluginRegistry                   clientmgmt.Registry
+	resticManager                    restic.RepositoryManager
+	metrics                          *metrics.ServerMetrics
+	config                           serverConfig
 }
 
 func newServer(f client.Factory, config serverConfig, logger *logrus.Logger) (*server, error) {
@@ -270,9 +273,19 @@ func newServer(f client.Factory, config serverConfig, logger *logrus.Logger) (*s
 
 	clientConfig, err := f.ClientConfig()
 	if err != nil {
+		cancelFunc()
 		return nil, err
 	}
 
+	var csiSnapClient *snapshotvebeta1client.Clientset
+	if features.IsEnabled("EnableCSI") {
+		csiSnapClient, err = snapshotvebeta1client.NewForConfig(clientConfig)
+		if err != nil {
+			cancelFunc()
+			return nil, err
+		}
+	}
+
 	s := &server{
 		namespace:             f.Namespace(),
 		metricsAddress:        config.metricsAddress,
@@ -282,12 +295,15 @@ func newServer(f client.Factory, config serverConfig, logger *logrus.Logger) (*s
 		discoveryClient:       veleroClient.Discovery(),
 		dynamicClient:         dynamicClient,
 		sharedInformerFactory: informers.NewSharedInformerFactoryWithOptions(veleroClient, 0, informers.WithNamespace(f.Namespace())),
-		ctx:                   ctx,
-		cancelFunc:            cancelFunc,
-		logger:                logger,
-		logLevel:              logger.Level,
-		pluginRegistry:        pluginRegistry,
-		config:                config,
+		// If no namespace is specified, all namespaces are watched.
+		// This is desirable for VolumeSnapshots, as we want to query for all VolumeSnapshots across all namespaces using this informer
+		snapshotterSharedInformerFactory: snapshotvebeta1informers.NewSharedInformerFactoryWithOptions(csiSnapClient, 0),
+		ctx:                              ctx,
+		cancelFunc:                       cancelFunc,
+		logger:                           logger,
+		logLevel:                         logger.Level,
+		pluginRegistry:                   pluginRegistry,
+		config:                           config,
 	}
 
 	return s, nil
@@ -588,6 +604,27 @@ func (s *server) runControllers(defaultVolumeSnapshotLocations map[string]string
 		)
 		cmd.CheckError(err)
 
+		// Make empty listers that will only be populated if CSI is properly enabled.
+		var vsLister snapshotv1beta1listers.VolumeSnapshotLister
+		var vscLister snapshotv1beta1listers.VolumeSnapshotContentLister
+
+		// We don't care about the returned types, just whether or not there's a 404 error.
+		_, err = s.discoveryClient.ServerResourcesForGroupVersion(snapshotv1beta1api.SchemeGroupVersion.String())
+		switch {
+		case apierrors.IsNotFound(err) && !features.IsEnabled("EnableCSI"):
+			// Normal operating mode - CSI isn't enabled, so don't actually error
+		case apierrors.IsNotFound(err) && features.IsEnabled("EnableCSI"):
+			// CSI is enabled, but the required CRDs aren't installed, so halt.
+			s.logger.Fatalf("The 'EnableCSI' feature flag was specified, but CSI API group [%s] was not found.", snapshotv1beta1api.SchemeGroupVersion.String())
+		case err == nil && features.IsEnabled("EnableCSI"):
+			// CSI is enabled, and the resources were found.
+			// Instantiate the listers fully
+			vsLister = s.snapshotterSharedInformerFactory.Snapshot().V1beta1().VolumeSnapshots().Lister()
+			vscLister = s.snapshotterSharedInformerFactory.Snapshot().V1beta1().VolumeSnapshotContents().Lister()
+		case err != nil:
+			cmd.CheckError(err)
+		}
+
 		backupController := controller.NewBackupController(
 			s.sharedInformerFactory.Velero().V1().Backups(),
 			s.veleroClient.VeleroV1(),
@@ -605,6 +642,8 @@ func (s *server) runControllers(defaultVolumeSnapshotLocations map[string]string
 			defaultVolumeSnapshotLocations,
 			s.metrics,
 			s.config.formatFlag.Parse(),
+			vsLister,
+			vscLister,
 		)
 
 		return controllerRunInfo{
@@ -793,10 +832,17 @@ func (s *server) runControllers(defaultVolumeSnapshotLocations map[string]string
 
 	// start the informers & and wait for the caches to sync
 	s.sharedInformerFactory.Start(ctx.Done())
+	s.snapshotterSharedInformerFactory.Start(ctx.Done())
 	s.logger.Info("Waiting for informer caches to sync")
 	cacheSyncResults := s.sharedInformerFactory.WaitForCacheSync(ctx.Done())
+	csiCacheSyncResults := s.snapshotterSharedInformerFactory.WaitForCacheSync(ctx.Done())
 	s.logger.Info("Done waiting for informer caches to sync")
 
+	// Append our CSI informer types into the larger list of caches, so we can check them all at once
+	for informer, synced := range csiCacheSyncResults {
+		cacheSyncResults[informer] = synced
+	}
+
 	for informer, synced := range cacheSyncResults {
 		if !synced {
 			return errors.Errorf("cache was not synced for informer %v", informer)
@@ -837,18 +883,3 @@ func (s *server) runProfiler() {
 		s.logger.WithError(errors.WithStack(err)).Error("error running profiler http server")
 	}
 }
-
-// Helper methods that only return clients if the user has turned on CSI.
-func volumeSnapshotClientIfCSIEnabled(i snapshotter.Interface) snapshotv1beta1.VolumeSnapshotInterface {
-	if features.IsEnabled("EnableCSI") {
-		return i.SnapshotV1beta1().VolumeSnapshots("") // is this correct? we need the namespace? Could we get this lazily later, via the backup?
-	}
-	return nil
-}
-
-func voluemSnapshotContentClientIfCSIEnabled(i snapshotter.Interface) snapshotv1beta1.VolumeSnapshotContentInterface {
-	if features.IsEnabled("EnableCSI") {
-		return i.SnapshotV1beta1().VolumeSnapshotContents()
-	}
-	return nil
-}