Refactor controller-manager volume plugins

Most of the volume plugins were removed from k/k. Refactor how KCM
controllers initialize the few leftovers.

Author: jsafrane

cmd/kube-controller-manager/app/core.go

@@ -270,7 +270,7 @@ func newPersistentVolumeBinderControllerDescriptor() *ControllerDescriptor {
 
 func startPersistentVolumeBinderController(ctx context.Context, controllerContext ControllerContext, controllerName string) (controller.Interface, bool, error) {
 	logger := klog.FromContext(ctx)
-	plugins, err := ProbeControllerVolumePlugins(logger, controllerContext.ComponentConfig.PersistentVolumeBinderController.VolumeConfiguration)
+	plugins, err := ProbeProvisionableRecyclableVolumePlugins(logger, controllerContext.ComponentConfig.PersistentVolumeBinderController.VolumeConfiguration)
 	if err != nil {
 		return nil, true, fmt.Errorf("failed to probe volume plugins when starting persistentvolume controller: %v", err)
 	}
@@ -307,7 +307,7 @@ func startPersistentVolumeAttachDetachController(ctx context.Context, controller
 	csiNodeInformer := controllerContext.InformerFactory.Storage().V1().CSINodes()
 	csiDriverInformer := controllerContext.InformerFactory.Storage().V1().CSIDrivers()
 
-	plugins, err := ProbeAttachableVolumePlugins(logger)
+	plugins, err := ProbeAttachableVolumePlugins(logger, controllerContext.ComponentConfig.PersistentVolumeBinderController.VolumeConfiguration)
 	if err != nil {
 		return nil, true, fmt.Errorf("failed to probe volume plugins when starting attach/detach controller: %v", err)
 	}

cmd/kube-controller-manager/app/plugins.go

@@ -24,14 +24,14 @@ import (
 	"fmt"
 
 	"k8s.io/klog/v2"
+	"k8s.io/kubernetes/pkg/volume/csi"
+	"k8s.io/kubernetes/pkg/volume/iscsi"
 
 	// Volume plugins
 	"k8s.io/kubernetes/pkg/volume"
-	"k8s.io/kubernetes/pkg/volume/csi"
 	"k8s.io/kubernetes/pkg/volume/fc"
 	"k8s.io/kubernetes/pkg/volume/flexvolume"
 	"k8s.io/kubernetes/pkg/volume/hostpath"
-	"k8s.io/kubernetes/pkg/volume/iscsi"
 	"k8s.io/kubernetes/pkg/volume/nfs"
 	volumeutil "k8s.io/kubernetes/pkg/volume/util"
 
@@ -42,14 +42,11 @@ import (
 
 // ProbeAttachableVolumePlugins collects all volume plugins for the attach/
 // detach controller.
-// The list of plugins is manually compiled. This code and the plugin
-// initialization code for kubelet really, really need a through refactor.
-func ProbeAttachableVolumePlugins(logger klog.Logger) ([]volume.VolumePlugin, error) {
-	allPlugins := []volume.VolumePlugin{}
-	allPlugins = append(allPlugins, fc.ProbeVolumePlugins()...)
-	allPlugins = append(allPlugins, iscsi.ProbeVolumePlugins()...)
-	allPlugins = append(allPlugins, csi.ProbeVolumePlugins()...)
-	return allPlugins, nil
+func ProbeAttachableVolumePlugins(logger klog.Logger, config persistentvolumeconfig.VolumeConfiguration) ([]volume.VolumePlugin, error) {
+	return probeControllerVolumePlugins(logger, config, func(plugin volume.VolumePlugin) bool {
+		_, ok := plugin.(volume.AttachableVolumePlugin)
+		return ok
+	})
 }
 
 // GetDynamicPluginProber gets the probers of dynamically discoverable plugins
@@ -61,20 +58,31 @@ func GetDynamicPluginProber(config persistentvolumeconfig.VolumeConfiguration) v
 
 // ProbeExpandableVolumePlugins returns volume plugins which are expandable
 func ProbeExpandableVolumePlugins(logger klog.Logger, config persistentvolumeconfig.VolumeConfiguration) ([]volume.VolumePlugin, error) {
-	var err error
-	allPlugins := []volume.VolumePlugin{}
-	allPlugins, err = appendExpandableLegacyProviderVolumes(logger, allPlugins, utilfeature.DefaultFeatureGate)
-	if err != nil {
-		return allPlugins, err
-	}
-	return allPlugins, nil
+	return probeControllerVolumePlugins(logger, config, func(plugin volume.VolumePlugin) bool {
+		_, ok := plugin.(volume.ExpandableVolumePlugin)
+		return ok
+	})
 }
 
-// ProbeControllerVolumePlugins collects all persistent volume plugins into an
-// easy to use list. Only volume plugins that implement any of
-// provisioner/recycler/deleter interface should be returned.
-func ProbeControllerVolumePlugins(logger klog.Logger, config persistentvolumeconfig.VolumeConfiguration) ([]volume.VolumePlugin, error) {
-	allPlugins := []volume.VolumePlugin{}
+func ProbeProvisionableRecyclableVolumePlugins(logger klog.Logger, config persistentvolumeconfig.VolumeConfiguration) ([]volume.VolumePlugin, error) {
+	return probeControllerVolumePlugins(logger, config, func(plugin volume.VolumePlugin) bool {
+		if _, ok := plugin.(volume.ProvisionableVolumePlugin); ok {
+			return true
+		}
+		if _, ok := plugin.(volume.DeletableVolumePlugin); ok {
+			return true
+		}
+		if _, ok := plugin.(volume.RecyclableVolumePlugin); ok {
+			return true
+		}
+		return false
+	})
+}
+
+// probeControllerVolumePlugins collects all persistent volume plugins
+// used by KCM controllers into an easy to use list.
+func probeControllerVolumePlugins(logger klog.Logger, config persistentvolumeconfig.VolumeConfiguration, filter func(plugin volume.VolumePlugin) bool) ([]volume.VolumePlugin, error) {
+	var allPlugins []volume.VolumePlugin
 
 	// The list of plugins to probe is decided by this binary, not
 	// by dynamic linking or other "magic".  Plugins will be analyzed and
@@ -107,14 +115,28 @@ func ProbeControllerVolumePlugins(logger klog.Logger, config persistentvolumecon
 		klog.FlushAndExit(klog.ExitFlushTimeout, 1)
 	}
 	allPlugins = append(allPlugins, nfs.ProbeVolumePlugins(nfsConfig)...)
+	allPlugins = append(allPlugins, fc.ProbeVolumePlugins()...)
+	allPlugins = append(allPlugins, iscsi.ProbeVolumePlugins()...)
+	allPlugins = append(allPlugins, csi.ProbeVolumePlugins()...)
 
 	var err error
-	allPlugins, err = appendExpandableLegacyProviderVolumes(logger, allPlugins, utilfeature.DefaultFeatureGate)
+	allPlugins, err = appendLegacyControllerProviders(logger, allPlugins, utilfeature.DefaultFeatureGate)
 	if err != nil {
 		return allPlugins, err
 	}
 
-	return allPlugins, nil
+	var filteredPlugins []volume.VolumePlugin
+	if filter == nil {
+		filteredPlugins = allPlugins
+	} else {
+		for _, plugin := range allPlugins {
+			if filter(plugin) {
+				filteredPlugins = append(filteredPlugins, plugin)
+			}
+		}
+	}
+
+	return filteredPlugins, nil
 }
 
 // AttemptToLoadRecycler tries decoding a pod from a filepath for use as a recycler for a volume.

cmd/kube-controller-manager/app/plugins_providers.go

@@ -53,7 +53,7 @@ type pluginInfo struct {
 	pluginProbeFunction     probeFn
 }
 
-func appendExpandableLegacyProviderVolumes(logger klog.Logger, allPlugins []volume.VolumePlugin, featureGate featuregate.FeatureGate) ([]volume.VolumePlugin, error) {
+func appendLegacyControllerProviders(logger klog.Logger, allPlugins []volume.VolumePlugin, featureGate featuregate.FeatureGate) ([]volume.VolumePlugin, error) {
 	pluginMigrationStatus := make(map[string]pluginInfo)
 	pluginMigrationStatus[plugins.PortworxVolumePluginName] = pluginInfo{pluginMigrationFeature: features.CSIMigrationPortworx, pluginUnregisterFeature: features.InTreePluginPortworxUnregister, pluginProbeFunction: portworx.ProbeVolumePlugins}
 	var err error

cmd/kube-controller-manager/app/plugins_test.go

@@ -40,7 +40,7 @@ func checkPlugins(t *testing.T, got []volume.VolumePlugin, expected []string) {
 
 func TestProbeAttachableVolumePlugins(t *testing.T) {
 	logger, _ := ktesting.NewTestContext(t)
-	plugins, err := ProbeAttachableVolumePlugins(logger)
+	plugins, err := ProbeAttachableVolumePlugins(logger, getConfig())
 	if err != nil {
 		t.Fatalf("ProbeAttachableVolumePlugins failed: %s", err)
 	}
@@ -58,7 +58,7 @@ func TestProbeExpandableVolumePlugins(t *testing.T) {
 
 func TestProbeControllerVolumePlugins(t *testing.T) {
 	logger, _ := ktesting.NewTestContext(t)
-	plugins, err := ProbeControllerVolumePlugins(logger, getConfig())
+	plugins, err := ProbeProvisionableRecyclableVolumePlugins(logger, getConfig())
 	if err != nil {
 		t.Fatalf("ProbeControllerVolumePlugins failed: %s", err)
 	}