per-volume ephemeral mode

This removes the limitation that the driver can only be deployed for
one mode or the other. Instead the driver depends on the new
csi.storage.k8s.io/ephemeral
field (kubernetes/kubernetes#79624) in the
volume context to determine how it should behave in NodePublishVolume.

The --ephemeral parameter is deprecated and will trigger a warning
when still used.

Supporting both modes in the same deployment makes it possible to test
ephemeral mode without having to change how the Prow jobs deploy the
driver, which is once as part of the cluster setup.

cmd/hostpathplugin/main.go

@@ -23,6 +23,7 @@ import (
 	"path"
 
 	"github.com/kubernetes-csi/csi-driver-host-path/pkg/hostpath"
+	"github.com/kubernetes-csi/csi-lib-utils/deprecatedflags"
 )
 
 func init() {
@@ -33,7 +34,7 @@ var (
 	endpoint    = flag.String("endpoint", "unix://tmp/csi.sock", "CSI endpoint")
 	driverName  = flag.String("drivername", "hostpath.csi.k8s.io", "name of the driver")
 	nodeID      = flag.String("nodeid", "", "node id")
-	ephemeral   = flag.Bool("ephemeral", false, "deploy in ephemeral mode")
+	_           = deprecatedflags.Add("ephemeral")
 	showVersion = flag.Bool("version", false, "Show version.")
 	// Set by the build process
 	version = ""
@@ -53,7 +54,7 @@ func main() {
 }
 
 func handle() {
-	driver, err := hostpath.NewHostPathDriver(*driverName, *nodeID, *endpoint, version, *ephemeral)
+	driver, err := hostpath.NewHostPathDriver(*driverName, *nodeID, *endpoint, version)
 	if err != nil {
 		fmt.Printf("Failed to initialize driver: %s", err.Error())
 		os.Exit(1)

deploy/kubernetes-1.14/hostpath/csi-hostpath-plugin.yaml

@@ -136,3 +136,10 @@ spec:
             path: /var/lib/csi-hostpath-data/
             type: DirectoryOrCreate
           name: csi-data-dir
+---
+apiVersion: storage.k8s.io/v1beta1
+kind: CSIDriver
+metadata:
+  name: hostpath.csi.k8s.io
+spec:
+  podInfoOnMount: true

pkg/hostpath/controllerserver.go

@@ -55,10 +55,7 @@ type controllerServer struct {
 	caps []*csi.ControllerServiceCapability
 }
 
-func NewControllerServer(ephemeral bool) *controllerServer {
-	if ephemeral {
-		return &controllerServer{caps: getControllerServiceCapabilities(nil)}
-	}
+func NewControllerServer() *controllerServer {
 	return &controllerServer{
 		caps: getControllerServiceCapabilities(
 			[]csi.ControllerServiceCapability_RPC_Type{
@@ -167,7 +164,7 @@ func (cs *controllerServer) CreateVolume(ctx context.Context, req *csi.CreateVol
 		}
 	}
 
-	vol, err := createHostpathVolume(volumeID, req.GetName(), capacity, requestedAccessType)
+	vol, err := createHostpathVolume(volumeID, req.GetName(), capacity, requestedAccessType, false /* ephemeral */)
 	if err != nil {
 		return nil, status.Error(codes.Internal, fmt.Sprintf("failed to create volume: %s", err))
 	}

pkg/hostpath/hostpath.go

@@ -36,11 +36,10 @@ const (
 )
 
 type hostPath struct {
-	name      string
-	nodeID    string
-	version   string
-	endpoint  string
-	ephemeral bool
+	name     string
+	nodeID   string
+	version  string
+	endpoint string
 
 	ids *identityServer
 	ns  *nodeServer
@@ -53,6 +52,7 @@ type hostPathVolume struct {
 	VolSize       int64      `json:"volSize"`
 	VolPath       string     `json:"volPath"`
 	VolAccessType accessType `json:"volAccessType"`
+	Ephemeral     bool       `json:"ephemeral"`
 }
 
 type hostPathSnapshot struct {
@@ -77,7 +77,7 @@ func init() {
 	hostPathVolumeSnapshots = map[string]hostPathSnapshot{}
 }
 
-func NewHostPathDriver(driverName, nodeID, endpoint, version string, ephemeral bool) (*hostPath, error) {
+func NewHostPathDriver(driverName, nodeID, endpoint, version string) (*hostPath, error) {
 	if driverName == "" {
 		return nil, fmt.Errorf("No driver name provided")
 	}
@@ -97,19 +97,18 @@ func NewHostPathDriver(driverName, nodeID, endpoint, version string, ephemeral b
 	glog.Infof("Version: %s", vendorVersion)
 
 	return &hostPath{
-		name:      driverName,
-		version:   vendorVersion,
-		nodeID:    nodeID,
-		endpoint:  endpoint,
-		ephemeral: ephemeral,
+		name:     driverName,
+		version:  vendorVersion,
+		nodeID:   nodeID,
+		endpoint: endpoint,
 	}, nil
 }
 
 func (hp *hostPath) Run() {
 	// Create GRPC servers
 	hp.ids = NewIdentityServer(hp.name, hp.version)
-	hp.ns = NewNodeServer(hp.nodeID, hp.ephemeral)
-	hp.cs = NewControllerServer(hp.ephemeral)
+	hp.ns = NewNodeServer(hp.nodeID)
+	hp.cs = NewControllerServer()
 
 	s := NewNonBlockingGRPCServer()
 	s.Start(hp.endpoint, hp.ids, hp.cs, hp.ns)
@@ -148,7 +147,7 @@ func getVolumePath(volID string) string {
 
 // createVolume create the directory for the hostpath volume.
 // It returns the volume path or err if one occurs.
-func createHostpathVolume(volID, name string, cap int64, volAccessType accessType) (*hostPathVolume, error) {
+func createHostpathVolume(volID, name string, cap int64, volAccessType accessType, ephemeral bool) (*hostPathVolume, error) {
 	path := getVolumePath(volID)
 	if volAccessType == mountAccess {
 		err := os.MkdirAll(path, 0777)
@@ -163,6 +162,7 @@ func createHostpathVolume(volID, name string, cap int64, volAccessType accessTyp
 		VolSize:       cap,
 		VolPath:       path,
 		VolAccessType: volAccessType,
+		Ephemeral:     ephemeral,
 	}
 	hostPathVolumes[volID] = hostpathVol
 	return &hostpathVol, nil

pkg/hostpath/nodeserver.go

@@ -32,14 +32,12 @@ import (
 )
 
 type nodeServer struct {
-	nodeID    string
-	ephemeral bool
+	nodeID string
 }
 
-func NewNodeServer(nodeId string, ephemeral bool) *nodeServer {
+func NewNodeServer(nodeId string) *nodeServer {
 	return &nodeServer{
-		nodeID:    nodeId,
-		ephemeral: ephemeral,
+		nodeID: nodeId,
 	}
 }
 
@@ -57,17 +55,18 @@ func (ns *nodeServer) NodePublishVolume(ctx context.Context, req *csi.NodePublis
 	}
 
 	targetPath := req.GetTargetPath()
+	ephemeralVolume := req.GetVolumeContext()["csi.storage.k8s.io/ephemeral"] == "true"
 
 	if req.GetVolumeCapability().GetBlock() != nil &&
 		req.GetVolumeCapability().GetMount() != nil {
 		return nil, status.Error(codes.InvalidArgument, "cannot have both block and mount access type")
 	}
 
 	// if ephemeral is specified, create volume here to avoid errors
-	if ns.ephemeral {
+	if ephemeralVolume {
 		volID := req.GetVolumeId()
 		volName := fmt.Sprintf("ephemeral-%s", volID)
-		vol, err := createHostpathVolume(req.GetVolumeId(), volName, maxStorageCapacity, mountAccess)
+		vol, err := createHostpathVolume(req.GetVolumeId(), volName, maxStorageCapacity, mountAccess, ephemeralVolume)
 		if err != nil && !os.IsExist(err) {
 			glog.Error("ephemeral mode failed to create volume: ", err)
 			return nil, status.Error(codes.Internal, err.Error())
@@ -170,7 +169,7 @@ func (ns *nodeServer) NodePublishVolume(ctx context.Context, req *csi.NodePublis
 		if err := mounter.Mount(path, targetPath, "", options); err != nil {
 			var errList strings.Builder
 			errList.WriteString(err.Error())
-			if ns.ephemeral {
+			if vol.Ephemeral {
 				if rmErr := os.RemoveAll(path); rmErr != nil && !os.IsNotExist(rmErr) {
 					errList.WriteString(fmt.Sprintf(" :%s", rmErr.Error()))
 				}
@@ -218,7 +217,7 @@ func (ns *nodeServer) NodeUnpublishVolume(ctx context.Context, req *csi.NodeUnpu
 		glog.V(4).Infof("hostpath: volume %s/%s has been unmounted.", targetPath, volumeID)
 	}
 
-	if ns.ephemeral {
+	if vol.Ephemeral {
 		glog.V(4).Infof("deleting volume %s", volumeID)
 		if err := deleteHostpathVolume(volumeID); err != nil && !os.IsNotExist(err) {
 			return nil, status.Error(codes.Internal, fmt.Sprintf("failed to delete volume: %s", err))