Hostpath fixes for ephemeral support (vladimirvivien)

Clean up nill pointer execptions
Return proper cabilities for ephemeral
Properly provision volume/delete volume during node operations
Refactor code volume operation code for reuse

Author: Vladimir Vivien

pkg/hostpath/controllerserver.go

@@ -37,7 +37,6 @@ import (
 
 const (
 	deviceID           = "deviceID"
-	provisionRoot      = "/tmp/"
 	snapshotRoot       = "/tmp/"
 	maxStorageCapacity = tib
 )
@@ -46,7 +45,10 @@ type controllerServer struct {
 	caps []*csi.ControllerServiceCapability
 }
 
-func NewControllerServer() *controllerServer {
+func NewControllerServer(ephemeral bool) *controllerServer {
+	if ephemeral {
+		return &controllerServer{caps: getControllerServiceCapabilities(nil)}
+	}
 	return &controllerServer{
 		caps: getControllerServiceCapabilities(
 			[]csi.ControllerServiceCapability_RPC_Type{
@@ -95,8 +97,7 @@ func (cs *controllerServer) CreateVolume(ctx context.Context, req *csi.CreateVol
 		return nil, status.Errorf(codes.OutOfRange, "Requested capacity %d exceeds maximum allowed %d", capacity, maxStorageCapacity)
 	}
 	volumeID := uuid.NewUUID().String()
-	path := provisionRoot + volumeID
-	err := os.MkdirAll(path, 0777)
+	path, err := createVolumeDir(volumeID)
 	if err != nil {
 		glog.V(3).Infof("failed to create volume: %v", err)
 		return nil, err
@@ -150,8 +151,7 @@ func (cs *controllerServer) DeleteVolume(ctx context.Context, req *csi.DeleteVol
 	}
 	volumeID := req.VolumeId
 	glog.V(4).Infof("deleting volume %s", volumeID)
-	path := provisionRoot + volumeID
-	os.RemoveAll(path)
+	deleteVolumeDir(volumeID)
 	delete(hostPathVolumes, volumeID)
 	return &csi.DeleteVolumeResponse{}, nil
 }

pkg/hostpath/hostpath.go

@@ -18,6 +18,7 @@ package hostpath
 
 import (
 	"fmt"
+	"os"
 
 	"github.com/golang/glog"
 
@@ -33,6 +34,10 @@ const (
 	tib100 int64 = tib * 100
 )
 
+const (
+	volumeRoot = "/tmp"
+)
+
 type hostPath struct {
 	name      string
 	nodeID    string
@@ -102,13 +107,10 @@ func NewHostPathDriver(driverName, nodeID, endpoint string, ephemeral bool) (*ho
 func (hp *hostPath) Run() {
 	s := NewNonBlockingGRPCServer()
 
-	hp.ids = nil
-	hp.cs = nil
+	hp.ids = NewIdentityServer(hp.name, hp.version)
 	hp.ns = NewNodeServer(hp.nodeID, hp.ephemeral)
-	if !hp.ephemeral {
-		hp.ids = NewIdentityServer(hp.name, hp.version)
-		hp.cs = NewControllerServer()
-	}
+	hp.cs = NewControllerServer(hp.ephemeral)
+
 	s.Start(hp.endpoint, hp.ids, hp.cs, hp.ns)
 	s.Wait()
 }
@@ -137,3 +139,29 @@ func getSnapshotByName(name string) (hostPathSnapshot, error) {
 	}
 	return hostPathSnapshot{}, fmt.Errorf("snapshot name %s does not exit in the snapshots list", name)
 }
+
+// getVolumePath returs the canonical path for hostpath volume
+func getVolumePath(volID string) string {
+	return fmt.Sprintf("%s/%s", volumeRoot, volID)
+}
+
+// createVolume create the directory for the hostpath volume.
+// It returns the volume path or err if one occurs.
+func createVolumeDir(volID string) (string, error) {
+	path := getVolumePath(volID)
+	err := os.MkdirAll(path, 0777)
+	if err != nil {
+		return "", err
+	}
+
+	return path, nil
+}
+
+// deleteVolume deletes the directory for the hostpath volume.
+func deleteVolumeDir(volID string) error {
+	path := getVolumePath(volID)
+	if err := os.RemoveAll(path); err != nil {
+		return err
+	}
+	return nil
+}

pkg/hostpath/nodeserver.go

@@ -17,7 +17,9 @@ limitations under the License.
 package hostpath
 
 import (
+	"fmt"
 	"os"
+	"strings"
 
 	"github.com/golang/glog"
 	"golang.org/x/net/context"
@@ -90,19 +92,25 @@ func (ns *nodeServer) NodePublishVolume(ctx context.Context, req *csi.NodePublis
 		options = append(options, "ro")
 	}
 	mounter := mount.New("")
-	path := provisionRoot + volumeId
-	newEphemeral := false
+
+	path := getVolumePath(volumeId)
 	if ns.ephemeral {
-		if err = os.MkdirAll(path, 0777); err != nil && !os.IsNotExist(err) {
+		volPath, err := createVolumeDir(volumeId)
+		if err != nil && !os.IsExist(err) {
 			return nil, status.Error(codes.Internal, err.Error())
 		}
-		newEphemeral = true
+		glog.V(4).Infof("ephemeral mode: created volume: %s", volPath)
 	}
+
 	if err := mounter.Mount(path, targetPath, "", options); err != nil {
-		if newEphemeral {
-			os.RemoveAll(path)
+		var errList strings.Builder
+		errList.WriteString(err.Error())
+		if ns.ephemeral {
+			if rmErr := os.RemoveAll(path); rmErr != nil && !os.IsNotExist(rmErr) {
+				errList.WriteString(fmt.Sprintf(" :%s", rmErr.Error()))
+			}
 		}
-		return nil, err
+		return nil, status.Error(codes.Internal, errList.String())
 	}
 
 	return &csi.NodePublishVolumeResponse{}, nil
@@ -129,8 +137,7 @@ func (ns *nodeServer) NodeUnpublishVolume(ctx context.Context, req *csi.NodeUnpu
 
 	if ns.ephemeral {
 		glog.V(4).Infof("deleting volume %s", volumeID)
-		path := provisionRoot + volumeID
-		os.RemoveAll(path)
+		deleteVolumeDir(volumeID)
 	}
 
 	return &csi.NodeUnpublishVolumeResponse{}, nil