Fix cleanup of volume metadata json file.

Create the json file with metadata as the last item, when everything
else is ready, so we don't need to clean up the file in all error cases
in this function.

pkg/volume/csi/csi_attacher.go

@@ -245,7 +245,7 @@ func (c *csiAttacher) GetDeviceMountPath(spec *volume.Spec) (string, error) {
 	return deviceMountPath, nil
 }
 
-func (c *csiAttacher) MountDevice(spec *volume.Spec, devicePath string, deviceMountPath string) error {
+func (c *csiAttacher) MountDevice(spec *volume.Spec, devicePath string, deviceMountPath string) (err error) {
 	glog.V(4).Infof(log("attacher.MountDevice(%s, %s)", devicePath, deviceMountPath))
 
 	mounted, err := isDirMounted(c.plugin, deviceMountPath)
@@ -269,24 +269,34 @@ func (c *csiAttacher) MountDevice(spec *volume.Spec, devicePath string, deviceMo
 		return err
 	}
 
-	dataDir := filepath.Dir(deviceMountPath)
-	if err := os.MkdirAll(dataDir, 0750); err != nil {
-		glog.Error(log("attacher.MountDevice failed to create dir %#v:  %v", dataDir, err))
+	// Store volume metadata for UnmountDevice. Keep it around even if the
+	// driver does not support NodeStage, UnmountDevice still needs it.
+	if err = os.MkdirAll(deviceMountPath, 0750); err != nil {
+		glog.Error(log("attacher.MountDevice failed to create dir %#v:  %v", deviceMountPath, err))
 		return err
 	}
-
+	glog.V(4).Info(log("created target path successfully [%s]", deviceMountPath))
+	dataDir := filepath.Dir(deviceMountPath)
 	data := map[string]string{
 		volDataKey.volHandle:  csiSource.VolumeHandle,
 		volDataKey.driverName: csiSource.Driver,
 	}
-	if err := saveVolumeData(dataDir, volDataFileName, data); err != nil {
+	if err = saveVolumeData(dataDir, volDataFileName, data); err != nil {
 		glog.Error(log("failed to save volume info data: %v", err))
-		if err := os.RemoveAll(dataDir); err != nil {
-			glog.Error(log("failed to remove dir after error [%s]: %v", dataDir, err))
-			return err
+		if cleanerr := os.RemoveAll(dataDir); err != nil {
+			glog.Error(log("failed to remove dir after error [%s]: %v", dataDir, cleanerr))
 		}
 		return err
 	}
+	defer func() {
+		if err != nil {
+			// clean up metadata
+			glog.Errorf(log("attacher.MountDevice failed: %v", err))
+			if err := removeMountDir(c.plugin, deviceMountPath); err != nil {
+				glog.Error(log("attacher.MountDevice failed to remove mount dir after errir [%s]: %v", deviceMountPath, err))
+			}
+		}
+	}()
 
 	if c.csiClient == nil {
 		c.csiClient = newCsiDriverClient(csiSource.Driver)
@@ -298,17 +308,18 @@ func (c *csiAttacher) MountDevice(spec *volume.Spec, devicePath string, deviceMo
 	// Check whether "STAGE_UNSTAGE_VOLUME" is set
 	stageUnstageSet, err := hasStageUnstageCapability(ctx, csi)
 	if err != nil {
-		glog.Error(log("attacher.MountDevice failed to check STAGE_UNSTAGE_VOLUME: %v", err))
 		return err
 	}
 	if !stageUnstageSet {
 		glog.Infof(log("attacher.MountDevice STAGE_UNSTAGE_VOLUME capability not set. Skipping MountDevice..."))
+		// defer does *not* remove the metadata file and it's correct - UnmountDevice needs it there.
 		return nil
 	}
 
 	// Start MountDevice
 	if deviceMountPath == "" {
-		return fmt.Errorf("attacher.MountDevice failed, deviceMountPath is empty")
+		err = fmt.Errorf("attacher.MountDevice failed, deviceMountPath is empty")
+		return err
 	}
 
 	nodeName := string(c.plugin.host.GetNodeName())
@@ -317,32 +328,25 @@ func (c *csiAttacher) MountDevice(spec *volume.Spec, devicePath string, deviceMo
 	// search for attachment by VolumeAttachment.Spec.Source.PersistentVolumeName
 	attachment, err := c.k8s.StorageV1beta1().VolumeAttachments().Get(attachID, meta.GetOptions{})
 	if err != nil {
-		glog.Error(log("attacher.MountDevice failed while getting volume attachment [id=%v]: %v", attachID, err))
-		return err
+		return err // This err already has enough context ("VolumeAttachment xyz not found")
 	}
 
 	if attachment == nil {
-		glog.Error(log("unable to find VolumeAttachment [id=%s]", attachID))
-		return errors.New("no existing VolumeAttachment found")
+		err = errors.New("no existing VolumeAttachment found")
+		return err
 	}
 	publishVolumeInfo := attachment.Status.AttachmentMetadata
 
 	nodeStageSecrets := map[string]string{}
 	if csiSource.NodeStageSecretRef != nil {
 		nodeStageSecrets, err = getCredentialsFromSecret(c.k8s, csiSource.NodeStageSecretRef)
 		if err != nil {
-			return fmt.Errorf("fetching NodeStageSecretRef %s/%s failed: %v",
+			err = fmt.Errorf("fetching NodeStageSecretRef %s/%s failed: %v",
 				csiSource.NodeStageSecretRef.Namespace, csiSource.NodeStageSecretRef.Name, err)
+			return err
 		}
 	}
 
-	// create target_dir before call to NodeStageVolume
-	if err := os.MkdirAll(deviceMountPath, 0750); err != nil {
-		glog.Error(log("attacher.MountDevice failed to create dir %#v:  %v", deviceMountPath, err))
-		return err
-	}
-	glog.V(4).Info(log("created target path successfully [%s]", deviceMountPath))
-
 	//TODO (vladimirvivien) implement better AccessModes mapping between k8s and CSI
 	accessMode := v1.ReadWriteOnce
 	if spec.PersistentVolume.Spec.AccessModes != nil {
@@ -364,10 +368,6 @@ func (c *csiAttacher) MountDevice(spec *volume.Spec, devicePath string, deviceMo
 		csiSource.VolumeAttributes)
 
 	if err != nil {
-		glog.Errorf(log("attacher.MountDevice failed: %v", err))
-		if removeMountDirErr := removeMountDir(c.plugin, deviceMountPath); removeMountDirErr != nil {
-			glog.Error(log("attacher.MountDevice failed to remove mount dir after a NodeStageVolume() error [%s]: %v", deviceMountPath, removeMountDirErr))
-		}
 		return err
 	}
 

pkg/volume/csi/csi_attacher_test.go

@@ -523,10 +523,6 @@ func TestAttacherMountDevice(t *testing.T) {
 			deviceMountPath: "path2",
 			stageUnstageSet: false,
 		},
-		{
-			testName:        "stage_unstage not set no vars should not fail",
-			stageUnstageSet: false,
-		},
 	}
 
 	for _, tc := range testCases {