Invoke helper Pod on resize

Update the resize function to invoke the helper Pod with the "resize"
script.

This also adds some dummy resize scripts, which store the resize data in
a file in the PV. It does not add though any sample script for the XFS
quota resize.

Signed-off-by: Marjus Cako <marios.cako@gmail.com>

Author: marjuscako

debug/config.yaml

@@ -74,6 +74,27 @@ data:
         done
 
         rm -rf ${absolutePath}
+  resize: |-
+        #!/bin/sh
+        while getopts "m:s:p:" opt
+        do
+            case $opt in
+                p)
+                absolutePath=$OPTARG
+                ;;
+                s)
+                sizeInBytes=$OPTARG
+                ;;
+                m)
+                volMode=$OPTARG
+                ;;
+            esac
+        done
+
+        echo "VOL_DIR: $VOL_DIR" > "$VOL_DIR/.resizerdata"
+        echo "VOL_MODE: $VOL_MODE" >> "$VOL_DIR/.resizerdata"
+        echo "VOL_SIZE_BYTES: $VOL_SIZE_BYTES" >> "$VOL_DIR/.resizerdata"
+
   helperPod.yaml: |-
         apiVersion: v1
         kind: Pod

deploy/example-config.yaml

@@ -29,6 +29,10 @@ data:
     #!/bin/sh
     set -eu
     rm -rf "$VOL_DIR"
+  resize: |-
+    echo "VOL_DIR: $VOL_DIR" > "$VOL_DIR/.resizerdata"
+    echo "VOL_MODE: $VOL_MODE" >> "$VOL_DIR/.resizerdata"
+    echo "VOL_SIZE_BYTES: $VOL_SIZE_BYTES" >> "$VOL_DIR/.resizerdata"
   helperPod.yaml: |-
     apiVersion: v1
     kind: Pod

deploy/local-path-storage.yaml

@@ -145,6 +145,10 @@ data:
     #!/bin/sh
     set -eu
     rm -rf "$VOL_DIR"
+  resize: |-
+    echo "VOL_DIR: $VOL_DIR" > "$VOL_DIR/.resizerdata"
+    echo "VOL_MODE: $VOL_MODE" >> "$VOL_DIR/.resizerdata"
+    echo "VOL_SIZE_BYTES: $VOL_SIZE_BYTES" >> "$VOL_DIR/.resizerdata"
   helperPod.yaml: |-
     apiVersion: v1
     kind: Pod

main.go

@@ -180,7 +180,7 @@ func findConfigFileFromConfigMap(kubeClient clientset.Interface, namespace, conf
 	}
 	value, ok := cm.Data[key]
 	if !ok {
-		return "", fmt.Errorf("%v is not exist in local-path-config ConfigMap", key)
+		return "", fmt.Errorf("%v does not exist in local-path-config ConfigMap", key)
 	}
 	return value, nil
 }
@@ -279,7 +279,7 @@ func startDaemon(c *cli.Context) error {
 		pvController.VolumesInformer(volumeInformer),
 	)
 
-	resizer := NewResizer()
+	resizer := NewResizer(provisioner)
 	rc := resizeController.NewResizeController(
 		LocalPathResizerName,
 		resizer,

provisioner.go

@@ -87,6 +87,7 @@ type ConfigData struct {
 	SharedFileSystemPath string             `json:"sharedFileSystemPath,omitempty"`
 	SetupCommand         string             `json:"setupCommand,omitempty"`
 	TeardownCommand      string             `json:"teardownCommand,omitempty"`
+	ResizeCommand        string             `json:"resizeCommand,omitempty"`
 }
 
 type NodePathMap struct {
@@ -99,6 +100,7 @@ type Config struct {
 	SharedFileSystemPath string
 	SetupCommand         string
 	TeardownCommand      string
+	ResizeCommand        string
 }
 
 func NewProvisioner(ctx context.Context, kubeClient *clientset.Clientset,
@@ -526,6 +528,13 @@ func (p *LocalPathProvisioner) createHelperPod(action ActionType, cmd []string,
 		})
 	}
 
+	if p.config.ResizeCommand == "" {
+		keyToPathItems = append(keyToPathItems, v1.KeyToPath{
+			Key:  "resize",
+			Path: "resize",
+		})
+	}
+
 	if len(keyToPathItems) > 0 {
 		lpvVolumes = append(lpvVolumes, v1.Volume{
 			Name: "script",
@@ -674,6 +683,7 @@ func canonicalizeConfig(data *ConfigData) (cfg *Config, err error) {
 	cfg.SharedFileSystemPath = data.SharedFileSystemPath
 	cfg.SetupCommand = data.SetupCommand
 	cfg.TeardownCommand = data.TeardownCommand
+	cfg.ResizeCommand = data.ResizeCommand
 	cfg.NodePathMap = map[string]*NodePathMap{}
 	for _, n := range data.NodePathMap {
 		if cfg.NodePathMap[n.Node] != nil {

resizer.go

@@ -1,14 +1,19 @@
 package main
 
 import (
+	"github.com/Sirupsen/logrus"
 	v1 "k8s.io/api/core/v1"
 	"k8s.io/apimachinery/pkg/api/resource"
 )
 
-const LocalPathResizerName = "LocalPathResizer"
+const (
+	LocalPathResizerName = "LocalPathResizer"
+	ActionTypeResize     = "resize"
+)
 
 type LocalPathResizer struct {
-	name string
+	name        string
+	provisioner *LocalPathProvisioner
 }
 
 func (r *LocalPathResizer) Name() string {
@@ -24,12 +29,44 @@ func (r *LocalPathResizer) CanSupport(pv *v1.PersistentVolume, pvc *v1.Persisten
 }
 
 func (r *LocalPathResizer) Resize(pv *v1.PersistentVolume, requestSize resource.Quantity) (newSize resource.Quantity, fsResizeRequired bool, err error) {
+
+	logrus.Debugf("Resize reconciler for pv %q with request size %q", pv.Name, requestSize.String())
+	path, node, err := r.provisioner.getPathAndNodeForPV(pv)
+	if err != nil {
+		logrus.Errorf("failed to get path and node: %v", err)
+		return requestSize, false, err
+	}
+
+	if node == "" {
+		logrus.Infof("Resizing volume %v at %v", pv.Name, path)
+	} else {
+		logrus.Infof("Resizing volume %v at %v:%v", pv.Name, node, path)
+	}
+
+	resizeCmd := make([]string, 0, 2)
+	if r.provisioner.config.ResizeCommand == "" {
+		resizeCmd = append(resizeCmd, "/bin/sh", "/script/resize")
+	} else {
+		resizeCmd = append(resizeCmd, r.provisioner.config.ResizeCommand)
+	}
+
+	if err := r.provisioner.createHelperPod(ActionTypeResize, resizeCmd, volumeOptions{
+		Name:        pv.Name,
+		Path:        path,
+		Mode:        *pv.Spec.VolumeMode,
+		SizeInBytes: requestSize.Value(),
+		Node:        node,
+	}); err != nil {
+		return requestSize, false, err
+	}
+
 	return requestSize, false, nil
 }
 
-func NewResizer() *LocalPathResizer {
+func NewResizer(p *LocalPathProvisioner) *LocalPathResizer {
 	r := &LocalPathResizer{
-		name: LocalPathResizerName,
+		name:        LocalPathResizerName,
+		provisioner: p,
 	}
 	return r
 }