add expand volume controller

Signed-off-by: Xin Wang <wileywang@yunify.com>

cmd/controller-manager/app/controllers.go

@@ -25,8 +25,8 @@ import (
 	"kubesphere.io/kubesphere/pkg/controller/destinationrule"
 	"kubesphere.io/kubesphere/pkg/controller/job"
 	"kubesphere.io/kubesphere/pkg/controller/s2ibinary"
-
 	"kubesphere.io/kubesphere/pkg/controller/s2irun"
+	"kubesphere.io/kubesphere/pkg/controller/storage/expansion"
 
 	//"kubesphere.io/kubesphere/pkg/controller/job"
 	"kubesphere.io/kubesphere/pkg/controller/virtualservice"
@@ -118,6 +118,15 @@ func AddControllers(mgr manager.Manager, cfg *rest.Config, stopCh <-chan struct{
 		kubesphereInformer.Devops().V1alpha1().S2iBinaries(),
 		s2iInformer.Devops().V1alpha1().S2iRuns())
 
+	volumeExpansionController := expansion.NewVolumeExpansionController(
+		kubeClient,
+		informerFactory.Core().V1().PersistentVolumeClaims(),
+		informerFactory.Storage().V1().StorageClasses(),
+		informerFactory.Core().V1().Pods(),
+		informerFactory.Apps().V1().Deployments(),
+		informerFactory.Apps().V1().ReplicaSets(),
+		informerFactory.Apps().V1().StatefulSets())
+
 	kubesphereInformer.Start(stopCh)
 	istioInformer.Start(stopCh)
 	informerFactory.Start(stopCh)
@@ -131,6 +140,7 @@ func AddControllers(mgr manager.Manager, cfg *rest.Config, stopCh <-chan struct{
 		"job-controller":             jobController,
 		"s2ibinary-controller":       s2iBinaryController,
 		"s2irun-controller":          s2iRunController,
+		"volumeexpansion-controller": volumeExpansionController,
 	}
 
 	for name, ctrl := range controllers {

pkg/controller/storage/expansion/expansion_controller.go

@@ -0,0 +1,505 @@
+/*
+
+ Copyright 2019 The KubeSphere Authors.
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+
+*/
+
+package expansion
+
+import (
+	"errors"
+	"fmt"
+	appsv1 "k8s.io/api/apps/v1"
+	autoscalingv1 "k8s.io/api/autoscaling/v1"
+	corev1 "k8s.io/api/core/v1"
+	storagev1 "k8s.io/api/storage/v1"
+	apierrors "k8s.io/apimachinery/pkg/api/errors"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/labels"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	utilruntime "k8s.io/apimachinery/pkg/util/runtime"
+	"k8s.io/apimachinery/pkg/util/wait"
+	appsv1informers "k8s.io/client-go/informers/apps/v1"
+	corev1informers "k8s.io/client-go/informers/core/v1"
+	storagev1informer "k8s.io/client-go/informers/storage/v1"
+	"k8s.io/client-go/kubernetes"
+	"k8s.io/client-go/kubernetes/scheme"
+	typedcorev1 "k8s.io/client-go/kubernetes/typed/core/v1"
+	listerappsv1 "k8s.io/client-go/listers/apps/v1"
+	listercorev1 "k8s.io/client-go/listers/core/v1"
+	listerstoragev1 "k8s.io/client-go/listers/storage/v1"
+	"k8s.io/client-go/tools/cache"
+	"k8s.io/client-go/tools/record"
+	"k8s.io/client-go/util/retry"
+	"k8s.io/client-go/util/workqueue"
+	"k8s.io/klog"
+	"time"
+)
+
+const controllerAgentName = "expansion-controller"
+
+var supportedProvisioner = []string{"disk.csi.qingcloud.com", "csi-qingcloud"}
+
+var retryTime = wait.Backoff{
+	Duration: 1 * time.Second,
+	Factor:   2,
+	Steps:    12,
+}
+
+type VolumeExpansionController struct {
+	kubeclientset kubernetes.Interface
+	pvcLister     listercorev1.PersistentVolumeClaimLister
+	pvcSynced     cache.InformerSynced
+	classLister   listerstoragev1.StorageClassLister
+	classSynced   cache.InformerSynced
+	podLister     listercorev1.PodLister
+	podSynced     cache.InformerSynced
+	deployLister  listerappsv1.DeploymentLister
+	deploySynced  cache.InformerSynced
+	rsLister      listerappsv1.ReplicaSetLister
+	rsSynced      cache.InformerSynced
+	stsLister     listerappsv1.StatefulSetLister
+	stsSynced     cache.InformerSynced
+	workqueue     workqueue.RateLimitingInterface
+	recorder      record.EventRecorder
+}
+
+// NewController returns a new volume expansion controller
+func NewVolumeExpansionController(
+	kubeclientset kubernetes.Interface,
+	pvcInformer corev1informers.PersistentVolumeClaimInformer,
+	classInformer storagev1informer.StorageClassInformer,
+	podInformer corev1informers.PodInformer,
+	deployInformer appsv1informers.DeploymentInformer,
+	rsInformer appsv1informers.ReplicaSetInformer,
+	stsInformer appsv1informers.StatefulSetInformer) *VolumeExpansionController {
+	klog.V(4).Info("Creating event broadcaster")
+	eventBroadcaster := record.NewBroadcaster()
+	eventBroadcaster.StartLogging(klog.Infof)
+	eventBroadcaster.StartRecordingToSink(&typedcorev1.EventSinkImpl{Interface: kubeclientset.CoreV1().Events("")})
+	recorder := eventBroadcaster.NewRecorder(scheme.Scheme, corev1.EventSource{Component: controllerAgentName})
+	controller := &VolumeExpansionController{
+		kubeclientset: kubeclientset,
+		pvcLister:     pvcInformer.Lister(),
+		pvcSynced:     pvcInformer.Informer().HasSynced,
+		classLister:   classInformer.Lister(),
+		classSynced:   classInformer.Informer().HasSynced,
+		podLister:     podInformer.Lister(),
+		podSynced:     podInformer.Informer().HasSynced,
+		deployLister:  deployInformer.Lister(),
+		deploySynced:  deployInformer.Informer().HasSynced,
+		rsLister:      rsInformer.Lister(),
+		rsSynced:      rsInformer.Informer().HasSynced,
+		stsLister:     stsInformer.Lister(),
+		stsSynced:     stsInformer.Informer().HasSynced,
+		workqueue:     workqueue.NewNamedRateLimitingQueue(workqueue.DefaultControllerRateLimiter(), "expansion"),
+		recorder:      recorder,
+	}
+	klog.V(2).Info("Setting up event handlers")
+	pvcInformer.Informer().AddEventHandler(cache.ResourceEventHandlerFuncs{
+		AddFunc: controller.enqueuePVC,
+		UpdateFunc: func(old, new interface{}) {
+			oldPVC, ok := old.(*corev1.PersistentVolumeClaim)
+			if !ok {
+				return
+			}
+			oldSize := oldPVC.Spec.Resources.Requests[corev1.ResourceStorage]
+			newPVC, ok := new.(*corev1.PersistentVolumeClaim)
+			if !ok {
+				return
+			}
+			newSize := newPVC.Spec.Resources.Requests[corev1.ResourceStorage]
+			if newSize.Cmp(oldSize) > 0 && newSize.Cmp(newPVC.Status.Capacity[corev1.ResourceStorage]) > 0 {
+				controller.handleObject(new)
+			}
+		},
+		DeleteFunc: controller.enqueuePVC,
+	})
+	return controller
+}
+
+func (c *VolumeExpansionController) Start(stopCh <-chan struct{}) error {
+	return c.Run(5, stopCh)
+}
+
+func (c *VolumeExpansionController) Run(threadiness int, stopCh <-chan struct{}) error {
+	defer utilruntime.HandleCrash()
+	defer c.workqueue.ShutDown()
+	klog.V(2).Info("Starting expand volume controller")
+	klog.V(2).Info("Waiting for informer caches to sync")
+	if ok := cache.WaitForCacheSync(stopCh, c.pvcSynced, c.classSynced, c.podSynced, c.deploySynced, c.rsSynced,
+		c.stsSynced); !ok {
+		return fmt.Errorf("failed to wait for caches to sync")
+	}
+
+	klog.V(2).Info("Starting workers")
+	for i := 0; i < threadiness; i++ {
+		go wait.Until(c.runWorker, time.Second, stopCh)
+	}
+
+	klog.V(2).Info("Started workers")
+	<-stopCh
+	klog.V(2).Info("Shutting down workers")
+
+	return nil
+}
+
+func (c *VolumeExpansionController) runWorker() {
+	for c.processNextWorkItem() {
+	}
+}
+
+func (c *VolumeExpansionController) processNextWorkItem() bool {
+	obj, shutdown := c.workqueue.Get()
+
+	if shutdown {
+		return false
+	}
+
+	err := func(obj interface{}) error {
+		defer c.workqueue.Done(obj)
+		var key string
+		var ok bool
+
+		if key, ok = obj.(string); !ok {
+			c.workqueue.Forget(obj)
+			utilruntime.HandleError(fmt.Errorf("expected string in workqueue but got %#v", obj))
+			return nil
+		}
+		if err := c.syncHandler(key); err != nil {
+			c.workqueue.AddRateLimited(key)
+			return fmt.Errorf("error syncing '%s': %s, requeuing", key, err.Error())
+		}
+		c.workqueue.Forget(obj)
+		klog.V(2).Infof("Successfully synced '%s'", key)
+		return nil
+	}(obj)
+
+	if err != nil {
+		utilruntime.HandleError(err)
+		return true
+	}
+
+	return true
+}
+
+// syncHandler will re-attach PVC on workloads.
+// Step 1. Find the workload (deployment or statefulset) mounting PVC.
+// If more than one workloads mounts the same PVC, the controller will not
+// do anything.
+// Step 2. Verify workload types.
+// Step 3. Scale down workload.
+// Step 4. Retry to check PVC status.
+// Step 5. Scale up workload.
+func (c *VolumeExpansionController) syncHandler(key string) error {
+	klog.V(5).Infof("syncHandler: handle %s", key)
+	namespace, name, err := cache.SplitMetaNamespaceKey(key)
+	if err != nil {
+		utilruntime.HandleError(fmt.Errorf("invalid resource key: %s", key))
+		return nil
+	}
+
+	// Get PVC source
+	pvc, err := c.pvcLister.PersistentVolumeClaims(namespace).Get(name)
+	if err != nil {
+		// The PVC resource may no longer exist, in which case we stop processing.
+		if apierrors.IsNotFound(err) {
+			klog.V(4).Infof("PVC '%s' in work queue no longer exists", key)
+			utilruntime.HandleError(fmt.Errorf("PVC '%s' in work queue no longer exists", key))
+			return nil
+		}
+		return err
+	}
+	// find workload
+	workload, err := c.findWorkload(name, namespace)
+	if err != nil {
+		return err
+	}
+	if workload == nil {
+		klog.V(4).Infof("Cannot find any Pods mounting PVC %s", key)
+		return nil
+	}
+	klog.V(5).Infof("Find workload %T pvc name %s", workload, pvc.GetName())
+	// handle supported workload
+	switch workload.(type) {
+	case *appsv1.StatefulSet:
+		sts := workload.(*appsv1.StatefulSet)
+		klog.V(5).Infof("Find StatefulSet %s", sts.GetName())
+	case *appsv1.Deployment:
+		deploy := workload.(*appsv1.Deployment)
+		klog.V(5).Infof("Find Deployment %s", deploy.GetName())
+	default:
+		klog.Errorf("Unsupported workload type %T", workload)
+		return nil
+	}
+	// Scale workload to 0
+	if err = c.scaleDown(workload, pvc.GetNamespace()); err != nil {
+		klog.V(2).Infof("scale down PVC %s mounted workloads failed %s", key, err.Error())
+		return err
+	}
+	klog.V(2).Infof("Scale down PVC %s mounted workloads succeed", key)
+	// Wait to scale up
+	err = retry.RetryOnConflict(retryTime, func() error {
+		klog.V(4).Info("waiting for PVC filesystem expansion")
+		if !c.isWaitingScaleUp(name, namespace) {
+			return apierrors.NewConflict(schema.GroupResource{Resource: "PersistentVolumeClaim"}, key,
+				errors.New("waiting for scaling down and expanding disk"))
+		}
+		return nil
+	})
+	klog.V(5).Info("after waiting")
+	if err != nil {
+		klog.Errorf("Waiting timeout, error: %s", err.Error())
+	}
+
+	// Scale up
+	if err = c.scaleUp(workload, namespace); err != nil {
+		klog.V(2).Infof("Scale up PVC %s mounted workloads failed %s", key, err.Error())
+		return err
+	}
+	klog.V(2).Infof("Scale up PVC %s mounted workloads succeed", key)
+	return nil
+}
+
+// handleObject will take any resource implementing metav1.Object and attempt
+// to find the PVC resource that 'owns' it. It does this by looking at the
+// StorageClass of PVC whether supporting provisioner and allowing volume
+// expansion.
+// In KS 2.1, the controller only supports disk.csi.qingcloud.com and
+// csi-qingcloud as storageclass provisioner.
+func (c *VolumeExpansionController) handleObject(obj interface{}) {
+	var object metav1.Object
+	var ok bool
+	if object, ok = obj.(metav1.Object); !ok {
+		tombstone, ok := obj.(cache.DeletedFinalStateUnknown)
+		if !ok {
+			utilruntime.HandleError(fmt.Errorf("error decoding object, invalid type"))
+			return
+		}
+		object, ok = tombstone.Obj.(metav1.Object)
+		if !ok {
+			utilruntime.HandleError(fmt.Errorf("error decoding object tombstone, invalid type"))
+			return
+		}
+		klog.V(4).Infof("Recovered deleted object '%s' from tombstone", object.GetName())
+	}
+	klog.V(4).Infof("Processing object: %s", object.GetName())
+
+	pvc := obj.(*corev1.PersistentVolumeClaim)
+	// Check storage class
+	// In KS 2.1, we only support disk.csi.qingcloud.com as storageclass provisioner.
+	class := c.getStorageClass(pvc)
+	klog.V(4).Infof("Get PVC %s SC was %s", pvc.String(), class.String())
+	if class == nil {
+		return
+	}
+	if *class.AllowVolumeExpansion == false {
+		return
+	}
+	for _, p := range supportedProvisioner {
+		if class.Provisioner == p {
+			klog.V(5).Infof("enqueue PVC %s", claimToClaimKey(pvc))
+			c.enqueuePVC(obj)
+			return
+		}
+	}
+}
+
+func (c *VolumeExpansionController) getStorageClass(pvc *corev1.PersistentVolumeClaim) *storagev1.StorageClass {
+	if pvc == nil {
+		return nil
+	}
+	claimClass := getPersistentVolumeClaimClass(pvc)
+	if claimClass == "" {
+		klog.V(4).Infof("volume expansion is disabled for PVC without StorageClasses: %s",
+			claimToClaimKey(pvc))
+		return nil
+	}
+	class, err := c.classLister.Get(claimClass)
+	if err != nil {
+		klog.V(4).Infof("failed to expand PVC: %s with error: %v", claimToClaimKey(pvc), err)
+		return nil
+	}
+	return class
+}
+
+// enqueuePVC takes a PVC resource and converts it into a namespace/name
+// string which is then put onto the work queue. This method should *not* be
+// passed resources of any type other than PVC.
+func (c *VolumeExpansionController) enqueuePVC(obj interface{}) {
+	pvc, ok := obj.(*corev1.PersistentVolumeClaim)
+	if !ok {
+		return
+	}
+	size := pvc.Spec.Resources.Requests[corev1.ResourceStorage]
+	statusSize := pvc.Status.Capacity[corev1.ResourceStorage]
+
+	if pvc.Status.Phase == corev1.ClaimBound && size.Cmp(statusSize) > 0 {
+		key, err := cache.DeletionHandlingMetaNamespaceKeyFunc(pvc)
+		if err != nil {
+			utilruntime.HandleError(fmt.Errorf("couldn't get key for object %#v: %v", pvc, err))
+			return
+		}
+		c.workqueue.Add(key)
+	}
+}
+
+// findWorkload returns the pointer of Pod, StatefulSet or Deployment mounting the PVC.
+func (c *VolumeExpansionController) findWorkload(pvc, namespace string) (workloadPtr interface{}, err error) {
+	podList, err := c.podLister.Pods(namespace).List(labels.Everything())
+	klog.V(4).Infof("podlist len %d", len(podList))
+	if err != nil {
+		return nil, err
+	}
+	// Which pod mounting PVC
+	podPtrListMountPVC := getPodMountPVC(podList, pvc)
+	klog.V(4).Infof("Get %d pods mounting PVC", len(podPtrListMountPVC))
+	// In KS 2.1, automatic re-attach PVC only support PVC mounted on a single Pod.
+	if len(podPtrListMountPVC) != 1 {
+		return nil, nil
+	}
+	// If pod managed by Deployment, StatefulSet, it returns Deployment or StatefulSet.
+	// If not, it returns Pod.
+	klog.V(4).Info("Find pod parent")
+	ownerRef, err := c.findPodParent(podPtrListMountPVC[0])
+	if err != nil {
+		return nil, err
+	}
+	if ownerRef == nil {
+		// a single pod
+		return podPtrListMountPVC[0], nil
+	} else {
+		klog.V(4).Infof("OwnerRef kind %s", ownerRef.Kind)
+		switch ownerRef.Kind {
+		case "StatefulSet":
+			return c.stsLister.StatefulSets(namespace).Get(ownerRef.Name)
+		case "Deployment":
+			return c.deployLister.Deployments(namespace).Get(ownerRef.Name)
+		default:
+			return nil, nil
+		}
+	}
+
+}
+
+// If the Pod don't controlled by any controller, return nil.
+func (c *VolumeExpansionController) findPodParent(pod *corev1.Pod) (*metav1.OwnerReference, error) {
+	if pod == nil {
+		return nil, nil
+	}
+	if ownerRef := metav1.GetControllerOf(pod); ownerRef != nil {
+		switch ownerRef.Kind {
+		case "ReplicaSet":
+			// get deploy
+			rs, err := c.rsLister.ReplicaSets(pod.GetNamespace()).Get(ownerRef.Name)
+			if err != nil {
+				return nil, err
+			}
+			if rsOwnerRef := metav1.GetControllerOf(rs); rsOwnerRef != nil {
+				return rsOwnerRef, nil
+			} else {
+				return ownerRef, nil
+			}
+		case "StatefulSet":
+			return ownerRef, nil
+		default:
+			return &metav1.OwnerReference{}, nil
+		}
+	}
+	return nil, nil
+}
+
+func (c *VolumeExpansionController) scaleDown(workload interface{}, namespace string) error {
+	switch workload.(type) {
+	case *appsv1.Deployment:
+		deploy := workload.(*appsv1.Deployment)
+		scale := &autoscalingv1.Scale{
+			ObjectMeta: metav1.ObjectMeta{
+				Name:      deploy.GetName(),
+				Namespace: deploy.GetNamespace(),
+			},
+			Spec: autoscalingv1.ScaleSpec{
+				Replicas: 0,
+			},
+		}
+		_, err := c.kubeclientset.AppsV1().Deployments(namespace).UpdateScale(deploy.GetName(), scale)
+		return err
+	case *appsv1.StatefulSet:
+		sts := workload.(*appsv1.StatefulSet)
+		scale := &autoscalingv1.Scale{
+			ObjectMeta: metav1.ObjectMeta{
+				Name:      sts.GetName(),
+				Namespace: sts.GetNamespace(),
+			},
+			Spec: autoscalingv1.ScaleSpec{
+				Replicas: 0,
+			},
+		}
+		_, err := c.kubeclientset.AppsV1().StatefulSets(namespace).UpdateScale(sts.GetName(), scale)
+		return err
+	default:
+		return fmt.Errorf("unsupported type %T", workload)
+	}
+}
+
+func (c *VolumeExpansionController) scaleUp(workload interface{}, namespace string) error {
+	switch workload.(type) {
+	case *appsv1.Deployment:
+		deploy := workload.(*appsv1.Deployment)
+		scale := &autoscalingv1.Scale{
+			ObjectMeta: metav1.ObjectMeta{
+				Name:      deploy.GetName(),
+				Namespace: deploy.GetNamespace(),
+			},
+			Spec: autoscalingv1.ScaleSpec{
+				Replicas: *deploy.Spec.Replicas,
+			},
+		}
+		_, err := c.kubeclientset.AppsV1().Deployments(namespace).UpdateScale(deploy.GetName(), scale)
+		return err
+	case *appsv1.StatefulSet:
+		sts := workload.(*appsv1.StatefulSet)
+		scale := &autoscalingv1.Scale{
+			ObjectMeta: metav1.ObjectMeta{
+				Name:      sts.GetName(),
+				Namespace: sts.GetNamespace(),
+			},
+			Spec: autoscalingv1.ScaleSpec{
+				Replicas: *sts.Spec.Replicas,
+			},
+		}
+		_, err := c.kubeclientset.AppsV1().StatefulSets(namespace).UpdateScale(sts.GetName(), scale)
+		return err
+	default:
+		return fmt.Errorf("unsupported type %T", workload)
+	}
+}
+
+// isWaitingScaleUp tries to check whether PVC is waiting for restart Pod.
+func (c *VolumeExpansionController) isWaitingScaleUp(name, namespace string) bool {
+	pvc, err := c.pvcLister.PersistentVolumeClaims(namespace).Get(name)
+	if err != nil {
+		klog.Errorf("Get PVC error")
+	}
+	if pvc == nil {
+		return false
+	}
+	for _, condition := range pvc.Status.Conditions {
+		if condition.Type == corev1.PersistentVolumeClaimFileSystemResizePending {
+			return true
+		}
+	}
+	return false
+}

pkg/controller/storage/expansion/expansion_controller_test.go

@@ -0,0 +1,288 @@
+/*
+
+ Copyright 2019 The KubeSphere Authors.
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+
+*/
+
+package expansion
+
+import (
+	"encoding/json"
+	"flag"
+	"fmt"
+	appsv1 "k8s.io/api/apps/v1"
+	"k8s.io/api/core/v1"
+	storagev1 "k8s.io/api/storage/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/types"
+	"k8s.io/apimachinery/pkg/util/strategicpatch"
+	"k8s.io/apimachinery/pkg/util/wait"
+	"k8s.io/apimachinery/pkg/watch"
+	"k8s.io/client-go/informers"
+	"k8s.io/client-go/kubernetes/fake"
+	clientgotesting "k8s.io/client-go/testing"
+	"os"
+	"testing"
+	"time"
+)
+
+func TestMain(m *testing.M) {
+	flag.Set("alsologtostderr", "true")
+	flag.Set("log_dir", "/tmp")
+	flag.Set("v", "3")
+	flag.Parse()
+	ret := m.Run()
+	os.Exit(ret)
+}
+
+func TestSyncHandler(t *testing.T) {
+	retryTime = wait.Backoff{
+		Duration: 1 * time.Second,
+		Factor:   2,
+		Steps:    2,
+	}
+	tests := []struct {
+		name     string
+		pvc      *v1.PersistentVolumeClaim
+		pod      *v1.Pod
+		deploy   *appsv1.Deployment
+		rs       *appsv1.ReplicaSet
+		sts      *appsv1.StatefulSet
+		sc       *storagev1.StorageClass
+		pvcKey   string
+		hasError bool
+	}{
+		{
+			name: "mount pvc on deploy",
+			pvc:  getFakePersistentVolumeClaim("fake-pvc", "vol-12345", "fake-sc", types.UID(123)),
+			sc:   getFakeStorageClass("fake-sc", "fake.sc.com"),
+			deploy: getFakeDeployment("fake-deploy", "234", 1,
+				getFakePersistentVolumeClaim("fake-pvc", "vol-12345", "fake-sc", types.UID(123))),
+			pvcKey:   "default/fake-pvc",
+			hasError: false,
+		},
+		{
+			name:     "unmounted pvc",
+			pvc:      getFakePersistentVolumeClaim("fake-pvc", "vol-12345", "fake-sc", types.UID(123)),
+			sc:       getFakeStorageClass("fake-sc", "fake.sc.com"),
+			pvcKey:   "default/fake-pvc",
+			hasError: true,
+		},
+	}
+	for _, tc := range tests {
+		test := tc
+		fakeKubeClient := &fake.Clientset{}
+		fakeWatch := watch.NewFake()
+		fakeKubeClient.AddWatchReactor("*", clientgotesting.DefaultWatchReactor(fakeWatch, nil))
+		informerFactory := informers.NewSharedInformerFactory(fakeKubeClient, 0)
+		pvcInformer := informerFactory.Core().V1().PersistentVolumeClaims()
+		storageClassInformer := informerFactory.Storage().V1().StorageClasses()
+		podInformer := informerFactory.Core().V1().Pods()
+		deployInformer := informerFactory.Apps().V1().Deployments()
+		rsInformer := informerFactory.Apps().V1().ReplicaSets()
+		stsInformer := informerFactory.Apps().V1().StatefulSets()
+		pvc := tc.pvc
+
+		if tc.pvc != nil {
+			informerFactory.Core().V1().PersistentVolumeClaims().Informer().GetIndexer().Add(pvc)
+		}
+		if tc.sc != nil {
+			informerFactory.Storage().V1().StorageClasses().Informer().GetIndexer().Add(tc.sc)
+		}
+		if tc.deploy != nil {
+			informerFactory.Apps().V1().Deployments().Informer().GetIndexer().Add(tc.deploy)
+			tc.rs = generateReplicaSetFromDeployment(tc.deploy)
+		}
+		if tc.rs != nil {
+			informerFactory.Apps().V1().ReplicaSets().Informer().GetIndexer().Add(tc.rs)
+			tc.pod = generatePodFromReplicaSet(tc.rs)
+		}
+		if tc.sts != nil {
+			informerFactory.Apps().V1().StatefulSets().Informer().GetIndexer().Add(tc.sts)
+		}
+		if tc.pod != nil {
+			informerFactory.Core().V1().Pods().Informer().GetIndexer().Add(tc.pod)
+		}
+		expc := NewVolumeExpansionController(fakeKubeClient, pvcInformer, storageClassInformer, podInformer, deployInformer,
+			rsInformer, stsInformer)
+		fakeKubeClient.AddReactor("patch", "persistentvolumeclaims", func(action clientgotesting.Action) (bool, runtime.Object,
+			error) {
+			if action.GetSubresource() == "status" {
+				patchActionaction, _ := action.(clientgotesting.PatchAction)
+				pvc, err := applyPVCPatch(pvc, patchActionaction.GetPatch())
+				if err != nil {
+					return false, nil, err
+				}
+				return true, pvc, nil
+			}
+			return true, pvc, nil
+		})
+		err := expc.syncHandler(test.pvcKey)
+		if err != nil && !test.hasError {
+			t.Fatalf("for: %s; unexpected error while running handler : %v", test.name, err)
+		}
+	}
+}
+
+func applyPVCPatch(originalPVC *v1.PersistentVolumeClaim, patch []byte) (*v1.PersistentVolumeClaim, error) {
+	pvcData, err := json.Marshal(originalPVC)
+	if err != nil {
+		return nil, fmt.Errorf("failed to marshal pvc with %v", err)
+	}
+	updated, err := strategicpatch.StrategicMergePatch(pvcData, patch, v1.PersistentVolumeClaim{})
+	if err != nil {
+		return nil, fmt.Errorf("failed to apply patch on pvc %v", err)
+	}
+	updatedPVC := &v1.PersistentVolumeClaim{}
+	if err := json.Unmarshal(updated, updatedPVC); err != nil {
+		return nil, fmt.Errorf("failed to unmarshal updated pvc : %v", err)
+	}
+	return updatedPVC, nil
+}
+
+func getFakePersistentVolumeClaim(pvcName, volumeName, scName string, uid types.UID) *v1.PersistentVolumeClaim {
+	pvc := &v1.PersistentVolumeClaim{
+		ObjectMeta: metav1.ObjectMeta{Name: pvcName, Namespace: "default", UID: uid},
+		Spec:       v1.PersistentVolumeClaimSpec{},
+	}
+	if volumeName != "" {
+		pvc.Spec.VolumeName = volumeName
+	}
+
+	if scName != "" {
+		pvc.Spec.StorageClassName = &scName
+	}
+	return pvc
+}
+
+func getFakeStorageClass(scName, pluginName string) *storagev1.StorageClass {
+	return &storagev1.StorageClass{
+		ObjectMeta:  metav1.ObjectMeta{Name: scName},
+		Provisioner: pluginName,
+	}
+}
+
+func getFakePod(podName string, ownerRef *metav1.OwnerReference, uid types.UID) *v1.Pod {
+	pod := &v1.Pod{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:            podName,
+			Namespace:       "default",
+			UID:             uid,
+			OwnerReferences: []metav1.OwnerReference{*ownerRef},
+		},
+		Spec: v1.PodSpec{},
+	}
+	return pod
+}
+
+func getFakeReplicaSet(rsName string, ownerRef *metav1.OwnerReference, uid types.UID, replicas int) *appsv1.ReplicaSet {
+	rs := &appsv1.ReplicaSet{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:            rsName,
+			Namespace:       "default",
+			UID:             uid,
+			OwnerReferences: []metav1.OwnerReference{*ownerRef},
+		},
+		Spec: appsv1.ReplicaSetSpec{},
+	}
+	return rs
+}
+
+func getFakeDeployment(deployName string, uid types.UID, replicas int32, mountPVC *v1.PersistentVolumeClaim) *appsv1.
+	Deployment {
+	return &appsv1.Deployment{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      deployName,
+			Namespace: "default",
+		},
+		Spec: appsv1.DeploymentSpec{
+			Replicas: &replicas,
+			Template: v1.PodTemplateSpec{
+				Spec: v1.PodSpec{
+					Volumes: []v1.Volume{
+						{
+							Name: "test",
+							VolumeSource: v1.VolumeSource{
+								PersistentVolumeClaim: &v1.PersistentVolumeClaimVolumeSource{
+									ClaimName: mountPVC.GetName(),
+								},
+							},
+						},
+					},
+				},
+			},
+		},
+	}
+}
+
+func getFakeStatefulSet(stsName string, uid types.UID, replicas int32, mountPVC *v1.PersistentVolumeClaim) *appsv1.
+	StatefulSet {
+	return &appsv1.StatefulSet{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      stsName,
+			Namespace: "default",
+		},
+		Spec: appsv1.StatefulSetSpec{
+			Replicas: &replicas,
+			Template: v1.PodTemplateSpec{
+				Spec: v1.PodSpec{
+					Volumes: []v1.Volume{
+						{
+							Name: "test",
+							VolumeSource: v1.VolumeSource{
+								PersistentVolumeClaim: &v1.PersistentVolumeClaimVolumeSource{
+									ClaimName: mountPVC.GetName(),
+								},
+							},
+						},
+					},
+				},
+			},
+		},
+	}
+}
+
+// generatePodFromRS creates a pod, with the input ReplicaSet's selector and its template
+func generatePodFromReplicaSet(rs *appsv1.ReplicaSet) *v1.Pod {
+	trueVar := true
+	return &v1.Pod{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      rs.Name + "-pod",
+			Namespace: rs.Namespace,
+			OwnerReferences: []metav1.OwnerReference{
+				{UID: rs.UID, APIVersion: "v1beta1", Kind: "ReplicaSet", Name: rs.Name, Controller: &trueVar},
+			},
+		},
+		Spec: rs.Spec.Template.Spec,
+	}
+}
+
+func generateReplicaSetFromDeployment(deploy *appsv1.Deployment) *appsv1.ReplicaSet {
+	trueVar := true
+	return &appsv1.ReplicaSet{
+		ObjectMeta: metav1.ObjectMeta{
+			Name:      deploy.Name + "-rs",
+			Namespace: deploy.Namespace,
+			OwnerReferences: []metav1.OwnerReference{
+				{UID: deploy.UID, APIVersion: "v1beta1", Kind: "Deployment", Name: deploy.Name, Controller: &trueVar},
+			},
+		},
+		Spec: appsv1.ReplicaSetSpec{
+			Replicas: deploy.Spec.Replicas,
+			Template: deploy.Spec.Template,
+		},
+	}
+}

pkg/controller/storage/expansion/expansion_util.go

@@ -0,0 +1,66 @@
+/*
+
+ Copyright 2019 The KubeSphere Authors.
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+
+*/
+
+package expansion
+
+import (
+	"fmt"
+	corev1 "k8s.io/api/core/v1"
+	"k8s.io/klog"
+)
+
+func getPodMountPVC(pods []*corev1.Pod, pvc string) []*corev1.Pod {
+	var res []*corev1.Pod
+	for _, pod := range pods {
+		klog.V(4).Infof("check pod %s is mount pvc %s", pod.Name, pvc)
+		curPod := pod
+		if isMounted(pod, pvc) {
+			res = append(res, curPod)
+		}
+	}
+	return res
+}
+
+func isMounted(pod *corev1.Pod, pvc string) bool {
+	for _, vol := range pod.Spec.Volumes {
+		if vol.PersistentVolumeClaim != nil && vol.PersistentVolumeClaim.ClaimName == pvc {
+			return true
+		}
+	}
+	return false
+}
+
+// claimToClaimKey return namespace/name string for pvc
+func claimToClaimKey(claim *corev1.PersistentVolumeClaim) string {
+	return fmt.Sprintf("%s/%s", claim.Namespace, claim.Name)
+}
+
+// GetPersistentVolumeClaimClass returns StorageClassName. If no storage class was
+// requested, it returns "".
+func getPersistentVolumeClaimClass(claim *corev1.PersistentVolumeClaim) string {
+	// Use beta annotation first
+	if class, found := claim.Annotations[corev1.BetaStorageClassAnnotation]; found {
+		return class
+	}
+
+	if claim.Spec.StorageClassName != nil {
+		return *claim.Spec.StorageClassName
+	}
+
+	return ""
+}