Files
external-snapshotter/pkg/common-controller/snapshot_controller_base.go
2019-12-20 02:35:54 +00:00

467 lines
17 KiB
Go

/*
Copyright 2019 The Kubernetes 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 common_controller
import (
"fmt"
"time"
crdv1 "github.com/kubernetes-csi/external-snapshotter/pkg/apis/volumesnapshot/v1beta1"
clientset "github.com/kubernetes-csi/external-snapshotter/pkg/client/clientset/versioned"
storageinformers "github.com/kubernetes-csi/external-snapshotter/pkg/client/informers/externalversions/volumesnapshot/v1beta1"
storagelisters "github.com/kubernetes-csi/external-snapshotter/pkg/client/listers/volumesnapshot/v1beta1"
"github.com/kubernetes-csi/external-snapshotter/pkg/utils"
"k8s.io/api/core/v1"
"k8s.io/apimachinery/pkg/api/errors"
"k8s.io/apimachinery/pkg/labels"
"k8s.io/apimachinery/pkg/util/wait"
coreinformers "k8s.io/client-go/informers/core/v1"
"k8s.io/client-go/kubernetes"
"k8s.io/client-go/kubernetes/scheme"
corev1 "k8s.io/client-go/kubernetes/typed/core/v1"
corelisters "k8s.io/client-go/listers/core/v1"
"k8s.io/client-go/tools/cache"
"k8s.io/client-go/tools/record"
"k8s.io/client-go/util/workqueue"
"k8s.io/klog"
"k8s.io/kubernetes/pkg/util/goroutinemap"
)
// Number of retries when we create a VolumeSnapshotContent object
const createSnapshotContentRetryCount = 5
// Interval between retries when we create a VolumeSnapshotContent object
const createSnapshotContentInterval = 10 * time.Second
type csiSnapshotCommonController struct {
clientset clientset.Interface
client kubernetes.Interface
eventRecorder record.EventRecorder
snapshotQueue workqueue.RateLimitingInterface
contentQueue workqueue.RateLimitingInterface
snapshotLister storagelisters.VolumeSnapshotLister
snapshotListerSynced cache.InformerSynced
contentLister storagelisters.VolumeSnapshotContentLister
contentListerSynced cache.InformerSynced
classLister storagelisters.VolumeSnapshotClassLister
classListerSynced cache.InformerSynced
pvcLister corelisters.PersistentVolumeClaimLister
pvcListerSynced cache.InformerSynced
snapshotStore cache.Store
contentStore cache.Store
// Map of scheduled/running operations.
runningOperations goroutinemap.GoRoutineMap
createSnapshotContentRetryCount int
createSnapshotContentInterval time.Duration
resyncPeriod time.Duration
}
// NewCSISnapshotController returns a new *csiSnapshotCommonController
func NewCSISnapshotCommonController(
clientset clientset.Interface,
client kubernetes.Interface,
volumeSnapshotInformer storageinformers.VolumeSnapshotInformer,
volumeSnapshotContentInformer storageinformers.VolumeSnapshotContentInformer,
volumeSnapshotClassInformer storageinformers.VolumeSnapshotClassInformer,
pvcInformer coreinformers.PersistentVolumeClaimInformer,
resyncPeriod time.Duration,
) *csiSnapshotCommonController {
broadcaster := record.NewBroadcaster()
broadcaster.StartLogging(klog.Infof)
broadcaster.StartRecordingToSink(&corev1.EventSinkImpl{Interface: client.CoreV1().Events(v1.NamespaceAll)})
var eventRecorder record.EventRecorder
eventRecorder = broadcaster.NewRecorder(scheme.Scheme, v1.EventSource{Component: fmt.Sprintf("snapshot-controller")})
ctrl := &csiSnapshotCommonController{
clientset: clientset,
client: client,
eventRecorder: eventRecorder,
runningOperations: goroutinemap.NewGoRoutineMap(true),
createSnapshotContentRetryCount: createSnapshotContentRetryCount,
createSnapshotContentInterval: createSnapshotContentInterval,
resyncPeriod: resyncPeriod,
snapshotStore: cache.NewStore(cache.DeletionHandlingMetaNamespaceKeyFunc),
contentStore: cache.NewStore(cache.DeletionHandlingMetaNamespaceKeyFunc),
snapshotQueue: workqueue.NewNamedRateLimitingQueue(workqueue.DefaultControllerRateLimiter(), "snapshot-controller-snapshot"),
contentQueue: workqueue.NewNamedRateLimitingQueue(workqueue.DefaultControllerRateLimiter(), "snapshot-controller-content"),
}
ctrl.pvcLister = pvcInformer.Lister()
ctrl.pvcListerSynced = pvcInformer.Informer().HasSynced
volumeSnapshotInformer.Informer().AddEventHandlerWithResyncPeriod(
cache.ResourceEventHandlerFuncs{
AddFunc: func(obj interface{}) { ctrl.enqueueSnapshotWork(obj) },
UpdateFunc: func(oldObj, newObj interface{}) { ctrl.enqueueSnapshotWork(newObj) },
DeleteFunc: func(obj interface{}) { ctrl.enqueueSnapshotWork(obj) },
},
ctrl.resyncPeriod,
)
ctrl.snapshotLister = volumeSnapshotInformer.Lister()
ctrl.snapshotListerSynced = volumeSnapshotInformer.Informer().HasSynced
volumeSnapshotContentInformer.Informer().AddEventHandlerWithResyncPeriod(
cache.ResourceEventHandlerFuncs{
AddFunc: func(obj interface{}) { ctrl.enqueueContentWork(obj) },
UpdateFunc: func(oldObj, newObj interface{}) { ctrl.enqueueContentWork(newObj) },
DeleteFunc: func(obj interface{}) { ctrl.enqueueContentWork(obj) },
},
ctrl.resyncPeriod,
)
ctrl.contentLister = volumeSnapshotContentInformer.Lister()
ctrl.contentListerSynced = volumeSnapshotContentInformer.Informer().HasSynced
ctrl.classLister = volumeSnapshotClassInformer.Lister()
ctrl.classListerSynced = volumeSnapshotClassInformer.Informer().HasSynced
return ctrl
}
func (ctrl *csiSnapshotCommonController) Run(workers int, stopCh <-chan struct{}) {
defer ctrl.snapshotQueue.ShutDown()
defer ctrl.contentQueue.ShutDown()
klog.Infof("Starting snapshot controller")
defer klog.Infof("Shutting snapshot controller")
if !cache.WaitForCacheSync(stopCh, ctrl.snapshotListerSynced, ctrl.contentListerSynced, ctrl.classListerSynced, ctrl.pvcListerSynced) {
klog.Errorf("Cannot sync caches")
return
}
ctrl.initializeCaches(ctrl.snapshotLister, ctrl.contentLister)
for i := 0; i < workers; i++ {
go wait.Until(ctrl.snapshotWorker, 0, stopCh)
go wait.Until(ctrl.contentWorker, 0, stopCh)
}
<-stopCh
}
// enqueueSnapshotWork adds snapshot to given work queue.
func (ctrl *csiSnapshotCommonController) enqueueSnapshotWork(obj interface{}) {
// Beware of "xxx deleted" events
if unknown, ok := obj.(cache.DeletedFinalStateUnknown); ok && unknown.Obj != nil {
obj = unknown.Obj
}
if snapshot, ok := obj.(*crdv1.VolumeSnapshot); ok {
objName, err := cache.DeletionHandlingMetaNamespaceKeyFunc(snapshot)
if err != nil {
klog.Errorf("failed to get key from object: %v, %v", err, snapshot)
return
}
klog.V(5).Infof("enqueued %q for sync", objName)
ctrl.snapshotQueue.Add(objName)
}
}
// enqueueContentWork adds snapshot content to given work queue.
func (ctrl *csiSnapshotCommonController) enqueueContentWork(obj interface{}) {
// Beware of "xxx deleted" events
if unknown, ok := obj.(cache.DeletedFinalStateUnknown); ok && unknown.Obj != nil {
obj = unknown.Obj
}
if content, ok := obj.(*crdv1.VolumeSnapshotContent); ok {
objName, err := cache.DeletionHandlingMetaNamespaceKeyFunc(content)
if err != nil {
klog.Errorf("failed to get key from object: %v, %v", err, content)
return
}
klog.V(5).Infof("enqueued %q for sync", objName)
ctrl.contentQueue.Add(objName)
}
}
// snapshotWorker processes items from snapshotQueue. It must run only once,
// syncSnapshot is not assured to be reentrant.
func (ctrl *csiSnapshotCommonController) snapshotWorker() {
workFunc := func() bool {
keyObj, quit := ctrl.snapshotQueue.Get()
if quit {
return true
}
defer ctrl.snapshotQueue.Done(keyObj)
key := keyObj.(string)
klog.V(5).Infof("snapshotWorker[%s]", key)
namespace, name, err := cache.SplitMetaNamespaceKey(key)
klog.V(5).Infof("snapshotWorker: snapshot namespace [%s] name [%s]", namespace, name)
if err != nil {
klog.Errorf("error getting namespace & name of snapshot %q to get snapshot from informer: %v", key, err)
return false
}
snapshot, err := ctrl.snapshotLister.VolumeSnapshots(namespace).Get(name)
if err == nil {
// The volume snapshot still exists in informer cache, the event must have
// been add/update/sync
newSnapshot, err := ctrl.checkAndUpdateSnapshotClass(snapshot)
if err == nil {
klog.V(5).Infof("passed checkAndUpdateSnapshotClass for snapshot %q", key)
ctrl.updateSnapshot(newSnapshot)
}
return false
}
if err != nil && !errors.IsNotFound(err) {
klog.V(2).Infof("error getting snapshot %q from informer: %v", key, err)
return false
}
// The snapshot is not in informer cache, the event must have been "delete"
vsObj, found, err := ctrl.snapshotStore.GetByKey(key)
if err != nil {
klog.V(2).Infof("error getting snapshot %q from cache: %v", key, err)
return false
}
if !found {
// The controller has already processed the delete event and
// deleted the snapshot from its cache
klog.V(2).Infof("deletion of snapshot %q was already processed", key)
return false
}
snapshot, ok := vsObj.(*crdv1.VolumeSnapshot)
if !ok {
klog.Errorf("expected vs, got %+v", vsObj)
return false
}
newSnapshot, err := ctrl.checkAndUpdateSnapshotClass(snapshot)
if err == nil {
ctrl.deleteSnapshot(newSnapshot)
}
return false
}
for {
if quit := workFunc(); quit {
klog.Infof("snapshot worker queue shutting down")
return
}
}
}
// contentWorker processes items from contentQueue. It must run only once,
// syncContent is not assured to be reentrant.
func (ctrl *csiSnapshotCommonController) contentWorker() {
workFunc := func() bool {
keyObj, quit := ctrl.contentQueue.Get()
if quit {
return true
}
defer ctrl.contentQueue.Done(keyObj)
key := keyObj.(string)
klog.V(5).Infof("contentWorker[%s]", key)
_, name, err := cache.SplitMetaNamespaceKey(key)
if err != nil {
klog.V(4).Infof("error getting name of snapshotContent %q to get snapshotContent from informer: %v", key, err)
return false
}
content, err := ctrl.contentLister.Get(name)
// The content still exists in informer cache, the event must have
// been add/update/sync
if err == nil {
ctrl.updateContent(content)
return false
}
if !errors.IsNotFound(err) {
klog.V(2).Infof("error getting content %q from informer: %v", key, err)
return false
}
// The content is not in informer cache, the event must have been
// "delete"
contentObj, found, err := ctrl.contentStore.GetByKey(key)
if err != nil {
klog.V(2).Infof("error getting content %q from cache: %v", key, err)
return false
}
if !found {
// The controller has already processed the delete event and
// deleted the content from its cache
klog.V(2).Infof("deletion of content %q was already processed", key)
return false
}
content, ok := contentObj.(*crdv1.VolumeSnapshotContent)
if !ok {
klog.Errorf("expected content, got %+v", content)
return false
}
ctrl.deleteContent(content)
return false
}
for {
if quit := workFunc(); quit {
klog.Infof("content worker queue shutting down")
return
}
}
}
// checkAndUpdateSnapshotClass gets the VolumeSnapshotClass from VolumeSnapshot. If it is not set,
// gets it from default VolumeSnapshotClass and sets it.
func (ctrl *csiSnapshotCommonController) checkAndUpdateSnapshotClass(snapshot *crdv1.VolumeSnapshot) (*crdv1.VolumeSnapshot, error) {
className := snapshot.Spec.VolumeSnapshotClassName
var class *crdv1.VolumeSnapshotClass
var err error
newSnapshot := snapshot
if className != nil {
klog.V(5).Infof("checkAndUpdateSnapshotClass [%s]: VolumeSnapshotClassName [%s]", snapshot.Name, *className)
class, err = ctrl.getSnapshotClass(*className)
if err != nil {
klog.Errorf("checkAndUpdateSnapshotClass failed to getSnapshotClass %v", err)
ctrl.updateSnapshotErrorStatusWithEvent(snapshot, v1.EventTypeWarning, "GetSnapshotClassFailed", fmt.Sprintf("Failed to get snapshot class with error %v", err))
return nil, err
}
} else {
klog.V(5).Infof("checkAndUpdateSnapshotClass [%s]: SetDefaultSnapshotClass", snapshot.Name)
class, newSnapshot, err = ctrl.SetDefaultSnapshotClass(snapshot)
if err != nil {
klog.Errorf("checkAndUpdateSnapshotClass failed to setDefaultClass %v", err)
ctrl.updateSnapshotErrorStatusWithEvent(snapshot, v1.EventTypeWarning, "SetDefaultSnapshotClassFailed", fmt.Sprintf("Failed to set default snapshot class with error %v", err))
return nil, err
}
}
// For pre-provisioned snapshots, we may not have snapshot class
if class != nil {
klog.V(5).Infof("VolumeSnapshotClass [%s] Driver [%s]", class.Name, class.Driver)
}
return newSnapshot, nil
}
// updateSnapshot runs in worker thread and handles "snapshot added",
// "snapshot updated" and "periodic sync" events.
func (ctrl *csiSnapshotCommonController) updateSnapshot(snapshot *crdv1.VolumeSnapshot) {
// Store the new snapshot version in the cache and do not process it if this is
// an old version.
klog.V(5).Infof("updateSnapshot %q", utils.SnapshotKey(snapshot))
newSnapshot, err := ctrl.storeSnapshotUpdate(snapshot)
if err != nil {
klog.Errorf("%v", err)
}
if !newSnapshot {
return
}
err = ctrl.syncSnapshot(snapshot)
if err != nil {
if errors.IsConflict(err) {
// Version conflict error happens quite often and the controller
// recovers from it easily.
klog.V(3).Infof("could not sync claim %q: %+v", utils.SnapshotKey(snapshot), err)
} else {
klog.Errorf("could not sync volume %q: %+v", utils.SnapshotKey(snapshot), err)
}
}
}
// updateContent runs in worker thread and handles "content added",
// "content updated" and "periodic sync" events.
func (ctrl *csiSnapshotCommonController) updateContent(content *crdv1.VolumeSnapshotContent) {
// Store the new content version in the cache and do not process it if this is
// an old version.
new, err := ctrl.storeContentUpdate(content)
if err != nil {
klog.Errorf("%v", err)
}
if !new {
return
}
err = ctrl.syncContent(content)
if err != nil {
if errors.IsConflict(err) {
// Version conflict error happens quite often and the controller
// recovers from it easily.
klog.V(3).Infof("could not sync content %q: %+v", content.Name, err)
} else {
klog.Errorf("could not sync content %q: %+v", content.Name, err)
}
}
}
// deleteSnapshot runs in worker thread and handles "snapshot deleted" event.
func (ctrl *csiSnapshotCommonController) deleteSnapshot(snapshot *crdv1.VolumeSnapshot) {
_ = ctrl.snapshotStore.Delete(snapshot)
klog.V(4).Infof("snapshot %q deleted", utils.SnapshotKey(snapshot))
snapshotContentName := ""
if snapshot.Status != nil && snapshot.Status.BoundVolumeSnapshotContentName != nil {
snapshotContentName = *snapshot.Status.BoundVolumeSnapshotContentName
}
if snapshotContentName == "" {
klog.V(5).Infof("deleteSnapshot[%q]: content not bound", utils.SnapshotKey(snapshot))
return
}
// sync the content when its snapshot is deleted. Explicitly sync'ing the
// content here in response to snapshot deletion prevents the content from
// waiting until the next sync period for its Release.
klog.V(5).Infof("deleteSnapshot[%q]: scheduling sync of content %s", utils.SnapshotKey(snapshot), snapshotContentName)
ctrl.contentQueue.Add(snapshotContentName)
}
// deleteContent runs in worker thread and handles "content deleted" event.
func (ctrl *csiSnapshotCommonController) deleteContent(content *crdv1.VolumeSnapshotContent) {
_ = ctrl.contentStore.Delete(content)
klog.V(4).Infof("content %q deleted", content.Name)
snapshotName := utils.SnapshotRefKey(&content.Spec.VolumeSnapshotRef)
if snapshotName == "" {
klog.V(5).Infof("deleteContent[%q]: content not bound", content.Name)
return
}
// sync the snapshot when its content is deleted. Explicitly sync'ing the
// snapshot here in response to content deletion prevents the snapshot from
// waiting until the next sync period for its Release.
klog.V(5).Infof("deleteContent[%q]: scheduling sync of snapshot %s", content.Name, snapshotName)
ctrl.snapshotQueue.Add(snapshotName)
}
// initializeCaches fills all controller caches with initial data from etcd in
// order to have the caches already filled when first addSnapshot/addContent to
// perform initial synchronization of the controller.
func (ctrl *csiSnapshotCommonController) initializeCaches(snapshotLister storagelisters.VolumeSnapshotLister, contentLister storagelisters.VolumeSnapshotContentLister) {
snapshotList, err := snapshotLister.List(labels.Everything())
if err != nil {
klog.Errorf("CSISnapshotController can't initialize caches: %v", err)
return
}
for _, snapshot := range snapshotList {
snapshotClone := snapshot.DeepCopy()
if _, err = ctrl.storeSnapshotUpdate(snapshotClone); err != nil {
klog.Errorf("error updating volume snapshot cache: %v", err)
}
}
contentList, err := contentLister.List(labels.Everything())
if err != nil {
klog.Errorf("CSISnapshotController can't initialize caches: %v", err)
return
}
for _, content := range contentList {
contentClone := content.DeepCopy()
if _, err = ctrl.storeContentUpdate(contentClone); err != nil {
klog.Errorf("error updating volume snapshot content cache: %v", err)
}
}
klog.V(4).Infof("controller initialized")
}