Allow exponential backoff to save PVs to API server

Exponential backoff must be explicitly requested by provisioner.

controller/controller.go

@@ -131,6 +131,7 @@ type ProvisionController struct {
 	exponentialBackOffOnError bool
 	threadiness               int
 
+	createProvisionedPVBackoff    *wait.Backoff
 	createProvisionedPVRetryCount int
 	createProvisionedPVInterval   time.Duration
 
@@ -244,6 +245,9 @@ func CreateProvisionedPVRetryCount(createProvisionedPVRetryCount int) func(*Prov
 		if c.HasRun() {
 			return errRuntime
 		}
+		if c.createProvisionedPVBackoff != nil {
+			return fmt.Errorf("CreateProvisionedPVBackoff cannot be used together with CreateProvisionedPVRetryCount")
+		}
 		c.createProvisionedPVRetryCount = createProvisionedPVRetryCount
 		return nil
 	}
@@ -256,11 +260,34 @@ func CreateProvisionedPVInterval(createProvisionedPVInterval time.Duration) func
 		if c.HasRun() {
 			return errRuntime
 		}
+		if c.createProvisionedPVBackoff != nil {
+			return fmt.Errorf("CreateProvisionedPVBackoff cannot be used together with CreateProvisionedPVInterval")
+		}
 		c.createProvisionedPVInterval = createProvisionedPVInterval
 		return nil
 	}
 }
 
+// CreateProvisionedPVBackoff is the configuration of exponential backoff between retries when we create a
+// PV object for a provisioned volume. Defaults to linear backoff, 10 seconds 5 times.
+// Only one of CreateProvisionedPVInterval+CreateProvisionedPVRetryCount or CreateProvisionedPVBackoff
+// can be used.
+func CreateProvisionedPVBackoff(backoff wait.Backoff) func(*ProvisionController) error {
+	return func(c *ProvisionController) error {
+		if c.HasRun() {
+			return errRuntime
+		}
+		if c.createProvisionedPVRetryCount != 0 {
+			return fmt.Errorf("CreateProvisionedPVBackoff cannot be used together with CreateProvisionedPVRetryCount")
+		}
+		if c.createProvisionedPVInterval != 0 {
+			return fmt.Errorf("CreateProvisionedPVBackoff cannot be used together with CreateProvisionedPVInterval")
+		}
+		c.createProvisionedPVBackoff = &backoff
+		return nil
+	}
+}
+
 // FailedProvisionThreshold is the threshold for max number of retries on
 // failures of Provision. Set to 0 to retry indefinitely. Defaults to 15.
 func FailedProvisionThreshold(failedProvisionThreshold int) func(*ProvisionController) error {
@@ -452,34 +479,35 @@ func NewProvisionController(
 	eventRecorder := broadcaster.NewRecorder(scheme.Scheme, v1.EventSource{Component: component})
 
 	controller := &ProvisionController{
-		client:                        client,
-		provisionerName:               provisionerName,
-		provisioner:                   provisioner,
-		kubeVersion:                   utilversion.MustParseSemantic(kubeVersion),
-		id:                            id,
-		component:                     component,
-		eventRecorder:                 eventRecorder,
-		resyncPeriod:                  DefaultResyncPeriod,
-		exponentialBackOffOnError:     DefaultExponentialBackOffOnError,
-		threadiness:                   DefaultThreadiness,
-		createProvisionedPVRetryCount: DefaultCreateProvisionedPVRetryCount,
-		createProvisionedPVInterval:   DefaultCreateProvisionedPVInterval,
-		failedProvisionThreshold:      DefaultFailedProvisionThreshold,
-		failedDeleteThreshold:         DefaultFailedDeleteThreshold,
-		leaderElection:                DefaultLeaderElection,
-		leaderElectionNamespace:       getInClusterNamespace(),
-		leaseDuration:                 DefaultLeaseDuration,
-		renewDeadline:                 DefaultRenewDeadline,
-		retryPeriod:                   DefaultRetryPeriod,
-		metricsPort:                   DefaultMetricsPort,
-		metricsAddress:                DefaultMetricsAddress,
-		metricsPath:                   DefaultMetricsPath,
-		hasRun:                        false,
-		hasRunLock:                    &sync.Mutex{},
+		client:                    client,
+		provisionerName:           provisionerName,
+		provisioner:               provisioner,
+		kubeVersion:               utilversion.MustParseSemantic(kubeVersion),
+		id:                        id,
+		component:                 component,
+		eventRecorder:             eventRecorder,
+		resyncPeriod:              DefaultResyncPeriod,
+		exponentialBackOffOnError: DefaultExponentialBackOffOnError,
+		threadiness:               DefaultThreadiness,
+		failedProvisionThreshold:  DefaultFailedProvisionThreshold,
+		failedDeleteThreshold:     DefaultFailedDeleteThreshold,
+		leaderElection:            DefaultLeaderElection,
+		leaderElectionNamespace:   getInClusterNamespace(),
+		leaseDuration:             DefaultLeaseDuration,
+		renewDeadline:             DefaultRenewDeadline,
+		retryPeriod:               DefaultRetryPeriod,
+		metricsPort:               DefaultMetricsPort,
+		metricsAddress:            DefaultMetricsAddress,
+		metricsPath:               DefaultMetricsPath,
+		hasRun:                    false,
+		hasRunLock:                &sync.Mutex{},
 	}
 
 	for _, option := range options {
-		option(controller)
+		err := option(controller)
+		if err != nil {
+			glog.Fatalf("Error processing controller options: %s", err)
+		}
 	}
 
 	var rateLimiter workqueue.RateLimiter
@@ -500,6 +528,21 @@ func NewProvisionController(
 	controller.claimQueue = workqueue.NewNamedRateLimitingQueue(rateLimiter, "claims")
 	controller.volumeQueue = workqueue.NewNamedRateLimitingQueue(rateLimiter, "volumes")
 
+	if controller.createProvisionedPVBackoff == nil {
+		// Use linear backoff with createProvisionedPVInterval and createProvisionedPVRetryCount by default.
+		if controller.createProvisionedPVInterval == 0 {
+			controller.createProvisionedPVInterval = DefaultCreateProvisionedPVInterval
+		}
+		if controller.createProvisionedPVRetryCount == 0 {
+			controller.createProvisionedPVRetryCount = DefaultCreateProvisionedPVRetryCount
+		}
+		controller.createProvisionedPVBackoff = &wait.Backoff{
+			Duration: controller.createProvisionedPVInterval,
+			Factor:   1, // linear backoff
+			Steps:    controller.createProvisionedPVRetryCount,
+		}
+	}
+
 	informer := informers.NewSharedInformerFactory(client, controller.resyncPeriod)
 
 	// ----------------------
@@ -1083,47 +1126,49 @@ func (ctrl *ProvisionController) provisionClaimOperation(claim *v1.PersistentVol
 	}
 
 	// Try to create the PV object several times
-	for i := 0; i < ctrl.createProvisionedPVRetryCount; i++ {
+	var lastSaveError error
+	err = wait.ExponentialBackoff(*ctrl.createProvisionedPVBackoff, func() (bool, error) {
 		glog.Info(logOperation(operation, "trying to save persistentvolume %q", volume.Name))
 		if _, err = ctrl.client.CoreV1().PersistentVolumes().Create(volume); err == nil || apierrs.IsAlreadyExists(err) {
 			// Save succeeded.
 			if err != nil {
 				glog.Info(logOperation(operation, "persistentvolume %q already exists, reusing", volume.Name))
-				err = nil
 			} else {
 				glog.Info(logOperation(operation, "persistentvolume %q saved", volume.Name))
 			}
-			break
+			return true, nil
 		}
 		// Save failed, try again after a while.
 		glog.Info(logOperation(operation, "failed to save persistentvolume %q: %v", volume.Name, err))
-		time.Sleep(ctrl.createProvisionedPVInterval)
-	}
+		lastSaveError = err
+		return false, nil
+	})
 
 	if err != nil {
 		// Save failed. Now we have a storage asset outside of Kubernetes,
 		// but we don't have appropriate PV object for it.
 		// Emit some event here and try to delete the storage asset several
 		// times.
-		strerr := fmt.Sprintf("Error creating provisioned PV object for claim %s: %v. Deleting the volume.", claimToClaimKey(claim), err)
+		strerr := fmt.Sprintf("Error creating provisioned PV object for claim %s: %v. Deleting the volume.", claimToClaimKey(claim), lastSaveError)
 		glog.Error(logOperation(operation, strerr))
 		ctrl.eventRecorder.Event(claim, v1.EventTypeWarning, "ProvisioningFailed", strerr)
 
-		for i := 0; i < ctrl.createProvisionedPVRetryCount; i++ {
+		var lastDeleteError error
+		err = wait.ExponentialBackoff(*ctrl.createProvisionedPVBackoff, func() (bool, error) {
 			if err = ctrl.provisioner.Delete(volume); err == nil {
 				// Delete succeeded
 				glog.Info(logOperation(operation, "cleaning volume %q succeeded", volume.Name))
-				break
+				return true, nil
 			}
 			// Delete failed, try again after a while.
 			glog.Info(logOperation(operation, "failed to clean volume %q: %v", volume.Name, err))
-			time.Sleep(ctrl.createProvisionedPVInterval)
-		}
-
+			lastDeleteError = err
+			return false, nil
+		})
 		if err != nil {
 			// Delete failed several times. There is an orphaned volume and there
 			// is nothing we can do about it.
-			strerr := fmt.Sprintf("Error cleaning provisioned volume for claim %s: %v. Please delete manually.", claimToClaimKey(claim), err)
+			strerr := fmt.Sprintf("Error cleaning provisioned volume for claim %s: %v. Please delete manually.", claimToClaimKey(claim), lastDeleteError)
 			glog.Error(logOperation(operation, strerr))
 			ctrl.eventRecorder.Event(claim, v1.EventTypeWarning, "ProvisioningCleanupFailed", strerr)
 		}