Merge pull request #27128 from markturansky/disable_provisioning

Automatic merge from submit-queue

Allow disabling of dynamic provisioning

Allow administrators to opt-out of dynamic provisioning.  Provisioning is still on by default, which is the current behavior.

Per a conversation with @jsafrane, a boolean toggle was added and plumbed through into the controller.  Deliberate disabling will simply return nil from `provisionClaim` whereas a misconfigured provisioner will continue on and generate error events for the PVC.

@kubernetes/rh-storage @saad-ali @thockin  @abhgupta

pkg/controller/persistentvolume/controller.go

@@ -106,18 +106,19 @@ const createProvisionedPVInterval = 10 * time.Second
 // framework.Controllers that watch PersistentVolume and PersistentVolumeClaim
 // changes.
 type PersistentVolumeController struct {
-	volumeController       *framework.Controller
-	volumeControllerStopCh chan struct{}
-	volumeSource           cache.ListerWatcher
-	claimController        *framework.Controller
-	claimControllerStopCh  chan struct{}
-	claimSource            cache.ListerWatcher
-	kubeClient             clientset.Interface
-	eventRecorder          record.EventRecorder
-	cloud                  cloudprovider.Interface
-	recyclePluginMgr       vol.VolumePluginMgr
-	provisioner            vol.ProvisionableVolumePlugin
-	clusterName            string
+	volumeController          *framework.Controller
+	volumeControllerStopCh    chan struct{}
+	volumeSource              cache.ListerWatcher
+	claimController           *framework.Controller
+	claimControllerStopCh     chan struct{}
+	claimSource               cache.ListerWatcher
+	kubeClient                clientset.Interface
+	eventRecorder             record.EventRecorder
+	cloud                     cloudprovider.Interface
+	recyclePluginMgr          vol.VolumePluginMgr
+	provisioner               vol.ProvisionableVolumePlugin
+	enableDynamicProvisioning bool
+	clusterName               string
 
 	// Cache of the last known version of volumes and claims. This cache is
 	// thread safe as long as the volumes/claims there are not modified, they
@@ -1062,8 +1063,11 @@ func (ctrl *PersistentVolumeController) doDeleteVolume(volume *api.PersistentVol
 	return nil
 }
 
-// provisionClaim starts new asynchronous operation to provision a claim.
+// provisionClaim starts new asynchronous operation to provision a claim if provisioning is enabled.
 func (ctrl *PersistentVolumeController) provisionClaim(claim *api.PersistentVolumeClaim) error {
+	if !ctrl.enableDynamicProvisioning {
+		return nil
+	}
 	glog.V(4).Infof("provisionClaim[%s]: started", claimToClaimKey(claim))
 	opName := fmt.Sprintf("provision-%s[%s]", claimToClaimKey(claim), string(claim.UID))
 	ctrl.scheduleOperation(opName, func() error {

pkg/controller/persistentvolume/controller_base.go

@@ -52,6 +52,7 @@ func NewPersistentVolumeController(
 	clusterName string,
 	volumeSource, claimSource cache.ListerWatcher,
 	eventRecorder record.EventRecorder,
+	enableDynamicProvisioning bool,
 ) *PersistentVolumeController {
 
 	if eventRecorder == nil {
@@ -68,6 +69,7 @@ func NewPersistentVolumeController(
 		runningOperations:             goroutinemap.NewGoRoutineMap(),
 		cloud:                         cloud,
 		provisioner:                   provisioner,
+		enableDynamicProvisioning:     enableDynamicProvisioning,
 		clusterName:                   clusterName,
 		createProvisionedPVRetryCount: createProvisionedPVRetryCount,
 		createProvisionedPVInterval:   createProvisionedPVInterval,

pkg/controller/persistentvolume/controller_test.go

@@ -164,7 +164,7 @@ func TestControllerSync(t *testing.T) {
 		client := &fake.Clientset{}
 		volumeSource := framework.NewFakeControllerSource()
 		claimSource := framework.NewFakeControllerSource()
-		ctrl := newTestController(client, volumeSource, claimSource)
+		ctrl := newTestController(client, volumeSource, claimSource, true)
 		reactor := newVolumeReactor(client, ctrl, volumeSource, claimSource, test.errors)
 		for _, claim := range test.initialClaims {
 			claimSource.Add(claim)

pkg/controller/persistentvolume/framework_test.go

@@ -555,7 +555,7 @@ func newVolumeReactor(client *fake.Clientset, ctrl *PersistentVolumeController,
 	return reactor
 }
 
-func newTestController(kubeClient clientset.Interface, volumeSource, claimSource cache.ListerWatcher) *PersistentVolumeController {
+func newTestController(kubeClient clientset.Interface, volumeSource, claimSource cache.ListerWatcher, enableDynamicProvisioning bool) *PersistentVolumeController {
 	if volumeSource == nil {
 		volumeSource = framework.NewFakeControllerSource()
 	}
@@ -572,6 +572,7 @@ func newTestController(kubeClient clientset.Interface, volumeSource, claimSource
 		volumeSource,
 		claimSource,
 		record.NewFakeRecorder(1000), // event recorder
+		enableDynamicProvisioning,
 	)
 
 	// Speed up the test
@@ -830,7 +831,7 @@ func runSyncTests(t *testing.T, tests []controllerTest) {
 
 		// Initialize the controller
 		client := &fake.Clientset{}
-		ctrl := newTestController(client, nil, nil)
+		ctrl := newTestController(client, nil, nil, true)
 		reactor := newVolumeReactor(client, ctrl, nil, nil, test.errors)
 		for _, claim := range test.initialClaims {
 			ctrl.claims.Add(claim)
@@ -874,7 +875,7 @@ func runMultisyncTests(t *testing.T, tests []controllerTest) {
 
 		// Initialize the controller
 		client := &fake.Clientset{}
-		ctrl := newTestController(client, nil, nil)
+		ctrl := newTestController(client, nil, nil, true)
 		reactor := newVolumeReactor(client, ctrl, nil, nil, test.errors)
 		for _, claim := range test.initialClaims {
 			ctrl.claims.Add(claim)

pkg/controller/persistentvolume/options/options.go

@@ -35,6 +35,7 @@ type VolumeConfigFlags struct {
 	PersistentVolumeRecyclerMinimumTimeoutHostPath      int
 	PersistentVolumeRecyclerIncrementTimeoutHostPath    int
 	EnableHostPathProvisioning                          bool
+	EnableDynamicProvisioning                           bool
 }
 
 type PersistentVolumeControllerOptions struct {
@@ -53,6 +54,7 @@ func NewPersistentVolumeControllerOptions() PersistentVolumeControllerOptions {
 			PersistentVolumeRecyclerMinimumTimeoutHostPath:   60,
 			PersistentVolumeRecyclerIncrementTimeoutHostPath: 30,
 			EnableHostPathProvisioning:                       false,
+			EnableDynamicProvisioning:                        true,
 		},
 	}
 }
@@ -84,4 +86,6 @@ func (o *PersistentVolumeControllerOptions) AddFlags(fs *pflag.FlagSet) {
 	fs.BoolVar(&o.VolumeConfigFlags.EnableHostPathProvisioning, "enable-hostpath-provisioner", o.VolumeConfigFlags.EnableHostPathProvisioning,
 		"Enable HostPath PV provisioning when running without a cloud provider. This allows testing and development of provisioning features. "+
 			"HostPath provisioning is not supported in any way, won't work in a multi-node cluster, and should not be used for anything other than testing or development.")
+	fs.BoolVar(&o.VolumeConfigFlags.EnableDynamicProvisioning, "enable-dynamic-provisioning", o.VolumeConfigFlags.EnableDynamicProvisioning,
+		"Enable dynamic provisioning for environments that support it.")
 }

pkg/controller/persistentvolume/provision_test.go

@@ -254,3 +254,12 @@ func TestProvisionMultiSync(t *testing.T) {
 
 	runMultisyncTests(t, tests)
 }
+
+// When provisioning is disabled, provisioning a claim should instantly return nil
+func TestDisablingDynamicProvisioner(t *testing.T) {
+	ctrl := newTestController(nil, nil, nil, false)
+	retVal := ctrl.provisionClaim(nil)
+	if retVal != nil {
+		t.Errorf("Expected nil return but got %v", retVal)
+	}
+}