Fix handling of APIserver errors when saving provisioned PVs.

pkg/controller/volume/persistentvolume/BUILD

@@ -62,12 +62,14 @@ go_test(
     ],
     library = ":go_default_library",
     deps = [
+        "//pkg/api:go_default_library",
         "//pkg/api/testapi:go_default_library",
         "//pkg/controller:go_default_library",
         "//pkg/volume:go_default_library",
         "//vendor/github.com/golang/glog:go_default_library",
         "//vendor/k8s.io/api/core/v1:go_default_library",
         "//vendor/k8s.io/api/storage/v1:go_default_library",
+        "//vendor/k8s.io/apimachinery/pkg/api/errors:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/api/resource:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/apis/meta/v1:go_default_library",
         "//vendor/k8s.io/apimachinery/pkg/runtime:go_default_library",

pkg/controller/volume/persistentvolume/provision_test.go

@@ -22,7 +22,9 @@ import (
 
 	"k8s.io/api/core/v1"
 	storage "k8s.io/api/storage/v1"
+	apierrs "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/kubernetes/pkg/api"
 )
 
 var class1Parameters = map[string]string{
@@ -360,6 +362,36 @@ func TestProvisionSync(t *testing.T) {
 			[]string{"Warning ProvisioningFailed"},
 			noerrors, wrapTestWithProvisionCalls([]provisionCall{}, testSyncClaim),
 		},
+		{
+			// Provision success - first save of a PV to API server fails (API
+			// server has written the object to etcd, but crashed before sending
+			// 200 OK response to the controller). Controller retries and the
+			// second save of the PV returns "AlreadyExists" because the PV
+			// object already is in the API server.
+			//
+			"11-19 - provisioned volume saved but API server crashed",
+			novolumes,
+			// We don't actually simulate API server saving the object and
+			// crashing afterwards, Create() just returns error without saving
+			// the volume in this test. So the set of expected volumes at the
+			// end of the test is empty.
+			novolumes,
+			newClaimArray("claim11-19", "uid11-19", "1Gi", "", v1.ClaimPending, &classGold),
+			newClaimArray("claim11-19", "uid11-19", "1Gi", "", v1.ClaimPending, &classGold, annStorageProvisioner),
+			noevents,
+			[]reactorError{
+				// Inject errors to simulate crashed API server during
+				// kubeclient.PersistentVolumes.Create()
+				{"create", "persistentvolumes", errors.New("Mock creation error1")},
+				{"create", "persistentvolumes", apierrs.NewAlreadyExists(api.Resource("persistentvolumes"), "")},
+			},
+			wrapTestWithPluginCalls(
+				nil, // recycle calls
+				nil, // delete calls - if Delete was called the test would fail
+				[]provisionCall{provision1Success},
+				testSyncClaim,
+			),
+		},
 	}
 	runSyncTests(t, tests, storageClasses)
 }

pkg/controller/volume/persistentvolume/pv_controller.go

@@ -24,6 +24,7 @@ import (
 
 	"k8s.io/api/core/v1"
 	storage "k8s.io/api/storage/v1"
+	apierrs "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	clientset "k8s.io/client-go/kubernetes"
 	"k8s.io/client-go/kubernetes/scheme"
@@ -1364,14 +1365,19 @@ func (ctrl *PersistentVolumeController) provisionClaimOperation(claimObj interfa
 	for i := 0; i < ctrl.createProvisionedPVRetryCount; i++ {
 		glog.V(4).Infof("provisionClaimOperation [%s]: trying to save volume %s", claimToClaimKey(claim), volume.Name)
 		var newVol *v1.PersistentVolume
-		if newVol, err = ctrl.kubeClient.Core().PersistentVolumes().Create(volume); err == nil {
+		if newVol, err = ctrl.kubeClient.Core().PersistentVolumes().Create(volume); err == nil || apierrs.IsAlreadyExists(err) {
 			// Save succeeded.
-			glog.V(3).Infof("volume %q for claim %q saved", volume.Name, claimToClaimKey(claim))
+			if err != nil {
+				glog.V(3).Infof("volume %q for claim %q already exists, reusing", volume.Name, claimToClaimKey(claim))
+				err = nil
+			} else {
+				glog.V(3).Infof("volume %q for claim %q saved", volume.Name, claimToClaimKey(claim))
 
-			_, updateErr := ctrl.storeVolumeUpdate(newVol)
-			if updateErr != nil {
-				// We will get an "volume added" event soon, this is not a big error
-				glog.V(4).Infof("provisionClaimOperation [%s]: cannot update internal cache: %v", volume.Name, updateErr)
+				_, updateErr := ctrl.storeVolumeUpdate(newVol)
+				if updateErr != nil {
+					// We will get an "volume added" event soon, this is not a big error
+					glog.V(4).Infof("provisionClaimOperation [%s]: cannot update internal cache: %v", volume.Name, updateErr)
+				}
 			}
 			break
 		}