Merge pull request #7407 from brendandburns/recovery2

pkg/kubectl/cmd/rollingupdate.go

@@ -26,6 +26,7 @@ import (
 	"time"
 
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
+	apierrors "github.com/GoogleCloudPlatform/kubernetes/pkg/api/errors"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/client"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/fields"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/kubectl"
@@ -155,44 +156,59 @@ func RunRollingUpdate(f *cmdutil.Factory, out io.Writer, cmd *cobra.Command, arg
 		}
 	}
 	if len(image) != 0 {
+		var newName string
 		var err error
-		// load the old RC into the "new" RC
-		if newRc, err = client.ReplicationControllers(cmdNamespace).Get(oldName); err != nil {
-			return err
-		}
-
-		if len(newRc.Spec.Template.Spec.Containers) > 1 {
-			// TODO: support multi-container image update.
-			return errors.New("Image update is not supported for multi-container pods")
-		}
-		if len(newRc.Spec.Template.Spec.Containers) == 0 {
-			return cmdutil.UsageError(cmd, "Pod has no containers! (%v)", newRc)
-		}
-		newRc.Spec.Template.Spec.Containers[0].Image = image
 
-		newHash, err := hashObject(newRc, client.Codec)
-		if err != nil {
-			return err
-		}
-
-		var newName string
 		if len(args) >= 2 {
 			newName = args[1]
 		} else {
-			keepOldName = true
-			newName = fmt.Sprintf("%s-%s", newRc.Name, newHash)
+			newName, _ = kubectl.GetNextControllerAnnotation(oldRc)
 		}
-		newRc.Name = newName
 
-		newRc.Spec.Selector[deploymentKey] = newHash
-		newRc.Spec.Template.Labels[deploymentKey] = newHash
-		// Clear resource version after hashing so that identical updates get different hashes.
-		newRc.ResourceVersion = ""
+		if len(newName) > 0 {
+			newRc, err = client.ReplicationControllers(cmdNamespace).Get(newName)
+			if err != nil && !apierrors.IsNotFound(err) {
+				return err
+			}
+			fmt.Fprint(out, "Found existing update in progress (%s), resuming.\n", newName)
+		}
+		if newRc == nil {
+			// load the old RC into the "new" RC
+			if newRc, err = client.ReplicationControllers(cmdNamespace).Get(oldName); err != nil {
+				return err
+			}
 
-		if _, found := oldRc.Spec.Selector[deploymentKey]; !found {
-			if err := addDeploymentKeyToReplicationController(oldRc, client, deploymentKey, cmdNamespace, out); err != nil {
+			if len(newRc.Spec.Template.Spec.Containers) > 1 {
+				// TODO: support multi-container image update.
+				return errors.New("Image update is not supported for multi-container pods")
+			}
+			if len(newRc.Spec.Template.Spec.Containers) == 0 {
+				return cmdutil.UsageError(cmd, "Pod has no containers! (%v)", newRc)
+			}
+			newRc.Spec.Template.Spec.Containers[0].Image = image
+
+			newHash, err := hashObject(newRc, client.Codec)
+			if err != nil {
 				return err
 			}
+
+			if len(newName) == 0 {
+				keepOldName = true
+				newName = fmt.Sprintf("%s-%s", newRc.Name, newHash)
+			}
+			newRc.Name = newName
+
+			newRc.Spec.Selector[deploymentKey] = newHash
+			newRc.Spec.Template.Labels[deploymentKey] = newHash
+			// Clear resource version after hashing so that identical updates get different hashes.
+			newRc.ResourceVersion = ""
+
+			kubectl.SetNextControllerAnnotation(oldRc, newName)
+			if _, found := oldRc.Spec.Selector[deploymentKey]; !found {
+				if err := addDeploymentKeyToReplicationController(oldRc, client, deploymentKey, cmdNamespace, out); err != nil {
+					return err
+				}
+			}
 		}
 	}
 	newName := newRc.Name

pkg/kubectl/rolling_updater.go

@@ -82,8 +82,21 @@ func NewRollingUpdater(namespace string, c RollingUpdaterClient) *RollingUpdater
 const (
 	sourceIdAnnotation        = kubectlAnnotationPrefix + "update-source-id"
 	desiredReplicasAnnotation = kubectlAnnotationPrefix + "desired-replicas"
+	nextControllerAnnotation  = kubectlAnnotationPrefix + "next-controller-id"
 )
 
+func GetNextControllerAnnotation(rc *api.ReplicationController) (string, bool) {
+	res, found := rc.Annotations[nextControllerAnnotation]
+	return res, found
+}
+
+func SetNextControllerAnnotation(rc *api.ReplicationController, name string) {
+	if rc.Annotations == nil {
+		rc.Annotations = map[string]string{}
+	}
+	rc.Annotations[nextControllerAnnotation] = name
+}
+
 // Update all pods for a ReplicationController (oldRc) by creating a new
 // controller (newRc) with 0 replicas, and synchronously resizing oldRc,newRc
 // by 1 until oldRc has 0 replicas and newRc has the original # of desired