Support node label update.

pkg/registry/minion/healthy_registry.go

@@ -62,6 +62,10 @@ func (r *HealthyRegistry) CreateMinion(ctx api.Context, minion *api.Minion) erro
 	return r.delegate.CreateMinion(ctx, minion)
 }
 
+func (r *HealthyRegistry) UpdateMinion(ctx api.Context, minion *api.Minion) error {
+	return r.delegate.UpdateMinion(ctx, minion)
+}
+
 func (r *HealthyRegistry) ListMinions(ctx api.Context) (currentMinions *api.MinionList, err error) {
 	result := &api.MinionList{}
 	list, err := r.delegate.ListMinions(ctx)

pkg/registry/minion/registry.go

@@ -22,6 +22,7 @@ import "github.com/GoogleCloudPlatform/kubernetes/pkg/api"
 type Registry interface {
 	ListMinions(ctx api.Context) (*api.MinionList, error)
 	CreateMinion(ctx api.Context, minion *api.Minion) error
+	UpdateMinion(ctx api.Context, minion *api.Minion) error
 	GetMinion(ctx api.Context, minionID string) (*api.Minion, error)
 	DeleteMinion(ctx api.Context, minionID string) error
 }

pkg/registry/minion/rest.go

@@ -100,8 +100,23 @@ func (rs *REST) New() runtime.Object {
 	return &api.Minion{}
 }
 
-func (rs *REST) Update(ctx api.Context, minion runtime.Object) (<-chan apiserver.RESTResult, error) {
-	return nil, fmt.Errorf("Minions can only be created (inserted) and deleted.")
+func (rs *REST) Update(ctx api.Context, obj runtime.Object) (<-chan apiserver.RESTResult, error) {
+	minion, ok := obj.(*api.Minion)
+	if !ok {
+		return nil, fmt.Errorf("not a minion: %#v", obj)
+	}
+	if errs := validation.ValidateMinion(minion); len(errs) > 0 {
+		return nil, kerrors.NewInvalid("minion", minion.Name, errs)
+	}
+	return apiserver.MakeAsync(func() (runtime.Object, error) {
+		err := rs.registry.UpdateMinion(ctx, minion)
+		if err != nil {
+			return nil, err
+		}
+		// TODO: GetMinion will health check the minion, but we shouldn't require the minion to be
+		// running for updating labels.
+		return rs.registry.GetMinion(ctx, minion.Name)
+	}), nil
 }
 
 func (rs *REST) toApiMinion(name string) *api.Minion {

pkg/registry/minion/rest_test.go

@@ -17,6 +17,7 @@ limitations under the License.
 package minion
 
 import (
+	"reflect"
 	"testing"
 
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
@@ -119,6 +120,49 @@ func contains(nodes *api.MinionList, nodeID string) bool {
 	return false
 }
 
+func TestMinionRegistryUpdate(t *testing.T) {
+	minionRegistry := registrytest.NewMinionRegistry([]string{}, api.NodeResources{})
+	ms := NewREST(minionRegistry)
+
+	ctx := api.NewContext()
+
+	expected_labels := map[string]string{"foo": "bar"}
+	c, err := ms.Create(ctx, &api.Minion{
+		ObjectMeta: api.ObjectMeta{Name: "m1"},
+		Labels:     expected_labels,
+	})
+	if err != nil {
+		t.Errorf("insert failed")
+	}
+	result := <-c
+
+	created, ok := result.Object.(*api.Minion)
+	if !ok || created.Name != "m1" {
+		t.Errorf("insert return value was weird: %#v", result)
+	}
+	if !reflect.DeepEqual(expected_labels, created.Labels) {
+		t.Errorf("unexpected labels: %#v", created.Labels)
+	}
+
+	update := new(api.Minion)
+	*update = *created
+	update_labels := map[string]string{"bar": "foo"}
+	update.Labels = update_labels
+
+	c, err = ms.Update(ctx, update)
+	if err != nil {
+		t.Errorf("update failed")
+	}
+	result = <-c
+	updated, ok := result.Object.(*api.Minion)
+	if !ok || updated.Name != "m1" {
+		t.Errorf("update return value was weird: %#v", result)
+	}
+	if !reflect.DeepEqual(update_labels, updated.Labels) {
+		t.Errorf("unexpected labels: %#v", updated.Labels)
+	}
+}
+
 func TestMinionStorageValidatesCreate(t *testing.T) {
 	storage := NewREST(registrytest.NewMinionRegistry([]string{"foo", "bar"}, api.NodeResources{}))
 	ctx := api.NewContext()