Make updates atomic from the client side.

cmd/kubecfg/kubecfg.go

@@ -29,6 +29,7 @@ import (
 	"text/template"
 	"time"
 
+	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
 	kube_client "github.com/GoogleCloudPlatform/kubernetes/pkg/client"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/kubecfg"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
@@ -202,6 +203,7 @@ func executeAPIRequest(method string, s *kube_client.Client) bool {
 	validStorage := checkStorage(storage)
 	verb := ""
 	setBody := false
+	var version uint64
 	switch method {
 	case "get":
 		verb = "GET"
@@ -225,6 +227,15 @@ func executeAPIRequest(method string, s *kube_client.Client) bool {
 			glog.Fatalf("usage: kubecfg [OPTIONS] %s <%s>", method, prettyWireStorage())
 		}
 	case "update":
+		obj, err := s.Verb("GET").Path(path).Do().Get()
+		if err != nil {
+			glog.Fatalf("error obtaining resource version for update: %v", err)
+		}
+		jsonBase, err := api.FindJSONBase(obj)
+		if err != nil {
+			glog.Fatalf("error finding json base for update: %v", err)
+		}
+		version = jsonBase.ResourceVersion()
 		verb = "PUT"
 		setBody = true
 		if !validStorage || !hasSuffix {
@@ -238,7 +249,25 @@ func executeAPIRequest(method string, s *kube_client.Client) bool {
 		Path(path).
 		ParseSelector(*selector)
 	if setBody {
-		r.Body(readConfig(storage))
+		if version != 0 {
+			data := readConfig(storage)
+			obj, err := api.Decode(data)
+			if err != nil {
+				glog.Fatalf("error setting resource version: %v", err)
+			}
+			jsonBase, err := api.FindJSONBase(obj)
+			if err != nil {
+				glog.Fatalf("error setting resource version: %v", err)
+			}
+			jsonBase.SetResourceVersion(version)
+			data, err = api.Encode(obj)
+			if err != nil {
+				glog.Fatalf("error setting resource version: %v", err)
+			}
+			r.Body(data)
+		} else {
+			r.Body(readConfig(storage))
+		}
 	}
 	result := r.Do()
 	obj, err := result.Get()

pkg/client/client.go

@@ -192,12 +192,10 @@ func (c *Client) CreatePod(pod api.Pod) (result api.Pod, err error) {
 
 // UpdatePod takes the representation of a pod to update.  Returns the server's representation of the pod, and an error, if it occurs
 func (c *Client) UpdatePod(pod api.Pod) (result api.Pod, err error) {
-	var prev api.Pod
-	err = c.Get().Path("pod").Path(pod.ID).Do().Into(&prev)
-	if err != nil {
+	if pod.ResourceVersion == 0 {
+		err = fmt.Errorf("invalid update object, missing resource version: %v", pod)
 		return
 	}
-	pod.ResourceVersion = prev.ResourceVersion
 	err = c.Put().Path("pods").Path(pod.ID).Body(pod).Do().Into(&result)
 	return
 }
@@ -222,12 +220,10 @@ func (c *Client) CreateReplicationController(controller api.ReplicationControlle
 
 // UpdateReplicationController updates an existing replication controller
 func (c *Client) UpdateReplicationController(controller api.ReplicationController) (result api.ReplicationController, err error) {
-	var prev api.ReplicationController
-	err = c.Get().Path("replicationControllers").Path(controller.ID).Do().Into(&prev)
-	if err != nil {
+	if controller.ResourceVersion == 0 {
+		err = fmt.Errorf("invalid update object, missing resource version: %v", controller)
 		return
 	}
-	controller.ResourceVersion = prev.ResourceVersion
 	err = c.Put().Path("replicationControllers").Path(controller.ID).Body(controller).Do().Into(&result)
 	return
 }
@@ -251,12 +247,10 @@ func (c *Client) CreateService(svc api.Service) (result api.Service, err error)
 
 // UpdateService updates an existing service.
 func (c *Client) UpdateService(svc api.Service) (result api.Service, err error) {
-	var prev api.Service
-	err = c.Get().Path("services").Path(svc.ID).Do().Into(&prev)
-	if err != nil {
+	if svc.ResourceVersion == 0 {
+		err = fmt.Errorf("invalid update object, missing resource version: %v", svc)
 		return
 	}
-	svc.ResourceVersion = prev.ResourceVersion
 	err = c.Put().Path("services").Path(svc.ID).Body(svc).Do().Into(&result)
 	return
 }

pkg/client/client_test.go

@@ -154,7 +154,7 @@ func TestCreatePod(t *testing.T) {
 
 func TestUpdatePod(t *testing.T) {
 	requestPod := api.Pod{
-		JSONBase: api.JSONBase{ID: "foo"},
+		JSONBase: api.JSONBase{ID: "foo", ResourceVersion: 1},
 		CurrentState: api.PodState{
 			Status: "Foobar",
 		},
@@ -219,7 +219,7 @@ func TestGetController(t *testing.T) {
 
 func TestUpdateController(t *testing.T) {
 	requestController := api.ReplicationController{
-		JSONBase: api.JSONBase{ID: "foo"},
+		JSONBase: api.JSONBase{ID: "foo", ResourceVersion: 1},
 	}
 	c := &testClient{
 		Request: testRequest{Method: "PUT", Path: "/replicationControllers/foo"},
@@ -388,11 +388,12 @@ func TestCreateService(t *testing.T) {
 }
 
 func TestUpdateService(t *testing.T) {
+	svc := api.Service{JSONBase: api.JSONBase{ID: "service-1", ResourceVersion: 1}}
 	c := &testClient{
-		Request:  testRequest{Method: "PUT", Path: "/services/service-1", Body: &api.Service{JSONBase: api.JSONBase{ID: "service-1"}}},
-		Response: Response{StatusCode: 200, Body: &api.Service{JSONBase: api.JSONBase{ID: "service-1"}}},
+		Request:  testRequest{Method: "PUT", Path: "/services/service-1", Body: &svc},
+		Response: Response{StatusCode: 200, Body: &svc},
 	}
-	response, err := c.Setup().UpdateService(api.Service{JSONBase: api.JSONBase{ID: "service-1"}})
+	response, err := c.Setup().UpdateService(svc)
 	c.Validate(t, &response, err)
 }