Allow update without resource version

pkg/tools/etcd_helper.go

@@ -207,7 +207,7 @@ func (h *EtcdHelper) decodeNodeList(nodes []*etcd.Node, slicePtr interface{}) er
 			}
 			if h.Versioner != nil {
 				// being unable to set the version does not prevent the object from being extracted
-				_ = h.Versioner.UpdateObject(obj.Interface().(runtime.Object), node)
+				_ = h.Versioner.UpdateObject(obj.Interface().(runtime.Object), node.Expiration, node.ModifiedIndex)
 			}
 			v.Set(reflect.Append(v, obj.Elem()))
 			if node.ModifiedIndex != 0 {
@@ -377,7 +377,7 @@ func (h *EtcdHelper) extractObj(response *etcd.Response, inErr error, objPtr run
 	body = node.Value
 	err = h.Codec.DecodeInto([]byte(body), objPtr)
 	if h.Versioner != nil {
-		_ = h.Versioner.UpdateObject(objPtr, node)
+		_ = h.Versioner.UpdateObject(objPtr, node.Expiration, node.ModifiedIndex)
 		// being unable to set the version does not prevent the object from being extracted
 	}
 	return body, node, err
@@ -492,6 +492,11 @@ type ResponseMeta struct {
 	// zero or negative in some cases (objects may be expired after the requested
 	// expiration time due to server lag).
 	TTL int64
+	// Expiration is the time at which the node that contained the returned object will expire and be deleted.
+	// This can be nil if there is no expiration time set for the node.
+	Expiration *time.Time
+	// The resource version of the node that contained the returned object.
+	ResourceVersion uint64
 }
 
 // Pass an EtcdUpdateFunc to EtcdHelper.GuaranteedUpdate to make an etcd update that is guaranteed to succeed.
@@ -525,7 +530,7 @@ func SimpleUpdate(fn SimpleEtcdUpdateFunc) EtcdUpdateFunc {
 //	cur.Counter++
 //
 //	// Return the modified object. Return an error to stop iterating. Return a uint64 to alter
-//  // the TTL on the object, or nil to keep it the same value.
+//      // the TTL on the object, or nil to keep it the same value.
 //	return cur, nil, nil
 // })
 //
@@ -545,8 +550,12 @@ func (h *EtcdHelper) GuaranteedUpdate(key string, ptrToType runtime.Object, igno
 		meta := ResponseMeta{}
 		if node != nil {
 			meta.TTL = node.TTL
+			if node.Expiration != nil {
+				meta.Expiration = node.Expiration
+			}
+			meta.ResourceVersion = node.ModifiedIndex
 		}
-
+		// Get the object to be written by calling tryUpdate.
 		ret, newTTL, err := tryUpdate(obj, meta)
 		if err != nil {
 			return err
@@ -589,9 +598,11 @@ func (h *EtcdHelper) GuaranteedUpdate(key string, ptrToType runtime.Object, igno
 		}
 
 		startTime := time.Now()
+		// Swap origBody with data, if origBody is the latest etcd data.
 		response, err := h.Client.CompareAndSwap(key, string(data), ttl, origBody, index)
 		recordEtcdRequestLatency("compareAndSwap", getTypeName(ptrToType), startTime)
 		if IsEtcdTestFailed(err) {
+			// Try again.
 			continue
 		}
 		_, _, err = h.extractObj(response, err, ptrToType, false, false)

pkg/tools/etcd_helper_watch.go

@@ -270,7 +270,7 @@ func (w *etcdWatcher) decodeObject(node *etcd.Node) (runtime.Object, error) {
 
 	// ensure resource version is set on the object we load from etcd
 	if w.versioner != nil {
-		if err := w.versioner.UpdateObject(obj, node); err != nil {
+		if err := w.versioner.UpdateObject(obj, node.Expiration, node.ModifiedIndex); err != nil {
 			glog.Errorf("failure to version api object (%d) %#v: %v", node.ModifiedIndex, obj, err)
 		}
 	}

pkg/tools/etcd_object.go

@@ -18,12 +18,11 @@ package tools
 
 import (
 	"strconv"
+	"time"
 
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/runtime"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
-
-	"github.com/coreos/go-etcd/etcd"
 )
 
 // APIObjectVersioner implements versioning and extracting etcd node information
@@ -31,18 +30,17 @@ import (
 type APIObjectVersioner struct{}
 
 // UpdateObject implements EtcdVersioner
-func (a APIObjectVersioner) UpdateObject(obj runtime.Object, node *etcd.Node) error {
+func (a APIObjectVersioner) UpdateObject(obj runtime.Object, expiration *time.Time, resourceVersion uint64) error {
 	objectMeta, err := api.ObjectMetaFor(obj)
 	if err != nil {
 		return err
 	}
-	if ttl := node.Expiration; ttl != nil {
-		objectMeta.DeletionTimestamp = &util.Time{*node.Expiration}
+	if expiration != nil {
+		objectMeta.DeletionTimestamp = &util.Time{*expiration}
 	}
-	version := node.ModifiedIndex
 	versionString := ""
-	if version != 0 {
-		versionString = strconv.FormatUint(version, 10)
+	if resourceVersion != 0 {
+		versionString = strconv.FormatUint(resourceVersion, 10)
 	}
 	objectMeta.ResourceVersion = versionString
 	return nil

pkg/tools/etcd_object_test.go

@@ -22,7 +22,6 @@ import (
 
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/api"
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/util"
-	"github.com/coreos/go-etcd/etcd"
 )
 
 func TestObjectVersioner(t *testing.T) {
@@ -34,7 +33,7 @@ func TestObjectVersioner(t *testing.T) {
 		t.Errorf("unexpected version: %d %v", ver, err)
 	}
 	obj := &TestResource{ObjectMeta: api.ObjectMeta{ResourceVersion: "a"}}
-	if err := v.UpdateObject(obj, &etcd.Node{ModifiedIndex: 5}); err != nil {
+	if err := v.UpdateObject(obj, nil, 5); err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
 	if obj.ResourceVersion != "5" || obj.DeletionTimestamp != nil {
@@ -42,7 +41,7 @@ func TestObjectVersioner(t *testing.T) {
 	}
 	now := util.Time{time.Now()}
 	obj = &TestResource{ObjectMeta: api.ObjectMeta{ResourceVersion: "a"}}
-	if err := v.UpdateObject(obj, &etcd.Node{ModifiedIndex: 5, Expiration: &now.Time}); err != nil {
+	if err := v.UpdateObject(obj, &now.Time, 5); err != nil {
 		t.Fatalf("unexpected error: %v", err)
 	}
 	if obj.ResourceVersion != "5" || *obj.DeletionTimestamp != now {

pkg/tools/interfaces.go

@@ -19,6 +19,7 @@ package tools
 import (
 	"github.com/GoogleCloudPlatform/kubernetes/pkg/runtime"
 	"github.com/coreos/go-etcd/etcd"
+	"time"
 )
 
 const (
@@ -66,7 +67,7 @@ type EtcdVersioner interface {
 	// UpdateObject sets etcd storage metadata into an API object. Returns an error if the object
 	// cannot be updated correctly. May return nil if the requested object does not need metadata
 	// from etcd.
-	UpdateObject(obj runtime.Object, node *etcd.Node) error
+	UpdateObject(obj runtime.Object, expiration *time.Time, resourceVersion uint64) error
 	// UpdateList sets the resource version into an API list object. Returns an error if the object
 	// cannot be updated correctly. May return nil if the requested object does not need metadata
 	// from etcd.