Add RemainingItemCount to ListMeta

Kubernetes-commit: 58c18309a84f9e0fe05b92c202616e4ecf8062f7

pkg/storage/cacher/cacher.go

@@ -604,7 +604,7 @@ func (c *Cacher) GetToList(ctx context.Context, key string, resourceVersion stri
 		}
 	}
 	if c.versioner != nil {
-		if err := c.versioner.UpdateList(listObj, readResourceVersion, ""); err != nil {
+		if err := c.versioner.UpdateList(listObj, readResourceVersion, "", 0); err != nil {
 			return err
 		}
 	}
@@ -679,7 +679,7 @@ func (c *Cacher) List(ctx context.Context, key string, resourceVersion string, p
 	}
 	trace.Step(fmt.Sprintf("Filtered %d items", listVal.Len()))
 	if c.versioner != nil {
-		if err := c.versioner.UpdateList(listObj, readResourceVersion, ""); err != nil {
+		if err := c.versioner.UpdateList(listObj, readResourceVersion, "", 0); err != nil {
 			return err
 		}
 	}

pkg/storage/cacher/cacher_whitebox_test.go

@@ -217,13 +217,14 @@ type testVersioner struct{}
 func (testVersioner) UpdateObject(obj runtime.Object, resourceVersion uint64) error {
 	return meta.NewAccessor().SetResourceVersion(obj, strconv.FormatUint(resourceVersion, 10))
 }
-func (testVersioner) UpdateList(obj runtime.Object, resourceVersion uint64, continueValue string) error {
+func (testVersioner) UpdateList(obj runtime.Object, resourceVersion uint64, continueValue string, count int64) error {
 	listAccessor, err := meta.ListAccessor(obj)
 	if err != nil || listAccessor == nil {
 		return err
 	}
 	listAccessor.SetResourceVersion(strconv.FormatUint(resourceVersion, 10))
 	listAccessor.SetContinue(continueValue)
+	listAccessor.SetRemainingItemCount(count)
 	return nil
 }
 func (testVersioner) PrepareObjectForStorage(obj runtime.Object) error {

pkg/storage/etcd/api_object_versioner.go

@@ -44,7 +44,7 @@ func (a APIObjectVersioner) UpdateObject(obj runtime.Object, resourceVersion uin
 }
 
 // UpdateList implements Versioner
-func (a APIObjectVersioner) UpdateList(obj runtime.Object, resourceVersion uint64, nextKey string) error {
+func (a APIObjectVersioner) UpdateList(obj runtime.Object, resourceVersion uint64, nextKey string, count int64) error {
 	listAccessor, err := meta.ListAccessor(obj)
 	if err != nil || listAccessor == nil {
 		return err
@@ -55,6 +55,7 @@ func (a APIObjectVersioner) UpdateList(obj runtime.Object, resourceVersion uint6
 	}
 	listAccessor.SetResourceVersion(versionString)
 	listAccessor.SetContinue(nextKey)
+	listAccessor.SetRemainingItemCount(count)
 	return nil
 }
 

pkg/storage/etcd3/store.go

@@ -413,7 +413,7 @@ func (s *store) GetToList(ctx context.Context, key string, resourceVersion strin
 		}
 	}
 	// update version with cluster level revision
-	return s.versioner.UpdateList(listObj, uint64(getResp.Header.Revision), "")
+	return s.versioner.UpdateList(listObj, uint64(getResp.Header.Revision), "", 0)
 }
 
 func (s *store) Count(key string) (int64, error) {
@@ -576,9 +576,10 @@ func (s *store) List(ctx context.Context, key, resourceVersion string, pred stor
 	// loop until we have filled the requested limit from etcd or there are no more results
 	var lastKey []byte
 	var hasMore bool
+	var getResp *clientv3.GetResponse
 	for {
 		startTime := time.Now()
-		getResp, err := s.client.KV.Get(ctx, key, options...)
+		getResp, err = s.client.KV.Get(ctx, key, options...)
 		metrics.RecordEtcdRequestLatency("list", getTypeName(listPtr), startTime)
 		if err != nil {
 			return interpretListError(err, len(pred.Continue) > 0, continueKey, keyPrefix)
@@ -639,11 +640,17 @@ func (s *store) List(ctx context.Context, key, resourceVersion string, pred stor
 		if err != nil {
 			return err
 		}
-		return s.versioner.UpdateList(listObj, uint64(returnedRV), next)
+		remainingItemCount := getResp.Count - pred.Limit
+		// getResp.Count counts in objects that do not match the pred.
+		// Instead of returning inaccurate count, return 0.
+		if !pred.Empty() {
+			remainingItemCount = 0
+		}
+		return s.versioner.UpdateList(listObj, uint64(returnedRV), next, remainingItemCount)
 	}
 
 	// no continuation
-	return s.versioner.UpdateList(listObj, uint64(returnedRV), "")
+	return s.versioner.UpdateList(listObj, uint64(returnedRV), "", 0)
 }
 
 // growSlice takes a slice value and grows its capacity up

pkg/storage/etcd3/store_test.go

@@ -825,14 +825,15 @@ func TestList(t *testing.T) {
 	}
 
 	tests := []struct {
-		name           string
+		name                       string
-		disablePaging  bool
+		disablePaging              bool
-		rv             string
+		rv                         string
-		prefix         string
+		prefix                     string
-		pred           storage.SelectionPredicate
+		pred                       storage.SelectionPredicate
-		expectedOut    []*example.Pod
+		expectedOut                []*example.Pod
-		expectContinue bool
+		expectContinue             bool
-		expectError    bool
+		expectedRemainingItemCount int64
+		expectError                bool
 	}{
 		{
 			name:        "rejects invalid resource version",
@@ -882,8 +883,9 @@ func TestList(t *testing.T) {
 				Field: fields.Everything(),
 				Limit: 1,
 			},
-			expectedOut:    []*example.Pod{preset[1].storedObj},
+			expectedOut:                []*example.Pod{preset[1].storedObj},
-			expectContinue: true,
+			expectContinue:             true,
+			expectedRemainingItemCount: 1,
 		},
 		{
 			name:          "test List with limit when paging disabled",
@@ -1061,6 +1063,9 @@ func TestList(t *testing.T) {
 			t.Errorf("(%s): length of list want=%d, got=%d", tt.name, len(tt.expectedOut), len(out.Items))
 			continue
 		}
+		if e, a := tt.expectedRemainingItemCount, out.ListMeta.RemainingItemCount; e != a {
+			t.Errorf("(%s): remainingItemCount want=%d, got=%d", tt.name, e, a)
+		}
 		for j, wantPod := range tt.expectedOut {
 			getPod := &out.Items[j]
 			if !reflect.DeepEqual(wantPod, getPod) {

pkg/storage/interfaces.go

@@ -40,10 +40,12 @@ type Versioner interface {
 	// from database.
 	UpdateObject(obj runtime.Object, 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
+	// cannot be updated correctly. May return nil if the requested object does not need metadata from
-	// from database. continueValue is optional and indicates that more results are available if
+	// database. continueValue is optional and indicates that more results are available if the client
-	// the client passes that value to the server in a subsequent call.
+	// passes that value to the server in a subsequent call. remainingItemCount indicates the number
-	UpdateList(obj runtime.Object, resourceVersion uint64, continueValue string) error
+	// of remaining objects if the list is partial. The remainingItemCount field is omitted during
+	// serialization if it is set to 0.
+	UpdateList(obj runtime.Object, resourceVersion uint64, continueValue string, remainingItemCount int64) error
 	// PrepareObjectForStorage should set SelfLink and ResourceVersion to the empty value. Should
 	// return an error if the specified object cannot be updated.
 	PrepareObjectForStorage(obj runtime.Object) error