Merge pull request #69059 from caesarxuchao/unconditional-generation-increment

The metadata.generation of a Custom Resource is always incremented

staging/src/k8s.io/apiextensions-apiserver/pkg/registry/customresource/BUILD

@@ -64,6 +64,7 @@ go_test(
     srcs = [
         "etcd_test.go",
         "status_strategy_test.go",
+        "strategy_test.go",
     ],
     embed = [":go_default_library"],
     deps = [

staging/src/k8s.io/apiextensions-apiserver/pkg/registry/customresource/strategy.go

@@ -87,45 +87,46 @@ func (a customResourceStrategy) PrepareForCreate(ctx context.Context, obj runtim
 
 // PrepareForUpdate clears fields that are not allowed to be set by end users on update.
 func (a customResourceStrategy) PrepareForUpdate(ctx context.Context, obj, old runtime.Object) {
-	if !utilfeature.DefaultFeatureGate.Enabled(apiextensionsfeatures.CustomResourceSubresources) || a.status == nil {
-		return
-	}
-
 	newCustomResourceObject := obj.(*unstructured.Unstructured)
 	oldCustomResourceObject := old.(*unstructured.Unstructured)
 
 	newCustomResource := newCustomResourceObject.UnstructuredContent()
 	oldCustomResource := oldCustomResourceObject.UnstructuredContent()
 
-	// update is not allowed to set status
-	_, ok1 := newCustomResource["status"]
-	_, ok2 := oldCustomResource["status"]
-	switch {
-	case ok2:
-		newCustomResource["status"] = oldCustomResource["status"]
-	case ok1:
-		delete(newCustomResource, "status")
+	// If the /status subresource endpoint is installed, update is not allowed to set status.
+	if utilfeature.DefaultFeatureGate.Enabled(apiextensionsfeatures.CustomResourceSubresources) && a.status != nil {
+		_, ok1 := newCustomResource["status"]
+		_, ok2 := oldCustomResource["status"]
+		switch {
+		case ok2:
+			newCustomResource["status"] = oldCustomResource["status"]
+		case ok1:
+			delete(newCustomResource, "status")
+		}
 	}
 
-	// Any changes to the spec increment the generation number, any changes to the
-	// status should reflect the generation number of the corresponding object. We push
-	// the burden of managing the status onto the clients because we can't (in general)
-	// know here what version of spec the writer of the status has seen. It may seem like
-	// we can at first -- since obj contains spec -- but in the future we will probably make
-	// status its own object, and even if we don't, writes may be the result of a
-	// read-update-write loop, so the contents of spec may not actually be the spec that
-	// the CustomResource has *seen*.
-	newSpec, ok1 := newCustomResource["spec"]
-	oldSpec, ok2 := oldCustomResource["spec"]
-
-	// spec is changed, created or deleted
-	if (ok1 && ok2 && !apiequality.Semantic.DeepEqual(oldSpec, newSpec)) || (ok1 && !ok2) || (!ok1 && ok2) {
+	// except for the changes to `metadata`, any other changes
+	// cause the generation to increment.
+	newCopyContent := copyNonMetadata(newCustomResource)
+	oldCopyContent := copyNonMetadata(oldCustomResource)
+	if !apiequality.Semantic.DeepEqual(newCopyContent, oldCopyContent) {
 		oldAccessor, _ := meta.Accessor(oldCustomResourceObject)
 		newAccessor, _ := meta.Accessor(newCustomResourceObject)
 		newAccessor.SetGeneration(oldAccessor.GetGeneration() + 1)
 	}
 }
 
+func copyNonMetadata(original map[string]interface{}) map[string]interface{} {
+	ret := make(map[string]interface{})
+	for key, val := range original {
+		if key == "metadata" {
+			continue
+		}
+		ret[key] = val
+	}
+	return ret
+}
+
 // Validate validates a new CustomResource.
 func (a customResourceStrategy) Validate(ctx context.Context, obj runtime.Object) field.ErrorList {
 	return a.validator.Validate(ctx, obj, a.scale)

staging/src/k8s.io/apiextensions-apiserver/pkg/registry/customresource/strategy_test.go

@@ -0,0 +1,257 @@
+/*
+Copyright 2018 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package customresource
+
+import (
+	"context"
+	"reflect"
+	"testing"
+
+	"k8s.io/apiextensions-apiserver/pkg/apis/apiextensions"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+)
+
+func generation1() map[string]interface{} {
+	return map[string]interface{}{
+		"generation": int64(1),
+	}
+}
+
+func generation2() map[string]interface{} {
+	return map[string]interface{}{
+		"generation": int64(2),
+	}
+}
+
+func TestStrategyPrepareForUpdate(t *testing.T) {
+	strategy := customResourceStrategy{}
+	tcs := []struct {
+		name          string
+		old           *unstructured.Unstructured
+		obj           *unstructured.Unstructured
+		statusEnabled bool
+		expected      *unstructured.Unstructured
+	}{
+		{
+			name:          "/status is enabled, spec changes increment generation",
+			statusEnabled: true,
+			old: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": generation1(),
+					"spec":     "old",
+					"status":   "old",
+				},
+			},
+			obj: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": generation1(),
+					"spec":     "new",
+					"status":   "old",
+				},
+			},
+			expected: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": generation2(),
+					"spec":     "new",
+					"status":   "old",
+				},
+			},
+		},
+		{
+			name:          "/status is enabled, status changes do not increment generation, status changes removed",
+			statusEnabled: true,
+			old: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": generation1(),
+					"spec":     "old",
+					"status":   "old",
+				},
+			},
+			obj: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": generation1(),
+					"spec":     "old",
+					"status":   "new",
+				},
+			},
+			expected: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": generation1(),
+					"spec":     "old",
+					"status":   "old",
+				},
+			},
+		},
+		{
+			name:          "/status is enabled, metadata changes do not increment generation",
+			statusEnabled: true,
+			old: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": map[string]interface{}{
+						"generation": int64(1),
+						"other":      "old",
+					},
+					"spec":   "old",
+					"status": "old",
+				},
+			},
+			obj: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": map[string]interface{}{
+						"generation": int64(1),
+						"other":      "new",
+					},
+					"spec":   "old",
+					"status": "old",
+				},
+			},
+			expected: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": map[string]interface{}{
+						"generation": int64(1),
+						"other":      "new",
+					},
+					"spec":   "old",
+					"status": "old",
+				},
+			},
+		},
+		{
+			name:          "/status is disabled, spec changes increment generation",
+			statusEnabled: false,
+			old: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": generation1(),
+					"spec":     "old",
+					"status":   "old",
+				},
+			},
+			obj: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": generation1(),
+					"spec":     "new",
+					"status":   "old",
+				},
+			},
+			expected: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": generation2(),
+					"spec":     "new",
+					"status":   "old",
+				},
+			},
+		},
+		{
+			name:          "/status is disabled, status changes increment generation",
+			statusEnabled: false,
+			old: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": generation1(),
+					"spec":     "old",
+					"status":   "old",
+				},
+			},
+			obj: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": generation1(),
+					"spec":     "old",
+					"status":   "new",
+				},
+			},
+			expected: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": generation2(),
+					"spec":     "old",
+					"status":   "new",
+				},
+			},
+		},
+		{
+			name:          "/status is disabled, other top-level field changes increment generation",
+			statusEnabled: false,
+			old: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": generation1(),
+					"spec":     "old",
+					"image":    "old",
+					"status":   "old",
+				},
+			},
+			obj: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": generation1(),
+					"spec":     "old",
+					"image":    "new",
+					"status":   "old",
+				},
+			},
+			expected: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": generation2(),
+					"spec":     "old",
+					"image":    "new",
+					"status":   "old",
+				},
+			},
+		},
+		{
+			name:          "/status is disabled, metadata changes do not increment generation",
+			statusEnabled: false,
+			old: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": map[string]interface{}{
+						"generation": int64(1),
+						"other":      "old",
+					},
+					"spec":   "old",
+					"status": "old",
+				},
+			},
+			obj: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": map[string]interface{}{
+						"generation": int64(1),
+						"other":      "new",
+					},
+					"spec":   "old",
+					"status": "old",
+				},
+			},
+			expected: &unstructured.Unstructured{
+				Object: map[string]interface{}{
+					"metadata": map[string]interface{}{
+						"generation": int64(1),
+						"other":      "new",
+					},
+					"spec":   "old",
+					"status": "old",
+				},
+			},
+		},
+	}
+	for _, tc := range tcs {
+		if tc.statusEnabled {
+			strategy.status = &apiextensions.CustomResourceSubresourceStatus{}
+		} else {
+			strategy.status = nil
+		}
+		strategy.PrepareForUpdate(context.TODO(), tc.obj, tc.old)
+		if !reflect.DeepEqual(tc.obj, tc.expected) {
+			t.Errorf("test %q failed: expected: %v, got %v", tc.name, tc.expected, tc.obj)
+		}
+	}
+}