apiextensions: set 'metadata.generation: 1' during read from etcd if not set

staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/customresource_handler.go

@@ -1020,6 +1020,7 @@ func (t crdConversionRESTOptionsGetter) GetRESTOptions(resource schema.GroupReso
 		d := schemaCoercingDecoder{delegate: ret.StorageConfig.Codec, validator: unstructuredSchemaCoercer{
 			// drop invalid fields while decoding old CRs (before we haven't had any ObjectMeta validation)
 			dropInvalidMetadata:   true,
+			repairGeneration:      true,
 			structuralSchemas:     t.structuralSchemas,
 			structuralSchemaGK:    t.structuralSchemaGK,
 			preserveUnknownFields: t.preserveUnknownFields,
@@ -1120,6 +1121,7 @@ func (v schemaCoercingConverter) ConvertFieldLabel(gvk schema.GroupVersionKind,
 // - generic pruning of unknown fields following a structural schema.
 type unstructuredSchemaCoercer struct {
 	dropInvalidMetadata bool
+	repairGeneration    bool
 
 	structuralSchemas     map[string]*structuralschema.Structural
 	structuralSchemaGK    schema.GroupKind
@@ -1154,6 +1156,10 @@ func (v *unstructuredSchemaCoercer) apply(u *unstructured.Unstructured) error {
 		if err := schemaobjectmeta.Coerce(nil, u.Object, v.structuralSchemas[gv.Version], false, v.dropInvalidMetadata); err != nil {
 			return err
 		}
+		// fixup missing generation in very old CRs
+		if v.repairGeneration && objectMeta.Generation == 0 {
+			objectMeta.Generation = 1
+		}
 	}
 
 	// restore meta fields, starting clean

staging/src/k8s.io/apiextensions-apiserver/pkg/apiserver/schema/objectmeta/coerce_test.go

@@ -167,6 +167,7 @@ func TestGetObjectMetaNils(t *testing.T) {
 			"apiVersion": "v1",
 			"metadata": map[string]interface{}{
 				"generateName": nil,
+				"generation":   nil,
 				"labels": map[string]interface{}{
 					"foo": nil,
 				},
@@ -179,7 +180,10 @@ func TestGetObjectMetaNils(t *testing.T) {
 		t.Fatal(err)
 	}
 	if o.GenerateName != "" {
-		t.Errorf("expected null json value to be read as \"\" string, but got: %q", o.GenerateName)
+		t.Errorf("expected null json generateName value to be read as \"\" string, but got: %q", o.GenerateName)
+	}
+	if o.Generation != 0 {
+		t.Errorf("expected null json generation value to be read as zero, but got: %q", o.Generation)
 	}
 	if got, expected := o.Labels, map[string]string{"foo": ""}; !reflect.DeepEqual(got, expected) {
 		t.Errorf("unexpected labels, expected=%#v, got=%#v", expected, got)
@@ -198,6 +202,9 @@ func TestGetObjectMetaNils(t *testing.T) {
 	if got, expected := o.GenerateName, pod.ObjectMeta.GenerateName; got != expected {
 		t.Errorf("expected generatedName to be %q, got %q", expected, got)
 	}
+	if got, expected := o.Generation, pod.ObjectMeta.Generation; got != expected {
+		t.Errorf("expected generation to be %q, got %q", expected, got)
+	}
 	if got, expected := o.Labels, pod.ObjectMeta.Labels; !reflect.DeepEqual(got, expected) {
 		t.Errorf("expected labels to be %v, got %v", expected, got)
 	}

staging/src/k8s.io/apiextensions-apiserver/test/integration/objectmeta_test.go

@@ -62,6 +62,7 @@ func TestPostInvalidObjectMeta(t *testing.T) {
 
 	obj := fixtures.NewNoxuInstance("default", "foo")
 	unstructured.SetNestedField(obj.UnstructuredContent(), int64(42), "metadata", "unknown")
+	unstructured.SetNestedField(obj.UnstructuredContent(), nil, "metadata", "generation")
 	unstructured.SetNestedField(obj.UnstructuredContent(), map[string]interface{}{"foo": int64(42), "bar": "abc"}, "metadata", "labels")
 	_, err = instantiateCustomResource(t, obj, noxuResourceClient, noxuDefinition)
 	if err == nil {
@@ -86,6 +87,14 @@ func TestPostInvalidObjectMeta(t *testing.T) {
 	} else if found {
 		t.Errorf("unexpected metadata.unknown=%#v: expected this to be pruned", unknown)
 	}
+
+	if generation, found, err := unstructured.NestedInt64(obj.UnstructuredContent(), "metadata", "generation"); err != nil {
+		t.Errorf("unexpected error getting metadata.generation: %v", err)
+	} else if !found {
+		t.Errorf("expected metadata.generation=1: got: %d", generation)
+	} else if generation != 1 {
+		t.Errorf("unexpected metadata.generation=%d: expected this to be set to 1", generation)
+	}
 }
 
 func TestInvalidObjectMetaInStorage(t *testing.T) {
@@ -150,6 +159,8 @@ func TestInvalidObjectMetaInStorage(t *testing.T) {
 
 	original := fixtures.NewNoxuInstance("default", "foo")
 	unstructured.SetNestedField(original.UnstructuredContent(), int64(42), "metadata", "unknown")
+	unstructured.SetNestedField(original.UnstructuredContent(), nil, "metadata", "generation")
+
 	unstructured.SetNestedField(original.UnstructuredContent(), map[string]interface{}{"foo": int64(42), "bar": "abc"}, "metadata", "annotations")
 	unstructured.SetNestedField(original.UnstructuredContent(), map[string]interface{}{"invalid": "x y"}, "metadata", "labels")
 	unstructured.SetNestedField(original.UnstructuredContent(), int64(42), "embedded", "metadata", "unknown")
@@ -193,6 +204,16 @@ func TestInvalidObjectMetaInStorage(t *testing.T) {
 		t.Errorf("Unexpected to find embedded.metadata.unknown=%#v", unknown)
 	}
 
+	t.Logf("Checking that metadata.generation=1")
+
+	if generation, found, err := unstructured.NestedInt64(obj.UnstructuredContent(), "metadata", "generation"); err != nil {
+		t.Errorf("unexpected error getting metadata.generation: %v", err)
+	} else if !found {
+		t.Errorf("expected metadata.generation=1: got: %d", generation)
+	} else if generation != 1 {
+		t.Errorf("unexpected metadata.generation=%d: expected this to be set to 1", generation)
+	}
+
 	t.Logf("Checking that ObjectMeta is pruned from wrongly-typed annotations")
 
 	if annotations, found, err := unstructured.NestedStringMap(obj.UnstructuredContent(), "metadata", "annotations"); err != nil {