applyset: introduce abstraction over objects (#3077)

This lets us use typed and untyped objects.

Author: justinsb

porch/controllers/remoterootsync/pkg/applyset/applyset.go

@@ -16,12 +16,12 @@ package applyset
 
 import (
 	"context"
+	"encoding/json"
 	"fmt"
 	"sync"
 
 	"k8s.io/apimachinery/pkg/api/meta"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
-	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/client-go/dynamic"
@@ -75,7 +75,7 @@ func New(options Options) (*ApplySet, error) {
 
 // ReplaceAllObjects is used to replace the desired state of all the objects.
 // Any objects not specified are removed from the "desired" set.
-func (a *ApplySet) ReplaceAllObjects(objects []*unstructured.Unstructured) error {
+func (a *ApplySet) ReplaceAllObjects(objects []ApplyableObject) error {
 	a.mutex.Lock()
 	defer a.mutex.Unlock()
 
@@ -161,7 +161,7 @@ func (a *ApplySet) ApplyOnce(ctx context.Context) (*ApplyResults, error) {
 
 		name := obj.GetName()
 		ns := obj.GetNamespace()
-		gvk := obj.GetObjectKind().GroupVersionKind()
+		gvk := obj.GroupVersionKind()
 		nn := types.NamespacedName{Namespace: ns, Name: name}
 
 		restMapping, err := a.restMapper.RESTMapping(gvk.GroupKind(), gvk.Version)
@@ -190,7 +190,7 @@ func (a *ApplySet) ApplyOnce(ctx context.Context) (*ApplyResults, error) {
 			return nil, fmt.Errorf("unknown scope for gvk %s: %q", gvk, restMapping.Scope.Name())
 		}
 
-		j, err := obj.MarshalJSON()
+		j, err := json.Marshal(obj)
 		if err != nil {
 			// TODO: Differentiate between server-fixable vs client-fixable errors?
 			results.applyError(gvk, nn, fmt.Errorf("failed to marshal object to JSON: %w", err))

porch/controllers/remoterootsync/pkg/applyset/interfaces.go

@@ -0,0 +1,29 @@
+// Copyright 2022 Google LLC
+//
+// 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 applyset
+
+import (
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+)
+
+type ApplyableObject interface {
+	GroupVersionKind() schema.GroupVersionKind
+	GetNamespace() string
+	GetName() string
+
+	GetOwnerReferences() []metav1.OwnerReference
+	SetOwnerReferences([]metav1.OwnerReference)
+}

porch/controllers/remoterootsync/pkg/applyset/tracker.go

@@ -17,7 +17,6 @@ package applyset
 import (
 	"reflect"
 
-	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
 	"k8s.io/apimachinery/pkg/runtime"
 )
 
@@ -30,7 +29,7 @@ type objectTrackerList struct {
 
 // objectTracker tracks the state for a single object
 type objectTracker struct {
-	desired     *unstructured.Unstructured
+	desired     ApplyableObject
 	lastApplied runtime.Object
 
 	desiredIsApplied bool
@@ -47,7 +46,7 @@ type objectKey struct {
 }
 
 // computeKey returns the unique key for the object.
-func computeKey(u *unstructured.Unstructured) objectKey {
+func computeKey(u ApplyableObject) objectKey {
 	gvk := u.GroupVersionKind()
 	return objectKey{
 		Group:     gvk.Group,
@@ -61,7 +60,7 @@ func computeKey(u *unstructured.Unstructured) objectKey {
 // replaceAllObjects completely replaces the set of objects we are interested in.
 // We aim to reuse the current state where it carries over.
 // Because objectTrackerList is immutable, we copy-on-write to a new objectTrackerList and return it.
-func (l *objectTrackerList) replaceAllObjects(objects []*unstructured.Unstructured) *objectTrackerList {
+func (l *objectTrackerList) replaceAllObjects(objects []ApplyableObject) *objectTrackerList {
 	existingTrackers := make(map[objectKey]*objectTracker)
 	for i := range l.items {
 		tracker := &l.items[i]

porch/controllers/remoterootsync/pkg/controllers/remoterootsyncset/remoterootsync_controller.go

@@ -291,7 +291,7 @@ func (r *RemoteRootSyncSetReconciler) applyToClusterRef(ctx context.Context, sub
 }
 
 // BuildObjectsToApply config root sync
-func (r *RemoteRootSyncSetReconciler) BuildObjectsToApply(ctx context.Context, subject *api.RemoteRootSyncSet) ([]*unstructured.Unstructured, error) {
+func (r *RemoteRootSyncSetReconciler) BuildObjectsToApply(ctx context.Context, subject *api.RemoteRootSyncSet) ([]applyset.ApplyableObject, error) {
 	repository := subject.GetSpec().GetTemplate().GetOCI().GetRepository()
 	if repository == "" {
 		return nil, fmt.Errorf("spec.template.oci.repository is not set")
@@ -312,7 +312,7 @@ func (r *RemoteRootSyncSetReconciler) BuildObjectsToApply(ctx context.Context, s
 		return nil, err
 	}
 
-	var objects []*unstructured.Unstructured
+	var objects []applyset.ApplyableObject
 
 	for filePath, fileContents := range resources.Contents {
 		ext := path.Ext(filePath)