refactor(kube-api-rewriter): rewrite ownerReferences for Lists

images/kube-api-proxy/pkg/rewriter/resource.go

@@ -155,14 +155,20 @@ func RestoreAPIVersionAndKind(rules *RewriteRules, obj []byte, origGroupName str
 }
 
 func RewriteOwnerReferences(rules *RewriteRules, obj []byte, action Action) ([]byte, error) {
-	ownerRefs := gjson.GetBytes(obj, "metadata.ownerReferences").Array()
-	if len(ownerRefs) == 0 {
+	ownerRefs := gjson.GetBytes(obj, "metadata.ownerReferences")
+	// Prevent adding empty ownereReferences to rewritten JSON.
+	if !ownerRefs.Exists() {
+		return obj, nil
+	}
+
+	ownerRefsArray := ownerRefs.Array()
+	if len(ownerRefsArray) == 0 {
 		return obj, nil
 	}
 
 	rwrOwnerRefs := []byte(`[]`)
 	rewritten := false
-	for _, ownerRef := range ownerRefs {
+	for _, ownerRef := range ownerRefsArray {
 		kind := ownerRef.Get("kind").String()
 		if action == Restore {
 			kind = rules.RestoreKind(kind)
@@ -213,14 +219,20 @@ func RewriteOwnerReferences(rules *RewriteRules, obj []byte, action Action) ([]b
 
 // RenameOwnerReferences renames kind and apiVersion to send request to server.
 func RenameOwnerReferences(rules *RewriteRules, obj []byte) ([]byte, error) {
-	ownerRefs := gjson.GetBytes(obj, "metadata.ownerReferences").Array()
-	if len(ownerRefs) == 0 {
+	ownerRefs := gjson.GetBytes(obj, "metadata.ownerReferences")
+	// Prevent adding empty ownereReferences to rewritten JSON.
+	if !ownerRefs.Exists() {
+		return obj, nil
+	}
+
+	ownerRefsArray := ownerRefs.Array()
+	if len(ownerRefsArray) == 0 {
 		return obj, nil
 	}
 
 	rwrOwnerRefs := []byte(`[]`)
 	var err error
-	for _, ownerRef := range ownerRefs {
+	for _, ownerRef := range ownerRefsArray {
 		apiVersion := ownerRef.Get("apiVersion").String()
 		kind := ownerRef.Get("kind").String()
 

images/kube-api-proxy/pkg/rewriter/rule_rewriter.go

@@ -270,9 +270,8 @@ func (rw *RuleBasedRewriter) RewriteJSONPayload(targetReq *TargetRequest, obj []
 		rwrBytes, err = RewriteServiceMonitorOrList(rw.Rules, obj, action)
 
 	default:
-		if targetReq.IsCore() {
-			rwrBytes, err = RewriteOwnerReferences(rw.Rules, obj, action)
-		} else {
+		// TODO replace !IsCore with new method rw.Rules.IsKnownKind()
+		if !targetReq.IsCore() {
 			rwrBytes, err = RewriteCustomResourceOrList(rw.Rules, obj, action)
 		}
 	}
@@ -281,21 +280,15 @@ func (rw *RuleBasedRewriter) RewriteJSONPayload(targetReq *TargetRequest, obj []
 		return obj, err
 	}
 
-	rwrBytes, err = RewriteResourceOrList2(rwrBytes, func(singleObj []byte) ([]byte, error) {
-		return RewriteMetadata(rw.Rules, singleObj, action)
-	})
-	if err != nil {
-		return obj, err
-	}
-
-	if shouldRewriteOwnerReferences(kind) {
-		rwrBytes, err = RewriteOwnerReferences(rw.Rules, rwrBytes, action)
+	// Always rewrite metadata: labels, annotations, finalizers, ownerReferences.
+	// TODO: add rewriter for managedFields.
+	return RewriteResourceOrList2(rwrBytes, func(singleObj []byte) ([]byte, error) {
+		singleObj, err := RewriteMetadata(rw.Rules, singleObj, action)
 		if err != nil {
-			return obj, err
+			return nil, err
 		}
-	}
-
-	return rwrBytes, nil
+		return RewriteOwnerReferences(rw.Rules, singleObj, action)
+	})
 }
 
 // RewritePatch rewrites patches for some known objects.