fix: do not replace namespaces (#524)

When doing `kubectl replace`, namespaces should not be affected. Fixes
argoproj/argo-cd#12810 and argoproj/argo-cd#12539.

Signed-off-by: Blake Pettersson <[email protected]>

Author: blakepettersson

pkg/sync/sync_context.go

@@ -915,8 +915,10 @@ func (sc *syncContext) applyObject(t *syncTask, dryRun, force, validate bool) (c
 	serverSideApply := sc.serverSideApply || resourceutil.HasAnnotationOption(t.targetObj, common.AnnotationSyncOptions, common.SyncOptionServerSideApply)
 	if shouldReplace {
 		if t.liveObj != nil {
-			// Avoid using `kubectl replace` for CRDs since 'replace' might recreate resource and so delete all CRD instances
-			if kube.IsCRD(t.targetObj) {
+			// Avoid using `kubectl replace` for CRDs since 'replace' might recreate resource and so delete all CRD instances.
+			// The same thing applies for namespaces, which would delete the namespace as well as everything within it,
+			// so we want to avoid using `kubectl replace` in that case as well.
+			if kube.IsCRD(t.targetObj) || t.targetObj.GetKind() == kubeutil.NamespaceKind {
 				update := t.targetObj.DeepCopy()
 				update.SetResourceVersion(t.liveObj.GetResourceVersion())
 				_, err = sc.resourceOps.UpdateResource(context.TODO(), update, dryRunStrategy)

pkg/sync/sync_context_test.go

@@ -784,6 +784,7 @@ func TestSync_ServerSideApply(t *testing.T) {
 		{"NoAnnotation", NewPod(), NewPod(), "apply", false, "managerA"},
 		{"ServerSideApplyAnnotationIsSet", withServerSideApplyAnnotation(NewPod()), NewPod(), "apply", true, "managerB"},
 		{"ServerSideApplyAndReplaceAnnotationsAreSet", withReplaceAndServerSideApplyAnnotations(NewPod()), NewPod(), "replace", false, ""},
+		{"ServerSideApplyAndReplaceAnnotationsAreSetNamespace", withReplaceAndServerSideApplyAnnotations(NewNamespace()), NewNamespace(), "update", false, ""},
 		{"LiveObjectMissing", withReplaceAnnotation(NewPod()), nil, "create", false, ""},
 	}