Add Backup warning for inclusion of NS managed by ArgoCD

Signed-off-by: Shubham Pampattiwar <[email protected]>

add changelog file

Signed-off-by: Shubham Pampattiwar <[email protected]>

run make update

Signed-off-by: Shubham Pampattiwar <[email protected]>

re-position import

Signed-off-by: Shubham Pampattiwar <[email protected]>

update argo cd label comment

Signed-off-by: Shubham Pampattiwar <[email protected]>

add nil check for backupRequest.Spec.IncludedNamespaces

Signed-off-by: Shubham Pampattiwar <[email protected]>

minor fix

Signed-off-by: Shubham Pampattiwar <[email protected]>

fix edge cases

Signed-off-by: Shubham Pampattiwar <[email protected]>

add gh issue link in code comments

Signed-off-by: Shubham Pampattiwar <[email protected]>

changelogs/unreleased/8257-shubham-pampattiwar

@@ -0,0 +1 @@
+Add Backup warning for inclusion of NS managed by ArgoCD

pkg/backup/backup.go

@@ -30,6 +30,7 @@ import (
 
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
+	corev1api "k8s.io/api/core/v1"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	"k8s.io/apimachinery/pkg/api/meta"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
@@ -71,6 +72,9 @@ const BackupVersion = 1
 // BackupFormatVersion is the current backup version for Velero, including major, minor, and patch.
 const BackupFormatVersion = "1.1.0"
 
+// ArgoCD managed by namespace label key
+const ArgoCDManagedByNamespaceLabel = "argocd.argoproj.io/managed-by"
+
 // Backupper performs backups.
 type Backupper interface {
 	// Backup takes a backup using the specification in the velerov1api.Backup and writes backup and log data
@@ -244,6 +248,18 @@ func (kb *kubernetesBackupper) BackupWithResolvers(
 	log.Infof("Including namespaces: %s", backupRequest.NamespaceIncludesExcludes.IncludesString())
 	log.Infof("Excluding namespaces: %s", backupRequest.NamespaceIncludesExcludes.ExcludesString())
 
+	// check if there are any namespaces included in the backup which are managed by argoCD
+	// We will check for the existence of a ArgoCD label in the includedNamespaces and add a warning
+	// so that users are at least aware about the existence of argoCD managed ns in their backup
+	// Related Issue: https://github.com/vmware-tanzu/velero/issues/7905
+	if len(backupRequest.Spec.IncludedNamespaces) > 0 {
+		nsManagedByArgoCD := getNamespacesManagedByArgoCD(kb.kbClient, backupRequest.Spec.IncludedNamespaces, log)
+
+		if len(nsManagedByArgoCD) > 0 {
+			log.Warnf("backup operation may encounter complications and potentially produce undesirable results due to the inclusion of namespaces %v managed by ArgoCD in the backup.", nsManagedByArgoCD)
+		}
+	}
+
 	if collections.UseOldResourceFilters(backupRequest.Spec) {
 		backupRequest.ResourceIncludesExcludes = collections.GetGlobalResourceIncludesExcludes(kb.discoveryHelper, log,
 			backupRequest.Spec.IncludedResources,
@@ -1107,3 +1123,26 @@ func putVolumeInfos(
 
 	return backupStore.PutBackupVolumeInfos(backupName, backupVolumeInfoBuf)
 }
+
+func getNamespacesManagedByArgoCD(kbClient kbclient.Client, includedNamespaces []string, log logrus.FieldLogger) []string {
+	var nsManagedByArgoCD []string
+
+	for _, nsName := range includedNamespaces {
+		ns := corev1api.Namespace{}
+		if err := kbClient.Get(context.Background(), kbclient.ObjectKey{Name: nsName}, &ns); err != nil {
+			// check for only those ns that exist and are included in backup
+			// here we ignore cases like "" or "*" specified under includedNamespaces
+			if apierrors.IsNotFound(err) {
+				continue
+			}
+			log.WithError(err).Errorf("error getting namespace %s", nsName)
+			continue
+		}
+
+		nsLabels := ns.GetLabels()
+		if len(nsLabels[ArgoCDManagedByNamespaceLabel]) > 0 {
+			nsManagedByArgoCD = append(nsManagedByArgoCD, nsName)
+		}
+	}
+	return nsManagedByArgoCD
+}