Add validation check for projected pod names length (#1120)

CHANGELOG/CHANGELOG-1.12.md

@@ -15,3 +15,4 @@ When cutting a new release, update the `unreleased` heading to the tag being gen
 
 ## unreleased
 
+- [ENHANCEMENT] [#1115](https://github.com/k8ssandra/k8ssandra-operator/issues/1115) Add a validation check for the projected pod names length

apis/k8ssandra/v1alpha1/k8ssandracluster_webhook.go

@@ -88,6 +88,27 @@ func (r *K8ssandraCluster) validateK8ssandraCluster() error {
 		}
 	}
 
+	if err := r.validateStatefulsetNameSize(); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func (r *K8ssandraCluster) validateStatefulsetNameSize() error {
+	for _, dc := range r.Spec.Cassandra.Datacenters {
+		if len(dc.Racks) > 0 {
+			for _, rack := range dc.Racks {
+				if len(r.SanitizedName()+"-"+dc.CassDcName()+"-"+rack.Name+"-sts-") > 60 {
+					return fmt.Errorf("the name of the statefulset for rack %s in DC %s is too long", rack.Name, dc.CassDcName())
+				}
+			}
+		} else {
+			if len(r.SanitizedName()+"-"+dc.CassDcName()+"-default-sts-") > 60 {
+				return fmt.Errorf("the name of the statefulset for DC %s is too long", dc.CassDcName())
+			}
+		}
+	}
 	return nil
 }
 
@@ -148,6 +169,10 @@ func (r *K8ssandraCluster) ValidateUpdate(old runtime.Object) error {
 	// TODO StorageConfig can not be modified (not Cluster or DC level) in existing datacenters
 	// TODO Racks can only be added and only at the end of the list - no other operation is allowed to racks
 
+	if err := r.validateStatefulsetNameSize(); err != nil {
+		return err
+	}
+
 	return nil
 }
 

apis/k8ssandra/v1alpha1/k8ssandracluster_webhook_test.go

@@ -144,6 +144,7 @@ func TestWebhook(t *testing.T) {
 	t.Run("StorageConfigValidation", testStorageConfigValidation)
 	t.Run("NumTokensValidation", testNumTokens)
 	t.Run("NumTokensValidationInUpdate", testNumTokensInUpdate)
+	t.Run("StsNameTooLong", testStsNameTooLong)
 }
 
 func testContextValidation(t *testing.T) {
@@ -337,6 +338,15 @@ func testNumTokens(t *testing.T) {
 	required.Error(errorOnValidate, "expected error when changing the value of num tokens while also changing other field values")
 }
 
+func testStsNameTooLong(t *testing.T) {
+	required := require.New(t)
+	createNamespace(required, "too-long-namespace")
+	cluster := createMinimalClusterObj("create-very-long-cluster-name-which-will-overflow-our-limit", "too-long-namespace")
+
+	err := k8sClient.Create(ctx, cluster)
+	required.Error(err)
+}
+
 func createNamespace(require *require.Assertions, namespace string) {
 	ns := &corev1.Namespace{
 		ObjectMeta: metav1.ObjectMeta{
@@ -386,6 +396,9 @@ func createMinimalClusterObj(name, namespace string) *K8ssandraCluster {
 				},
 				Datacenters: []CassandraDatacenterTemplate{
 					{
+						Meta: EmbeddedObjectMeta{
+							Name: "dc1",
+						},
 						K8sContext: "envtest",
 						Size:       1,
 					},