Add helper function SecretOperatorVolumeSourceBuilder::with_kerberos_service_name (#568)

## Description

Needed for stackabletech/hdfs-operator#334 and stackabletech/hdfs-operator#178

Author: sbernauer

CHANGELOG.md

@@ -6,9 +6,11 @@ All notable changes to this project will be documented in this file.
 
 ### Added
 
-- Helper Method to add a restart_policy to PodBuilder([#565]).
+- Helper function to add a restart_policy to PodBuilder ([#565]).
+- Add helper function `SecretOperatorVolumeSourceBuilder::with_kerberos_service_name` ([#568]).
 
 [#565]: https://github.com/stackabletech/operator-rs/pull/565
+[#568]: https://github.com/stackabletech/operator-rs/pull/568
 
 ## [0.37.0] - 2023-03-06
 

src/builder/pod/volume.rs

@@ -265,13 +265,15 @@ impl VolumeMountBuilder {
 pub struct SecretOperatorVolumeSourceBuilder {
     secret_class: String,
     scopes: Vec<SecretOperatorVolumeScope>,
+    kerberos_service_names: Vec<String>,
 }
 
 impl SecretOperatorVolumeSourceBuilder {
     pub fn new(secret_class: impl Into<String>) -> Self {
         Self {
             secret_class: secret_class.into(),
             scopes: Vec::new(),
+            kerberos_service_names: Vec::new(),
         }
     }
 
@@ -291,6 +293,11 @@ impl SecretOperatorVolumeSourceBuilder {
         self
     }
 
+    pub fn with_kerberos_service_name(&mut self, name: impl Into<String>) -> &mut Self {
+        self.kerberos_service_names.push(name.into());
+        self
+    }
+
     pub fn build(&self) -> EphemeralVolumeSource {
         let mut attrs = BTreeMap::from([(
             "secrets.stackable.tech/class".to_string(),
@@ -315,6 +322,13 @@ impl SecretOperatorVolumeSourceBuilder {
             attrs.insert("secrets.stackable.tech/scope".to_string(), scopes);
         }
 
+        if !self.kerberos_service_names.is_empty() {
+            attrs.insert(
+                "secrets.stackable.tech/kerberos.service.names".to_string(),
+                self.kerberos_service_names.join(","),
+            );
+        }
+
         EphemeralVolumeSource {
             volume_claim_template: Some(PersistentVolumeClaimTemplate {
                 metadata: Some(ObjectMetaBuilder::new().annotations(attrs).build()),