Get namespace from cached cilent config

Author: honnix

operator-framework-core/src/main/java/io/javaoperatorsdk/operator/LeaderElectionManager.java

@@ -39,14 +39,15 @@ public LeaderElectionManager(ControllerManager controllerManager) {
   public void init(LeaderElectionConfiguration config, KubernetesClient client) {
     this.identity = identity(config);
     final var leaseNamespace =
-        config.getLeaseNamespace().or(LeaderElectionManager::tryNamespaceFromPath);
-    if (leaseNamespace.isEmpty()) {
+        config.getLeaseNamespace().orElseGet(
+            () -> ConfigurationServiceProvider.instance().getClientConfiguration().getNamespace());
+    if (leaseNamespace == null) {
       final var message =
           "Lease namespace is not set and cannot be inferred. Leader election cannot continue.";
       log.error(message);
       throw new IllegalArgumentException(message);
     }
-    final var lock = new LeaseLock(leaseNamespace.orElseThrow(), config.getLeaseName(), identity);
+    final var lock = new LeaseLock(leaseNamespace, config.getLeaseName(), identity);
     // releaseOnCancel is not used in the underlying implementation
     leaderElector =
         new LeaderElectorBuilder(

operator-framework-core/src/test/java/io/javaoperatorsdk/operator/LeaderElectionManagerTest.java

@@ -12,6 +12,7 @@
 import io.fabric8.kubernetes.client.KubernetesClient;
 import io.javaoperatorsdk.operator.api.config.LeaderElectionConfiguration;
 
+import static io.fabric8.kubernetes.client.Config.KUBERNETES_AUTH_TRYKUBECONFIG_SYSTEM_PROPERTY;
 import static io.fabric8.kubernetes.client.Config.KUBERNETES_NAMESPACE_FILE;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.api.Assertions.assertTrue;
@@ -33,6 +34,7 @@ void setUp() {
   @AfterEach
   void tearDown() {
     System.getProperties().remove(KUBERNETES_NAMESPACE_FILE);
+    System.getProperties().remove(KUBERNETES_AUTH_TRYKUBECONFIG_SYSTEM_PROPERTY);
   }
 
   @Test
@@ -47,6 +49,7 @@ void testInitInferLeaseNamespace(@TempDir Path tempDir) throws IOException {
     var namespacePath = tempDir.resolve("namespace");
     Files.writeString(namespacePath, namespace);
 
+    System.setProperty(KUBERNETES_AUTH_TRYKUBECONFIG_SYSTEM_PROPERTY, "false");
     System.setProperty(KUBERNETES_NAMESPACE_FILE, namespacePath.toString());
 
     leaderElectionManager.init(new LeaderElectionConfiguration("test"), kubernetesClient);
@@ -55,6 +58,15 @@ void testInitInferLeaseNamespace(@TempDir Path tempDir) throws IOException {
 
   @Test
   void testFailedToInitInferLeaseNamespace() {
+    System.setProperty(KUBERNETES_AUTH_TRYKUBECONFIG_SYSTEM_PROPERTY, "false");
+    assertThrows(
+        IllegalArgumentException.class,
+        () -> leaderElectionManager.init(new LeaderElectionConfiguration("test"),
+            kubernetesClient));
+  }
+
+  @Test
+  void testFailedToInitInferLeaseNamespaceProbablyUsingKubeConfig() {
     assertThrows(
         IllegalArgumentException.class,
         () -> leaderElectionManager.init(new LeaderElectionConfiguration("test"),