refactor: review rework

Author: at88mph

examples/examples-release-latest/src/main/java/io/kubernetes/client/examples/MetricsExample.java

@@ -64,5 +64,22 @@ public static void main(String[] args) throws IOException, ApiException {
         System.out.println();
       }
     }
+
+      for (PodMetrics item : metrics.getPodMetrics("default", "foo=bar").getItems()) {
+          System.out.println(item.getMetadata().getName());
+          System.out.println("------------------------------");
+          if (item.getContainers() == null) {
+              continue;
+          }
+          for (ContainerMetrics container : item.getContainers()) {
+              System.out.println(container.getName());
+              System.out.println("-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-");
+              for (String key : container.getUsage().keySet()) {
+                  System.out.println("\t" + key);
+                  System.out.println("\t" + container.getUsage().get(key));
+              }
+              System.out.println();
+          }
+      }
   }
 }

util/src/main/java/io/kubernetes/client/Metrics.java

@@ -20,6 +20,7 @@
 import io.kubernetes.client.openapi.ApiException;
 import io.kubernetes.client.openapi.Configuration;
 import io.kubernetes.client.util.generic.GenericKubernetesApi;
+import io.kubernetes.client.util.generic.KubernetesApiResponse;
 import io.kubernetes.client.util.generic.options.ListOptions;
 
 import javax.annotation.Nullable;
@@ -91,8 +92,15 @@ public PodMetricsList getPodMetrics(String namespace, @Nullable String labelSele
     GenericKubernetesApi<PodMetrics, PodMetricsList> metricsClient =
             new GenericKubernetesApi<>(
                     PodMetrics.class, PodMetricsList.class, Metrics.API_GROUP, Metrics.API_VERSION, Metrics.PODS, apiClient);
-    final ListOptions listOptions = new ListOptions();
-    listOptions.setLabelSelector(labelSelector);
-    return metricsClient.list(namespace, listOptions).throwsApiException().getObject();
+    final KubernetesApiResponse<PodMetricsList> response;
+    if (labelSelector == null || labelSelector.trim().isEmpty()) {
+        response = metricsClient.list(namespace);
+    } else {
+        final ListOptions listOptions = new ListOptions();
+        listOptions.setLabelSelector(labelSelector);
+        response = metricsClient.list(namespace, listOptions);
+    }
+
+    return response.throwsApiException().getObject();
   }
 }

util/src/test/java/io/kubernetes/client/MetricsTest.java

@@ -14,8 +14,6 @@
 
 import static com.github.tomakehurst.wiremock.client.WireMock.*;
 import static com.github.tomakehurst.wiremock.core.WireMockConfiguration.options;
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.failBecauseExceptionWasNotThrown;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import com.github.tomakehurst.wiremock.junit5.WireMockExtension;
@@ -53,20 +51,6 @@ void getPodMetricsThrowsAPIExceptionWhenServerReturnsError() {
       assertThrows(ApiException.class, () -> metrics.getPodMetrics(namespace));
   }
 
-  @Test
-  void getPodMetricsWithLabelSelectorThrowsAPIExceptionWhenServerReturnsError() {
-    String namespace = "default";
-    Metrics metrics = new Metrics(client);
-    apiServer.stubFor(
-        get(urlPathMatching("^/apis/metrics.k8s.io/v1beta1/namespaces/" + namespace + "/pods.*"))
-            .willReturn(
-                aResponse()
-                    .withStatus(503)
-                    .withHeader("Content-Type", "text/plain")
-                    .withBody("Service Unavailable")));
-    assertThrows(ApiException.class, () -> metrics.getPodMetrics(namespace, "foo=bar"));
-  }
-
   @Test
   void getNodeMetricsThrowsAPIExceptionWhenServerReturnsError() {
     Metrics metrics = new Metrics(client);