Add deployment rollout restart example

Author: Dmitriy Dubson

examples/examples-release-15/src/main/java/io/kubernetes/client/examples/DeployRolloutRestartExample.java

@@ -0,0 +1,140 @@
+/*
+Copyright 2022 The Kubernetes Authors.
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+http://www.apache.org/licenses/LICENSE-2.0
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+package io.kubernetes.client.examples;
+
+import io.kubernetes.client.custom.V1Patch;
+import io.kubernetes.client.openapi.ApiClient;
+import io.kubernetes.client.openapi.ApiException;
+import io.kubernetes.client.openapi.Configuration;
+import io.kubernetes.client.openapi.apis.AppsV1Api;
+import io.kubernetes.client.openapi.models.V1Container;
+import io.kubernetes.client.openapi.models.V1Deployment;
+import io.kubernetes.client.openapi.models.V1DeploymentBuilder;
+import io.kubernetes.client.openapi.models.V1DeploymentSpec;
+import io.kubernetes.client.openapi.models.V1LabelSelector;
+import io.kubernetes.client.openapi.models.V1ObjectMeta;
+import io.kubernetes.client.openapi.models.V1PodSpec;
+import io.kubernetes.client.openapi.models.V1PodTemplateSpec;
+import io.kubernetes.client.util.Config;
+import io.kubernetes.client.util.PatchUtils;
+import io.kubernetes.client.util.wait.Wait;
+import java.io.IOException;
+import java.time.Duration;
+import java.time.LocalDateTime;
+import java.util.Collections;
+
+public class DeployRolloutRestartExample {
+  public static void main(String[] args) throws IOException, ApiException {
+    ApiClient client = Config.defaultClient();
+    Configuration.setDefaultApiClient(client);
+    AppsV1Api appsV1Api = new AppsV1Api(client);
+
+    String deploymentName = "example-nginx";
+    String imageName = "nginx:1.21.6";
+    String namespace = "default";
+
+    // Create an example deployment
+    V1DeploymentBuilder deploymentBuilder =
+        new V1DeploymentBuilder()
+            .withApiVersion("apps/v1")
+            .withKind("Deployment")
+            .withMetadata(new V1ObjectMeta().name(deploymentName).namespace(namespace))
+            .withSpec(
+                new V1DeploymentSpec()
+                    .replicas(1)
+                    .selector(new V1LabelSelector().putMatchLabelsItem("name", deploymentName))
+                    .template(
+                        new V1PodTemplateSpec()
+                            .metadata(new V1ObjectMeta().putLabelsItem("name", deploymentName))
+                            .spec(
+                                new V1PodSpec()
+                                    .containers(
+                                        Collections.singletonList(
+                                            new V1Container()
+                                                .name(deploymentName)
+                                                .image(imageName))))));
+    appsV1Api.createNamespacedDeployment(
+        namespace, deploymentBuilder.build(), null, null, null, null);
+
+    // Wait until example deployment is ready
+    Wait.poll(
+        Duration.ofSeconds(3),
+        Duration.ofSeconds(60),
+        () -> {
+          try {
+            System.out.println("Waiting until example deployment is ready...");
+            return appsV1Api
+                    .readNamespacedDeployment(deploymentName, namespace, null)
+                    .getStatus()
+                    .getReadyReplicas()
+                > 0;
+          } catch (ApiException e) {
+            e.printStackTrace();
+            return false;
+          }
+        });
+    System.out.println("Created example deployment!");
+
+    // Trigger a rollout restart of the example deployment
+    V1Deployment runningDeployment =
+        appsV1Api.readNamespacedDeployment(deploymentName, namespace, null);
+
+    // Explicitly set "restartedAt" annotation with current date/time to trigger rollout when patch
+    // is applied
+    runningDeployment
+        .getSpec()
+        .getTemplate()
+        .getMetadata()
+        .putAnnotationsItem("kubectl.kubernetes.io/restartedAt", LocalDateTime.now().toString());
+    try {
+      String deploymentJson = client.getJSON().serialize(runningDeployment);
+
+      PatchUtils.patch(
+          V1Deployment.class,
+          () ->
+              appsV1Api.patchNamespacedDeploymentCall(
+                  deploymentName,
+                  namespace,
+                  new V1Patch(deploymentJson),
+                  null,
+                  null,
+                  "kubectl-rollout",
+                  null,
+                  null,
+                  null),
+          V1Patch.PATCH_FORMAT_STRATEGIC_MERGE_PATCH,
+          client);
+
+      // Wait until deployment has stabilized after rollout restart
+      Wait.poll(
+          Duration.ofSeconds(3),
+          Duration.ofSeconds(60),
+          () -> {
+            try {
+              System.out.println("Waiting until example deployment restarted successfully...");
+              return appsV1Api
+                      .readNamespacedDeployment(deploymentName, namespace, null)
+                      .getStatus()
+                      .getReadyReplicas()
+                  > 0;
+            } catch (ApiException e) {
+              e.printStackTrace();
+              return false;
+            }
+          });
+      System.out.println("Example deployment restarted successfully!");
+    } catch (ApiException e) {
+      e.printStackTrace();
+    }
+  }
+}