Add deployment rollout restart example

Author: Dmitriy Dubson

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

@@ -0,0 +1,97 @@
+/*
+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 java.io.IOException;
+import java.time.Duration;
+import java.time.LocalDateTime;
+import java.util.Collections;
+
+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;
+
+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:latest";
+		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();
+		}
+	}
+}