add "restart_deployment" method

Signed-off-by: Priyanka Saggu <priyankasaggu11929@gmail.com>

examples/deployment_crud.py

@@ -13,9 +13,16 @@
 # limitations under the License.
 
 """
-Creates, updates, and deletes a deployment using AppsV1Api.
+The example covers the following:
+    - Creation of a deployment using AppsV1Api
+    - update/patch to perform rolling restart on the deployment
+    - deletetion of the deployment
 """
 
+import datetime
+
+import pytz
+
 from kubernetes import client, config
 
 DEPLOYMENT_NAME = "nginx-deployment"
@@ -29,56 +36,110 @@ def create_deployment_object():
         ports=[client.V1ContainerPort(container_port=80)],
         resources=client.V1ResourceRequirements(
             requests={"cpu": "100m", "memory": "200Mi"},
-            limits={"cpu": "500m", "memory": "500Mi"}
-        )
+            limits={"cpu": "500m", "memory": "500Mi"},
+        ),
     )
+
     # Create and configurate a spec section
     template = client.V1PodTemplateSpec(
         metadata=client.V1ObjectMeta(labels={"app": "nginx"}),
-        spec=client.V1PodSpec(containers=[container]))
+        spec=client.V1PodSpec(containers=[container]),
+    )
+
     # Create the specification of deployment
     spec = client.V1DeploymentSpec(
-        replicas=3,
-        template=template,
-        selector={'matchLabels': {'app': 'nginx'}})
+        replicas=3, template=template, selector={
+            "matchLabels":
+            {"app": "nginx"}})
+
     # Instantiate the deployment object
     deployment = client.V1Deployment(
         api_version="apps/v1",
         kind="Deployment",
         metadata=client.V1ObjectMeta(name=DEPLOYMENT_NAME),
-        spec=spec)
+        spec=spec,
+    )
 
     return deployment
 
 
-def create_deployment(api_instance, deployment):
+def create_deployment(api, deployment):
     # Create deployement
-    api_response = api_instance.create_namespaced_deployment(
-        body=deployment,
-        namespace="default")
-    print("Deployment created. status='%s'" % str(api_response.status))
+    resp = api.create_namespaced_deployment(
+        body=deployment, namespace="default"
+    )
+
+    print("\n[INFO] deployment `nginx-deployment` created.\n")
+    print("%s\t%s\t\t\t%s\t%s" % ("NAMESPACE", "NAME", "REVISION", "IMAGE"))
+    print(
+        "%s\t\t%s\t%s\t\t%s\n"
+        % (
+            resp.metadata.namespace,
+            resp.metadata.name,
+            resp.metadata.generation,
+            resp.spec.template.spec.containers[0].image,
+        )
+    )
 
 
-def update_deployment(api_instance, deployment):
+def update_deployment(api, deployment):
     # Update container image
     deployment.spec.template.spec.containers[0].image = "nginx:1.16.0"
-    # Update the deployment
-    api_response = api_instance.patch_namespaced_deployment(
-        name=DEPLOYMENT_NAME,
-        namespace="default",
-        body=deployment)
-    print("Deployment updated. status='%s'" % str(api_response.status))
+
+    # patch the deployment
+    resp = api.patch_namespaced_deployment(
+        name=DEPLOYMENT_NAME, namespace="default", body=deployment
+    )
+
+    print("\n[INFO] deployment's container image updated.\n")
+    print("%s\t%s\t\t\t%s\t%s" % ("NAMESPACE", "NAME", "REVISION", "IMAGE"))
+    print(
+        "%s\t\t%s\t%s\t\t%s\n"
+        % (
+            resp.metadata.namespace,
+            resp.metadata.name,
+            resp.metadata.generation,
+            resp.spec.template.spec.containers[0].image,
+        )
+    )
 
 
-def delete_deployment(api_instance):
+def restart_deployment(api, deployment):
+    # update `spec.template.metadata` section
+    # to add `kubectl.kubernetes.io/restartedAt` annotation
+    deployment.spec.template.metadata.annotations = {
+        "kubectl.kubernetes.io/restartedAt": datetime.datetime.utcnow()
+        .replace(tzinfo=pytz.UTC)
+        .isoformat()
+    }
+
+    # patch the deployment
+    resp = api.patch_namespaced_deployment(
+        name=DEPLOYMENT_NAME, namespace="default", body=deployment
+    )
+
+    print("\n[INFO] deployment `nginx-deployment` restarted.\n")
+    print("%s\t\t\t%s\t%s" % ("NAME", "REVISION", "RESTARTED-AT"))
+    print(
+        "%s\t%s\t\t%s\n"
+        % (
+            resp.metadata.name,
+            resp.metadata.generation,
+            resp.spec.template.metadata.annotations,
+        )
+    )
+
+
+def delete_deployment(api):
     # Delete deployment
-    api_response = api_instance.delete_namespaced_deployment(
+    resp = api.delete_namespaced_deployment(
         name=DEPLOYMENT_NAME,
         namespace="default",
         body=client.V1DeleteOptions(
-            propagation_policy='Foreground',
-            grace_period_seconds=5))
-    print("Deployment deleted. status='%s'" % str(api_response.status))
+            propagation_policy="Foreground", grace_period_seconds=5
+        ),
+    )
+    print("\n[INFO] deployment `nginx-deployment` deleted.")
 
 
 def main():
@@ -101,8 +162,10 @@ def main():
 
     update_deployment(apps_v1, deployment)
 
+    restart_deployment(apps_v1, deployment)
+
     delete_deployment(apps_v1)
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     main()