add a cronjob crud example

examples/cronjob_crud.py

@@ -0,0 +1,130 @@
+#!/usr/bin/python3
+# -*- coding:utf-8 -*-
+
+import json
+import time
+
+from kubernetes import client, config
+
+config.load_kube_config()
+
+
+def create_namespaced_cron_job(namespace='default', body=None):
+    cronjob_json = body
+    if body is None:
+        print('body is required!')
+        exit(0)
+    name = body['metadata']['name']
+    if judge_crontab_exists(namespace, name):
+        print(f'{name} exists, please do not repeat!')
+    else:
+        v1 = client.BatchV1beta1Api()
+        ret = v1.create_namespaced_cron_job(namespace=namespace, body=cronjob_json, pretty=True,
+                                            _preload_content=False, async_req=False)
+        ret_dict = json.loads(ret.data)
+        print(f'create succeed\n{json.dumps(ret_dict)}')
+
+
+def delete_namespaced_cron_job(namespace='default', name=None):
+    if name is None:
+        print('name is required!')
+        exit(0)
+    if not judge_crontab_exists(namespace, name):
+        print(f"{name} doesn't exists, please enter a new one!")
+    else:
+        v1 = client.BatchV1beta1Api()
+        ret = v1.delete_namespaced_cron_job(name=name, namespace=namespace, _preload_content=False, async_req=False)
+        ret_dict = json.loads(ret.data)
+        print(f'delete succeed\n{json.dumps(ret_dict)}')
+
+
+def patch_namespaced_cron_job(namespace='default', body=None):
+    cronjob_json = body
+    if body is None:
+        print('body is required!')
+        exit(0)
+    name = body['metadata']['name']
+    if judge_crontab_exists(namespace, name):
+        v1 = client.BatchV1beta1Api()
+        ret = v1.patch_namespaced_cron_job(name=name, namespace=namespace, body=cronjob_json,
+                                           _preload_content=False, async_req=False)
+        ret_dict = json.loads(ret.data)
+        print(f'patch succeed\n{json.dumps(ret_dict)}')
+    else:
+        print(f"{name} doesn't exists, please enter a new one!")
+
+
+def get_cronjob_list(namespace='default'):
+    v1 = client.BatchV1beta1Api()
+    ret = v1.list_namespaced_cron_job(namespace=namespace, pretty=True, _preload_content=False)
+    cron_job_list = json.loads(ret.data)
+    print(f'cronjob number={len(cron_job_list["items"])}')
+    # for cron in cron_job_list['items']:
+    #     print(json.dumps(cron))
+    return cron_job_list["items"]
+
+
+def judge_crontab_exists(namespace, name):
+    cron_job_list = get_cronjob_list(namespace)
+    for cron_job in cron_job_list:
+        if name == cron_job['metadata']['name']:
+            return True
+    return False
+
+
+def get_cronjob_body(namespace, name, command):
+    body = {
+        "apiVersion": "batch/v1beta1",
+        "kind": "CronJob",
+        "metadata": {
+            "name": name,
+            "namespace": namespace
+        },
+        "spec": {
+            "schedule": "*/1 * * * *",
+            "concurrencyPolicy": "Allow",
+            "suspend": False,
+            "jobTemplate": {
+                "spec": {
+                    "template": {
+                        "spec": {
+                            "containers": [
+                                {
+                                    "name": name,
+                                    "image": "busybox:1.35",
+                                    "command": command
+                                }
+                            ],
+                            "restartPolicy": "Never"
+                        }
+                    }
+                }
+            },
+            "successfulJobsHistoryLimit": 3,
+            "failedJobsHistoryLimit": 1
+        }
+    }
+    return body
+
+
+if __name__ == '__main__':
+    # get
+    cronjob_list = get_cronjob_list()
+
+    # delete
+    delete_namespaced_cron_job('default', 'hostname')
+    time.sleep(2)
+
+    # create
+    container_command = [
+        "/bin/sh",
+        "-c",
+        "date; echo Hello from the Kubernetes cluster; hostname"
+    ]
+    hostname_json = get_cronjob_body('default', 'hostname', container_command)
+    create_namespaced_cron_job('default', hostname_json)
+
+    # update
+    container_command[2] = "date; echo this is patch; hostname"
+    hostname_json = get_cronjob_body('default', 'hostname', container_command)
+    patch_namespaced_cron_job('default', hostname_json)