python3的kubernetes api 使用

 一、認證

github：https://github.com/kubernetes-client/python

1、kubeconfig文件認證

首先引入SDK支持庫。然后將 ~/.kube 的config文件的內容復制到本地目錄，保存為文件kubeconfig.yaml，然后運行下面的python代碼。

#使用
from kubernetes import client, config
config.kube_config.load_kube_config(config_file="/root/.kube/config")

二、API調用

1、列出資源信息

from kubernetes import client, config
config.kube_config.load_kube_config(config_file="/root/kubeconfig.yaml")

#獲取API的CoreV1Api版本對象
v1 = client.CoreV1Api()

#列出 namespaces
for ns in v1.list_namespace().items:
    print(ns.metadata.name)
    
#列出所有的services
ret = v1.list_service_for_all_namespaces(watch=False)
for i in ret.items:
    print("%s \t%s \t%s \t%s \t%s \n" % (i.kind, i.metadata.namespace, i.metadata.name, i.spec.cluster_ip, i.spec.ports ))
    
#列出所有的pod
ret = v1.list_pod_for_all_namespaces(watch=False)
for i in ret.items:
    print("%s\t%s\t%s" % (i.status.pod_ip, i.metadata.namespace, i.metadata.name))

#列出所有deploy
ret = v1.list_deployments_for_all_namespaces(watch=False)
for i in ret.items:
    print("%s\t%s\t%s" % (i.status.pod_ip, i.metadata.namespace, i.metadata.name))
    
##列出其他資源和以上類似，不懂可以查看(kubectl  api-resources)

2、創建k8s資源對象

github:https://github.com/kubernetes-client/python/tree/master/examples

創建資源（提前寫好yaml資源清單）

#創建deploy
[root@k8s-m ~]# cat create_deploy.py
from os import path
import yaml
from kubernetes import client, config

def main():
    config.load_kube_config()

    with open(path.join(path.dirname(__file__), "/root/deploy.yaml")) as f:
        dep = yaml.safe_load(f)
        k8s_apps_v1 = client.AppsV1Api()
        resp = k8s_apps_v1.create_namespaced_deployment(
            body=dep, namespace="default")
        print("Deployment created. status='%s'" % resp.metadata.name)
main()

[root@k8s-m ~]# kubectl get pod 
NAME                        READY   STATUS    RESTARTS   AGE
mydeploy-6946c867dc-bgcld   1/1     Running   0          40s
mydeploy-6946c867dc-rdnvj   1/1     Running   0          40s
[root@k8s-m ~]# kubectl get deploy
NAME       READY   UP-TO-DATE   AVAILABLE   AGE
mydeploy   2/2     2            2           44s


#創建pod例子（其它資源得自己查源碼自己找對應的API）
[root@k8s-m ~]# cat create_pod.py 
from os import path

import yaml

from kubernetes import client, config


def main():
    config.load_kube_config()

    with open(path.join(path.dirname(__file__), "/root/pod.yaml")) as f:
        dep = yaml.safe_load(f)
        k8s_core_v1 = client.CoreV1Api()
        resp = k8s_core_v1.create_namespaced_pod(
            body=dep, namespace="default")
        print("Pod created. status='%s'" % resp.metadata.name)


if __name__ == '__main__':
    main()

##
[root@k8s-m ~]# python3  create_pod.py 
Pod created. status='nginx-pod'
[root@k8s-m ~]# kubectl get pod  nginx-pod
NAME        READY   STATUS    RESTARTS   AGE
nginx-pod   1/1     Running   0          8s

3、刪除資源（我這里展示pod例子，其它資源刪除差不多）

參考地址:/usr/local/python3/lib/python3.6/site-packages/kubernetes/client/

[root@k8s-m ~]# cat  dp.py
from os import path
import yaml
from kubernetes import client, config

def main():
    config.load_kube_config()
    k8s_core_v1 = client.CoreV1Api()
    resp = k8s_core_v1.delete_namespaced_pod(namespace="default",name='nginx-pod')
    print("delete Pod ")

[root@k8s-m ~]# python3 dp.py
delete Pod　　

4、查看資源（類似kubectl get pod xxx -o json）

#查看(read)

[root@k8s-m ~]# cat  rp.py 
from os import path
import yaml
from kubernetes import client, config

def main():
    config.load_kube_config()
    k8s_core_v1 = client.CoreV1Api()
    resp = k8s_core_v1.read_namespaced_pod(namespace="default",name='nginx-pod')
    print("read Pod ")
    #詳細信息
    print(resp)
    #指定信息
    print(resp.spec.containers[0].image)

if __name__ == '__main__':
    main()

[root@k8s-m ~]# python3   rp.py  |tail
            'host_ip': '172.31.250.229',
            'init_container_statuses': None,
            'message': None,
            'nominated_node_name': None,
            'phase': 'Running',
            'pod_ip': '10.244.167.134',
            'qos_class': 'BestEffort',
            'reason': None,
            'start_time': datetime.datetime(2019, 8, 30, 9, 13, 49, tzinfo=tzutc())}}
nginx　

5、修改

[root@k8s-m ~]# cat  pp.py 
from os import path
import yaml
from kubernetes import client, config

def main():
    config.load_kube_config()
    k8s_core_v1 = client.CoreV1Api()
    old_resp = k8s_core_v1.read_namespaced_pod(namespace="default",name='nginx-pod')
    old_resp.spec.containers[0].image = "nginx:alpine"
    #修改鏡像
    new_resp = k8s_core_v1.patch_namespaced_pod(namespace="default",name='nginx-pod',body=old_resp)
    print(new_resp.spec.containers[0].image)
if __name__ == '__main__':
    main()

[root@k8s-m ~]# python3 pp.py 
nginx:alpine