python调用kubernetesAPI简单使用

K8s也提供API接口，提供这个接口的是管理节点的apiserver组件，apiserver服务负责提供HTTP API，以便用户、其他组件相互通信。

客户端库： https://kubernetes.io/zh/docs/reference/using-api/client-libraries/

安装

pip install kubernetes -i https://pypi.douban.com/simple

k8s认证方式

• HTTPS 证书认证：基于CA证书签名的数字证书认证
• HTTP Token认证：通过一个Token来识别用户

HTTPS证书认证（kubeconfig）

import os
from kubernetes import client, config
config.load_kube_config(file_path)  # 指定kubeconfig配置文件
apps_api = client.AppsV1Api()  # 资源接口类实例化

for dp in apps_api.list_deployment_for_all_namespaces().items:
    print(dp)

HTTP Token认证（ServiceAccount）

from kubernetes import client, config
configuration = client.Configuration()
configuration.host = "https://192.168.3.201:16443"  # APISERVER地址
configuration.ssl_ca_cert="ca.crt"  # CA证书 /etc/kubernetes/pki/ca.crt
configuration.verify_ssl = True   # 启用证书验证
configuration.api_key = {"authorization": "Bearer " + token}  # 指定Token字符串
client.Configuration.set_default(configuration)
apps_api = client.AppsV1Api() 

这2个认证，2选1

获取Token字符串：创建service account并绑定默认cluster-admin管理员集群角色：

创建用户

$ kubectl create serviceaccount dashboard-admin -n kube-system

用户授权

$ kubectl create clusterrolebinding dashboard-admin --clusterrole=cluster-admin --serviceaccount=kube-system:dashboard-admin

获取用户Token

$ kubectl describe secrets -n kube-system $(kubectl -n kube-system get secret | awk ‘/dashboard-admin/{print $1}’)

其他常用资源接口类实例化：

core_api = client.CoreV1Api()  # namespace,pod,service,pv,pvc
apps_api = client.AppsV1Api()  # deployment
networking_api = client.NetworkingV1beta1Api()  # ingress
storage_api = client.StorageV1Api()  # storage_class

举个例子
Deployment操作：

# 先得有上面的认证，下面的代码才行
# 创建
namespace = "default"
name = "api-test"
replicas = 3
labels = {'nginx':'true'}  # 不区分数据类型，都要加引号
image = "nginx"
body = client.V1Deployment(
            api_version="apps/v1",
            kind="Deployment",
            metadata=client.V1ObjectMeta(name=name),
            spec=client.V1DeploymentSpec(
                replicas=replicas,
                selector={'matchLabels': labels},
                template=client.V1PodTemplateSpec(
                    metadata=client.V1ObjectMeta(labels=labels),
                    spec=client.V1PodSpec(
                        containers=[client.V1Container(
                            name="web",
                            image=image
                        )]
                    )
                ),
            )
        )
try:
    apps_api.create_namespaced_deployment(namespace=namespace, body=body)
except Exception as e:
    status = getattr(e, "status")
    if status == 400:
        print(e)
        print("格式错误")
    elif status == 403:
        print("没权限")
# 删除

name = "api-test"
apps_api.delete_namespaced_deployment(namespace=namespace, name=name)

老实说 这个API挺绕的 ，一个创建deployment的，这里N多的类的对象。
后边我会继续更新这个。