python (k8s) 1. config

1. remote_cluster.py

# -*- coding: utf8 -*-

"""
和远程 kube 集群通信
认证需要创建 barer token

https://kubernetes.io/docs/tasks/access-application-cluster/access-cluster/
"""

from kubernetes import client, config


def main():
    aToken = "<token>"

    # 创建一个配置对象
    aConfiguration = client.Configuration()

    # 对k8s集群指定一个终端
    aConfiguration.host = "http://xxx.xxx.xxx.xxx:443"

    # 为了简单，本例不使用ssl认证
    aConfiguration.verify_ssl = False

    """
    如果有需要：
    configuration.verify_ssl = True
    configuration.ssl_ca_cert = 'certificate' # 证书路径
    """

    aConfiguration.api_key = {"authorization": "Bearer" + aToken}

    # 使用配置创建 api client
    aApiClient = client.ApiClient(aConfiguration)

    # 调用
    v1 = client.CoreV1Api(aApiClient)
    print("Listing pods with their Ips:")
    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
        ))


if __name__ == '__main__':
    main()

2. cluster_config.py

# -*- coding: utf8 -*-

"""
从集群外部导入k8s的配置
"""

from kubernetes import client, config


def main():
    config.load_kube_config()
    v1 = client.CoreV1Api()
    print("Listing pods with their IPs:")
    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))


if __name__ == '__main__':
    main()

3. pod_config.py

# -*- coding: utf8 -*-

from kubernetes import client, config
from kubernetes.client import configuration
from pick import pick


def main():
    contexts, active_context = config.list_kube_config_contexts()
    if not contexts:
        print("Cannot find any context in kube-config file.")
        return

    contexts = [context['name'] for context in contexts]
    active_index = contexts.index(active_context['name'])

    option, _ = pick(contexts, title='Pick the context to load', default_index=active_index)
    config.load_kube_config(context=option)
    print("Active host is %s" % configuration.Configuration().host)

    v1 = client.CoreV1Api()
    print("Listing pods with their IPs:")
    ret = v1.list_pod_for_all_namespaces(watch=False)
    for item in ret.items:
        print("%s\t%s\t%s" %
              (item.status.pod_ip,
               item.metadata.namespace,
               item.metadata.name))


if __name__ == '__main__':
    main()

4. multiple_cluster.py

# -*- coding: utf8 -*-

from kubernetes import client, config
from kubernetes.client import configuration
from pick import pick


def main():
    contexts, active_context = config.list_kube_config_contexts()
    if not contexts:
        print("Cannot find any context in kube-config file.")
        return

    contexts = [context['name'] for context in contexts]
    active_index = contexts.index(active_context['name'])
    cluster1, first_index = pick(contexts, title='Pick the first context', default_index=active_index)
    cluster2, _ = pick(contexts, title='Pick the second context', default_index=first_index)

    client1 = client.CoreV1Api(
        api_client=config.new_client_from_config(context=cluster1)
    )
    client2 = client.CoreV1Api(
        api_client=config.new_client_from_config(context=cluster2)
    )

    print('\nList of pods on %s:' % cluster1)
    for i in client1.list_pod_for_all_namespaces().items:
        print("%s\t%s\t%s" %
              (i.status.pod_ip, i.metadata.namespace, i.metadata.name))

    print("\n\nList of pods on %s:" % cluster2)
    for i in client2.list_pod_for_all_namespaces().items:
        print("%s\t%s\t%s" %
              (i.status.pod_ip, i.metadata.namespace, i.metadata.name))


if __name__ == '__main__':
    main()

5. api_discovery.py

# -*- coding: utf8 -*-

# kubectl api-versions

from kubernetes import client, config


def main():
    # Configs 可以从配置类中直接设置，如果没有参数提供，将从默认地址加载

    config.load_kube_config()
    print('支持的Apis (*标号的是更好的的版本')
    print('%-40s %s' % ('core', ','.join(client.CoreApi().get_api_versions().versions))) # .versions

    for api in client.ApisApi().get_api_versions().groups:  # groups
        versions = []
        for v in api.versions:  # .versions
            name = ''
            if v.version == api.preferred_version.version and len(api.versons) > 1:  # .preferred_version.version
                name += '*'
            name += v.version

            versions.append(name)

        print('%-40s %s' % (api.name, ','.join(versions)))


if __name__ == '__main__':
    main()