kubernetes-py 1.4.7.23

A python module for Kubernetes.

A python module to use Kubernetes. Currently based on the version 1 of the API.

Currently supported Kubernetes objects:

• ~/.kube/config

• Deployment

• Pod

• ReplicationController

• Secret

• Service

• Volume

Usage

Documentation is currently work in progress. Please find some code snippets to help understand how to use this module.

Configuration

By default, the module attempts to load existing configuration from ~/.kube/config. You are welcome to specify another location from where to load a kubeconfig file.

Otherwise, individual configuration parameters can be overridden piecemeal. In this case you must specify kubeconfig=None when initializing a K8sConfig object, otherwise the ~/kube/.config file takes precedence if it exists.

from kubernetes import K8sConfig

# Defaults found in ~/.kube/config
cfg_default = K8sConfig()

# Defaults found in another kubeconfig file
cfg_other = K8sConfig(kubeconfig='/path/to/kubeconfig')

# Overriding the host, using basic auth
cfg_basic = K8sConfig(
    kubeconfig=None,
    api_host=somehost:8888,
    auth=('basic_user', 'basic_passwd')
)

# Overriding the host, using certificates
cfg_cert = K8sConfig(
    kubeconfig=None,
    api_host=somehost:8888,
    cert=('/path/to/cert.crt', '/path/to/cert.key')
)

# Overriding the host, using a Bearer token
cfg_token = K8sConfig(
    kubeconfig=None,
    api_host=somehost:8888,
    token='50a2fabfdd276f573ff97ace8b11c5f4'
)

Containers

This module uses the default container runtime.

Defining a container:

from kubernetes import K8sContainer

container = K8sContainer(name='redis', image='redis:3.0.7')
container.add_port(
    container_port=6379,
    host_port=6379,
    name='redis'
)

Deployments

Creating a Deployment:

from kubernetes import K8sDeployment

deployment = K8sDeployment(
    config=cfg_cert,
    name='my_deployment',
    replicas=3
)
deployment.add_container(container)
deployment.create()

Fetching a Deployment:

from kubernetes import K8sDeployment

deployment = K8sDeployment(config=cfg_cert, name='my_deployment')
deployment.get()

Fetching all available Deployments:

from kubernetes import K8sDeployment

deployment = K8sDeployment(config=cfg_cert, name='my_deployment')
deployment.list()

Updating a Deployment:

from kubernetes import K8sDeployment, K8sContainer

deployment = K8sDeployment(config=cfg_cert, name='my_deployment')
container = K8sContainer(name='nginx', image='nginx:1.7.9')
deployment.add_container(container)
deployment.create()
deployment.set_container_image(name='nginx', image='nginx:1.9.1')
deployment.update()

Scaling a Deployment:

from kubernetes import K8sDeployment, K8sContainer

deployment = K8sDeployment(config=cfg_cert, name='my_deployment')
container = K8sContainer(name='nginx', image='nginx:1.7.9')
deployment.add_container(container)
deployment.set_replicas(3)
deployment.create()
deployment.scale(10)

Deleting a Deployment:

from kubernetes import K8sDeployment

deployment = K8sDeployment(confif=cfg_cert, name='my_deployment')
deployment.delete()

Pods

Creating a Pod:

from kubernetes import K8sPod

pod = K8sPod(config=cfg_basic, name='redis')
pod.add_container(container)
pod.create()

Fetching a Pod:

from kubernetes import K8sPod

pod = K8sPod(config=cfg_token, name='redis')
pod.get()

Fetching all available Pods:

from kubernetes import K8sPod

pod = K8sPod(config=cfg_token, name='redis')
pod.list()

Deleting a Pod:

from kubernetes import K8sPod

pod = K8sPod(config=cfg_cert, name='redis')
pod.delete()

ReplicationController

Creating a ReplicationController:

from kubernetes import K8sReplicationController

rc = K8sReplicationController(
    config=cfg_cert,
    name='redis',
    image='redis:3.2.3',
    replicas=1
)
rc.create()

Fetching a ReplicationController:

from kubernetes import K8sReplicationController

rc = K8sReplicationController(config=cfg_cert, name='redis')
rc.get()

Fetching all available ReplicationControllers:

from kubernetes import K8sReplicationController

rc = K8sReplicationController(config=cfg_cert, name='redis')
rc.list()

Deleting a ReplicationController:

from kubernetes import K8sReplicationController

rc = K8sReplicationController(config=cfg_cert, name='redis')
rc.delete()

Service

Creating a service:

from kubernetes import K8sService

svc = K8sService(config=cfg_cert, name='redis')
svc.add_port(name='redisport', port=31010, target_port='redisport')
svc.add_selector(selector=dict(name='redis'))
svc.set_cluster_ip('192.168.1.100')
svc.create()

Fetching a service:

from kubernetes import K8sService

svc = K8sService(config=cfg_cert, name='redis')
svc.get()

Deleting a service:

from kubernetes import K8sService

svc = K8sService(config=cfg_cert, name='redis')
svc.delete()

Secret

Creating a secret:

from kubernetes import K8sSecret

data = {
    'somehost': {
        'auth': 'sometoken',
        'email': '[e-mail]'
    }
}

secret = K8sSecret(config=cfg_cert, name='my_registry')
secret.set_dockercfg_secret(data=data)
secret.create()

Fetching a secret:

from kubernetes import K8sSecret

secret = K8sSecret(config=cfg_cert, name='my_registry')
secret.get()

Deleting a secret:

from kubernetes import K8sSecret

secret = K8sSecret(config=cfg_cert, name='my_registry')
secret.delete()

Volume

We currently support:

• emptyDir

• hostPath

• awsElasticBlockStore

• gcePersistentDisk

• nfs

• gitRepo

Mounting an AWS EBS volume inside a Pod:

from kubernetes import K8sVolume

volume = K8sVolume(
    config=cfg_cert,
    name='aws-volume',
    type='awdElasticBlockStore',
    mount_path='/path/inside/container'
)
volume.set_volume_id('vol-123456')  # this volume must already exist
container.add_volume_mount(volume)
pod.add_volume(volume)
pod.add_container(container)
pod.create()

Unit tests

Development of features and unit tests was done against both a full Kubernetes cluster, as well as using the minikube tool. You will find a ./bin/minukube.sh script in the source tree which fetches the application binary.

The unit tests which require making remote API calls check if there is a reachable API server; if no such endpoint is found, the test is skipped. It is recommended to begin testing things out against minikube. However, be aware that minikube does not support the entire feature set of a full Kubernetes install (eg. Deployments).

$ nosetests --with-coverage --cover-package=kubernetes

Please note that when using minikube, the generated ~/.minikube/ca.crt defines the following hosts:

• kubernetes

• kubernetes.default

• kubernetes.default.svc

• kubernetes.default.svc.cluster.local

For certificate validation to succeed, you should edit your ~/.kube/config to address one of the hosts:

- cluster:
    certificate-authority: /Users/kubernetes/.minikube/ca.crt
    server: https://kubernetes:8443

And also add an entry to your /etc/hosts file for the host alias you choose.