kr8s: A Python repository from thomasjpfan

A simple, extensible Python client library for Kubernetes that feels familiar for folks who already know how to use kubectl.

Highlights

API inspired by kubectl for a shallow learning curve.
Sensible defaults to reduce boiler plate.
No swagger generated code, human readable code only.
Has both a standard and an async API that can be used with asyncio and trio.
Client caching to reduce passing API objects around.
Batteries included by providing useful utilities and methods inspired by kubectl.

Quickstart

Installation

$ pip install kr8s

Examples

Tip

See the Examples Documentation for a full set of examples including asyncio examples.

List Nodes

Print out all of the node names in the cluster.

import kr8s

for node in kr8s.get("nodes"):
    print(node.name)

Create a Pod

Create a new Pod.

from kr8s.objects import Pod

pod = Pod({
        "apiVersion": "v1",
        "kind": "Pod",
        "metadata": {
            "name": "my-pod",
        },
        "spec": {
            "containers": [{"name": "pause", "image": "gcr.io/google_containers/pause",}]
        },
    })

pod.create()

Scale a Deployment

Scale the Deployment metrics-server in the Namespace kube-system to 1 replica.

from kr8s.objects import Deployment

deploy = Deployment.get("metrics-server", namespace="kube-system")
deploy.scale(1)

List Pods by label selector

Get all Pods from all Namespaces matching a label selector.

import kr8s

selector = {'component': 'kube-scheduler'}

for pod in kr8s.get("pods", namespace=kr8s.ALL, label_selector=selector):
    print(pod.namespace, pod.name)

Add a label to a Pod

Add the label foo with the value bar to an existing Pod.

from kr8s.objects import Pod

pod = Pod("kube-apiserver", namespace="kube-system")
pod.label({"foo": "bar"})

Generate a Pod

Generate a simple Pod with a couple of keyword arguments.

from kr8s.objects import Pod

pod = Pod.gen(name="example-1", image="nginx:latest")
pod.create()

Cordon a Node

Cordon a Node to mark it as unschedulable.

from kr8s.objects import Node

node = Node("k8s-node-1")

node.cordon()

Pod Exec

Exec a command in a Pod.

from kr8s.objects import Pod

pod = Pod.get("my-pod")

command = pod.exec(["uptime"])
print(command.stdout.decode())
# 13:49:05 up 23:03,  0 users,  load average: 0.66, 0.87, 0.85

Port forward a Pod

Open a port forward to a Pod as a background task/thread.

from kr8s.objects import Pod

pod = Pod.get("my-pod")
pf = pod.portforward(remote_port=1234, local_port=5678)

# Starts the port forward in a background thread
pf.start()

# Your other code goes here

# Optionally stop the port forward thread (it will exit with Python anyway)
pf.stop()

Tip