pytest-kind 22.11.1

Description:

pytestkind 22.11.1

pytest-kind





Test your Python Kubernetes app/operator end-to-end with kind and pytest.
pytest-kind is a plugin for pytest which provides the kind_cluster fixture.
The fixture will install kind 0.17.0, create a Kubernetes 1.25 cluster, and provide convenience functionality such as port forwarding.
Usage
Install pytest-kind via pip or via poetry, e.g.:
poetry add --dev pytest-kind

Write your pytest functions and use the provided kind_cluster fixture, e.g.:
def test_kubernetes_version(kind_cluster):
assert kind_cluster.api.version == ('1', '25')

To load your custom Docker image and apply deployment manifests:
import requests
from pykube import Pod

def test_myapp(kind_cluster):
kind_cluster.load_docker_image("myapp")
kind_cluster.kubectl("apply", "-f", "deployment.yaml")
kind_cluster.kubectl("rollout", "status", "deployment/myapp")

# using Pykube to query pods
for pod in Pod.objects(kind_cluster.api).filter(selector="app=myapp"):
assert "Sucessfully started" in pod.logs()

with kind_cluster.port_forward("service/myapp", 80) as port:
r = requests.get(f"http://localhost:{port}/hello/world")
r.raise_for_status()
assert r.text == "Hello world!"

See the examples directory for sample projects and also check out kube-web-view which uses pytest-kind for its e2e tests.
KindCluster object
The kind_cluster fixture is an instance of the KindCluster class with the following methods:

load_docker_image(docker_image): load the specified Docker image into the kind cluster
kubectl(*args): run the kubectl binary against the cluster with the specified arguments. Returns the process output as string.
port_forward(service_or_pod_name, remote_port, *args): run "kubectl port-forward" for the given service/pod and return the (random) local port. To be used as context manager ("with" statement). Pass the namespace as additional args to kubectl via "-n", "mynamespace".

KindCluster has the following attributes:

name: the kind cluster name
kubeconfig_path: the path to the Kubeconfig file to access the cluster
kind_path: path to the kind binary
kubectl_path: path to the kubectl binary
api: pykube HTTPClient instance to access the cluster from Python

You can also use KindCluster directly without pytest:
from pytest_kind import KindCluster

cluster = KindCluster("myclustername")
cluster.create()
cluster.kubectl("apply", "-f", "..")
# ...
cluster.delete()

Pytest Options
The kind cluster name can be set via the --cluster-name CLI option.
The kind cluster is deleted after each pytest session, you can keep the cluster by passing --keep-cluster to pytest.
Note that you can use the PYTEST_ADDOPTS environment variable to pass these options to pytest. This also works if you call pytest from a Makefile:
# for test debugging: don't delete the kind cluster
PYTEST_ADDOPTS=--keep-cluster make test

Notes

The kind_cluster fixture is session-scoped, i.e. the same cluster will be used across all test modules/functions.
The kind and kubectl binaries will be downloaded once to the local directory ./.pytest-kind/{cluster-name}/. You can use them to interact with the cluster (e.g. when --keep-cluster is used).
Some cluster pods might not be ready immediately (e.g. kind's CoreDNS take a moment), add wait/poll functionality as required to make your tests predictable.