kubecrd 0.1.0

Create Kubernetes CRD using Python dataclasses

The primary purpose of this project is to simplify working with Kubernetes Custom Resources. To achieve that it provides a base class, kubecrd.OpenAPISchemaBase that can convert regular Python dataclassses into Kubernetes Custom Resource Definitions.

>>> from dataclasses import dataclass, field
>>> from uuid import UUID
>>> from kubecrd import OpenAPISchemaBase
>>> from apischema import schema

>>> @dataclass
... class Resource(OpenAPISchemaBase):
...     __group__ = 'example.com'
...     __version__ = 'v1alpha1'
...
...     name: str
...     tags: list[str] = field(
...         default_factory=list,
...         metadata=schema(
...            description='regroup multiple resources',
...            unique=False,
...         ),
...     )

>>> print(Resource.crd_schema())
apiVersion: apiextensions.k8s.io/v1
kind: CustomResourceDefinition
metadata:
  name: resources.example.com
spec:
  group: example.com
  names:
    kind: Resource
    plural: resources
    singular: resource
  scope: Namespaced
  versions:
  - name: v1alpha1
    schema:
      openAPIV3Schema:
        properties:
          spec:
            properties:
              name:
                type: string
              tags:
                default: []
                description: regroup multiple resources
                items:
                  type: string
                type: array
                uniqueItems: false
            required:
            - name
            type: object
        type: object
    served: true
    storage: true
<BLANKLINE>

It is also possible to install the CRD in a cluster using a Kubernetes Client object:

from from kubernetes import client, config
config.load_kube_config()
k8s_client = client.ApiClient()
Resource.install(k8s_client)

You can then find the resource in the cluster:

» kubectl get crds/resources.example.com
NAME                    CREATED AT
resources.example.com   2022-03-20T03:58:25Z

$ kubectl api-resources | grep example.com
resources     example.com/v1alpha1                  true         Resource

Installation of resource is idempotent, so re-installing an already installed resource doesn’t raise any exceptions if exist_ok=True is passed in:

Resource.install(k8s_client, exist_ok=True)