Project Gardener implements the automated management and operation of Kubernetes clusters as a service. Its main principle is to leverage Kubernetes concepts for all of its tasks.
Recently, most of the vendor specific logic has been developed in-tree. However, the project has grown to a size where it is very hard to extend, maintain, and test. With GEP-1 we have proposed how the architecture can be changed in a way to support external controllers that contain their very own vendor specifics. This way, we can keep Gardener core clean and independent.
This controller implements Gardener's extension contract for the shoot-lakom-service extension.
An example for a ControllerRegistration resource that can be used to register this controller to Gardener can be found here.
Please find more information regarding the extensibility concepts and a detailed proposal here.
Lakom is kubernetes admission controller which purpose is to implement cosign image signature verification against public cosign key. It also takes care to resolve image tags to sha256 digests. It also caches all OCI artifacts to reduce the load toward the OCI registry.
Example extension resource:
apiVersion: extensions.gardener.cloud/v1alpha1
kind: Extension
metadata:
name: extension-shoot-lakom-service
namespace: shoot--project--abc
spec:
type: shoot-lakom-serviceWhen an extension resource is reconciled, the extension controller will create an instance of lakom admission controller. These resources are placed inside the shoot namespace on the seed. Also, the controller takes care about generating necessary RBAC resources for the seed as well as for the shoot.
Please note, this extension controller relies on the Gardener-Resource-Manager to deploy k8s resources to seed and shoot clusters.
The Lakom admission controller can be configured with make dev-setup and started with make start-lakom.
You can run the lakom extension controller locally on your machine by executing make start.
If you'd like to develop Lakom using a local cluster such as KinD, make sure your KUBECONFIG environment variable is targeting the local Garden cluster.
Add 127.0.0.1 garden.local.gardener.cloud to your /etc/hosts. You can then run:
make extension-upThis will trigger a skaffold deployment that builds the images, pushes them to the registry and installs the helm charts from /charts.
We are using Go modules for Golang package dependency management and Ginkgo/Gomega for testing.
Feedback and contributions are always welcome. Please report bugs or suggestions as GitHub issues or join our Slack channel #gardener (please invite yourself to the Kubernetes workspace here).
Please find further resources about out project here: