Feature: Support for Flux OCI features

[kingdonb]

Flux has support for HelmRepository objects with type: oci since 0.31.0, released in June.

Flux also has a POC for the Kustomize controller supporting OCI, with a new OCIRepository kind that has only been published in pre-release. It is blocking on the reviews of fluxcd/flux2#2601. We need user and maintainer reviews of this feature to ensure that it is correct before the work on the final implementation can begin.

But for now, we have an implementation of this RFC:

• [RFC-0003] Flux OCI support for Kubernetes manifests fluxcd/flux2#2601

implemented as Proof of Concept in:

• [RFC-0003] Add support for OCIRepository sources fluxcd/kustomize-controller#684
• [RFC-0003] Implement OCIRepository reconciliation fluxcd/source-controller#788
• [RFC-0003] Add commands for managing OCI artifacts fluxcd/flux2#2856

We should support the Helm OCI work that has already been released through the stable channel, and the OCIRepository work that is proposed through the prerelease channel of the VSCode extension. 👍 This feature is currently planned for target to release in 0.21.

[kingdonb]

Here is the current state (I have an OCIRepository which is not listed in Sources, and a Flux Kustomization which applies from it)

The flux tree ks river-data-oci looks like:

$ flux tree ks river-data-oci
Kustomization/flux-system/river-data-oci
├── Namespace/default
├── Service/default/river-data
├── Deployment/default/river-data
└── Ingress/default/river-data

It is probably one of these options, as all of the non-OCI things show fine what resources their tree has under them:

sourceRef:
  kind: OCIRepository
  name: river-data-oci
targetNamespace: default

It still reads the specs OK ☝️

I have not tested against Helm Controller's OCI-based repository source at all (that's next)

The experiment is being run out of here and here:

• OCI release experiment juozasg/river-data-explorer#2
• https://github.com/kingdonb/tailscale-k8s/tree/main/apps/worker/river-data-explorer

[kingdonb]

This has landed and is in 0.21.0 🎉