Feed-ingress does not work on Kubernetes 1.22+

[howardburgess]

Attempting to run feed-ingress on a Kubernetes 1.22 cluster, we noticed that feed does not support the networking.k8s.io/v1 Ingress API. It only watches for extensions/v1beta1.

• Ingress in extensions/v1beta1 was deprecated in v1.14 (replacement networking.k8s.io/v1beta1)
• Ingress in networking.k8s.io/v1beta1 was deprecated in v1.19 (replacement networking.k8s.io/v1)
• extensions/v1beta1 and networking.k8s.io/v1beta1 were removed in v1.22.

❯ kubectl version --short
Client Version: v1.22.3
Server Version: v1.22.6-gke.300

❯ kubectl -n feed logs feed-b7rkz8s2-6bcb84bbb5-42blg --tail=5
E0407 08:29:04.335054       1 reflector.go:125] pkg/mod/k8s.io/[email protected]/tools/cache/reflector.go:98: Failed to list *v1beta1.Ingress: the server could not find the requested resource (get ingresses.extensions)
E0407 08:29:05.338233       1 reflector.go:125] pkg/mod/k8s.io/[email protected]/tools/cache/reflector.go:98: Failed to list *v1beta1.Ingress: the server could not find the requested resource (get ingresses.extensions)
time="2022-04-07T08:29:06Z" level=info msg="Signalled terminated, shutting down gracefully" source="cmd/cmd.go:92"
time="2022-04-07T08:29:06Z" level=info msg="Stopping controller" source="controller/controller.go:419"
time="2022-04-07T08:29:06Z" level=info msg="Controller has stopped" source="controller/controller.go:430"

❯ kubectl api-resources | grep ingresses
ingresses                         ing            networking.k8s.io/v1                   true         Ingress

Compare with a Kubernetes 1.21 cluster:

❯ kubectl --context dev.ce.europe-west1-gcp.npottdc.sky api-resources | grep ingresses
ingresses                          ing            extensions/v1beta1                     true         Ingress
ingresses                          ing            networking.k8s.io/v1                   true         Ingress

Kubernetes 1.22 also introduced the IngressClass resource which will replace the kubernetes.io/ingress.class annotation on Ingresses. The annotation is deprecated but still supported.

[howardburgess]

We could:

• Add a flag to make it support Ingress in the new API group. There are lots of references to extensions/v1beta1 in the code.
• Make it only watch for the new group, hence a breaking change since it would only work with Kubernetes 1.19+ (which reached end of life on 28 October 2021)

[howardburgess]

Since #248 and #249, Feed now supports Kubernetes 1.19+. Released in v6.0.0