website/content/en/docs/concepts/extend-kubernetes/api-extension
deepsan 84c2324c2b Fix service-catalog usage of apiserver aggregation
The Service Catalog architecture changed from using api aggregation to CRDs, but the docs still refer to the older architecture using api aggregation.

Couple of changes here:
1. Change the sentence on how Service Catalog is implemented
2. Replace the example for usage of api aggregation from service-catalog to metrics-server. There are multiple implementations that can be linked to(keda, prometheus, datadog,...), but keeping the documentation neutral by pointing to kubernetes-sigs/metrics-server

References:
- Service Catalog [v0.3.0 release notes](https://github.com/kubernetes-sigs/service-catalog/releases/tag/v0.3.0):

> In release 0.3.0, we've focused on replacing the Aggregated API Server with the CustomResourceDefinitions (CRDs) and the Admission Webhook solution.

- Project [README](https://github.com/kubernetes-sigs/service-catalog/pull/2691/files)
> Service Catalog recently switched to a new CRDs-based architecture. The old API Server-based implementation is available on the v0.2 branch. We support this implementation by providing bug fixes until July 2020.
2021-09-09 17:58:56 -07:00
..
_index.md Arrange the Extending Kubernetes section in the Concepts TOC (#8569) 2018-05-16 12:26:52 -07:00
apiserver-aggregation.md Fix service-catalog usage of apiserver aggregation 2021-09-09 17:58:56 -07:00
custom-resources.md Reword Go requirement for Aggregated API 2021-08-05 15:07:43 -07:00