Summary
In this chapter, we covered three major topics: working with the Kubernetes API, extending the Kubernetes API, and writing Kubernetes plugins. The Kubernetes API supports the OpenAPI spec and is a great example of REST API design that follows all current best practices. It is very consistent, well organized, and well documented. Yet it is a big API and not easy to understand. You can access the API directly via REST over HTTP, using client libraries including the official Python client, and even by invoking kubectl programmatically.
Extending the Kubernetes API may involve defining your own custom resources, writing controllers/operators, and optionally extending the API server itself via API aggregation.
Plugins and webhooks are a foundation of Kubernetes design. Kubernetes was always meant to be extended by users to accommodate any needs. We looked at various plugins, such as custom schedulers, kubectl plugins, and access control webhooks. It is very cool that Kubernetes...