The Kubernetes API and API server

If you’re new to the concept of APIs, you should think of the Kubernetes API as a catalog listing every possible Kubernetes object and their properties. This catalog (API) is accessed via the API server.

For example, Kubernetes defines a lot of objects such as pods, deployments, replicasets, statefulsets, cronjobs, services, ingresses, network policies, and more. All of these are defined in the API, along with all of their properties that can be used to configure them. When you deploy an object, such as a deployment, you define it in a declarative manifest that you send to the API server where it’s authenticated, authorised, and scheduled to the cluster.

If you try to deploy an object that isn’t defined in the API, the operation will fail. Also, if you try and configure a property of an object that no longer exists, it will fail.

The Kubernetes API is divided into named groups to make it easier to understand, navigate, and expand...