I’ve covered Composite Resources (XRs) and Compositions in previous posts. I’ll provide a brief summary here, but you can review them in more detail if needed.. In the next series of posts, I’ll cover how we use Composition patches to pass values between/to related resources (all patch methods are documented here).
It is important to keep the concepts of Composite Resource and Composition clearly separated in your understanding. A Composite Resource (XR) defines a custom API, exposed via kube-apiserver. It selects a Composition that composes it into a collection of Managed Resources . The Composition is simply a ‘recipe’ to compose the Composite Resource(s). We patch to, from, and within Composite Resources via a Composition. We do not patch Compositions.