daemonset-primitive

README

DaemonSet Primitive Example

This example demonstrates the usage of the daemonset primitive within the operator component framework. It shows how to manage a Kubernetes DaemonSet as a component of a larger application, utilizing features like:

• Base Construction: Initializing a DaemonSet with basic metadata and spec.
• Feature Mutations: Applying version-gated or conditional changes (sidecars, env vars, annotations) using the Mutator.
• Suspension: Demonstrating the delete-on-suspend behavior unique to DaemonSets.
• Data Extraction: Harvesting information from the reconciled resource.

Directory Structure

• app/: Defines the mock ExampleApp CRD and the controller that uses the component framework.
• features/: Contains modular feature definitions:
  • mutations.go: sidecar injection, env vars, and version-based image updates.
• resources/: Contains the central NewDaemonSetResource factory that assembles all features using the daemonset.Builder.
• main.go: A standalone entry point that demonstrates a single reconciliation loop using a fake client.

Running the Example

You can run this example directly using go run:

go run examples/daemonset-primitive/main.go

This will:

1. Initialize a fake Kubernetes client.
2. Create an ExampleApp owner object.
3. Reconcile the ExampleApp components through multiple spec changes.
4. Print the resulting status conditions.

Documentation

Overview

Package main is the entry point for the daemonset primitive example.