pdb-primitive

PodDisruptionBudget Primitive Example

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

• Base Construction: Initializing a PDB with a percentage-based MinAvailable and a label selector.
• Feature Mutations: Switching between MinAvailable and MaxUnavailable based on a feature toggle via EditSpec.
• Metadata Mutations: Setting version labels on the PDB via EditObjectMetadata.
• Data Extraction: Inspecting the reconciled PDB's disruption policy after each sync cycle.

Directory Structure

• app/: Defines the controller that uses the component framework. The ExampleApp CRD is shared from examples/shared/app.
• features/: Contains modular feature definitions:
  • mutations.go: version labelling and feature-gated strict availability.
• resources/: Contains the central NewPDBResource factory that assembles all features using pdb.Builder.
• main.go: A standalone entry point that demonstrates multiple reconciliation cycles with a fake client.

Running the Example

go run examples/pdb-primitive/main.go

This will:

1. Initialize a fake Kubernetes client.
2. Create an ExampleApp owner object.
3. Reconcile through four spec variations, printing the PDB disruption policy after each cycle.
4. Print the resulting status conditions.