configmap-primitive

ConfigMap Primitive Example

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

• Base Construction: Initializing a ConfigMap with basic metadata.
• Feature Mutations: Composing YAML configuration from independent, feature-gated mutations using MergeYAML.
• Metadata Mutations: Setting version labels on the ConfigMap via EditObjectMetadata.
• Data Extraction: Harvesting ConfigMap entries after each reconcile 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: base config, version labelling, and feature-gated tracing and metrics sections.
• resources/: Contains the central NewConfigMapResource factory that assembles all features using configmap.Builder.
• main.go: A standalone entry point that demonstrates multiple reconciliation cycles with a fake client.

Running the Example

go run examples/configmap-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 composed app.yaml after each cycle.
4. Print the resulting status conditions.