Package io.kubernetes.client.extended.controller.reconciler

Interface Reconciler

public interface Reconciler
Reconciler defines interface for reconciling resource. Users are expected to implement this interface to develop their own controllers watching events on resources. A reconciler works by comparing the state specified in an object by a user against the actual cluster state, and then perform operations to make the actual cluster state reflect the state specified by the user. Typically, reconcile is triggered by a Controller in response to cluster Events (e.g. Creating, Updating, Deleting Kubernetes objects) or external Events (GitHub Webhooks, polling external sources, etc).

Example reconcile Logic:

1. Read an object and all the Pods it owns. 2. Observe that the object spec specifies 5 replicas but actual cluster contains only 1 Pod replica. 3. Create 4 Pods and set their OwnerReferences to the object.

Reconciliation is level-based, meaning action isn't driven off changes in individual Events, but instead is driven by actual cluster state read from the apiserver or a local cache. For example if responding to a Pod Delete Event, the Request won't contain that a Pod was deleted, instead the reconcile function observes this when reading the cluster state and seeing the Pod as missing.

  • Method Summary

    Modifier and Type
    Method
    Description
    Result
    reconcile(Request request)
    Reconcile result.

  • Method Details

    • reconcile

      Result reconcile(Request request)
      Reconcile result.
      Parameters:
      request - the reconcile request, triggered by watch events
      Returns:
      the result