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 and Description
Result	reconcile(Request request) Reconcile result.

Method Detail

reconcile

Result reconcile(Request request)

Reconcile result.

Parameters:

request - the reconcile request, triggered by watch events

Returns:

the result