scheduler-extender

scheduler-extender

An example project for running a kube-scheduler extender webhook handlers in a kubebuilder webhook server.

Test

tests/e2e/ contains e2e test for the scheduler extender using kuttl. The kuttl test manifests can be used to manually set up an environment with a kube-scheduler configured to use the scheduler extender webhook endpoints.

The test creates a 5 node kind cluster, with the control-plane tained, unschedulable by default. A static pod with scheduler name demo-scheduler is created and checked if it's scheduled on a target node. The scheduler extender is configured by setting target and allowed values in a configmap (game-demo in the test case). allowed is a list of nodes that are filtered by the filter endpoint. target is one target node on which the given pod must be scheduled. While scoring the nodes, the target node is given a score of 10 and all the other nodes are scored 5. The test checks to ensure that the pod is always scheduled on the target node.