198  |  Chapter 23: Operator metadata : name : webapp-config-watcher spec : configMap : webapp-config podSelector : app : webapp Reference to ConfigMap to watch Label selector to determine Pods to restart In this definition, the attribute  configMap  references the name of the  ConfigMap  to watch. The field  podSelector  is a collection of labels and their values, which identify the Pods to restart. We can define the type of this custom resource with a CRD, as shown in Example 23-6. Example 23-6. ConfigWatcher CRD apiVersion : apiextensions.k8s.io/v1beta1 kind : CustomResourceDefinition metadata : name : configwatchers.k8spatterns.io spec : scope : Namespaced group : k8spatterns.io version : v1 names : kind : ConfigWatcher singular : configwatcher plural : configwatchers validation : openAPIV3Schema : properties : spec : properties : configMap : type : string description : "Name of the ConfigMap" podSelector : type : object description : "Label selector for Pods" additionalProperties : type : string Connected to a namespace Dedicated API group