sablier/pkg/provider/kubernetes/deployment_events.go

package kubernetes

import (
	appsv1 "k8s.io/api/apps/v1"
	core_v1 "k8s.io/api/core/v1"
	"k8s.io/client-go/informers"
	"k8s.io/client-go/tools/cache"
	"time"
)

func (p *Provider) watchDeployents(instance chan<- string) cache.SharedIndexInformer {
	handler := cache.ResourceEventHandlerFuncs{
		UpdateFunc: func(old, new interface{}) {
			newDeployment := new.(*appsv1.Deployment)
			oldDeployment := old.(*appsv1.Deployment)

			if newDeployment.ObjectMeta.ResourceVersion == oldDeployment.ObjectMeta.ResourceVersion {
				return
			}

			if *oldDeployment.Spec.Replicas == 0 {
				return
			}

			if *newDeployment.Spec.Replicas == 0 {
				parsed := DeploymentName(newDeployment, ParseOptions{Delimiter: p.delimiter})
				instance <- parsed.Original
			}
		},
		DeleteFunc: func(obj interface{}) {
			deletedDeployment := obj.(*appsv1.Deployment)
			parsed := DeploymentName(deletedDeployment, ParseOptions{Delimiter: p.delimiter})
			instance <- parsed.Original
		},
	}
	factory := informers.NewSharedInformerFactoryWithOptions(p.Client, 2*time.Second, informers.WithNamespace(core_v1.NamespaceAll))
	informer := factory.Apps().V1().Deployments().Informer()

	informer.AddEventHandler(handler)
	return informer
}