Pod Rolling update

introduce Pod events channel;
add parsing of the MaintenanceWindows section;
skip deleting Etcd key on cluster delete;
use external etcd host;
watch for tpr/pods in the namespace of the operator pod only;

pkg/controller/pod.go

@@ -0,0 +1,134 @@
+package controller
+
+import (
+	"k8s.io/client-go/pkg/api"
+	"k8s.io/client-go/pkg/api/v1"
+	"k8s.io/client-go/pkg/runtime"
+	"k8s.io/client-go/pkg/watch"
+
+	"github.bus.zalan.do/acid/postgres-operator/pkg/spec"
+	"github.bus.zalan.do/acid/postgres-operator/pkg/util"
+)
+
+func (c *Controller) podListFunc(options api.ListOptions) (runtime.Object, error) {
+	var labelSelector string
+	var fieldSelector string
+
+	if options.LabelSelector != nil {
+		labelSelector = options.LabelSelector.String()
+	}
+
+	if options.FieldSelector != nil {
+		fieldSelector = options.FieldSelector.String()
+	}
+	opts := v1.ListOptions{
+		LabelSelector:   labelSelector,
+		FieldSelector:   fieldSelector,
+		Watch:           options.Watch,
+		ResourceVersion: options.ResourceVersion,
+		TimeoutSeconds:  options.TimeoutSeconds,
+	}
+
+	return c.config.KubeClient.CoreV1().Pods(c.config.PodNamespace).List(opts)
+}
+
+func (c *Controller) podWatchFunc(options api.ListOptions) (watch.Interface, error) {
+	var labelSelector string
+	var fieldSelector string
+
+	if options.LabelSelector != nil {
+		labelSelector = options.LabelSelector.String()
+	}
+
+	if options.FieldSelector != nil {
+		fieldSelector = options.FieldSelector.String()
+	}
+
+	opts := v1.ListOptions{
+		LabelSelector:   labelSelector,
+		FieldSelector:   fieldSelector,
+		Watch:           options.Watch,
+		ResourceVersion: options.ResourceVersion,
+		TimeoutSeconds:  options.TimeoutSeconds,
+	}
+
+	return c.config.KubeClient.CoreV1Client.Pods(c.config.PodNamespace).Watch(opts)
+}
+
+func PodNameFromMeta(meta v1.ObjectMeta) spec.PodName {
+	return spec.PodName{
+		Namespace: meta.Namespace,
+		Name:      meta.Name,
+	}
+}
+
+func (c *Controller) podAdd(obj interface{}) {
+	pod, ok := obj.(*v1.Pod)
+	if !ok {
+		return
+	}
+
+	podEvent := spec.PodEvent{
+		ClusterName: util.PodClusterName(pod),
+		PodName:     PodNameFromMeta(pod.ObjectMeta),
+		CurPod:      pod,
+		EventType:   spec.PodEventAdd,
+	}
+
+	c.podCh <- podEvent
+}
+
+func (c *Controller) podUpdate(prev, cur interface{}) {
+	prevPod, ok := prev.(*v1.Pod)
+	if !ok {
+		return
+	}
+
+	curPod, ok := cur.(*v1.Pod)
+	if !ok {
+		return
+	}
+
+	podEvent := spec.PodEvent{
+		ClusterName: util.PodClusterName(curPod),
+		PodName:     PodNameFromMeta(curPod.ObjectMeta),
+		PrevPod:     prevPod,
+		CurPod:      curPod,
+		EventType:   spec.PodEventUpdate,
+	}
+
+	c.podCh <- podEvent
+}
+
+func (c *Controller) podDelete(obj interface{}) {
+	pod, ok := obj.(*v1.Pod)
+	if !ok {
+		return
+	}
+
+	podEvent := spec.PodEvent{
+		ClusterName: util.PodClusterName(pod),
+		PodName:     PodNameFromMeta(pod.ObjectMeta),
+		CurPod:      pod,
+		EventType:   spec.PodEventDelete,
+	}
+
+	c.podCh <- podEvent
+}
+
+func (c *Controller) podEventsDispatcher(stopCh <-chan struct{}) {
+	c.logger.Infof("Watching all pod events")
+	for {
+		select {
+		case event := <-c.podCh:
+			if subscriber, ok := c.clusters[event.ClusterName]; ok {
+				c.logger.Debugf("Sending %s event of pod '%s' to the '%s' cluster channel", event.EventType, event.PodName, event.ClusterName)
+				go subscriber.ReceivePodEvent(event)
+			} else {
+				c.logger.Debugf("Skipping pods unrelated to clusters: %s", event.PodName)
+			}
+		case <-stopCh:
+			return
+		}
+	}
+}