Avoid passing the role into the recreatePod.

Conceptually, the operator's task is just to change the pod. As it
has no influence over the role the pod will take (either the master
or a replica), it shouldn't wait for the specific role.

This fixes at least one issue, where the pod running in a single-pod
cluster has been waited for forever by the operator expecting it to
have a wrong role (since Patroni callback assiging it the original
replica role has been killed after a quick promote by the next
callback.)

pkg/cluster/pod.go

@@ -112,7 +112,7 @@ func (c *Cluster) registerPodSubscriber(podName spec.PodName) chan spec.PodEvent
 	return ch
 }
 
-func (c *Cluster) recreatePod(pod v1.Pod, spiloRole string) error {
+func (c *Cluster) recreatePod(pod v1.Pod) error {
 	podName := spec.PodName{
 		Namespace: pod.Namespace,
 		Name:      pod.Name,
@@ -133,7 +133,7 @@ func (c *Cluster) recreatePod(pod v1.Pod, spiloRole string) error {
 	if err := c.waitForPodDeletion(ch); err != nil {
 		return err
 	}
-	if err := c.waitForPodLabel(ch, spiloRole); err != nil {
+	if err := c.waitForPodLabel(ch); err != nil {
 		return err
 	}
 	c.logger.Infof("Pod '%s' is ready", podName)
@@ -184,7 +184,7 @@ func (c *Cluster) recreatePods() error {
 			continue
 		}
 
-		err = c.recreatePod(pod, "replica")
+		err = c.recreatePod(pod)
 		if err != nil {
 			return fmt.Errorf("Can't recreate replica Pod '%s': %s", util.NameFromMeta(pod.ObjectMeta), err)
 		}
@@ -197,7 +197,7 @@ func (c *Cluster) recreatePods() error {
 	//TODO: specify master, leave new master empty
 	c.logger.Infof("Recreating master Pod '%s'", util.NameFromMeta(masterPod.ObjectMeta))
 
-	if err := c.recreatePod(masterPod, "replica"); err != nil {
+	if err := c.recreatePod(masterPod); err != nil {
 		return fmt.Errorf("Can't recreate master Pod '%s': %s", util.NameFromMeta(masterPod.ObjectMeta), err)
 	}
 

pkg/cluster/sync.go

@@ -152,7 +152,6 @@ func (c *Cluster) syncPods() error {
 
 	//First check if we have left overs from the previous rolling update
 	for _, pod := range pods.Items {
-		podRole := util.PodSpiloRole(&pod)
 		podName := spec.PodName{
 			Namespace: pod.Namespace,
 			Name:      pod.Name,
@@ -161,7 +160,7 @@ func (c *Cluster) syncPods() error {
 		if match && pod.Status.Phase == v1.PodPending {
 			c.logger.Infof("Waiting for left over Pod '%s'", podName)
 			ch := c.registerPodSubscriber(podName)
-			c.waitForPodLabel(ch, podRole)
+			c.waitForPodLabel(ch)
 			c.unregisterPodSubscriber(podName)
 		}
 	}
@@ -177,7 +176,7 @@ func (c *Cluster) syncPods() error {
 		if util.PodSpiloRole(&pod) == "master" {
 			//TODO: do manual failover first
 		}
-		err = c.recreatePod(pod, "replica") // newly created pods are always "replica"s
+		err = c.recreatePod(pod)
 
 		c.logger.Infof("Pod '%s' has been successfully recreated", util.NameFromMeta(pod.ObjectMeta))
 	}

pkg/cluster/util.go

@@ -146,12 +146,15 @@ func (c *Cluster) getTeamMembers() ([]string, error) {
 	return teamInfo.Members, nil
 }
 
-func (c *Cluster) waitForPodLabel(podEvents chan spec.PodEvent, spiloRole string) error {
+func (c *Cluster) waitForPodLabel(podEvents chan spec.PodEvent) error {
 	for {
 		select {
 		case podEvent := <-podEvents:
 			role := util.PodSpiloRole(podEvent.CurPod)
-			if role == spiloRole { // TODO: newly-created Pods are always replicas => check against empty string only
+			// We cannot assume any role of the newly created pod. Normally, for a multi-pod cluster
+			// we should observe the 'replica' value, but it could be that some pods are not allowed
+			// to promote, therefore, the new pod could be a master as well.
+			if role == "master" || role == "replica" {
 				return nil
 			}
 		case <-time.After(c.OpConfig.PodLabelWaitTimeout):