Fix graceful shutdown

graceful shutdown of goroutines on operator exit

pkg/controller/controller.go

@@ -169,25 +169,30 @@ func (c *Controller) initController() {
 }
 
 func (c *Controller) Run(stopCh <-chan struct{}, wg *sync.WaitGroup) {
-	defer wg.Done()
-	wg.Add(1)
-
 	c.initController()
 
-	go c.runInformers(stopCh)
+	wg.Add(4)
+	go c.runPodInformer(stopCh, wg)
+	go c.runPostgresqlInformer(stopCh, wg)
+	go c.podEventsDispatcher(stopCh, wg)
+	go c.clusterResync(stopCh, wg)
 
 	for i := range c.clusterEventQueues {
-		go c.processClusterEventsQueue(i)
+		wg.Add(1)
+		go c.processClusterEventsQueue(i, stopCh, wg)
 	}
 
 	c.logger.Info("Started working in background")
 }
 
-func (c *Controller) runInformers(stopCh <-chan struct{}) {
+func (c *Controller) runPodInformer(stopCh <-chan struct{}, wg *sync.WaitGroup) {
-	go c.postgresqlInformer.Run(stopCh)
+	defer wg.Done()
-	go c.podInformer.Run(stopCh)
-	go c.podEventsDispatcher(stopCh)
-	go c.clusterResync(stopCh)
 
-	<-stopCh
+	c.podInformer.Run(stopCh)
+}
+
+func (c *Controller) runPostgresqlInformer(stopCh <-chan struct{}, wg *sync.WaitGroup) {
+	defer wg.Done()
+
+	c.postgresqlInformer.Run(stopCh)
 }

pkg/controller/pod.go

@@ -1,6 +1,8 @@
 package controller
 
 import (
+	"sync"
+
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/apimachinery/pkg/watch"
@@ -97,7 +99,9 @@ func (c *Controller) podDelete(obj interface{}) {
 	c.podCh <- podEvent
 }
 
-func (c *Controller) podEventsDispatcher(stopCh <-chan struct{}) {
+func (c *Controller) podEventsDispatcher(stopCh <-chan struct{}, wg *sync.WaitGroup) {
+	defer wg.Done()
+
 	c.logger.Debugln("Watching all pod events")
 	for {
 		select {

pkg/controller/postgresql.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"reflect"
+	"sync"
 	"sync/atomic"
 	"time"
 
@@ -19,7 +20,8 @@ import (
 	"github.com/zalando-incubator/postgres-operator/pkg/util/constants"
 )
 
-func (c *Controller) clusterResync(stopCh <-chan struct{}) {
+func (c *Controller) clusterResync(stopCh <-chan struct{}, wg *sync.WaitGroup) {
+	defer wg.Done()
 	ticker := time.NewTicker(c.opConfig.ResyncPeriod)
 
 	for {
@@ -226,12 +228,17 @@ func (c *Controller) processEvent(obj interface{}) error {
 	return nil
 }
 
-func (c *Controller) processClusterEventsQueue(idx int) {
+func (c *Controller) processClusterEventsQueue(idx int, stopCh <-chan struct{}, wg *sync.WaitGroup) {
-	for {
+	defer wg.Done()
+
+	go func() {
 		if _, err := c.clusterEventQueues[idx].Pop(cache.PopProcessFunc(c.processEvent)); err != nil {
 			c.logger.Errorf("error when processing cluster events queue: %v", err)
 		}
-	}
+	}()
+
+	<-stopCh
+	c.clusterEventQueues[idx].Close()
 }
 
 func (c *Controller) queueClusterEvent(old, new *spec.Postgresql, eventType spec.EventType) {