Pass last resource version to restart watch

kubewatcher/kubewatcher.go

@@ -25,6 +25,7 @@ import (
 	"log"
 	"strings"
 	"sync/atomic"
+	"time"
 
 	"k8s.io/client-go/1.5/kubernetes"
 	"k8s.io/client-go/1.5/pkg/api"
@@ -51,6 +52,7 @@ type (
 	watchSubscription struct {
 		fission.Watch
 		kubeWatch           watch.Interface
+		lastResourceVersion string
 		stopped             *int32
 		kubernetesClient    *kubernetes.Clientset
 		publisher           Publisher
@@ -137,11 +139,16 @@ func printKubernetesObject(obj runtime.Object, w io.Writer) error {
 	return err
 }
 
-func createKubernetesWatch(kubeClient *kubernetes.Clientset, w *fission.Watch) (watch.Interface, error) {
+func createKubernetesWatch(kubeClient *kubernetes.Clientset, w *fission.Watch, resourceVersion string) (watch.Interface, error) {
 	var wi watch.Interface
 	var err error
+	var watchTimeoutSec int64 = 300
 
-	listOptions := api.ListOptions{} // TODO populate labelselector and fieldselector
+	// TODO populate labelselector and fieldselector
+	listOptions := api.ListOptions{
+		ResourceVersion: resourceVersion,
+		TimeoutSeconds:  &watchTimeoutSec,
+	}
 
 	// TODO handle the full list of types
 	switch strings.ToUpper(w.ObjType) {
@@ -203,20 +210,22 @@ func MakeWatchSubscription(w *fission.Watch, kubeClient *kubernetes.Clientset, p
 		stopped:             &stopped,
 		kubernetesClient:    kubeClient,
 		publisher:           publisher,
+		lastResourceVersion: "",
 	}
 
 	err := ws.restartWatch()
 	if err != nil {
-		return err
+		return nil, err
 	}
 
 	go ws.eventDispatchLoop()
+	return ws, nil
 }
 
 func (ws *watchSubscription) restartWatch() error {
 	retries := 60
 	for {
-		wi, err := createKubernetesWatch(kubeClient, w)
+		wi, err := createKubernetesWatch(ws.kubernetesClient, &ws.Watch, ws.lastResourceVersion)
 		if err != nil {
 			retries--
 			if retries > 0 {
@@ -227,7 +236,7 @@ func (ws *watchSubscription) restartWatch() error {
 			}
 		}
 		ws.kubeWatch = wi
-		return
+		return nil
 	}
 }
 
@@ -240,6 +249,8 @@ func (ws *watchSubscription) eventDispatchLoop() {
 				log.Println("Watch stopped", ws.Watch.Metadata.Name)
 				break
 			}
+			// TODO: update ws.lastResourceVersion
+
 			ws.publisher.Publish(ev, ws.Watch.Target)
 		}
 		if atomic.LoadInt32(ws.stopped) == 0 {