Merge pull request kubernetes#19203 from wojtek-t/logging_for18928

Extend logging for debugging kubernetes#18794 purposes

Author: wojtek-t

pkg/storage/cacher.go

@@ -414,6 +414,11 @@ func (c *Cacher) LastSyncResourceVersion() (uint64, error) {
 	return strconv.ParseUint(resourceVersion, 10, 64)
 }
 
+// For debugging #18794 only.
+func (c *Cacher) GetAllCachedEvents() ([]watchCacheEvent, error) {
+	return c.watchCache.getAllCachedEvents()
+}
+
 // cacherListerWatcher opaques storage.Interface to expose cache.ListerWatcher.
 type cacherListerWatcher struct {
 	storage        Interface

pkg/storage/cacher_test.go

@@ -37,6 +37,7 @@ import (
 	"k8s.io/kubernetes/pkg/util/sets"
 	"k8s.io/kubernetes/pkg/watch"
 
+	"github.com/golang/glog"
 	"golang.org/x/net/context"
 )
 
@@ -299,6 +300,15 @@ func TestFiltering(t *testing.T) {
 	}
 	watcher, err := cacher.Watch(context.TODO(), "pods/ns/foo", fooCreated.ResourceVersion, filter)
 	if err != nil {
+		// For debugging #18794 only.
+		events, err := cacher.GetAllCachedEvents()
+		if err != nil {
+			glog.Error("Unexpected error: %v", err)
+		} else {
+			for _, event := range events {
+				glog.Errorf("cached event: %s %#v", event.Type, event.Object)
+			}
+		}
 		t.Fatalf("Unexpected error: %v", err)
 	}
 	defer watcher.Stop()

pkg/storage/watch_cache.go

@@ -298,3 +298,13 @@ func (w *watchCache) GetAllEventsSince(resourceVersion uint64) ([]watchCacheEven
 	defer w.RUnlock()
 	return w.GetAllEventsSinceThreadUnsafe(resourceVersion)
 }
+
+// For debugging #18794 only.
+func (w *watchCache) getAllCachedEvents() ([]watchCacheEvent, error) {
+	w.RLock()
+	defer w.RUnlock()
+	if w.startIndex == w.endIndex {
+		return make([]watchCacheEvent, 0), nil
+	}
+	return w.GetAllEventsSinceThreadUnsafe(w.cache[w.startIndex%w.capacity].resourceVersion)
+}