plugin/kubernetes: Fix dns programming duration metric (#4255)

* get data reqd to record latency before calling toFuncs
* refactor out unnecessary toFunc wrappers
* remove latency metric unit tests per PR feedback

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

1 files changed, 16 insertions, 5 deletions

diff --git a/plugin/kubernetes/object/informer.go b/plugin/kubernetes/object/informer.go
index afd134e56..e44cd218a 100644
--- a/plugin/kubernetes/object/informer.go
+++ b/plugin/kubernetes/object/informer.go
@@ -1,6 +1,8 @@
 package object
 
 import (
+	"fmt"
+
 	meta "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
 	"k8s.io/client-go/tools/cache"
@@ -25,13 +27,18 @@ func NewIndexerInformer(lw cache.ListerWatcher, objType runtime.Object, h cache.
 type RecordLatencyFunc func(meta.Object)
 
 // DefaultProcessor is based on the Process function from cache.NewIndexerInformer except it does a conversion.
-func DefaultProcessor(convert ToFunc, recordLatency RecordLatencyFunc) ProcessorBuilder {
+func DefaultProcessor(convert ToFunc, recordLatency *EndpointLatencyRecorder) ProcessorBuilder {
 	return func(clientState cache.Indexer, h cache.ResourceEventHandler) cache.ProcessFunc {
 		return func(obj interface{}) error {
 			for _, d := range obj.(cache.Deltas) {
+				if recordLatency != nil {
+					if o, ok := d.Object.(meta.Object); ok {
+						recordLatency.init(o)
+					}
+				}
 				switch d.Type {
 				case cache.Sync, cache.Added, cache.Updated:
-					obj, err := convert(d.Object)
+					obj, err := convert(d.Object.(meta.Object))
 					if err != nil {
 						return err
 					}
@@ -47,14 +54,18 @@ func DefaultProcessor(convert ToFunc, recordLatency RecordLatencyFunc) Processor
 						h.OnAdd(obj)
 					}
 					if recordLatency != nil {
-						recordLatency(d.Object.(meta.Object))
+						recordLatency.record()
 					}
 				case cache.Deleted:
 					var obj interface{}
 					obj, ok := d.Object.(cache.DeletedFinalStateUnknown)
 					if !ok {
 						var err error
-						obj, err = convert(d.Object)
+						metaObj, ok := d.Object.(meta.Object)
+						if !ok {
+							return fmt.Errorf("unexpected object %v", d.Object)
+						}
+						obj, err = convert(metaObj)
 						if err != nil && err != errPodTerminating {
 							return err
 						}
@@ -65,7 +76,7 @@ func DefaultProcessor(convert ToFunc, recordLatency RecordLatencyFunc) Processor
 					}
 					h.OnDelete(obj)
 					if !ok && recordLatency != nil {
-						recordLatency(d.Object.(meta.Object))
+						recordLatency.record()
 					}
 				}
 			}