add ListKeys method to Store

pkg/client/cache/store.go

@@ -37,6 +37,7 @@ type Store interface {
 	Update(obj interface{}) error
 	Delete(obj interface{}) error
 	List() []interface{}
+	ListKeys() []string
 	Get(obj interface{}) (item interface{}, exists bool, err error)
 	GetByKey(key string) (item interface{}, exists bool, err error)
 
@@ -195,6 +196,18 @@ func (c *cache) List() []interface{} {
 	return list
 }
 
+// ListKeys returns a list of all the keys of the objects currently
+// in the cache.
+func (c *cache) ListKeys() []string {
+	c.lock.RLock()
+	defer c.lock.RUnlock()
+	list := make([]string, 0, len(c.items))
+	for key := range c.items {
+		list = append(list, key)
+	}
+	return list
+}
+
 // Index returns a list of items that match on the index function
 // Index is thread-safe so long as you treat all items as immutable
 func (c *cache) Index(indexName string, obj interface{}) ([]interface{}, error) {

pkg/client/cache/undelta_store.go

@@ -49,6 +49,7 @@ func (u *UndeltaStore) Add(obj interface{}) error {
 	u.PushFunc(u.ActualStore.List())
 	return nil
 }
+
 func (u *UndeltaStore) Update(obj interface{}) error {
 	if err := u.ActualStore.Update(obj); err != nil {
 		return err
@@ -56,6 +57,7 @@ func (u *UndeltaStore) Update(obj interface{}) error {
 	u.PushFunc(u.ActualStore.List())
 	return nil
 }
+
 func (u *UndeltaStore) Delete(obj interface{}) error {
 	if err := u.ActualStore.Delete(obj); err != nil {
 		return err
@@ -63,15 +65,23 @@ func (u *UndeltaStore) Delete(obj interface{}) error {
 	u.PushFunc(u.ActualStore.List())
 	return nil
 }
+
 func (u *UndeltaStore) List() []interface{} {
 	return u.ActualStore.List()
 }
+
+func (u *UndeltaStore) ListKeys() []string {
+	return u.ActualStore.ListKeys()
+}
+
 func (u *UndeltaStore) Get(obj interface{}) (item interface{}, exists bool, err error) {
 	return u.ActualStore.Get(obj)
 }
+
 func (u *UndeltaStore) GetByKey(key string) (item interface{}, exists bool, err error) {
 	return u.ActualStore.GetByKey(key)
 }
+
 func (u *UndeltaStore) Replace(list []interface{}) error {
 	if err := u.ActualStore.Replace(list); err != nil {
 		return err