plugin/kubernetes: fix tombstone unwrapping (#3924)

* fix tombstone unwrapping

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

plugin/kubernetes/informer_test.go

@@ -0,0 +1,111 @@
+package kubernetes
+
+import (
+	"testing"
+
+	"github.com/coredns/coredns/plugin/kubernetes/object"
+
+	api "k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/client-go/tools/cache"
+)
+
+func TestDefaultProcessor(t *testing.T) {
+	pbuild := object.DefaultProcessor(object.ToService(true), nil)
+	reh := cache.ResourceEventHandlerFuncs{}
+	idx := cache.NewIndexer(cache.DeletionHandlingMetaNamespaceKeyFunc, cache.Indexers{})
+	processor := pbuild(idx, reh)
+	testProcessor(t, processor, idx)
+}
+
+func testProcessor(t *testing.T, processor cache.ProcessFunc, idx cache.Indexer) {
+	obj := &api.Service{
+		ObjectMeta: metav1.ObjectMeta{Name: "service1", Namespace: "test1"},
+		Spec:       api.ServiceSpec{ClusterIP: "1.2.3.4", Ports: []api.ServicePort{{Port: 80}}},
+	}
+	obj2 := &api.Service{
+		ObjectMeta: metav1.ObjectMeta{Name: "service2", Namespace: "test1"},
+		Spec:       api.ServiceSpec{ClusterIP: "5.6.7.8", Ports: []api.ServicePort{{Port: 80}}},
+	}
+
+	// Add the objects
+	err := processor(cache.Deltas{
+		{Type: cache.Added, Object: obj},
+		{Type: cache.Added, Object: obj2},
+	})
+	if err != nil {
+		t.Fatalf("add failed: %v", err)
+	}
+	got, exists, err := idx.Get(obj)
+	if err != nil {
+		t.Fatalf("get added object failed: %v", err)
+	}
+	if !exists {
+		t.Fatal("added object not found in index")
+	}
+	svc, ok := got.(*object.Service)
+	if !ok {
+		t.Fatal("object in index was incorrect type")
+	}
+	if svc.ClusterIP != obj.Spec.ClusterIP {
+		t.Fatalf("expected %v, got %v", obj.Spec.ClusterIP, svc.ClusterIP)
+	}
+
+	// Update an object
+	obj.Spec.ClusterIP = "1.2.3.5"
+	err = processor(cache.Deltas{{
+		Type:   cache.Updated,
+		Object: obj,
+	}})
+	if err != nil {
+		t.Fatalf("update failed: %v", err)
+	}
+	got, exists, err = idx.Get(obj)
+	if err != nil {
+		t.Fatalf("get updated object failed: %v", err)
+	}
+	if !exists {
+		t.Fatal("updated object not found in index")
+	}
+	svc, ok = got.(*object.Service)
+	if !ok {
+		t.Fatal("object in index was incorrect type")
+	}
+	if svc.ClusterIP != obj.Spec.ClusterIP {
+		t.Fatalf("expected %v, got %v", obj.Spec.ClusterIP, svc.ClusterIP)
+	}
+
+	// Delete an object
+	err = processor(cache.Deltas{{
+		Type:   cache.Deleted,
+		Object: obj2,
+	}})
+	if err != nil {
+		t.Fatalf("delete test failed: %v", err)
+	}
+	got, exists, err = idx.Get(obj2)
+	if err != nil {
+		t.Fatalf("get deleted object failed: %v", err)
+	}
+	if exists {
+		t.Fatal("deleted object found in index")
+	}
+
+	// Delete an object via tombstone
+	key, _ := cache.MetaNamespaceKeyFunc(obj)
+	tombstone := cache.DeletedFinalStateUnknown{Key: key, Obj: svc}
+	err = processor(cache.Deltas{{
+		Type:   cache.Deleted,
+		Object: tombstone,
+	}})
+	if err != nil {
+		t.Fatalf("tombstone delete test failed: %v", err)
+	}
+	got, exists, err = idx.Get(svc)
+	if err != nil {
+		t.Fatalf("get tombstone deleted object failed: %v", err)
+	}
+	if exists {
+		t.Fatal("tombstone deleted object found in index")
+	}
+}