add controllers that have zero pods (#41)

pkg/controller/controller.go

@@ -28,6 +28,23 @@ import (
 	"github.com/fairwindsops/controller-utils/pkg/log"
 )
 
+type knownKind struct {
+	kind string
+	apiVersion string
+}
+
+var knownKinds = []knownKind{{
+	"Deployment", "apps/v1",
+}, {
+	"CronJob", "batch/v1",
+}, {
+	"Job", "batch/v1",
+}, {
+	"DaemonSet", "apps/v1",
+}, {
+	"StatefulSet", "apps/v1",
+}}
+
 // Workload represents a workload in the cluster. It contains the top level object and all of the pods.
 type Workload struct {
 	TopController unstructured.Unstructured
@@ -48,14 +65,34 @@ func getAllPods(ctx context.Context, dynamicClient dynamic.Interface, restMapper
 	return pods.Items, nil
 }
 
+func prepCacheWithKnownControllers(ctx context.Context, dynamicClient dynamic.Interface, restMapper meta.RESTMapper, namespace string, objectCache map[string]unstructured.Unstructured) error {
+	for _, kind := range knownKinds {
+		err := cacheAllObjectsOfKind(ctx, kind.apiVersion, kind.kind, namespace, dynamicClient, restMapper, objectCache)
+		if err != nil {
+			log.GetLogger().V(3).Info("Unable to prime cache with objects of kind " + kind.kind)
+		}
+	}
+	return nil
+}
+
 // GetAllTopControllers returns the highest level owning object of all pods. If a namespace is provided than this is limited to that namespace.
 func GetAllTopControllers(ctx context.Context, dynamicClient dynamic.Interface, restMapper meta.RESTMapper, namespace string) ([]Workload, error) {
+	workloadMap := map[string]Workload{}
+	objectCache := map[string]unstructured.Unstructured{}
+	err := prepCacheWithKnownControllers(ctx, dynamicClient, restMapper, namespace, objectCache)
+	if err != nil {
+		return nil, err
+	}
+	for _, controller := range objectCache {
+		key := getControllerKey(controller)
+		workloadMap[key] = Workload{
+			TopController: controller,
+		}
+	}
 	pods, err := getAllPods(ctx, dynamicClient, restMapper, namespace)
 	if err != nil {
 		return nil, err
 	}
-	workloadMap := map[string]Workload{}
-	objectCache := map[string]unstructured.Unstructured{}
 	// TODO avoid cycling over multiple pods with the same parent
 	for _, pod := range pods {
 		controller, err := GetTopController(ctx, dynamicClient, restMapper, pod, objectCache)
@@ -157,6 +194,7 @@ func GetTopController(ctx context.Context, dynamicClient dynamic.Interface, rest
 }
 
 func cacheAllObjectsOfKind(ctx context.Context, apiVersion, kind, namespace string, dynamicClient dynamic.Interface, restMapper meta.RESTMapper, objectCache map[string]unstructured.Unstructured) error {
+	fmt.Println("cache all", apiVersion, kind)
 	fqKind := schema.FromAPIVersionAndKind(apiVersion, kind)
 	mapping, err := restMapper.RESTMapping(fqKind.GroupKind(), fqKind.Version)
 	if err != nil {

pkg/controller/controller_test.go

@@ -108,6 +108,16 @@ func setupFakeData(t *testing.T) (dynamicPkg.Interface, meta.RESTMapper, unstruc
 			},
 		},
 	}
+	depNoPods := unstructured.Unstructured{
+		Object: map[string]interface{}{
+			"apiVersion": "apps/v1",
+			"kind":       "Deployment",
+			"metadata": map[string]interface{}{
+				"name":      "dep-no-pods",
+				"namespace": "test",
+			},
+		},
+	}
 	dynamic := fake.NewSimpleDynamicClientWithCustomListKinds(runtime.NewScheme(),
 		map[schema.GroupVersionResource]string{
 			{Group: "apps", Version: "v1", Resource: "replicasets"}: "ReplicaSetList",
@@ -129,6 +139,8 @@ func setupFakeData(t *testing.T) (dynamicPkg.Interface, meta.RESTMapper, unstruc
 	assert.NoError(t, err)
 	_, err = dynamic.Resource(mapping.Resource).Namespace("test").Create(context.TODO(), &dep, metav1.CreateOptions{})
 	assert.NoError(t, err)
+	_, err = dynamic.Resource(mapping.Resource).Namespace("test").Create(context.TODO(), &depNoPods, metav1.CreateOptions{})
+	assert.NoError(t, err)
 	return dynamic, restMapper, pod, rs, dep, pod2
 }
 
@@ -151,8 +163,8 @@ func TestGetAllTopControllers(t *testing.T) {
 	dynamic, restMapper, _, _, _, _ := setupFakeData(t)
 	controllers, err := GetAllTopControllers(context.TODO(), dynamic, restMapper, "")
 	assert.NoError(t, err)
-	assert.Equal(t, 2, len(controllers))
+	assert.Equal(t, 3, len(controllers))
 	controllers, err = GetAllTopControllers(context.TODO(), dynamic, restMapper, "test")
 	assert.NoError(t, err)
-	assert.Equal(t, 1, len(controllers))
+	assert.Equal(t, 2, len(controllers))
 }