Support other resource types

Use the untyped k8s client to enable support for statefulsets and
replicasets as well as deployments. The typed client is retained for
usage inside pod_watcher.go.

logs/helpers.go

@@ -0,0 +1,18 @@
+package logs
+
+import "fmt"
+
+// ParseType returns an API resource type (pluralized) from a singular or
+// shortened name. If the resource is unsupported, an error will be returned.
+func ParseType(input string) (string, error) {
+	switch input {
+	case "deploy", "deployment", "deployments":
+		return "deployments", nil
+	case "sts", "statefulset", "statefulsets":
+		return "statefulsets", nil
+	case "rs", "replicaset", "replicasets":
+		return "replicasets", nil
+	default:
+		return "", fmt.Errorf(`unsupported resource: "%s". Supported resources are [deployment, statefulset, replicaset]`, input)
+	}
+}

logs/helpers_test.go

@@ -0,0 +1,68 @@
+package logs_test
+
+import (
+	"testing"
+
+	"git.netflux.io/rob/kubectl-persistent-logger/logs"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestParseKind(t *testing.T) {
+	testCases := []struct {
+		input   string
+		wantOut string
+		wantErr string
+	}{
+		{
+			input:   "deploy",
+			wantOut: "deployments",
+		},
+		{
+			input:   "deployment",
+			wantOut: "deployments",
+		},
+		{
+			input:   "deployments",
+			wantOut: "deployments",
+		},
+		{
+			input:   "sts",
+			wantOut: "statefulsets",
+		},
+		{
+			input:   "statefulset",
+			wantOut: "statefulsets",
+		},
+		{
+			input:   "statefulsets",
+			wantOut: "statefulsets",
+		},
+		{
+			input:   "rs",
+			wantOut: "replicasets",
+		},
+		{
+			input:   "replicaset",
+			wantOut: "replicasets",
+		},
+		{
+			input:   "replicasets",
+			wantOut: "replicasets",
+		},
+		{
+			input:   "foo",
+			wantErr: `unsupported resource: "foo". Supported resources are [deployment, statefulset, replicaset]`,
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.input, func(t *testing.T) {
+			result, err := logs.ParseType(tc.input)
+			if tc.wantErr != "" {
+				require.EqualError(t, err, tc.wantErr)
+			}
+			assert.Equal(t, tc.wantOut, result)
+		})
+	}
+}

logs/pod_watcher.go

@@ -40,9 +40,9 @@ func newRecoverableError(err error, podName string) *streamError {
 
 // PodWatcher consumes and merges the logs for a specified set of pods.
 type PodWatcher struct {
-	clientset     KubernetesClient
+	client        KubernetesClient
 	container     string
-	labelSelector *metav1.LabelSelector
+	labelSelector labels.Selector
 	spec          map[string]*corev1.Pod
 	status        map[string]bool
 	streamResults chan error
@@ -51,15 +51,16 @@ type PodWatcher struct {
 }
 
 // NewPodWatcher initializes a new PodWatcher.
-func NewPodWatcher(clientset KubernetesClient, container string, labelSelector *metav1.LabelSelector, dst io.Writer) PodWatcherInterface {
+func NewPodWatcher(client KubernetesClient, container string, labelSelector labels.Selector, dst io.Writer) PodWatcherInterface {
 	return &PodWatcher{
-		clientset:     clientset,
+		client:        client,
 		container:     container,
 		labelSelector: labelSelector,
 		spec:          make(map[string]*corev1.Pod),
 		status:        make(map[string]bool),
 		streamResults: make(chan error),
 		dst:           dst,
+		closeChan:     make(chan struct{}),
 	}
 }
 
@@ -77,25 +78,25 @@ func (pw *PodWatcher) WatchPods(ctx context.Context) error {
 	return err
 }
 
-// Close terminates the watcher, waiting for all logs to be consumed before
-// exiting.
+const tickerInterval = time.Millisecond * 250
+
+// Close terminates the PodWatcher.
 func (pw *PodWatcher) Close() {
 	pw.closeChan <- struct{}{}
 }
 
 func (pw *PodWatcher) watchPods(ctx context.Context, wg *sync.WaitGroup) error {
-	podsClient := pw.clientset.CoreV1().Pods(corev1.NamespaceDefault)
-	labelsMap, err := metav1.LabelSelectorAsMap(pw.labelSelector)
-	if err != nil {
-		return err
-	}
-	watcher, err := podsClient.Watch(ctx, metav1.ListOptions{LabelSelector: labels.SelectorFromSet(labelsMap).String()})
+	podsClient := pw.client.Typed.CoreV1().Pods(corev1.NamespaceDefault)
+
+	// Returns a watcher which notifies of changes in the relevant pods.
+	// We don't defer Stop() on the returned value because the sender is the
+	// Kubernetes SDK, and that may introduce a send-on-closed-channel panic.
+	watcher, err := podsClient.Watch(ctx, metav1.ListOptions{LabelSelector: pw.labelSelector.String()})
 	if err != nil {
 		return err
 	}
-	defer watcher.Stop()
 
-	ticker := time.NewTicker(time.Second)
+	ticker := time.NewTicker(tickerInterval)
 	defer ticker.Stop()
 
 	// streamErrors is never closed.
@@ -120,15 +121,14 @@ func (pw *PodWatcher) watchPods(ctx context.Context, wg *sync.WaitGroup) error {
 					pw.status[pod.Name] = true
 					wg.Add(1)
 					go func() {
-						if err := copyPodLogs(ctx, wg, pw.clientset, pod, pw.container, pw.dst); err != nil {
+						if err := copyPodLogs(ctx, wg, pw.client, pod, pw.container, pw.dst); err != nil {
 							streamErrors <- err
 						}
 					}()
 				}
 			}
 			// For any pods which no longer exist, remove the pod.
-			// TODO: check this is needed when a pod's labels change to no longer
-			// match the deployment's selector.
+			// TODO: stop the log streaming.
 			for podName := range pw.status {
 				if _, ok := pw.spec[podName]; !ok {
 					pw.removePod(podName)
@@ -146,8 +146,7 @@ func (pw *PodWatcher) watchPods(ctx context.Context, wg *sync.WaitGroup) error {
 
 		case evt, ok := <-resultChan:
 			if !ok {
-				resultChan = nil
-				continue
+				return nil
 			}
 			switch evt.Type {
 			case watch.Added, watch.Modified:
@@ -168,14 +167,15 @@ func (pw *PodWatcher) removePod(podName string) {
 	delete(pw.status, podName)
 }
 
-func copyPodLogs(ctx context.Context, wg *sync.WaitGroup, clientset KubernetesClient, pod *corev1.Pod, container string, dst io.Writer) *streamError {
+func copyPodLogs(ctx context.Context, wg *sync.WaitGroup, client KubernetesClient, pod *corev1.Pod, container string, dst io.Writer) *streamError {
 	defer wg.Done()
 
 	podLogOpts := corev1.PodLogOptions{
 		Follow:    true,
 		Container: container,
 	}
-	req := clientset.CoreV1().Pods(pod.Namespace).GetLogs(pod.Name, &podLogOpts)
+
+	req := client.Typed.CoreV1().Pods(pod.Namespace).GetLogs(pod.Name, &podLogOpts)
 	logs, err := req.Stream(ctx)
 
 	// If one container is still being created, do not treat this as a fatal error.

logs/pod_watcher_test.go

@@ -6,6 +6,7 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"log"
 	"net/http"
 	"strings"
 	"testing"
@@ -17,6 +18,7 @@ import (
 	corev1 "k8s.io/api/core/v1"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/labels"
 	"k8s.io/apimachinery/pkg/watch"
 	testclient "k8s.io/client-go/kubernetes/fake"
 	"k8s.io/client-go/kubernetes/scheme"
@@ -60,10 +62,7 @@ func (m *mockClientset) GetLogs(podName string, _ *corev1.PodLogOptions) *rest.R
 	return fakeClient.Request()
 }
 
-func TestPodWatcherClosedWatcher(t *testing.T) {
-	ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
-	defer cancel()
-
+func TestPodWatcherClose(t *testing.T) {
 	podsWatcher := watch.NewFake()
 
 	clientset := mockClientset{
@@ -73,29 +72,29 @@ func TestPodWatcherClosedWatcher(t *testing.T) {
 	}
 	clientset.PrependWatchReactor("pods", k8stest.DefaultWatchReactor(podsWatcher, nil))
 
-	client := logs.KubernetesClient{Interface: &clientset}
-	selector := metav1.LabelSelector{MatchLabels: map[string]string{"foo": "bar"}}
+	client := logs.KubernetesClient{Typed: &clientset}
+	selector := labels.SelectorFromSet(map[string]string{"foo": "bar"})
+
+	var buf bytes.Buffer
+	pw := logs.NewPodWatcher(client, "mycontainer", selector, &buf)
 
 	go func() {
-		defer podsWatcher.Stop()
-		podsWatcher.Add(&corev1.Pod{
-			ObjectMeta: metav1.ObjectMeta{Name: "foo", Namespace: "default"},
-			Status:     corev1.PodStatus{Phase: corev1.PodRunning},
-		})
+		podsWatcher.Add(&corev1.Pod{ObjectMeta: metav1.ObjectMeta{Name: "foo", Namespace: "default"}, Status: corev1.PodStatus{Phase: corev1.PodRunning}})
+		time.Sleep(time.Second)
+		// Close() should cause the watcher to return cleanly:
+		pw.Close()
 	}()
 
-	var buf bytes.Buffer
-	pw := logs.NewPodWatcher(client, "mycontainer", &selector, &buf)
+	err := pw.WatchPods(context.Background())
+	require.NoError(t, err)
 
-	// WatchPods should wait for the logs and return cleanly.
-	err := pw.WatchPods(ctx)
-	require.Equal(t, context.DeadlineExceeded, err)
 	assert.Equal(t, "[foo] it worked\n", buf.String())
 }
 
 func TestPodWatcher(t *testing.T) {
 	testCases := []struct {
 		name              string
+		podEvents         []*corev1.Pod
 		getLogsRespBody   string
 		getLogsStatusCode int
 		getLogsErr        error
@@ -103,33 +102,39 @@ func TestPodWatcher(t *testing.T) {
 		wantErr           string
 	}{
 		{
-			name:       "unexpected error getting logs",
+			name: "unexpected error getting logs",
+			podEvents: []*corev1.Pod{
+				{ObjectMeta: metav1.ObjectMeta{Name: "foo", Namespace: "default"}, Status: corev1.PodStatus{Phase: corev1.PodRunning}},
+			},
 			getLogsErr: errors.New("nope"),
 			wantOut:    nil,
 			wantErr:    "nope",
 		},
 		{
-			name:       "recoverable error getting logs",
+			name: "recoverable error getting logs",
+			podEvents: []*corev1.Pod{
+				{ObjectMeta: metav1.ObjectMeta{Name: "foo", Namespace: "default"}, Status: corev1.PodStatus{Phase: corev1.PodRunning}},
+			},
 			getLogsErr: &apierrors.StatusError{ErrStatus: metav1.Status{Message: "is waiting to start: ContainerCreating", Reason: metav1.StatusReasonBadRequest}},
 			wantOut:    nil,
-			wantErr:    context.DeadlineExceeded.Error(),
 		},
 		{
-			name:              "success",
+			name: "success",
+			podEvents: []*corev1.Pod{
+				{ObjectMeta: metav1.ObjectMeta{Name: "foo", Namespace: "default"}, Status: corev1.PodStatus{Phase: corev1.PodRunning}},
+				{ObjectMeta: metav1.ObjectMeta{Name: "bar", Namespace: "default"}, Status: corev1.PodStatus{Phase: corev1.PodRunning}},
+				{ObjectMeta: metav1.ObjectMeta{Name: "baz", Namespace: "default"}, Status: corev1.PodStatus{Phase: corev1.PodPending}},
+			},
 			getLogsRespBody:   "some logs",
 			getLogsStatusCode: http.StatusOK,
 			wantOut:           []string{"[foo] some logs", "[bar] some logs"},
-			wantErr:           context.DeadlineExceeded.Error(),
 		},
 	}
 
 	for _, tc := range testCases {
 		t.Run(tc.name, func(t *testing.T) {
-			ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
-			defer cancel()
-
 			podsWatcher := watch.NewFake()
-			defer podsWatcher.Stop()
+			defer log.Println("exiting test func")
 
 			clientset := mockClientset{
 				getLogsRespBody:   tc.getLogsRespBody,
@@ -139,42 +144,33 @@ func TestPodWatcher(t *testing.T) {
 			}
 			clientset.PrependWatchReactor("pods", k8stest.DefaultWatchReactor(podsWatcher, nil))
 
-			client := logs.KubernetesClient{Interface: &clientset}
-			selector := metav1.LabelSelector{MatchLabels: map[string]string{"foo": "bar"}}
+			client := logs.KubernetesClient{Typed: &clientset}
+			selector := labels.SelectorFromSet(map[string]string{"foo": "bar"})
+
+			var buf bytes.Buffer
+			pw := logs.NewPodWatcher(client, "mycontainer", selector, &buf)
 
 			go func() {
-				pods := []*corev1.Pod{
-					{
-						ObjectMeta: metav1.ObjectMeta{Name: "foo", Namespace: "default"},
-						Status:     corev1.PodStatus{Phase: corev1.PodRunning},
-					},
-					{
-						ObjectMeta: metav1.ObjectMeta{Name: "bar", Namespace: "default"},
-						Status:     corev1.PodStatus{Phase: corev1.PodRunning},
-					},
-					{
-						ObjectMeta: metav1.ObjectMeta{Name: "baz", Namespace: "default"},
-						Status:     corev1.PodStatus{Phase: corev1.PodPending},
-					},
-				}
-				for _, pod := range pods {
+				for _, pod := range tc.podEvents {
 					podsWatcher.Add(pod)
-					time.Sleep(time.Millisecond * 250)
+					time.Sleep(time.Millisecond * 500)
 				}
+				pw.Close()
 			}()
 
-			var buf bytes.Buffer
-			pw := logs.NewPodWatcher(client, "mycontainer", &selector, &buf)
-
-			err := pw.WatchPods(ctx)
+			err := pw.WatchPods(context.Background())
 
 			if tc.wantErr == "" {
 				require.NoError(t, err)
 			} else {
+				require.Error(t, err)
 				require.Contains(t, err.Error(), tc.wantErr)
 			}
+
 			if tc.wantOut != nil {
-				assert.ElementsMatch(t, tc.wantOut, bufToLines(&buf))
+				lines := bufToLines(&buf)
+				require.Len(t, lines, len(tc.wantOut))
+				assert.ElementsMatch(t, tc.wantOut, lines)
 			}
 		})
 	}

logs/watcher.go

@@ -8,17 +8,23 @@ import (
 	"sync"
 	"time"
 
-	appsv1 "k8s.io/api/apps/v1"
 	corev1 "k8s.io/api/core/v1"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/labels"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/apimachinery/pkg/watch"
+	"k8s.io/client-go/dynamic"
 	"k8s.io/client-go/kubernetes"
 )
 
-// KubernetesClient wraps a Kubernetes clientset.
+// KubernetesClient provides both typed and untyped interfaces to the
+// Kubernetes API.
 type KubernetesClient struct {
-	kubernetes.Interface
+	Typed   kubernetes.Interface
+	Untyped dynamic.Interface
 }
 
 // concurrentWriter implements an io.Writer that can be safely written to from
@@ -42,16 +48,24 @@ type PodWatcherInterface interface {
 }
 
 // PodWatcherFunc builds a PodWatcher.
-type PodWatcherFunc func(KubernetesClient, string, *metav1.LabelSelector, io.Writer) PodWatcherInterface
+type PodWatcherFunc func(KubernetesClient, string, labels.Selector, io.Writer) PodWatcherInterface
+
+// WatcherParams defines the input parameters of a Watcher.
+type WatcherParams struct {
+	Name        string
+	Type        string
+	Namespace   string
+	Container   string
+	StrictExist bool
+}
 
 // Watcher watches a deployment and tails the logs for its currently active
 // pods.
 type Watcher struct {
-	deployName     string
-	container      string
-	strictExist    bool
-	clientset      KubernetesClient
-	deployment     *appsv1.Deployment
+	params         WatcherParams
+	client         KubernetesClient
+	resourceUID    types.UID
+	podSelector    labels.Selector
 	podWatcher     PodWatcherInterface
 	podWatcherFunc PodWatcherFunc
 	errChan        chan error
@@ -59,12 +73,10 @@ type Watcher struct {
 }
 
 // NewWatcher creates a new Watcher.
-func NewWatcher(deployName string, container string, strictExist bool, clientset KubernetesClient, podWatcherFunc PodWatcherFunc, dst io.Writer) *Watcher {
+func NewWatcher(params WatcherParams, client KubernetesClient, podWatcherFunc PodWatcherFunc, dst io.Writer) *Watcher {
 	return &Watcher{
-		deployName:     deployName,
-		container:      container,
-		strictExist:    strictExist,
-		clientset:      clientset,
+		params:         params,
+		client:         client,
 		podWatcherFunc: podWatcherFunc,
 		errChan:        make(chan error),
 		dst:            &concurrentWriter{w: dst},
@@ -73,30 +85,35 @@ func NewWatcher(deployName string, container string, strictExist bool, clientset
 
 // Watch watches a deployment.
 func (w *Watcher) Watch(ctx context.Context) error {
-	deploymentsClient := w.clientset.AppsV1().Deployments(corev1.NamespaceDefault)
+	ns := w.params.Namespace
+	if ns == "" {
+		ns = corev1.NamespaceDefault
+	}
 
-	// Check if the deployment exists before we commence watching, to allow us to
-	// return an error if needed.
-	_, err := deploymentsClient.Get(ctx, w.deployName, metav1.GetOptions{})
-	var statusErr *apierrors.StatusError
-	if errors.As(err, &statusErr) && statusErr.Status().Reason == metav1.StatusReasonNotFound {
-		if w.strictExist {
-			return err
-		}
-		log.Printf(`deployment "%s" does not exist, waiting`, w.deployName)
+	// Supported resource types are deployments, statefulsets and replicasets
+	// (all apps/v1).
+	resourceID := schema.GroupVersionResource{
+		Resource: w.params.Type,
+		Group:    "apps",
+		Version:  "v1",
+	}
+
+	if err := w.checkResourceExists(ctx, ns, resourceID); err != nil {
+		return err
 	}
 
-	opts := metav1.ListOptions{Watch: true, FieldSelector: "metadata.name=" + w.deployName}
-	deploymentsWatcher, err := deploymentsClient.Watch(ctx, opts)
+	opts := metav1.ListOptions{Watch: true, FieldSelector: "metadata.name=" + w.params.Name}
+	watcher, err := w.client.Untyped.Resource(resourceID).Namespace(ns).Watch(ctx, opts)
 	if err != nil {
 		return err
 	}
-	defer deploymentsWatcher.Stop()
+
+	defer watcher.Stop()
 
 	ticker := time.NewTicker(time.Second)
 	defer ticker.Stop()
 
-	resultChan := deploymentsWatcher.ResultChan()
+	resultChan := watcher.ResultChan()
 	for {
 		select {
 		case evt, ok := <-resultChan:
@@ -106,8 +123,19 @@ func (w *Watcher) Watch(ctx context.Context) error {
 			}
 			switch evt.Type {
 			case watch.Added, watch.Modified:
-				deployment := evt.Object.(*appsv1.Deployment)
-				w.addDeployment(ctx, deployment)
+				resource := evt.Object.(*unstructured.Unstructured)
+				uid := resource.GetUID()
+				// TODO: handle matchExpressions
+				selectorAsMap, ok, err := unstructured.NestedStringMap(resource.Object, "spec", "selector", "matchLabels")
+				if !ok || err != nil {
+					// matchLabels don't exist or cannot be parsed.
+					// Should this be fatal?
+					log.Printf("warning: unable to parse matchLabels: ok = %t, err = %v", ok, err)
+					continue
+				}
+				selector := labels.SelectorFromSet(selectorAsMap)
+				w.addDeployment(ctx, uid, selector)
+
 			case watch.Deleted:
 				w.removeDeployment()
 			}
@@ -119,20 +147,31 @@ func (w *Watcher) Watch(ctx context.Context) error {
 	}
 }
 
-func (w *Watcher) addDeployment(ctx context.Context, deployment *appsv1.Deployment) {
-	if w.deployment != nil && w.deployment.UID == deployment.UID {
+func (w *Watcher) checkResourceExists(ctx context.Context, namespace string, resourceID schema.GroupVersionResource) error {
+	_, err := w.client.Untyped.Resource(resourceID).Namespace(namespace).Get(ctx, w.params.Name, metav1.GetOptions{})
+	var statusErr *apierrors.StatusError
+	if !w.params.StrictExist && errors.As(err, &statusErr) && statusErr.Status().Reason == metav1.StatusReasonNotFound {
+		log.Printf(`%s "%s" does not exist, waiting`, resourceID.Resource, w.params.Name)
+		return nil
+	}
+	return err
+}
+
+func (w *Watcher) addDeployment(ctx context.Context, resourceUID types.UID, podSelector labels.Selector) {
+	if w.resourceUID == resourceUID {
 		return
 	}
 
 	w.removeDeployment()
 
-	log.Println("[DeploymentWatcher] add deployment")
+	log.Println("[DeploymentWatcher] add podWatcher")
 
-	w.deployment = deployment
+	w.resourceUID = resourceUID
+	w.podSelector = podSelector
 	w.podWatcher = w.podWatcherFunc(
-		w.clientset,
-		w.container,
-		deployment.Spec.Selector,
+		w.client,
+		w.params.Container,
+		w.podSelector,
 		w.dst,
 	)
 
@@ -145,9 +184,10 @@ func (w *Watcher) addDeployment(ctx context.Context, deployment *appsv1.Deployme
 
 func (w *Watcher) removeDeployment() {
 	if w.podWatcher != nil {
-		log.Println("[DeploymentWatcher] remove deployment")
+		log.Println("[DeploymentWatcher] remove podWatcher")
 		w.podWatcher.Close()
 		w.podWatcher = nil
 	}
-	w.deployment = nil
+	w.resourceUID = ""
+	w.podSelector = nil
 }

logs/watcher_test.go

@@ -12,10 +12,14 @@ import (
 	"git.netflux.io/rob/kubectl-persistent-logger/logs"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
-	appsv1 "k8s.io/api/apps/v1"
 	corev1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/labels"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/types"
 	"k8s.io/apimachinery/pkg/watch"
+	dynamicclient "k8s.io/client-go/dynamic/fake"
 	testclient "k8s.io/client-go/kubernetes/fake"
 	k8stest "k8s.io/client-go/testing"
 )
@@ -26,17 +30,28 @@ func (m *mockPodWatcher) WatchPods(ctx context.Context) error { return m.err }
 func (m *mockPodWatcher) Close()                              {}
 
 func mockPodwatcherFunc(err error) logs.PodWatcherFunc {
-	return func(logs.KubernetesClient, string, *metav1.LabelSelector, io.Writer) logs.PodWatcherInterface {
+	return func(logs.KubernetesClient, string, labels.Selector, io.Writer) logs.PodWatcherInterface {
 		return &mockPodWatcher{err: err}
 	}
 }
 
-func TestWatcherAllowNonExistent(t *testing.T) {
-	clientset := testclient.NewSimpleClientset()
+func buildDeployment(t *testing.T, name string) *unstructured.Unstructured {
+	deployment := new(unstructured.Unstructured)
+	deployment.SetAPIVersion("v1")
+	deployment.SetKind("deployment")
+	deployment.SetName("mydeployment")
+	deployment.SetNamespace("default")
+	deployment.SetUID(types.UID("foo"))
+	require.NoError(t, unstructured.SetNestedField(deployment.Object, map[string]any{"app": "myapp"}, "spec", "selector", "matchLabels"))
+	return deployment
+}
+
+func TestWatcherStrictExist(t *testing.T) {
+	client := logs.KubernetesClient{Untyped: dynamicclient.NewSimpleDynamicClient(runtime.NewScheme())}
 
 	var buf bytes.Buffer
-	client := logs.KubernetesClient{Interface: clientset}
-	watcher := logs.NewWatcher("mydeployment", "mycontainer", true, client, mockPodwatcherFunc(nil), &buf)
+	params := logs.WatcherParams{Name: "mydeployment", Type: "deployments", Namespace: "default", StrictExist: true}
+	watcher := logs.NewWatcher(params, client, mockPodwatcherFunc(nil), &buf)
 
 	err := watcher.Watch(context.Background())
 	assert.EqualError(t, err, `deployments.apps "mydeployment" not found`)
@@ -44,19 +59,20 @@ func TestWatcherAllowNonExistent(t *testing.T) {
 
 func TestWatcherPodWatcherError(t *testing.T) {
 	deploymentsWatcher := watch.NewFake()
-	clientset := testclient.NewSimpleClientset(
-		&appsv1.Deployment{ObjectMeta: metav1.ObjectMeta{Name: "mydeployment", Namespace: "default"}},
-	)
-	clientset.PrependWatchReactor("deployments", k8stest.DefaultWatchReactor(deploymentsWatcher, nil))
+
+	untypedClient := dynamicclient.NewSimpleDynamicClient(runtime.NewScheme())
+	untypedClient.PrependWatchReactor("deployments", k8stest.DefaultWatchReactor(deploymentsWatcher, nil))
+	client := logs.KubernetesClient{Untyped: untypedClient}
 
 	var buf bytes.Buffer
-	client := logs.KubernetesClient{Interface: clientset}
 	wantErr := errors.New("foo")
-	watcher := logs.NewWatcher("mydeployment", "mycontainer", true, client, mockPodwatcherFunc(wantErr), &buf)
+	params := logs.WatcherParams{Name: "mydeployment", Type: "deployments", Namespace: "default"}
+	watcher := logs.NewWatcher(params, client, mockPodwatcherFunc(wantErr), &buf)
 
 	go func() {
 		defer deploymentsWatcher.Stop()
-		deployment := &appsv1.Deployment{ObjectMeta: metav1.ObjectMeta{Name: "mydeployment", Namespace: "default"}}
+
+		deployment := buildDeployment(t, "mydeployment")
 		deploymentsWatcher.Add(deployment)
 	}()
 
@@ -66,15 +82,17 @@ func TestWatcherPodWatcherError(t *testing.T) {
 
 func TestWatcherClosedChannel(t *testing.T) {
 	deploymentsWatcher := watch.NewFake()
-	clientset := testclient.NewSimpleClientset(
-		&appsv1.Deployment{ObjectMeta: metav1.ObjectMeta{Name: "mydeployment", Namespace: "default"}},
-	)
-	clientset.PrependWatchReactor("deployments", k8stest.DefaultWatchReactor(deploymentsWatcher, nil))
+
+	untypedClient := dynamicclient.NewSimpleDynamicClient(runtime.NewScheme())
+	untypedClient.PrependWatchReactor("deployments", k8stest.DefaultWatchReactor(deploymentsWatcher, nil))
+	client := logs.KubernetesClient{Untyped: untypedClient}
 
 	var buf bytes.Buffer
-	client := logs.KubernetesClient{Interface: clientset}
-	watcher := logs.NewWatcher("mydeployment", "mycontainer", true, client, nil, &buf)
-	go deploymentsWatcher.Stop()
+	params := logs.WatcherParams{Name: "mydeployment", Type: "deployments", Namespace: "default"}
+	watcher := logs.NewWatcher(params, client, nil, &buf)
+	// Immediately stop the watcher, which closes the ResultChan.
+	// This should be expected to be handled.
+	deploymentsWatcher.Stop()
 
 	ctx, cancel := context.WithTimeout(context.Background(), time.Millisecond*500)
 	defer cancel()
@@ -90,31 +108,25 @@ func TestWatcherWithPodWatcher(t *testing.T) {
 
 	deploymentsWatcher := watch.NewFake()
 	defer deploymentsWatcher.Stop()
+
 	podsWatcher := watch.NewFake()
 	defer podsWatcher.Stop()
 
-	clientset := testclient.NewSimpleClientset()
-	clientset.PrependWatchReactor("pods", k8stest.DefaultWatchReactor(podsWatcher, nil))
-	clientset.PrependWatchReactor("deployments", k8stest.DefaultWatchReactor(deploymentsWatcher, nil))
+	typedClient := testclient.NewSimpleClientset()
+	typedClient.PrependWatchReactor("pods", k8stest.DefaultWatchReactor(podsWatcher, nil))
+	untypedClient := dynamicclient.NewSimpleDynamicClient(runtime.NewScheme())
+	untypedClient.PrependWatchReactor("deployments", k8stest.DefaultWatchReactor(deploymentsWatcher, nil))
+	client := logs.KubernetesClient{Typed: typedClient, Untyped: untypedClient}
 
 	go func() {
-		deployment := &appsv1.Deployment{ObjectMeta: metav1.ObjectMeta{Name: "mydeployment", Namespace: "default"}}
+		deployment := buildDeployment(t, "mydeployment")
 		deploymentsWatcher.Add(deployment)
 		time.Sleep(time.Millisecond * 250)
 
 		pods := []*corev1.Pod{
-			{
-				ObjectMeta: metav1.ObjectMeta{Name: "foo", Namespace: "default"},
-				Status:     corev1.PodStatus{Phase: corev1.PodRunning},
-			},
-			{
-				ObjectMeta: metav1.ObjectMeta{Name: "bar", Namespace: "default"},
-				Status:     corev1.PodStatus{Phase: corev1.PodRunning},
-			},
-			{
-				ObjectMeta: metav1.ObjectMeta{Name: "baz", Namespace: "default"},
-				Status:     corev1.PodStatus{Phase: corev1.PodPending},
-			},
+			{ObjectMeta: metav1.ObjectMeta{Name: "foo", Namespace: "default"}, Status: corev1.PodStatus{Phase: corev1.PodRunning}},
+			{ObjectMeta: metav1.ObjectMeta{Name: "bar", Namespace: "default"}, Status: corev1.PodStatus{Phase: corev1.PodRunning}},
+			{ObjectMeta: metav1.ObjectMeta{Name: "baz", Namespace: "default"}, Status: corev1.PodStatus{Phase: corev1.PodPending}},
 		}
 		for _, pod := range pods {
 			podsWatcher.Add(pod)
@@ -123,14 +135,14 @@ func TestWatcherWithPodWatcher(t *testing.T) {
 	}()
 
 	var buf bytes.Buffer
-	client := logs.KubernetesClient{Interface: clientset}
-	watcher := logs.NewWatcher("mydeployment", "mycontainer", false, client, logs.NewPodWatcher, &buf)
+	params := logs.WatcherParams{Name: "mydeployment", Type: "deployments", Namespace: "default"}
+	watcher := logs.NewWatcher(params, client, logs.NewPodWatcher, &buf)
 
 	err := watcher.Watch(ctx)
 	require.EqualError(t, err, context.DeadlineExceeded.Error())
 	lines := bufToLines(&buf)
-	assert.Len(t, lines, 2)
-	assert.ElementsMatch(t, []string{"[foo] fake logs", "[bar] fake logs"}, bufToLines(&buf))
+	require.Len(t, lines, 2)
+	assert.ElementsMatch(t, []string{"[foo] fake logs", "[bar] fake logs"}, lines)
 }
 
 func bufToLines(buf *bytes.Buffer) []string {

main.go

@@ -7,21 +7,43 @@ import (
 	"os"
 
 	"git.netflux.io/rob/kubectl-persistent-logger/logs"
+	"k8s.io/client-go/dynamic"
 	"k8s.io/client-go/kubernetes"
 	clientconfig "sigs.k8s.io/controller-runtime/pkg/client/config"
 )
 
 func main() {
 	var (
-		deployName  *string
-		container   *string
-		strictExist *bool
+		container   string
+		strictExist bool
 	)
-	deployName = flag.String("deployment", "", "name of a deployment to monitor")
-	container = flag.String("container", "", "name of a specific container")
-	strictExist = flag.Bool("strict-exist", false, "require deployment to exist on launch")
+
+	flag.StringVar(&container, "container", "", "name of a specific container")
+	flag.BoolVar(&strictExist, "strict", false, "require deployment to exist on launch")
 	flag.Parse()
 
+	var params logs.WatcherParams
+
+	switch len(flag.Args()) {
+	case 1:
+		// TODO: handle type/name style
+		flag.Usage()
+		os.Exit(1)
+	case 2:
+		kind, err := logs.ParseType(flag.Arg(0))
+		if err != nil {
+			log.Fatal(err)
+		}
+		params = logs.WatcherParams{
+			Type:      kind,
+			Name:      flag.Arg(1),
+			Namespace: "default",
+		}
+	default:
+		flag.Usage()
+		os.Exit(1)
+	}
+
 	cfg, err := clientconfig.GetConfig()
 	if err != nil {
 		log.Fatal(err)
@@ -32,12 +54,15 @@ func main() {
 		log.Fatal(err)
 	}
 
+	dynamicclient, err := dynamic.NewForConfig(cfg)
+	if err != nil {
+		log.Fatal(err)
+	}
+
 	ctx := context.Background()
 	watcher := logs.NewWatcher(
-		*deployName,
-		*container,
-		*strictExist,
-		logs.KubernetesClient{Interface: clientset},
+		params,
+		logs.KubernetesClient{Typed: clientset, Untyped: dynamicclient},
 		logs.NewPodWatcher,
 		os.Stdout,
 	)