[cozystack-controller] Ancestor tracking webhook

Many resources created as part of managed apps in cozystack (pods,
secrets, etc) do not carry predictable labels that unambiguously
indicate which app originally triggered their creation. Some resources
are managed by controllers and other custom resources and this
indirection can lead to loss of information. Other controllers sometimes
simply do not allow setting labels on controlled resources and the
latter do not inherit labels from the owner. This patch implements a
webhook that sidesteps this problem with a universal solution. On
creation of a pod/secret/PVC etc it walks through the owner references
until a HelmRelease is found that can be matched with a managed app
dynamically registered in the Cozystack API server. The pod is mutated
with labels identifying the managed app.

```release-note
[cozystack-controller] Add a mutating webhook to identify the Cozystack
managed app that ultimately owns low-level resources created in the
cluster and label these resources with a reference to said app.
```

Signed-off-by: Timofei Larkin <lllamnyp@gmail.com>

cmd/cozystack-controller/main.go

@@ -38,6 +38,7 @@ import (
 
 	cozystackiov1alpha1 "github.com/cozystack/cozystack/api/v1alpha1"
 	"github.com/cozystack/cozystack/internal/controller"
+	lcw "github.com/cozystack/cozystack/internal/lineagecontrollerwebhook"
 	"github.com/cozystack/cozystack/internal/telemetry"
 
 	helmv2 "github.com/fluxcd/helm-controller/api/v2"
@@ -214,6 +215,20 @@ func main() {
 		os.Exit(1)
 	}
 
+	// special one that's both a webhook and a reconciler
+	lineageControllerWebhook := &lcw.LineageControllerWebhook{
+		Client: mgr.GetClient(),
+		Scheme: mgr.GetScheme(),
+	}
+	if err := lineageControllerWebhook.SetupWithManagerAsController(mgr); err != nil {
+		setupLog.Error(err, "unable to setup controller", "controller", "LineageController")
+		os.Exit(1)
+	}
+	if err := lineageControllerWebhook.SetupWithManagerAsWebhook(mgr); err != nil {
+		setupLog.Error(err, "unable to setup webhook", "webhook", "LineageWebhook")
+		os.Exit(1)
+	}
+
 	// +kubebuilder:scaffold:builder
 
 	if err := mgr.AddHealthzCheck("healthz", healthz.Ping); err != nil {

internal/lineagecontrollerwebhook/config.go

@@ -0,0 +1,40 @@
+package lineagecontrollerwebhook
+
+import (
+	"fmt"
+
+	helmv2 "github.com/fluxcd/helm-controller/api/v2"
+)
+
+type chartRef struct {
+	repo  string
+	chart string
+}
+
+type appRef struct {
+	groupVersion string
+	kind         string
+	prefix       string
+}
+
+type runtimeConfig struct {
+	chartAppMap map[chartRef]appRef
+}
+
+func (l *LineageControllerWebhook) initConfig() {
+	l.initOnce.Do(func() {
+		if l.config.Load() == nil {
+			l.config.Store(&runtimeConfig{chartAppMap: make(map[chartRef]appRef)})
+		}
+	})
+}
+
+func (l *LineageControllerWebhook) Map(hr *helmv2.HelmRelease) (string, string, string, error) {
+	cfg := l.config.Load().(*runtimeConfig).chartAppMap
+	s := &hr.Spec.Chart.Spec
+	val, ok := cfg[chartRef{s.SourceRef.Name, s.Chart}]
+	if !ok {
+		return "", "", "", fmt.Errorf("cannot map helm release %s/%s to dynamic app", hr.Namespace, hr.Name)
+	}
+	return val.groupVersion, val.kind, val.prefix, nil
+}

internal/lineagecontrollerwebhook/controller.go

@@ -0,0 +1,42 @@
+package lineagecontrollerwebhook
+
+import (
+	"context"
+
+	cozyv1alpha1 "github.com/cozystack/cozystack/api/v1alpha1"
+	ctrl "sigs.k8s.io/controller-runtime"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+	"sigs.k8s.io/controller-runtime/pkg/log"
+)
+
+// +kubebuilder:rbac:groups=cozystack.io,resources=cozystackresourcedefinitions,verbs=list;watch
+
+func (c *LineageControllerWebhook) SetupWithManagerAsController(mgr ctrl.Manager) error {
+	return ctrl.NewControllerManagedBy(mgr).
+		For(&cozyv1alpha1.CozystackResourceDefinition{}).
+		Complete(c)
+}
+
+func (c *LineageControllerWebhook) Reconcile(ctx context.Context, req ctrl.Request) (ctrl.Result, error) {
+	l := log.FromContext(ctx)
+	crds := &cozyv1alpha1.CozystackResourceDefinitionList{}
+	if err := c.List(ctx, crds, &client.ListOptions{Namespace: "cozy-system"}); err != nil {
+		l.Error(err, "failed reading CozystackResourceDefinitions")
+		return ctrl.Result{}, err
+	}
+	newConfig := make(map[chartRef]appRef)
+	for _, crd := range crds.Items {
+		k := chartRef{
+			crd.Spec.Release.Chart.SourceRef.Name,
+			crd.Spec.Release.Chart.Name,
+		}
+		newRef := appRef{"apps.cozystack.io/v1alpha1", crd.Spec.Application.Kind, crd.Spec.Release.Prefix}
+		if oldRef, exists := newConfig[k]; exists {
+			l.Info("duplicate chart mapping detected; ignoring subsequent entry", "key", k, "retained value", oldRef, "ignored value", newRef)
+			continue
+		}
+		newConfig[k] = newRef
+	}
+	c.config.Store(&runtimeConfig{newConfig})
+	return ctrl.Result{}, nil
+}

internal/lineagecontrollerwebhook/types.go

@@ -0,0 +1,23 @@
+package lineagecontrollerwebhook
+
+import (
+	"sync"
+	"sync/atomic"
+
+	"k8s.io/apimachinery/pkg/api/meta"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/client-go/dynamic"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+	"sigs.k8s.io/controller-runtime/pkg/webhook/admission"
+)
+
+// +kubebuilder:webhook:path=/mutate-lineage,mutating=true,failurePolicy=Fail,sideEffects=None,groups="",resources=pods,secrets,services,persistentvolumeclaims,verbs=create;update,versions=v1,name=mlineage.cozystack.io,admissionReviewVersions={v1}
+type LineageControllerWebhook struct {
+	client.Client
+	Scheme    *runtime.Scheme
+	decoder   admission.Decoder
+	dynClient dynamic.Interface
+	mapper    meta.RESTMapper
+	config    atomic.Value
+	initOnce  sync.Once
+}

internal/lineagecontrollerwebhook/webhook.go

@@ -0,0 +1,166 @@
+package lineagecontrollerwebhook
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+
+	"github.com/cozystack/cozystack/pkg/lineage"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/client-go/discovery"
+	"k8s.io/client-go/discovery/cached/memory"
+	"k8s.io/client-go/dynamic"
+	"k8s.io/client-go/rest"
+	"k8s.io/client-go/restmapper"
+	ctrl "sigs.k8s.io/controller-runtime"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+	"sigs.k8s.io/controller-runtime/pkg/log"
+	"sigs.k8s.io/controller-runtime/pkg/webhook/admission"
+)
+
+var (
+	NoAncestors       = fmt.Errorf("no managed apps found in lineage")
+	AncestryAmbiguous = fmt.Errorf("object ancestry is ambiguous")
+)
+
+// SetupWithManager registers the handler with the webhook server.
+func (h *LineageControllerWebhook) SetupWithManagerAsWebhook(mgr ctrl.Manager) error {
+	cfg := rest.CopyConfig(mgr.GetConfig())
+
+	var err error
+	h.dynClient, err = dynamic.NewForConfig(cfg)
+	if err != nil {
+		return err
+	}
+
+	discoClient, err := discovery.NewDiscoveryClientForConfig(cfg)
+	if err != nil {
+		return err
+	}
+
+	cachedDisco := memory.NewMemCacheClient(discoClient)
+	h.mapper = restmapper.NewDeferredDiscoveryRESTMapper(cachedDisco)
+
+	h.initConfig()
+	// Register HTTP path -> handler.
+	mgr.GetWebhookServer().Register("/mutate-lineage", &admission.Webhook{Handler: h})
+
+	return nil
+}
+
+// InjectDecoder lets controller-runtime give us a decoder for AdmissionReview requests.
+func (h *LineageControllerWebhook) InjectDecoder(d admission.Decoder) error {
+	h.decoder = d
+	return nil
+}
+
+// Handle is called for each AdmissionReview that matches the webhook config.
+func (h *LineageControllerWebhook) Handle(ctx context.Context, req admission.Request) admission.Response {
+	logger := log.FromContext(ctx).WithValues(
+		"gvk", req.Kind.String(),
+		"namespace", req.Namespace,
+		"name", req.Name,
+		"operation", req.Operation,
+	)
+	warn := make(admission.Warnings, 0)
+
+	obj := &unstructured.Unstructured{}
+	if err := h.decodeUnstructured(req, obj); err != nil {
+		return admission.Errored(400, fmt.Errorf("decode object: %w", err))
+	}
+
+	labels, err := h.computeLabels(ctx, obj)
+	for {
+		if err != nil && errors.Is(err, NoAncestors) {
+			return admission.Allowed("object not managed by app")
+		}
+		if err != nil && errors.Is(err, AncestryAmbiguous) {
+			warn = append(warn, "object ancestry ambiguous, using first ancestor found")
+			break
+		}
+		if err != nil {
+			return admission.Errored(500, fmt.Errorf("error computing lineage labels: %w", err))
+		}
+		if err == nil {
+			break
+		}
+	}
+
+	h.applyLabels(obj, labels)
+
+	mutated, err := json.Marshal(obj)
+	if err != nil {
+		return admission.Errored(500, fmt.Errorf("marshal mutated pod: %w", err))
+	}
+	logger.V(1).Info("mutated pod", "namespace", obj.GetNamespace(), "name", obj.GetName())
+	return admission.PatchResponseFromRaw(req.Object.Raw, mutated).WithWarnings(warn...)
+}
+
+func (h *LineageControllerWebhook) computeLabels(ctx context.Context, o *unstructured.Unstructured) (map[string]string, error) {
+	owners := lineage.WalkOwnershipGraph(ctx, h.dynClient, h.mapper, h, o)
+	if len(owners) == 0 {
+		return nil, NoAncestors
+	}
+	obj, err := owners[0].GetUnstructured(ctx, h.dynClient, h.mapper)
+	if err != nil {
+		return nil, err
+	}
+	gv, err := schema.ParseGroupVersion(obj.GetAPIVersion())
+	if err != nil {
+		// should never happen, we got an APIVersion right from the API
+		return nil, fmt.Errorf("could not parse APIVersion %s to a group and version: %w", obj.GetAPIVersion(), err)
+	}
+	if len(owners) > 1 {
+		err = AncestryAmbiguous
+	}
+	return map[string]string{
+		// truncate apigroup to first 63 chars
+		"apps.cozystack.io/application.group": func(s string) string {
+			if len(s) < 63 {
+				return s
+			}
+			s = s[:63]
+			for b := s[62]; !((b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || (b >= '0' && b <= '9')); s = s[:len(s)-1] {
+				b = s[len(s)-1]
+			}
+			return s
+		}(gv.Group),
+		"apps.cozystack.io/application.kind": obj.GetKind(),
+		"apps.cozystack.io/application.name": obj.GetName(),
+	}, err
+}
+
+func (h *LineageControllerWebhook) applyLabels(o client.Object, labels map[string]string) {
+	existing := o.GetLabels()
+	if existing == nil {
+		existing = make(map[string]string)
+	}
+	for k, v := range labels {
+		existing[k] = v
+	}
+	o.SetLabels(existing)
+}
+
+func (h *LineageControllerWebhook) decodeUnstructured(req admission.Request, out *unstructured.Unstructured) error {
+	if h.decoder != nil {
+		if err := h.decoder.Decode(req, out); err == nil {
+			return nil
+		}
+		if req.Kind.Group != "" || req.Kind.Kind != "" || req.Kind.Version != "" {
+			out.SetGroupVersionKind(schema.GroupVersionKind{
+				Group:   req.Kind.Group,
+				Version: req.Kind.Version,
+				Kind:    req.Kind.Kind,
+			})
+			if err := h.decoder.Decode(req, out); err == nil {
+				return nil
+			}
+		}
+	}
+	if len(req.Object.Raw) == 0 {
+		return errors.New("empty admission object")
+	}
+	return json.Unmarshal(req.Object.Raw, &out.Object)
+}

packages/system/cozystack-controller/templates/certmanager.yaml

@@ -0,0 +1,45 @@
+apiVersion: cert-manager.io/v1
+kind: Issuer
+metadata:
+  name: cozystack-controller-webhook-selfsigned
+  namespace: {{ .Release.Namespace }}
+spec:
+  selfSigned: {}
+---
+apiVersion: cert-manager.io/v1
+kind: Certificate
+metadata:
+  name: cozystack-controller-webhook-ca
+  namespace: {{ .Release.Namespace }}
+spec:
+  secretName: cozystack-controller-webhook-ca
+  duration: 43800h  # 5 years
+  commonName: cozystack-controller-webhook-ca
+  issuerRef:
+    name: cozystack-controller-webhook-selfsigned
+  isCA: true
+---
+apiVersion: cert-manager.io/v1
+kind: Issuer
+metadata:
+  name: cozystack-controller-webhook-ca
+  namespace: {{ .Release.Namespace }}
+spec:
+  ca:
+    secretName: cozystack-controller-webhook-ca
+---
+apiVersion: cert-manager.io/v1
+kind: Certificate
+metadata:
+  name: cozystack-controller-webhook
+  namespace: {{ .Release.Namespace }}
+spec:
+  secretName: cozystack-controller-webhook-cert
+  duration: 8760h
+  renewBefore: 720h
+  issuerRef:
+    name: cozystack-controller-webhook-ca
+  commonName: cozystack-controller
+  dnsNames:
+    - cozystack-controller
+    - cozystack-controller.{{ .Release.Namespace }}.svc

packages/system/cozystack-controller/templates/deployment.yaml

@@ -2,7 +2,6 @@ apiVersion: apps/v1
 kind: Deployment
 metadata:
   name: cozystack-controller
-  namespace: cozy-system
   labels:
     app: cozystack-controller
 spec:
@@ -29,3 +28,15 @@ spec:
         {{- if .Values.cozystackController.disableTelemetry }}
         - --disable-telemetry
         {{- end }}
+        ports:
+        - name: webhook
+          containerPort: 9443
+        volumeMounts:
+          - name: webhook-certs
+            mountPath: /tmp/k8s-webhook-server/serving-certs
+            readOnly: true
+      volumes:
+        - name: webhook-certs
+          secret:
+            secretName: cozystack-controller-webhook-cert
+            defaultMode: 0400

packages/system/cozystack-controller/templates/mutatingwebhookconfiguration.yaml

@@ -0,0 +1,33 @@
+apiVersion: admissionregistration.k8s.io/v1
+kind: MutatingWebhookConfiguration
+metadata:
+  name: lineage
+  annotations:
+    cert-manager.io/inject-ca-from: {{ .Release.Namespace }}/cozystack-controller-webhook
+  labels:
+    app: cozystack-controller
+webhooks:
+  - name: lineage.cozystack.io
+    admissionReviewVersions: ["v1"]
+    sideEffects: None
+    clientConfig:
+      service:
+        name: cozystack-controller
+        namespace: {{ .Release.Namespace }}
+        path: /mutate-lineage
+    rules:
+      - operations: ["CREATE"]
+        apiGroups: [""]
+        apiVersions: ["v1"]
+        resources: ["pods","secrets", "services", "persistentvolumeclaims"]
+    failurePolicy: Fail
+    namespaceSelector:
+      matchExpressions:
+        - key: cozystack.io/system
+          operator: NotIn
+          values:
+            - "true"
+        - key: kubernetes.io/metadata.name
+          operator: NotIn
+          values:
+            - kube-system

packages/system/cozystack-controller/templates/service.yaml

@@ -0,0 +1,15 @@
+apiVersion: v1
+kind: Service
+metadata:
+  name: cozystack-controller
+  labels:
+    app: cozystack-controller
+spec:
+  type: ClusterIP
+  ports:
+    - port: 443
+      targetPort: 9443
+      protocol: TCP
+      name: webhook
+  selector:
+    app: cozystack-controller

pkg/lineage/lineage.go

@@ -0,0 +1,193 @@
+package lineage
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"strings"
+
+	helmv2 "github.com/fluxcd/helm-controller/api/v2"
+	"k8s.io/apimachinery/pkg/api/meta"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/client-go/dynamic"
+	"sigs.k8s.io/controller-runtime/pkg/log"
+)
+
+const (
+	HRAPIVersion = "helm.toolkit.fluxcd.io/v2"
+	HRKind       = "HelmRelease"
+	HRLabel      = "helm.toolkit.fluxcd.io/name"
+)
+
+type ObjectID struct {
+	APIVersion string
+	Kind       string
+	Namespace  string
+	Name       string
+}
+
+func (o ObjectID) GetUnstructured(ctx context.Context, client dynamic.Interface, mapper meta.RESTMapper) (*unstructured.Unstructured, error) {
+	u, err := getUnstructuredObject(ctx, client, mapper, o.APIVersion, o.Kind, o.Namespace, o.Name)
+	if err != nil {
+		return nil, err
+	}
+	return u, nil
+}
+
+func WalkOwnershipGraph(
+	ctx context.Context,
+	client dynamic.Interface,
+	mapper meta.RESTMapper,
+	appMapper AppMapper,
+	obj *unstructured.Unstructured,
+	memory ...interface{},
+) (out []ObjectID) {
+
+	id := ObjectID{APIVersion: obj.GetAPIVersion(), Kind: obj.GetKind(), Namespace: obj.GetNamespace(), Name: obj.GetName()}
+	out = []ObjectID{}
+	l := log.FromContext(ctx)
+
+	l.Info("processing object", "apiVersion", obj.GetAPIVersion(), "kind", obj.GetKind(), "name", obj.GetName())
+	var visited map[ObjectID]bool
+	var ok bool
+	if len(memory) == 1 {
+		visited, ok = memory[0].(map[ObjectID]bool)
+		if !ok {
+			l.Error(
+				fmt.Errorf("invalid argument"), "could not parse visited map in WalkOwnershipGraph call",
+				"received", memory[0], "expected", "map[ObjectID]bool",
+			)
+			return out
+		}
+	}
+
+	if len(memory) == 0 {
+		visited = make(map[ObjectID]bool)
+	}
+
+	if len(memory) != 0 && len(memory) != 1 {
+		l.Error(
+			fmt.Errorf("invalid argument count"), "could not parse variadic arguments to WalkOwnershipGraph",
+			"args passed", len(memory)+5, "expected args", "4|5",
+		)
+		return out
+	}
+
+	if visited[id] {
+		return out
+	}
+
+	visited[id] = true
+
+	ownerRefs := obj.GetOwnerReferences()
+	for _, owner := range ownerRefs {
+		ownerObj, err := getUnstructuredObject(ctx, client, mapper, owner.APIVersion, owner.Kind, obj.GetNamespace(), owner.Name)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "Could not fetch owner %s/%s (%s): %v\n", obj.GetNamespace(), owner.Name, owner.Kind, err)
+			continue
+		}
+
+		out = append(out, WalkOwnershipGraph(ctx, client, mapper, appMapper, ownerObj, visited)...)
+	}
+
+	// if object has owners, it couldn't be owned directly by the custom app
+	if len(ownerRefs) > 0 {
+		return
+	}
+
+	// I want "if err1 != nil go to next block, if err2 != nil, go to next block, etc semantics",
+	// like an early return from a function, but if all checks succeed, I don't want to do the rest
+	// of the function, so it's a `for { if err { break } if othererr { break } if allgood { return }
+	for {
+		if obj.GetAPIVersion() != HRAPIVersion || obj.GetKind() != HRKind {
+			break
+		}
+		hr := helmReleaseFromUnstructured(obj)
+		if hr == nil {
+			break
+		}
+		a, k, p, err := appMapper.Map(hr)
+		if err != nil {
+			break
+		}
+		ownerObj, err := getUnstructuredObject(ctx, client, mapper, a, k, obj.GetNamespace(), strings.TrimPrefix(obj.GetName(), p))
+		if err != nil {
+			break
+		}
+		// successfully mapped a HelmRelease to a custom app, no need to continue
+		out = append(out,
+			ObjectID{
+				APIVersion: ownerObj.GetAPIVersion(),
+				Kind:       ownerObj.GetKind(),
+				Namespace:  ownerObj.GetNamespace(),
+				Name:       ownerObj.GetName(),
+			},
+		)
+		return
+	}
+
+	labels := obj.GetLabels()
+	name, ok := labels[HRLabel]
+	if !ok {
+		return
+	}
+	ownerObj, err := getUnstructuredObject(ctx, client, mapper, HRAPIVersion, HRKind, obj.GetNamespace(), name)
+	if err != nil {
+		return
+	}
+	out = append(out, WalkOwnershipGraph(ctx, client, mapper, appMapper, ownerObj, visited)...)
+
+	return
+}
+
+func getUnstructuredObject(
+	ctx context.Context,
+	client dynamic.Interface,
+	mapper meta.RESTMapper,
+	apiVersion, kind, namespace, name string,
+) (*unstructured.Unstructured, error) {
+	l := log.FromContext(ctx)
+	gv, err := schema.ParseGroupVersion(apiVersion)
+	if err != nil {
+		l.Error(
+			err, "failed to parse groupversion",
+			"apiVersion", apiVersion,
+		)
+		return nil, err
+	}
+	gvk := schema.GroupVersionKind{
+		Group:   gv.Group,
+		Version: gv.Version,
+		Kind:    kind,
+	}
+
+	mapping, err := mapper.RESTMapping(gvk.GroupKind(), gvk.Version)
+	if err != nil {
+		l.Error(err, "Could not map GVK "+gvk.String())
+		return nil, err
+	}
+
+	ns := namespace
+	if mapping.Scope.Name() != meta.RESTScopeNameNamespace {
+		ns = ""
+	}
+
+	ownerObj, err := client.Resource(mapping.Resource).Namespace(ns).Get(ctx, name, metav1.GetOptions{})
+	if err != nil {
+		return nil, err
+	}
+	return ownerObj, nil
+}
+
+func helmReleaseFromUnstructured(obj *unstructured.Unstructured) *helmv2.HelmRelease {
+	if obj.GetAPIVersion() == HRAPIVersion && obj.GetKind() == HRKind {
+		hr := &helmv2.HelmRelease{}
+		if err := runtime.DefaultUnstructuredConverter.FromUnstructured(obj.Object, hr); err == nil {
+			return hr
+		}
+	}
+	return nil
+}

pkg/lineage/lineage_test.go

@@ -0,0 +1,53 @@
+package lineage
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"testing"
+
+	"github.com/go-logr/logr"
+	"github.com/go-logr/zapr"
+	"go.uber.org/zap"
+	"k8s.io/apimachinery/pkg/api/meta"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime/schema"
+	"k8s.io/client-go/discovery"
+	"k8s.io/client-go/discovery/cached/memory"
+	"k8s.io/client-go/dynamic"
+	"k8s.io/client-go/restmapper"
+	"sigs.k8s.io/controller-runtime/pkg/client/config"
+)
+
+var (
+	dynClient dynamic.Interface
+	mapper    meta.RESTMapper
+	l         logr.Logger
+	ctx       context.Context
+)
+
+func init() {
+	cfg := config.GetConfigOrDie()
+
+	dynClient, _ = dynamic.NewForConfig(cfg)
+
+	discoClient, _ := discovery.NewDiscoveryClientForConfig(cfg)
+
+	cachedDisco := memory.NewMemCacheClient(discoClient)
+	mapper = restmapper.NewDeferredDiscoveryRESTMapper(cachedDisco)
+
+	zapLogger, _ := zap.NewDevelopment()
+	l = zapr.NewLogger(zapLogger)
+	ctx = logr.NewContext(context.Background(), l)
+}
+
+func TestWalkingOwnershipGraph(t *testing.T) {
+	obj, err := dynClient.Resource(schema.GroupVersionResource{"", "v1", "pods"}).Namespace(os.Args[1]).Get(ctx, os.Args[2], metav1.GetOptions{})
+	if err != nil {
+		t.Fatal(err)
+	}
+	nodes := WalkOwnershipGraph(ctx, dynClient, mapper, obj)
+	for _, node := range nodes {
+		fmt.Printf("%#v\n", node)
+	}
+}

pkg/lineage/mapper.go

@@ -0,0 +1,49 @@
+package lineage
+
+import (
+	"fmt"
+	"strings"
+
+	helmv2 "github.com/fluxcd/helm-controller/api/v2"
+)
+
+type AppMapper interface {
+	Map(*helmv2.HelmRelease) (apiVersion, kind, prefix string, err error)
+}
+
+type stubMapper struct{}
+
+var stubMapperMap = map[string]string{
+	"cozystack-extra/bootbox":        "apps.cozystack.io/v1alpha1/BootBox/",
+	"cozystack-apps/bucket":          "apps.cozystack.io/v1alpha1/Bucket/bucket-",
+	"cozystack-apps/clickhouse":      "apps.cozystack.io/v1alpha1/ClickHouse/clickhouse-",
+	"cozystack-extra/etcd":           "apps.cozystack.io/v1alpha1/Etcd/",
+	"cozystack-apps/ferretdb":        "apps.cozystack.io/v1alpha1/FerretDB/ferretdb-",
+	"cozystack-apps/http-cache":      "apps.cozystack.io/v1alpha1/HTTPCache/http-cache-",
+	"cozystack-extra/info":           "apps.cozystack.io/v1alpha1/Info/",
+	"cozystack-extra/ingress":        "apps.cozystack.io/v1alpha1/Ingress/",
+	"cozystack-apps/kafka":           "apps.cozystack.io/v1alpha1/Kafka/kafka-",
+	"cozystack-apps/kubernetes":      "apps.cozystack.io/v1alpha1/Kubernetes/kubernetes-",
+	"cozystack-extra/monitoring":     "apps.cozystack.io/v1alpha1/Monitoring/",
+	"cozystack-apps/mysql":           "apps.cozystack.io/v1alpha1/MySQL/mysql-",
+	"cozystack-apps/nats":            "apps.cozystack.io/v1alpha1/NATS/nats-",
+	"cozystack-apps/postgres":        "apps.cozystack.io/v1alpha1/Postgres/postgres-",
+	"cozystack-apps/rabbitmq":        "apps.cozystack.io/v1alpha1/RabbitMQ/rabbitmq-",
+	"cozystack-apps/redis":           "apps.cozystack.io/v1alpha1/Redis/redis-",
+	"cozystack-extra/seaweedfs":      "apps.cozystack.io/v1alpha1/SeaweedFS/",
+	"cozystack-apps/tcp-balancer":    "apps.cozystack.io/v1alpha1/TCPBalancer/tcp-balancer-",
+	"cozystack-apps/tenant":          "apps.cozystack.io/v1alpha1/Tenant/tenant-",
+	"cozystack-apps/virtual-machine": "apps.cozystack.io/v1alpha1/VirtualMachine/virtual-machine-",
+	"cozystack-apps/vm-disk":         "apps.cozystack.io/v1alpha1/VMDisk/vm-disk-",
+	"cozystack-apps/vm-instance":     "apps.cozystack.io/v1alpha1/VMInstance/vm-instance-",
+	"cozystack-apps/vpn":             "apps.cozystack.io/v1alpha1/VPN/vpn-",
+}
+
+func (s *stubMapper) Map(hr *helmv2.HelmRelease) (string, string, string, error) {
+	val, ok := stubMapperMap[hr.Spec.Chart.Spec.SourceRef.Name+"/"+hr.Spec.Chart.Spec.Chart]
+	if !ok {
+		return "", "", "", fmt.Errorf("cannot map helm release %s/%s to dynamic app", hr.Namespace, hr.Name)
+	}
+	split := strings.Split(val, "/")
+	return strings.Join(split[:2], "/"), split[2], split[3], nil
+}