Merge pull request #87 from barney-s/adopt

Add 'addOwnerRef' flag to the spec.

README.md

@@ -70,6 +70,13 @@ aggregation and display of all the components in the Application.
         used as the selector for an Application named "my-cool-app", and each component should contain a label that
         matches.</td>
     </tr>
+    <tr>
+        <td>spec.addOwnerRef</td>
+        <td>bool</td>
+        <td>Flag controlling if the matched resources need to be adopted by the Application object. When adopting, an <a href=https://kubernetes.io/docs/concepts/workloads/controllers/garbage-collection/#owners-and-dependents>OwnerRef</a> to the Application object is inserted into the matched objects <i>.metadata.[]OwnerRefs</i>.
+	The injected OwnerRef has <i>blockOwnerDeletion</i> set to True and <i>controller</i> set to False.
+        </td>
+    </tr>
     <tr>
         <td>spec.descriptor.version</td>
         <td>string</a></td>

pkg/apis/app/v1beta1/application.go

@@ -29,7 +29,12 @@ import (
 
 // Mutate - mutate expected
 func (a *Application) Mutate(rsrc interface{}, labels map[string]string, status interface{}, expected, dependent, observed *resource.ObjectBag) (*resource.ObjectBag, error) {
-	return observed, nil
+	exp := resource.ObjectBag{}
+	for _, o := range observed.Items() {
+		o.Lifecycle = resource.LifecycleManaged
+		exp.Add(o)
+	}
+	return &exp, nil
 }
 
 // Finalize - execute finalizers
@@ -140,14 +145,20 @@ func (a *Application) Components() []component.Component {
 }
 
 // OwnerRef returns owner ref object with the component's resource as owner
-func (a *Application) OwnerRef() []metav1.OwnerReference {
-	return []metav1.OwnerReference{
-		*metav1.NewControllerRef(a, schema.GroupVersionKind{
-			Group:   SchemeGroupVersion.Group,
-			Version: SchemeGroupVersion.Version,
-			Kind:    "Application",
-		}),
+func (a *Application) OwnerRef() *metav1.OwnerReference {
+	if !a.Spec.AddOwnerRef {
+		return nil
+	}
+
+	isController := false
+	gvk := schema.GroupVersionKind{
+		Group:   SchemeGroupVersion.Group,
+		Version: SchemeGroupVersion.Version,
+		Kind:    "Application",
 	}
+	ref := metav1.NewControllerRef(a, gvk)
+	ref.Controller = &isController
+	return ref
 }
 
 // NewRsrc - return a new resource object

pkg/apis/app/v1beta1/application_types.go

@@ -84,6 +84,10 @@ type ApplicationSpec struct {
 	// More info: https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/#label-selectors
 	Selector *metav1.LabelSelector `json:"selector,omitempty"`
 
+	// AddOwnerRef objects - flag to indicate if we need to add OwnerRefs to matching objects
+	// Matching is done by using Selector to query all ComponentGroupKinds
+	AddOwnerRef bool `json:"addOwnerRef,omitempty"`
+
 	// Info contains human readable key,value pairs for the Application.
 	Info []InfoItem `json:"info,omitempty"`
 

pkg/component/component_test.go

@@ -66,10 +66,9 @@ var FilerObject = Filer{
 
 var _ = Describe("Resource", func() {
 	var c = component.Component{
-		Handle:   nil,
-		Name:     "base",
-		CR:       &FilerObject,
-		OwnerRef: nil,
+		Handle: nil,
+		Name:   "base",
+		CR:     &FilerObject,
 	}
 
 	BeforeEach(func() {

pkg/component/types.go

@@ -28,7 +28,7 @@ type Component struct {
 	Handle
 	Name     string
 	CR       metav1.Object
-	OwnerRef []metav1.OwnerReference
+	OwnerRef *metav1.OwnerReference
 }
 
 // KVMap is a map[string]string

pkg/genericreconciler/genericreconciler.go

@@ -23,6 +23,7 @@ import (
 	"k8s.io/apimachinery/pkg/api/meta"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/runtime/schema"
 	"k8s.io/apimachinery/pkg/types"
 	utilerrors "k8s.io/apimachinery/pkg/util/errors"
 	urt "k8s.io/apimachinery/pkg/util/runtime"
@@ -96,6 +97,7 @@ func specDiffers(o1, o2 metav1.Object) bool {
 		e = reflect.Indirect(reflect.ValueOf(o1)).FieldByName("Data")
 		o = reflect.Indirect(reflect.ValueOf(o2)).FieldByName("Data")
 	}
+
 	if e.IsValid() && o.IsValid() {
 		if reflect.DeepEqual(e.Interface(), o.Interface()) {
 			return false
@@ -104,6 +106,36 @@ func specDiffers(o1, o2 metav1.Object) bool {
 	return true
 }
 
+// If both ownerRefs have the same group/kind/name but different uid, that means at least one of them doesn't exist anymore.
+// If we compare `uid` in this function, we'd set both as owners which is not what we want
+// Because in the case that the original owner is already gone, we want its dependent to be garbage collected with it.
+func isReferringSameObject(a, b metav1.OwnerReference) bool {
+	aGV, err := schema.ParseGroupVersion(a.APIVersion)
+	if err != nil {
+		return false
+	}
+	bGV, err := schema.ParseGroupVersion(b.APIVersion)
+	if err != nil {
+		return false
+	}
+	return aGV == bGV && a.Kind == b.Kind && a.Name == b.Name
+}
+
+func injectOwnerRefs(o metav1.Object, ref *metav1.OwnerReference) bool {
+	if ref == nil {
+		return false
+	}
+	objRefs := o.GetOwnerReferences()
+	for _, r := range objRefs {
+		if isReferringSameObject(*ref, r) {
+			return false
+		}
+	}
+	objRefs = append(objRefs, *ref)
+	o.SetOwnerReferences(objRefs)
+	return true
+}
+
 // ReconcileCR is a generic function that reconciles expected and observed resources
 func (gr *Reconciler) ReconcileCR(namespacedname types.NamespacedName, handle cr.Handle) error {
 	var status interface{}
@@ -239,7 +271,6 @@ func (gr *Reconciler) ReconcileComponent(crname string, c component.Component, s
 		aggregated.Add(expected.Items()...)
 		log.Printf("%s  Expected Resources:\n", cname)
 		for _, e := range expected.Items() {
-			e.Obj.SetOwnerReferences(c.OwnerRef)
 			log.Printf("%s   exp: %s/%s/%s\n", cname, e.Obj.GetNamespace(), reflect.TypeOf(e.Obj).String(), e.Obj.GetName())
 		}
 		log.Printf("%s  Observed Resources:\n", cname)
@@ -262,7 +293,8 @@ func (gr *Reconciler) ReconcileComponent(crname string, c component.Component, s
 			}
 			// rsrc is seen in both expected and observed, update it if needed
 			e.Obj.SetResourceVersion(o.Obj.GetResourceVersion())
-			if e.Lifecycle == resource.LifecycleManaged && specDiffers(e.Obj, o.Obj) && c.Differs(e.Obj, o.Obj) {
+			e.Obj.SetOwnerReferences(o.Obj.GetOwnerReferences())
+			if e.Lifecycle == resource.LifecycleManaged && (specDiffers(e.Obj, o.Obj) && c.Differs(e.Obj, o.Obj) || injectOwnerRefs(e.Obj, c.OwnerRef)) {
 				if err := gr.Update(context.TODO(), e.Obj.(runtime.Object).DeepCopyObject()); err != nil {
 					errs = handleErrorArr("update", eRsrcInfo, err, errs)
 				} else {
@@ -278,6 +310,7 @@ func (gr *Reconciler) ReconcileComponent(crname string, c component.Component, s
 		// rsrc is in expected but not in observed - create
 		if !seen {
 			if e.Lifecycle == resource.LifecycleManaged {
+				injectOwnerRefs(e.Obj, c.OwnerRef)
 				if err := gr.Create(context.TODO(), e.Obj.(runtime.Object)); err != nil {
 					errs = handleErrorArr("Create", cname, err, errs)
 				} else {