fix(uninstall): rely on OLM to delete operator resources via CSV deletion (#27)

When multiple install plans are present for single operator,
select the resources of install plan containing the installed CSV
while uninstalling the operator.

Author: varshaprasad96

internal/pkg/action/operator_uninstall.go

@@ -7,7 +7,6 @@ import (
 
 	v1 "github.com/operator-framework/api/pkg/operators/v1"
 	"github.com/operator-framework/api/pkg/operators/v1alpha1"
-	"github.com/operator-framework/operator-registry/pkg/lib/bundle"
 	"github.com/spf13/pflag"
 	apierrors "k8s.io/apimachinery/pkg/api/errors"
 	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
@@ -66,22 +65,13 @@ func (u *OperatorUninstall) Run(ctx context.Context) error {
 		return fmt.Errorf("operator package %q not found", u.Package)
 	}
 
-	// Since the install plan is owned by the subscription, we need to
-	// read all of the resource references from the install plan before
-	// deleting the subscription.
-	var crds, csvs, others []controllerutil.Object
-	if sub.Status.InstallPlanRef != nil {
-		ipKey := types.NamespacedName{
-			Namespace: sub.Status.InstallPlanRef.Namespace,
-			Name:      sub.Status.InstallPlanRef.Name,
-		}
-		var err error
-		crds, csvs, others, err = u.getInstallPlanResources(ctx, ipKey)
-		if err != nil {
-			return fmt.Errorf("get install plan resources: %v", err)
-		}
+	csv, err := u.getInstalledCSV(ctx, sub)
+	if err != nil {
+		return fmt.Errorf("get installed CSV %q: %v", sub.Status.InstalledCSV, err)
 	}
 
+	crds := getCRDs(csv)
+
 	// Delete the subscription first, so that no further installs or upgrades
 	// of the operator occur while we're cleaning up.
 	if err := u.deleteObjects(ctx, sub); err != nil {
@@ -96,9 +86,10 @@ func (u *OperatorUninstall) Run(ctx context.Context) error {
 		}
 	}
 
-	// Delete CSVs and all other objects created by the install plan.
-	objects := append(csvs, others...)
-	if err := u.deleteObjects(ctx, objects...); err != nil {
+	// OLM puts an ownerref on every namespaced resource to the CSV,
+	// and an owner label on every cluster scoped resource. When CSV is deleted
+	// kube and olm gc will remove all the referenced resources.
+	if err := u.deleteObjects(ctx, csv); err != nil {
 		return err
 	}
 
@@ -140,43 +131,41 @@ func (u *OperatorUninstall) deleteObjects(ctx context.Context, objs ...controlle
 	return waitForDeletion(ctx, u.config.Client, objs...)
 }
 
-func (u *OperatorUninstall) getInstallPlanResources(ctx context.Context, installPlanKey types.NamespacedName) (crds, csvs, others []controllerutil.Object, err error) {
-	installPlan := &v1alpha1.InstallPlan{}
-	if err := u.config.Client.Get(ctx, installPlanKey, installPlan); err != nil {
-		return nil, nil, nil, fmt.Errorf("get install plan: %v", err)
+func (u *OperatorUninstall) getInstalledCSV(ctx context.Context, subscription *v1alpha1.Subscription) (*v1alpha1.ClusterServiceVersion, error) {
+	key := types.NamespacedName{
+		Name:      subscription.Status.InstalledCSV,
+		Namespace: subscription.GetNamespace(),
 	}
 
-	for _, step := range installPlan.Status.Plan {
-		obj := &unstructured.Unstructured{}
+	installedCSV := &v1alpha1.ClusterServiceVersion{}
+	if err := u.config.Client.Get(ctx, key, installedCSV); err != nil {
+		return nil, err
+	}
 
-		obj.SetGroupVersionKind(schema.GroupVersionKind{
-			Group:   step.Resource.Group,
-			Version: step.Resource.Version,
-			Kind:    step.Resource.Kind,
-		})
-		obj.SetName(step.Resource.Name)
+	installedCSV.SetGroupVersionKind(schema.GroupVersionKind{
+		Kind:    csvKind,
+		Version: installedCSV.GroupVersionKind().Version,
+		Group:   installedCSV.GroupVersionKind().Group,
+	})
+	return installedCSV, nil
+}
 
-		// TODO: Use RESTMapper interface to identify if the object is namespaced or not.
-		// Reference: https://github.com/kubernetes-sigs/controller-runtime/blob/master/pkg/client/namespaced_client.go
-		if supported, namespaced := bundle.IsSupported(step.Resource.Kind); supported && bool(namespaced) {
-			obj.SetNamespace(installPlanKey.Namespace)
-		}
+func getCRDs(csv *v1alpha1.ClusterServiceVersion) (crds []controllerutil.Object) {
+	for _, resource := range csv.Status.RequirementStatus {
+		if resource.Kind == crdKind {
+			obj := &unstructured.Unstructured{}
+			obj.SetGroupVersionKind(schema.GroupVersionKind{
+				Group:   resource.Group,
+				Version: resource.Version,
+				Kind:    resource.Kind,
+			})
+			obj.SetName(resource.Name)
+			obj.SetNamespace(csv.GetNamespace())
 
-		switch step.Resource.Kind {
-		case crdKind:
 			crds = append(crds, obj)
-		case csvKind:
-			csvs = append(csvs, obj)
-		default:
-			// Skip non-CRD/non-CSV resources in the install plan that were not created by the install plan.
-			// This means we avoid deleting things like the default service account.
-			if step.Status != v1alpha1.StepStatusCreated {
-				continue
-			}
-			others = append(others, obj)
 		}
 	}
-	return crds, csvs, others, nil
+	return
 }
 
 func contains(haystack []string, needle string) bool {