Improve error messages for project Delete errors

Author: Vadim Rutkovsky

pkg/project/apiserver/registry/project/proxy/proxy.go

@@ -8,13 +8,16 @@ import (
 	metainternal "k8s.io/apimachinery/pkg/apis/meta/internalversion"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/util/wait"
 	"k8s.io/apimachinery/pkg/watch"
 	apirequest "k8s.io/apiserver/pkg/endpoints/request"
 	"k8s.io/apiserver/pkg/registry/rest"
 	corev1client "k8s.io/client-go/kubernetes/typed/core/v1"
 	"k8s.io/kubernetes/pkg/printers"
 	printerstorage "k8s.io/kubernetes/pkg/printers/storage"
 
+	"k8s.io/klog/v2"
+
 	"github.com/openshift/api/project"
 	"github.com/openshift/apiserver-library-go/pkg/authorization/scope"
 	"github.com/openshift/openshift-apiserver/pkg/api/apihelpers"
@@ -208,32 +211,50 @@ func (s *REST) Update(ctx context.Context, name string, objInfo rest.UpdatedObje
 
 var _ = rest.GracefulDeleter(&REST{})
 
+// maxRetriesOnConflict is the maximum retry count for Delete calls which
+// result in resource conflicts.
+const maxRetriesOnConflict = 10
+
 // Delete deletes a Project specified by its name
 func (s *REST) Delete(ctx context.Context, name string, objectFunc rest.ValidateObjectFunc, options *metav1.DeleteOptions) (runtime.Object, bool, error) {
+	klog.V(2).Infof("Project delete name=%s: start", name)
 	var opts metav1.DeleteOptions
 	if options != nil {
 		opts = *options
 	}
-	if objectFunc != nil {
-		obj, err := s.Get(ctx, name, &metav1.GetOptions{})
-		if err != nil {
-			return nil, false, err
-		}
-		projectObj, ok := obj.(*projectapi.Project)
-		if !ok || projectObj == nil {
-			return nil, false, fmt.Errorf("not a project: %#v", obj)
-		}
-
-		// Make sure the object hasn't changed between Get and Delete - pass UID and RV to delete options
-		if opts.Preconditions == nil {
-			opts.Preconditions = &metav1.Preconditions{}
-		}
-		opts.Preconditions.UID = &projectObj.UID
-		opts.Preconditions.ResourceVersion = &projectObj.ResourceVersion
-
-		if err := objectFunc(ctx, obj); err != nil {
-			return nil, false, err
+	err := wait.ExponentialBackoff(wait.Backoff{Steps: maxRetriesOnConflict}, func() (bool, error) {
+		if objectFunc != nil {
+			klog.V(2).Infof("Project delete name=%s: validation func=%#v", name, objectFunc)
+			obj, err := s.Get(ctx, name, &metav1.GetOptions{})
+			if err != nil {
+				klog.V(2).Infof("Project delete name=%s: unable to get project: %#v", name, err)
+				return false, fmt.Errorf("unable to get project: %w", err)
+			}
+			projectObj, ok := obj.(*projectapi.Project)
+			if !ok || projectObj == nil {
+				klog.V(2).Infof("Project delete name=%s: not a project: %#v", name, err)
+				return false, fmt.Errorf("not a project: %#v", obj)
+			}
+
+			// Make sure the object hasn't changed between Get and Delete - pass UID and RV to delete options
+			if opts.Preconditions == nil {
+				opts.Preconditions = &metav1.Preconditions{}
+			}
+			opts.Preconditions.UID = &projectObj.UID
+			opts.Preconditions.ResourceVersion = &projectObj.ResourceVersion
+
+			if err := objectFunc(ctx, obj); err != nil {
+				klog.V(2).Infof("Project delete name=%s: validation func failed: %#v", name, err)
+				return false, fmt.Errorf("validation func failed: %w", err)
+			}
+			klog.V(2).Infof("Project delete name=%s: objectFunc validation complete", name)
 		}
+		err := s.client.Delete(ctx, name, opts)
+		klog.V(2).Infof("Project delete name=%s: complete err=%v", name, err)
+		return true, err
+	})
+	if err != nil {
+		return nil, false, err
 	}
-	return &metav1.Status{Status: metav1.StatusSuccess}, false, s.client.Delete(ctx, name, opts)
+	return &metav1.Status{Status: metav1.StatusSuccess}, false, nil
 }