fix: delete folders using postorder (#113493)

* fix: delete folders using postorder

* chore: use helper function and do not add method to Folder store

- addresses other review comments fixing log messages and cleans up the unit tests

* chore: run library element tests on modes 2,3,5 only

* chore: adjust to folder.SortByPostorder(folders []*Folder)

* chore: run library panels tests in mode 2,3,5 only

* chore: run tests in all modes and increase timeout

- adjusting the modes and tweaking configs will be done separately

pkg/services/folder/folderimpl/folder.go

@@ -1241,15 +1241,16 @@ func (s *Service) nestedFolderDelete(ctx context.Context, cmd *folder.DeleteFold
 		s.log.ErrorContext(ctx, "failed to get descendant folders", "error", err)
 		return descendantUIDs, err
 	}
+	descendants = folder.SortByPostorder(descendants)
 
 	for _, f := range descendants {
 		descendantUIDs = append(descendantUIDs, f.UID)
 	}
-	s.log.InfoContext(ctx, "deleting folder descendants", "org_id", cmd.OrgID, "uid", cmd.UID)
+	s.log.InfoContext(ctx, "deleting legacy folder descendants", "org_id", cmd.OrgID, "uid", cmd.UID, "descendantsUIDs", strings.Join(descendantUIDs, ","))
 
 	err = s.store.Delete(ctx, descendantUIDs, cmd.OrgID)
 	if err != nil {
-		s.log.InfoContext(ctx, "failed deleting descendants", "org_id", cmd.OrgID, "parent_uid", cmd.UID, "err", err)
+		s.log.ErrorContext(ctx, "failed to delete legacy folder descendants", "org_id", cmd.OrgID, "parent_uid", cmd.UID, "descendantsUIDs", strings.Join(descendantUIDs, ","), "err", err)
 		return descendantUIDs, err
 	}
 	return descendantUIDs, nil

pkg/services/folder/folderimpl/folder_unifiedstorage.go

@@ -618,12 +618,14 @@ func (s *Service) deleteFromApiServer(ctx context.Context, cmd *folder.DeleteFol
 	if err != nil {
 		return err
 	}
+	descFolders = folder.SortByPostorder(descFolders)
 
 	folders := []string{}
 	for _, f := range descFolders {
 		folders = append(folders, f.UID)
 	}
 	// must delete children first, then the parent folder
+	s.log.InfoContext(ctx, "deleting folder with descendants", "org_id", cmd.OrgID, "uid", cmd.UID, "folderUIDs", strings.Join(folders, ","))
 	folders = append(folders, cmd.UID)
 
 	if cmd.ForceDeleteRules {

pkg/services/folder/folderimpl/folder_unifiedstorage_test.go

@@ -880,6 +880,7 @@ func TestIntegrationDeleteFoldersFromApiServer(t *testing.T) {
 		registry:               make(map[string]folder.RegistryService),
 		features:               featuremgmt.WithFeatures(),
 		tracer:                 tracer,
+		log:                    slog.New(logtest.NewNopHandler(t)),
 	}
 	user := &user.SignedInUser{OrgID: 1}
 	ctx := identity.WithRequester(context.Background(), user)