slapos_pdm: do not upgrade if there is no instance yet

master/bt5/slapos_pdm/SkinTemplateItem/portal_skins/slapos_pdm/InstanceTree_createUpgradeDecision.py

@@ -28,6 +28,7 @@ if software_product is None:
 assert software_release.getUrlString() == instance_tree.getUrlString()
 
 compute_node = None
+root_instance = None
 root_instance_list = [
   q for q in instance_tree.getSuccessorValueList(portal_type=["Software Instance", "Slave Instance"])
   if q.getSlapState() != 'destroy_requested']
@@ -65,7 +66,8 @@ allocation_cell_list = software_product.getFollowUpValue().Project_getSoftwarePr
   predicate_portal_type='Allocation Supply Cell'
 )
 
-if compute_node is None:
+if (compute_node is None) and (root_instance is not None):
+  # Do not upgrade if there is no instance yet
   allocation_cell_node_list = [(x, [y.getPortalType() for y in x.getParentValue().getParentValue().getAggregateValueList()]) for x in allocation_cell_list]
   if (root_instance.getPortalType() == 'Slave Instance'):
     allocation_cell_list = [x for x, y in allocation_cell_node_list if ("Remote Node" in y) or ("Instance Node" in y)]