slapos_panel: do not create multiple Instance Node from an Instance Tree

master/bt5/slapos_panel/SkinTemplateItem/portal_skins/slapos_panel/InstanceTree_addSlapOSInstanceNode.py

@@ -2,14 +2,37 @@ from Products.ERP5Type.Message import translateString
 
 portal = context.getPortalObject()
 instance_tree = context
-
 software_instance = instance_tree.getSuccessorValue(portal_type='Software Instance')
 
+# If an Instance Node already exist, do nothing
+instance_node = portal.portal_catalog.getResultValue(
+  portal_type="Instance Node",
+  specialise__uid=software_instance.getUid()
+)
+if (instance_node is not None):
+  return instance_node.Base_redirect(
+    keep_items={
+      'portal_status_message': translateString('Instance Node already created.')
+    }
+  )
+
+# If an Instance Node is not yet indexed, do nothing
+tag = "%s_createInstanceNode" % instance_tree.getUid()
+if (0 < portal.portal_activities.countMessageWithTag(tag)):
+  # The instance node is already under creation but can not be fetched from catalog
+  return instance_tree.Base_redirect(
+    keep_items={
+      'portal_status_message': translateString('New Instance Node under creation.')
+    }
+  )
+
+
 instance_node = portal.compute_node_module.newContent(
   portal_type='Instance Node',
   title=instance_tree.getTitle(),
   specialise_value=software_instance,
-  follow_up_value=software_instance.getFollowUpValue()
+  follow_up_value=software_instance.getFollowUpValue(),
+  activate_kw={'tag': tag}
 )
 instance_node.validate()