Creating a subnet with DHCP enabled either creates or updates a port with device_owner network:dhcp matching the network id to which the subnet belongs. While there is a notification received for the subnet creation, the port creation or update is implicit and has not necessarily taken place when the subnet creation event is received (and similarly we don't get a notification that the port has changed or been deleted when the subnet has DHCP disabled).
My specific use case is that we're trying to index resource create/update/delete events for searchlight and we cannot track the network DHCP ports in the same way as we can ports created explicitly or as part of nova instance boots.
The same problem exists for router interface:attach events, though with a difference that we do at least get a notification indicating the port id created. It would be nice if the ports created when attaching a router to a network also sent port.create notifications.
Tested under mitaka RC-1 (or very close to) with 'messaging' as the notification driver.
Can you tell us a little bit the messages you consume? As far I can tell the 'public' notifications are emitted for Create/
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