On Nov 6, 2013, at 11:47 AM, AMER <amer7...@hotmail.com> wrote:
> Hello,
>
> Thank you, it is OK
> what I did:
> from pox.openflow.of_json import *
> core.openflow.addListeners(self)
> core.openflow.addListenerByName("FlowStatsReceived",
> self._handle_flowstats_received)
> def _handle_flowstats_received (self, event)
So if you renamed the method to _handle_FlowStatsReceived, you wouldn't need
the specific addListenerByName (the addListeners() call would take care of it).
> Best regards,
>
>
> Eng Amer Alghadhban
> COE
> SANS-GCFW
> CEH, SCNP, CCNA
>
>
> Subject: Re: [pox-dev] Listeners in class
> From: murphy.mccau...@gmail.com
> Date: Wed, 6 Nov 2013 10:48:22 -0800
> CC: amer7...@hotmail.com; pox-dev@lists.noxrepo.org
> To: sul...@gmail.com
>
> On Nov 6, 2013, at 9:39 AM, Sulabh Bista <sul...@gmail.com> wrote:
>
> I don't think there are flow and port status events. I guess these are not
> 'events' at all and you should fetch them when you require them.
>
> There are, in fact (mentioned in the Statistics Events section of the
> manual). Though you may need to send requests to get them to fire. :)
>
> On Wed, Nov 6, 2013 at 12:30 PM, Sulabh Bista <sul...@gmail.com> wrote:
> Use the event name with proper case as:
> self.addListenersByname("FlowStatsReceived", self._handle_flowstate_received)
>
> This is good advice. Also use the correct name, as done here (the original
> had "flow*state*received" which I think would have raised an exception...).
> Adding by name is sometimes convenient, but it's fairly "unstructured". A
> safer bet is to actually use the event class itself
> (addListener(of.FlowStatsReceived, ...)).
>
> But there's a bigger problem here. Events are raised by specific objects.
> Does "self" raise the FlowStatsReceived event? Considering it wants to
> *handle* that event, probably not. (Continued below.)
>
> On Wed, Nov 6, 2013 at 9:01 AM, Amer <amer7...@hotmail.com>wrote:
> Hello,
>
> I would like to add listeners to flow and port status inl3.learning.py.
> There is a command
> Self.listento(core)
>
> Sidenote: .listenTo() isn't used much anymore (the version of l3_learning in
> dart doesn't, for example). Use .addListenersByName().
>
> But it is not calling flow or port status function
>
> It wouldn't. You're telling it to listen to events on the core object. Take
> a look at the events raised by the core object:
> https://github.com/noxrepo/pox/blob/carp/pox/core.py#L177
>
> None of them have anything to do with OpenFlow.
>
> I tried with self.addListenersByname("flowstatereceived",
> self._handle_flowstate_received)
> and without self
>
> But it is not work
>
> Coming back to this, your event source here is "self", but this object
> probably doesn't raise the flow stats event (neither does the core object as
> mentioned just above). POX raises OpenFlow events on the OpenFlow nexus
> (core.openflow) and on individual Connection objects, so you need to listen
> to those objects. See:
> https://github.com/noxrepo/pox/blob/carp/pox/openflow/__init__.py#L306
> https://github.com/noxrepo/pox/blob/carp/pox/openflow/of_01.py#L571
>
> You might want to skim through the "The Event System" and "OpenFlow Events"
> section of the manual.
>
>
> TLDR:
> Examples...
>
> If you want to listen to all OpenFlow events, name your methods correctly and
> then use:
> core.openflow.addListeners(self)
>
> If you want to listen to a specific event on a specific connection with a
> specific method, try:
> some_connection.addListenerByName("FlowStatsReceived",
> self._handle_flowstate_received)
>
> Examples in code (there are many, but here are three at random):
> https://github.com/noxrepo/pox/blob/carp/pox/forwarding/l2_learning.py#L182
> https://github.com/noxrepo/pox/blob/carp/pox/forwarding/l2_learning.py#L86
> https://github.com/noxrepo/pox/blob/carp/pox/forwarding/l2_pairs.py#L85
>
>
> Hope that's helpful.
>
> -- Murphy
