[AG-DEV] pyDNSServiceRegister ServiceDiscovery.py issue

[Douglas Kosovic]

Hi,

The problem is with the glib mainloop that Avahi uses isn't compatible with 
the one that the VenueClient uses. The asynchronous ServiceResolve callbacks 
never get called regardless of if bonjour-py or the native Avahi python API 
is used. Publishing works as no asynchronous callbacks are used.

Looks like I'm going to have to use an external program to return a list of 
service URLs within a specified duration, I'll look into to doing that later 
this week.

I wouldn't mind if None is used for the host-name argument of the 
pyDNSServiceRegister() call in ServiceDiscovery.py for other platforms, as 
an address record for that host is created and Avahi stops producing invalid 
DNS record messages.

> In the pyDNSServiceRegister() call in ServiceDiscovery.py, it is using 
> socket.gethostbyname(socket.gethostname()) which returns an IP address, 
> for the hostname argument. Unfortunately later version of Avahi (the 
> Bonjour compatible package that comes with later linux distributions) 
> doesn't accept IP addresses as valid arguments for the hostname field, it 
> needs to be a hostname resolvable by either DNS or mDNS.
>
> Just wondering if it okay to avoid the issue, by replacing 
> gethostbyname(socket.gethostname()) with None (i.e. NULL, as per Apple's 
> recommendation to use the computer's default host name)? It then works 
> fine with Avahi.
>
> I'm also looking into why __ResolveCallback doesn't get called with Avahi, 
> but __BrowseCallback has no problems, it's odd as the 
> pyDNSServiceResolve() call completes successfully. I may end up just 
> statically linking bonjour-py against Apple's mDNSresponder library if I 
> don't find a solution for the callback

I can't use a static libraries mDNSresponder library as it isn't compatible 
with the IPC for the locally running Avahi daemon.


Cheers,
Doug