Discover fails if there is a misbehaved device in the network #201
Description
The discover function in code.py does not check the response received to the SSDP search query, as explicited in this comment:
# Only Zone Players will respond, given the value of ST in the
# PLAYER_SEARCH message. It doesn't matter what response they make. All
# we care about is the IP address
If a device on the network is misbehaved and responds faster than the Zone Players, the discovery function fails. Unfortunately, this is not just a theoretical issue: for some reason, the leapcast software (https://github.com/dz0ny/leapcast) does respond to SoCo's search query. I know leapcast is probably at fault here, but a little sanity check in SoCo wouldn't hurt.
A quick fix is to check if the response contains the "Sonos" string, it is quite crude and could probably be refined, but it works. Like this:
while True:
response, _, _ = select.select([_sock], [], [], timeout)
# Only Zone Players will respond, given the value of ST in the
# PLAYER_SEARCH message. It doesn't matter what response they make. All
# we care about is the IP address
if response:
data, addr = _sock.recvfrom(1024)
if not "Sonos" in data:
continue
# Now we have an IP, we can build a SoCo instance and query that player
# for the topology to find the other players. It is much more efficient
# to rely upon the Zone Player's ability to find the others, than to
# wait for query responses from them ourselves.
zone = config.SOCO_CLASS(addr[0])
if include_invisible:
return zone.all_zones
else:
return zone.visible_zones
else:
return None