151 lines
4.3 KiB
Python
151 lines
4.3 KiB
Python
import logging
|
|
import string
|
|
|
|
logger = logging.getLogger(__name__)
|
|
|
|
try:
|
|
import dbus
|
|
except ImportError:
|
|
dbus = None
|
|
|
|
_AVAHI_IF_UNSPEC = -1
|
|
_AVAHI_PROTO_UNSPEC = -1
|
|
_AVAHI_PUBLISHFLAGS_NONE = 0
|
|
|
|
|
|
def _is_loopback_address(host):
|
|
return (
|
|
host.startswith("127.")
|
|
or host.startswith("::ffff:127.")
|
|
or host == "::1"
|
|
)
|
|
|
|
|
|
def _convert_text_list_to_dbus_format(text_list):
|
|
array = dbus.Array(signature="ay")
|
|
for text in text_list:
|
|
array.append([dbus.Byte(ord(c)) for c in text])
|
|
return array
|
|
|
|
|
|
class Zeroconf:
|
|
|
|
"""Publish a network service with Zeroconf.
|
|
|
|
Currently, this only works on Linux using Avahi via D-Bus.
|
|
|
|
:param str name: human readable name of the service, e.g. 'MPD on neptune'
|
|
:param str stype: service type, e.g. '_mpd._tcp'
|
|
:param int port: TCP port of the service, e.g. 6600
|
|
:param str domain: local network domain name, defaults to ''
|
|
:param str host: interface to advertise the service on, defaults to ''
|
|
:param text: extra information depending on ``stype``, defaults to empty
|
|
list
|
|
:type text: list of str
|
|
"""
|
|
|
|
def __init__(self, name, stype, port, domain="", host="", text=None):
|
|
self.stype = stype
|
|
self.port = port
|
|
self.domain = domain
|
|
self.host = host
|
|
self.text = text or []
|
|
|
|
self.bus = None
|
|
self.server = None
|
|
self.group = None
|
|
self.display_hostname = None
|
|
self.name = None
|
|
|
|
if dbus:
|
|
try:
|
|
self.bus = dbus.SystemBus()
|
|
self.server = dbus.Interface(
|
|
self.bus.get_object("org.freedesktop.Avahi", "/"),
|
|
"org.freedesktop.Avahi.Server",
|
|
)
|
|
self.display_hostname = f"{self.server.GetHostName()}"
|
|
self.name = string.Template(name).safe_substitute(
|
|
hostname=self.display_hostname, port=port
|
|
)
|
|
except dbus.exceptions.DBusException as e:
|
|
logger.debug("%s: Server failed: %s", self, e)
|
|
|
|
def __str__(self):
|
|
return (
|
|
f"Zeroconf service {self.name!r} "
|
|
f"({self.stype} at [{self.host}]:{self.port:d})"
|
|
)
|
|
|
|
def publish(self):
|
|
"""Publish the service.
|
|
|
|
Call when your service starts.
|
|
"""
|
|
|
|
if _is_loopback_address(self.host):
|
|
logger.debug(
|
|
"%s: Publish on loopback interface is not supported.", self
|
|
)
|
|
return False
|
|
|
|
if not dbus:
|
|
logger.debug("%s: dbus not installed; publish failed.", self)
|
|
return False
|
|
|
|
if not self.bus:
|
|
logger.debug("%s: Bus not available; publish failed.", self)
|
|
return False
|
|
|
|
if not self.server:
|
|
logger.debug("%s: Server not available; publish failed.", self)
|
|
return False
|
|
|
|
try:
|
|
if not self.bus.name_has_owner("org.freedesktop.Avahi"):
|
|
logger.debug(
|
|
"%s: Avahi service not running; publish failed.", self
|
|
)
|
|
return False
|
|
|
|
self.group = dbus.Interface(
|
|
self.bus.get_object(
|
|
"org.freedesktop.Avahi", self.server.EntryGroupNew()
|
|
),
|
|
"org.freedesktop.Avahi.EntryGroup",
|
|
)
|
|
|
|
self.group.AddService(
|
|
_AVAHI_IF_UNSPEC,
|
|
_AVAHI_PROTO_UNSPEC,
|
|
dbus.UInt32(_AVAHI_PUBLISHFLAGS_NONE),
|
|
self.name,
|
|
self.stype,
|
|
self.domain,
|
|
self.host,
|
|
dbus.UInt16(self.port),
|
|
_convert_text_list_to_dbus_format(self.text),
|
|
)
|
|
|
|
self.group.Commit()
|
|
logger.debug("%s: Published", self)
|
|
return True
|
|
except dbus.exceptions.DBusException as e:
|
|
logger.debug("%s: Publish failed: %s", self, e)
|
|
return False
|
|
|
|
def unpublish(self):
|
|
"""Unpublish the service.
|
|
|
|
Call when your service shuts down.
|
|
"""
|
|
|
|
if self.group:
|
|
try:
|
|
self.group.Reset()
|
|
logger.debug("%s: Unpublished", self)
|
|
except dbus.exceptions.DBusException as e:
|
|
logger.debug("%s: Unpublish failed: %s", self, e)
|
|
finally:
|
|
self.group = None
|