Python3 Migrate

venv/lib/python3.7/site-packages/mopidy/zeroconf.py

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+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