gajim-plural/gajim/common/zeroconf/zeroconf_avahi.py

483 lines
18 KiB
Python

## common/zeroconf/zeroconf.py
##
## Copyright (C) 2006 Stefan Bethge <stefan@lanpartei.de>
##
## This file is part of Gajim.
##
## Gajim is free software; you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published
## by the Free Software Foundation; version 3 only.
##
## Gajim is distributed in the hope that it will be useful,
## but WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
## GNU General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with Gajim. If not, see <http://www.gnu.org/licenses/>.
##
import logging
log = logging.getLogger('gajim.c.z.zeroconf_avahi')
try:
import dbus.exceptions
except ImportError:
pass
from gajim.common.zeroconf.zeroconf import Constant, ConstantRI
class Zeroconf:
def __init__(self, new_serviceCB, remove_serviceCB, name_conflictCB,
disconnected_CB, error_CB, name, host, port):
self.avahi = None
self.domain = None # specific domain to browse
self.stype = '_presence._tcp'
self.port = port # listening port that gets announced
self.username = name
self.host = host
self.txt = {} # service data
#XXX these CBs should be set to None when we destroy the object
# (go offline), because they create a circular reference
self.new_serviceCB = new_serviceCB
self.remove_serviceCB = remove_serviceCB
self.name_conflictCB = name_conflictCB
self.disconnected_CB = disconnected_CB
self.error_CB = error_CB
self.service_browser = None
self.domain_browser = None
self.bus = None
self.server = None
self.contacts = {} # all current local contacts with data
self.entrygroup = None
self.connected = False
self.announced = False
self.invalid_self_contact = {}
## handlers for dbus callbacks
def entrygroup_commit_error_CB(self, err):
# left blank for possible later usage
pass
def error_callback1(self, err):
log.debug('Error while resolving: ' + str(err))
def error_callback(self, err):
log.debug(str(err))
# timeouts are non-critical
if str(err) != 'Timeout reached':
self.disconnect()
self.disconnected_CB()
def new_service_callback(self, interface, protocol, name, stype, domain,
flags):
log.debug('Found service %s in domain %s on %i.%i.' % (name, domain,
interface, protocol))
if not self.connected:
return
# synchronous resolving
self.server.ResolveService( int(interface), int(protocol), name, stype,
domain, self.avahi.PROTO_UNSPEC, dbus.UInt32(0),
reply_handler=self.service_resolved_callback,
error_handler=self.error_callback1)
def remove_service_callback(self, interface, protocol, name, stype, domain,
flags):
log.debug('Service %s in domain %s on %i.%i disappeared.' % (name,
domain, interface, protocol))
if not self.connected:
return
if name != self.name:
for key in self.contacts.keys():
val = self.contacts[key]
if val[Constant.BARE_NAME] == name:
# try to reduce instead of delete first
resolved_info = val[Constant.RESOLVED_INFO]
if len(resolved_info) > 1:
for i in range(len(resolved_info)):
if resolved_info[i][ConstantRI.INTERFACE] == interface and resolved_info[i][ConstantRI.PROTOCOL] == protocol:
del self.contacts[key][Constant.RESOLVED_INFO][i]
# if still something left, don't remove
if len(self.contacts[key][Constant.RESOLVED_INFO]) > 1: return
del self.contacts[key]
self.remove_serviceCB(key)
return
def new_service_type(self, interface, protocol, stype, domain, flags):
# Are we already browsing this domain for this type?
if self.service_browser:
return
object_path = self.server.ServiceBrowserNew(interface, protocol, \
stype, domain, dbus.UInt32(0))
self.service_browser = dbus.Interface(self.bus.get_object(
self.avahi.DBUS_NAME, object_path),
self.avahi.DBUS_INTERFACE_SERVICE_BROWSER)
self.service_browser.connect_to_signal('ItemNew',
self.new_service_callback)
self.service_browser.connect_to_signal('ItemRemove',
self.remove_service_callback)
self.service_browser.connect_to_signal('Failure', self.error_callback)
def new_domain_callback(self, interface, protocol, domain, flags):
if domain != 'local':
self.browse_domain(interface, protocol, domain)
def txt_array_to_dict(self, txt_array):
txt_dict = {}
for els in txt_array:
key, val = '', None
for c in els:
c = chr(c)
if val is None:
if c == '=':
val = ''
else:
key += c
else:
val += c
if val is None: # missing '='
val = ''
txt_dict[key] = val
return txt_dict
def service_resolved_callback(self, interface, protocol, name, stype, domain,
host, aprotocol, address, port, txt, flags):
log.debug('Service data for service %s in domain %s on %i.%i:'
% (name, domain, interface, protocol))
log.debug('Host %s (%s), port %i, TXT data: %s' % (host, address,
port, self.txt_array_to_dict(txt)))
if not self.connected:
return
bare_name = name
if name.find('@') == -1:
name = name + '@' + name
# we don't want to see ourselves in the list
if name != self.name:
resolved_info = [(interface, protocol, host, aprotocol, address, port)]
if name in self.contacts:
# Decide whether to try to merge with existing resolved info:
old_name, old_domain, old_resolved_info, old_bare_name, old_txt = self.contacts[name]
if name == old_name and domain == old_domain and bare_name == old_bare_name:
# Seems similar enough, try to merge resolved info:
for i in range(len(old_resolved_info)):
# for now, keep a single record for each (interface, protocol) pair
#
# Note that, theoretically, we could both get IPv4 and
# IPv6 aprotocol responses via the same protocol,
# so this probably needs to be revised again.
if old_resolved_info[i][0:2] == (interface, protocol):
log.debug('Deleting resolved info for interface %i, protocol %i, host %s, aprotocol %i, address %s, port %i' % old_resolved_info[i])
del old_resolved_info[i]
break
resolved_info = resolved_info + old_resolved_info
log.debug('Collected resolved info is now: %s' % (resolved_info,))
self.contacts[name] = (name, domain, resolved_info, bare_name, txt)
self.new_serviceCB(name)
else:
# remember data
# In case this is not our own record but of another
# gajim instance on the same machine,
# it will be used when we get a new name.
self.invalid_self_contact[name] = (name, domain,
(interface, protocol, host, aprotocol, address, port),
bare_name, txt)
# different handler when resolving all contacts
def service_resolved_all_callback(self, interface, protocol, name, stype,
domain, host, aprotocol, address, port, txt, flags):
if not self.connected:
return
bare_name = name
if name.find('@') == -1:
name = name + '@' + name
# update TXT data only, as intended according to resolve_all comment
old_contact = self.contacts[name]
self.contacts[name] = old_contact[0:Constant.TXT] + (txt,) + old_contact[Constant.TXT+1:]
def service_added_callback(self):
log.debug('Service successfully added')
def service_committed_callback(self):
log.debug('Service successfully committed')
def service_updated_callback(self):
log.debug('Service successfully updated')
def service_add_fail_callback(self, err):
log.debug('Error while adding service. %s' % str(err))
if 'Local name collision' in str(err):
alternative_name = self.server.GetAlternativeServiceName(self.username)
self.name_conflictCB(alternative_name)
return
self.error_CB(_('Error while adding service. %s') % str(err))
self.disconnect()
def server_state_changed_callback(self, state, error):
log.debug('server state changed to %s' % state)
if state == self.avahi.SERVER_RUNNING:
self.create_service()
elif state in (self.avahi.SERVER_COLLISION,
self.avahi.SERVER_REGISTERING):
self.disconnect()
self.entrygroup.Reset()
elif state == self.avahi.CLIENT_FAILURE:
# does it ever go here?
log.debug('CLIENT FAILURE')
def entrygroup_state_changed_callback(self, state, error):
# the name is already present, so recreate
if state == self.avahi.ENTRY_GROUP_COLLISION:
log.debug('zeroconf.py: local name collision')
self.service_add_fail_callback('Local name collision')
elif state == self.avahi.ENTRY_GROUP_FAILURE:
self.disconnect()
self.entrygroup.Reset()
log.debug('zeroconf.py: ENTRY_GROUP_FAILURE reached(that'
' should not happen)')
# make zeroconf-valid names
def replace_show(self, show):
if show in ['chat', 'online', '']:
return 'avail'
elif show == 'xa':
return 'away'
return show
def avahi_txt(self):
return self.avahi.dict_to_txt_array(self.txt)
def create_service(self):
try:
if not self.entrygroup:
# create an EntryGroup for publishing
self.entrygroup = dbus.Interface(self.bus.get_object(
self.avahi.DBUS_NAME, self.server.EntryGroupNew()),
self.avahi.DBUS_INTERFACE_ENTRY_GROUP)
self.entrygroup.connect_to_signal('StateChanged',
self.entrygroup_state_changed_callback)
txt = {}
# remove empty keys
for key, val in self.txt.items():
if val:
txt[key] = val
txt['port.p2pj'] = self.port
txt['version'] = 1
txt['txtvers'] = 1
# replace gajim's show messages with compatible ones
if 'status' in self.txt:
txt['status'] = self.replace_show(self.txt['status'])
else:
txt['status'] = 'avail'
self.txt = txt
log.debug('Publishing service %s of type %s' % (self.name,
self.stype))
self.entrygroup.AddService(self.avahi.IF_UNSPEC,
self.avahi.PROTO_UNSPEC, dbus.UInt32(0), self.name, self.stype, '',
'', dbus.UInt16(self.port), self.avahi_txt(),
reply_handler=self.service_added_callback,
error_handler=self.service_add_fail_callback)
self.entrygroup.Commit(reply_handler=self.service_committed_callback,
error_handler=self.entrygroup_commit_error_CB)
return True
except dbus.DBusException as e:
log.debug(str(e))
return False
def announce(self):
if not self.connected:
return False
state = self.server.GetState()
if state == self.avahi.SERVER_RUNNING:
if self.create_service():
self.announced = True
return True
return False
def remove_announce(self):
if self.announced == False:
return False
try:
if self.entrygroup.GetState() != self.avahi.ENTRY_GROUP_FAILURE:
self.entrygroup.Reset()
self.entrygroup.Free()
# .Free() has mem leaks
self.entrygroup._obj._bus = None
self.entrygroup._obj = None
self.entrygroup = None
self.announced = False
return True
else:
return False
except dbus.DBusException:
log.debug("Can't remove service. That should not happen")
def browse_domain(self, interface, protocol, domain):
self.new_service_type(interface, protocol, self.stype, domain, '')
def avahi_dbus_connect_cb(self, a, connect, disconnect):
if connect != "":
log.debug('Lost connection to avahi-daemon')
self.disconnect()
if self.disconnected_CB:
self.disconnected_CB()
else:
log.debug('We are connected to avahi-daemon')
# connect to dbus
def connect_dbus(self):
try:
import dbus
except ImportError:
log.debug('Error: python-dbus needs to be installed. No '
'zeroconf support.')
return False
if self.bus:
return True
try:
self.bus = dbus.SystemBus()
self.bus.add_signal_receiver(self.avahi_dbus_connect_cb,
'NameOwnerChanged', 'org.freedesktop.DBus',
arg0='org.freedesktop.Avahi')
except Exception as e:
# System bus is not present
self.bus = None
log.debug(str(e))
return False
else:
return True
# connect to avahi
def connect_avahi(self):
if not self.connect_dbus():
return False
try:
import avahi
self.avahi = avahi
except ImportError:
log.debug('Error: python-avahi needs to be installed. No '
'zeroconf support.')
return False
if self.server:
return True
try:
self.server = dbus.Interface(self.bus.get_object(self.avahi.DBUS_NAME,
self.avahi.DBUS_PATH_SERVER), self.avahi.DBUS_INTERFACE_SERVER)
self.server.connect_to_signal('StateChanged',
self.server_state_changed_callback)
except Exception as e:
# Avahi service is not present
self.server = None
log.debug(str(e))
return False
else:
return True
def connect(self):
self.name = self.username + '@' + self.host # service name
if not self.connect_avahi():
return False
self.connected = True
# start browsing
if self.domain is None:
# Explicitly browse .local
self.browse_domain(self.avahi.IF_UNSPEC, self.avahi.PROTO_UNSPEC,
'local')
# Browse for other browsable domains
self.domain_browser = dbus.Interface(self.bus.get_object(
self.avahi.DBUS_NAME, self.server.DomainBrowserNew(
self.avahi.IF_UNSPEC, self.avahi.PROTO_UNSPEC, '',
self.avahi.DOMAIN_BROWSER_BROWSE, dbus.UInt32(0))),
self.avahi.DBUS_INTERFACE_DOMAIN_BROWSER)
self.domain_browser.connect_to_signal('ItemNew',
self.new_domain_callback)
self.domain_browser.connect_to_signal('Failure', self.error_callback)
else:
self.browse_domain(self.avahi.IF_UNSPEC, self.avahi.PROTO_UNSPEC,
self.domain)
return True
def disconnect(self):
if self.connected:
self.connected = False
if self.service_browser:
try:
self.service_browser.Free()
except dbus.DBusException as e:
log.debug(str(e))
self.service_browser._obj._bus = None
self.service_browser._obj = None
if self.domain_browser:
try:
self.domain_browser.Free()
except dbus.DBusException as e:
log.debug(str(e))
self.domain_browser._obj._bus = None
self.domain_browser._obj = None
self.remove_announce()
self.server._obj._bus = None
self.server._obj = None
self.server = None
self.service_browser = None
self.domain_browser = None
# refresh txt data of all contacts manually (no callback available)
def resolve_all(self):
if not self.connected:
return
for val in self.contacts.values():
# get txt data from last recorded resolved info
# TODO: Better try to get it from last IPv6 mDNS, then last IPv4?
ri = val[Constant.RESOLVED_INFO][0]
self.server.ResolveService(int(ri[ConstantRI.INTERFACE]), int(ri[ConstantRI.PROTOCOL]),
val[Constant.BARE_NAME], self.stype, val[Constant.DOMAIN],
self.avahi.PROTO_UNSPEC, dbus.UInt32(0),
reply_handler=self.service_resolved_all_callback,
error_handler=self.error_callback)
def get_contacts(self):
return self.contacts
def get_contact(self, jid):
if not jid in self.contacts:
return None
return self.contacts[jid]
def update_txt(self, show = None):
if show:
self.txt['status'] = self.replace_show(show)
txt = self.avahi_txt()
if self.connected and self.entrygroup:
self.entrygroup.UpdateServiceTxt(self.avahi.IF_UNSPEC,
self.avahi.PROTO_UNSPEC, dbus.UInt32(0), self.name, self.stype, '',
txt, reply_handler=self.service_updated_callback,
error_handler=self.error_callback)
return True
else:
return False
# END Zeroconf