initial import of zeroconf class (standalone)

src/zeroconf.py

+#!/usr/bin/python
+
+import os, sys
+
+try:
+	import avahi, gobject, dbus
+except ImportError:
+	print "Error: python-avahi and python-dbus need to be installed. No zeroconf support."
+
+try:
+	import dbus.glib
+except ImportError, e:
+	pass
+
+service_browsers = {}
+
+class Zeroconf:
+	def __init__(self, name):
+		self.domain = None   # specific domain to browse
+		self.stype = '_presence._tcp'
+		self.port = 5298  # listening port that gets announced
+		self.name = name  # service name / username
+		self.txt = {}
+
+		self.contacts = {}    # all current local contacts with data
+		self.entrygroup = ''
+		
+	## handlers for dbus callbacks
+
+	# error handler - maybe replace with gui version/gajim facilities
+	def print_error_callback(self, err):
+		print "Error:", str(err)
+
+	def new_service_callback(self, interface, protocol, name, stype, domain, flags):
+		print "Found service '%s' in domain '%s' on %i.%i." % (name, domain, interface, protocol)
+
+		#synchronous resolving
+		self.server.ResolveService( int(interface), int(protocol), name, stype, domain, avahi.PROTO_UNSPEC, dbus.UInt32(0), reply_handler=self.service_resolved_callback, error_handler=self.print_error_callback)
+
+	def remove_service_callback(self, interface, protocol, name, stype, domain, flags):
+		print "Service '%s' in domain '%s' on %i.%i disappeared." % (name, domain, interface, protocol)
+		del self.contacts[(interface, name, domain)]
+
+	def new_service_type(self, interface, protocol, stype, domain, flags):
+		global service_browsers
+
+		# Are we already browsing this domain for this type? 
+		if service_browsers.has_key((interface, protocol, stype, domain)):
+			return
+
+		print "Browsing for services of type '%s' in domain '%s' on %i.%i ..." % (stype, domain, interface, protocol)
+
+		b = dbus.Interface(self.bus.get_object(avahi.DBUS_NAME, \
+				self.server.ServiceBrowserNew(interface, protocol, \
+				stype, domain, dbus.UInt32(0))),avahi.DBUS_INTERFACE_SERVICE_BROWSER)
+		b.connect_to_signal('ItemNew', self.new_service_callback)
+		b.connect_to_signal('ItemRemove', self.remove_service_callback)
+
+		service_browsers[(interface, protocol, stype, domain)] = b
+
+	def new_domain_callback(self,interface, protocol, domain, flags):
+		if domain != "local":
+			self.browse_domain(interface, protocol, domain)
+
+	def service_resolved_callback(self, interface, protocol, name, stype, domain, host, aprotocol, address, port, txt, flags):
+			print "Service data for service '%s' in domain '%s' on %i.%i:" % (name, domain, interface, protocol)
+			print "\tHost %s (%s), port %i, TXT data: %s" % (host, address, port, str(avahi.txt_array_to_string_array(txt)))
+
+			self.contacts[(interface, name, domain)] = (interface, name, protocol, domain, host, address, port, txt)
+
+
+	def service_added_callback(self):
+		print "Service successfully added"
+	
+	def service_committed_callback(self):
+		print "Service successfully committed"
+		
+	def service_updated_callback(self):
+		print "Service successfully updated"
+
+	def service_add_fail_callback(self, err):
+		print "Error while adding service:", str(err)
+		self.name = self.server.GetAlternativeServiceName(self.name)
+		self.create_service()
+	
+	def server_state_changed_callback(self, state, error):
+		print "server.state %s" % state
+		if state == avahi.SERVER_RUNNING:
+			self.create_service()
+		elif state == avahi.SERVER_COLLISION:
+			self.entrygroup.Reset()
+#		elif state == avahi.CLIENT_FAILURE:           # TODO: add error handling (avahi daemon dies...?)
+		
+	def entrygroup_state_changed_callback(self, state, error):
+		# the name is already present, so ...
+		if state == avahi.ENTRY_GROUP_COLLISION:
+			print "Collision with existing service of name %s" % self.name
+			# ... get a new one and recreate the service
+			self.name = self.server.GetAlternativeServiceName(self.name)
+			self.create_service()
+#		elif state == avahi.ENTRY_GROUP_FAILURE:
+
+	def create_service(self):
+		if self.entrygroup == '':
+			# create an EntryGroup for publishing
+			self.entrygroup = dbus.Interface(self.bus.get_object(avahi.DBUS_NAME, self.server.EntryGroupNew()), avahi.DBUS_INTERFACE_ENTRY_GROUP)
+			self.entrygroup.connect_to_signal('StateChanged', self.entrygroup_state_changed_callback)
+				
+		self.txt[('port.p2pj')] = self.port
+		self.txt[('version')] = 1
+		self.txt[('textvers')] = 1
+
+		print "Publishing service '%s' of type %s" % (self.name, self.stype)
+		self.entrygroup.AddService(avahi.IF_UNSPEC, avahi.PROTO_UNSPEC, dbus.UInt32(0), self.name, self.stype, '', '', self.port, avahi.dict_to_txt_array(self.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.print_error_callback)
+		
+	def publish(self):
+		state = self.server.GetState()
+
+		if state == avahi.SERVER_RUNNING:
+			self.create_service()
+		
+	def remove_announce(self):
+		self.entrygroup.Reset()
+		self.entrygroup.Free()
+
+	def browse_domain(self, interface, protocol, domain):
+		self.new_service_type(interface, protocol, self.stype, domain, '')
+	
+	# connect to dbus
+	def connect(self):
+		self.bus = dbus.SystemBus()
+		self.server = dbus.Interface(self.bus.get_object(avahi.DBUS_NAME, \
+			avahi.DBUS_PATH_SERVER), avahi.DBUS_INTERFACE_SERVER)
+
+		self.server.connect_to_signal('StateChanged', self.server_state_changed_callback)
+		
+		# start browsing
+		if self.domain is None:
+			# Explicitly browse .local
+			self.browse_domain(avahi.IF_UNSPEC, avahi.PROTO_UNSPEC, "local")
+
+			# Browse for other browsable domains
+			db = dbus.Interface(self.bus.get_object(avahi.DBUS_NAME, \
+					self.server.DomainBrowserNew(avahi.IF_UNSPEC, \
+					avahi.PROTO_UNSPEC, '', avahi.DOMAIN_BROWSER_BROWSE,\
+					dbus.UInt32(0))), avahi.DBUS_INTERFACE_DOMAIN_BROWSER)
+			db.connect_to_signal('ItemNew', self.new_domain_callback)
+		else:
+			# Just browse the domain the user wants us to browse
+			self.browse_domain(avahi.IF_UNSPEC, avahi.PROTO_UNSPEC, domain)
+
+#   def disconnect:
+#       necessary ?
+
+	# refresh data manually - really ok or too much traffic?
+	def resolve_all(self):
+		for key in contacts.keys():
+			self.server.ResolveService( int(key.interface), int(key.protocol), key.name, \
+				self.stype, key.domain, avahi.PROTO_UNSPEC, dbus.UInt32(0),\
+				reply_handler=self.service_resolved_callback, error_handler=self.print_error_callback)
+
+	def get_contacts(self):
+		self.resolve_all
+		return self.contacts
+
+	def	set_status(self, status):
+		self.txt[('status')] = status
+		txt = avahi.dict_to_txt_array(self.txt)
+
+		self.entrygroup.UpdateServiceTxt(avahi.IF_UNSPEC, avahi.PROTO_UNSPEC, dbus.UInt32(0), self.name, self.stype,'', txt, reply_handler=self.service_updated_callback, error_handler=self.print_error_callback)
+#		self.entrygroup.Commit()         # TODO: necessary?
+
+def main():
+
+	zeroconf = Zeroconf('foo')
+	zeroconf.connect()
+	zeroconf.txt[('last')] = 'foo'
+	zeroconf.publish()
+	zeroconf.set_status('avail')
+	
+	try:
+		gobject.MainLoop().run()
+	except KeyboardInterrupt, k:
+		pass
+
+if __name__ == "__main__":
+	main()