import os import 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 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.service_browsers = {} 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): # Are we already browsing this domain for this type? if self.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) self.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? # END Zeroconf ''' 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() '''