def __init__(self, user_name,
application_name,
service_name,
service_location):
assert(user_name != "")
assert(application_name != "")
assert(service_name != "")
assert(service_location != "")
# Each instance of this object creates it's own identity.
# This means we generate an UUID here and it is used
# to identify this object (and it's caller) uniquely.
self.user_name = user_name
self.application_name = application_name
self.service_name = service_name
self.service_location = service_location
self.uuid = uuid.uuid4()
self.udp = udplib.UDP()
self.period = DiscoveryServer.period
# Verify the location makes sense, syntactically
location_check = location.check_location(service_location)
assert(location_check is True)
self.alive = True
self.thread = threading.Thread(target=self.__thread_entry)
self.thread.daemon = True
self.thread.start()
def __process_beacon(self, beacon):
pieces = beacon.split()
if len(pieces) != 6:
Llog.LogError("Invalid beacon received: " + beacon)
return
if pieces[0] != "BEACON":
Llog.LogError("Invalid beacon header received: " + beacon)
return
Llog.LogDebug("Beacon: <" + beacon + ">")
#
# We have a valid beacon frame.
# Process the services to see if there are any
# new services contained that we do not have in
# our discovered_services_list.
#
service_uuid, \
user_name, \
application_name, \
service_name, \
service_location = pieces[1:6]
# Attempt to parse the UUID string to ensure it is well-formed
try:
r_uuid = uuid.UUID(service_uuid)
except ValueError:
# The UUID was most likely malformed in the beacon.
# Just discard this beacon.
Llog.LogError("Malformed UUID string: " + service_uuid)
return
# Lets make sure the location meets our expectations
# for format
location_check = location.check_location(service_location)
if location_check is False:
Llog.LogError("Malformed/invalid location!: " + service_location)
return
new_service = DiscoveryService(user_name,
application_name,
service_name,
service_location,
service_uuid)
# Check to see if we already have this entry in our internal
# list of services
service = self.find_discovered_service(new_service)
if service is None:
# Service does not already exist in our list, add it.
# Timestamp the discovered service so we can
# remove them if they expire.
self.discovered_service_list.append(new_service)
# Callout to notify the user of this new service
if self.service_add_cback is not None:
self.service_add_cback(new_service)
else:
# The service exists. Update the timestamp
# in the service entry to keep it from
# expiring
service.time = time.time()