def redirect_or_pass_by_id(self, host_id):
"""
Check if given host id is own host, if not then raise exception
to redirect message to proper destination.
"""
if host_id is None:
raise exceptions.ServiceBusException("Unknown address")
ownip = host_id == self.DAEMON.ID
if not ownip:
raise RedirectRequiredEx(host_id)
def handle_sync_call(self, msgdata):
"""
This is main function to process all requests.
"""
name = msgdata['service']
# not our task
if name != self.servicename:
raise exceptions.ServiceBusException(
"Wrong service task received %s" % str(service))
# not in working state
if self.status != 2:
raise exceptions.ServiceBusException("Worker is currently offline")
#msgdata = self.prepare_message(msgdata)
result = self.run_task(funcname=msgdata['method'],
args=msgdata['args'],
kwargs=msgdata['kwargs'])
#result = self.postprocess_message(result)
return result
def _find_worker(self, service_name, method=None):
"""
Ask kasaya daemon where is service
"""
kasaya = KasayaLocalClient()
msg = kasaya.query( service_name )
if not msg['message']==messages.WORKER_ADDR:
raise exceptions.ServiceBusException("Wrong response from sync server")
addr = msg['addr']
if addr is None:
raise exceptions.ServiceNotFound("No service '%s' found" % service_name)
return addr
def send_and_receive_response(address, message, timeout=10):
"""
j.w. ale dekoduje wynik i go zwraca, lub rzuca otrzymany w wiadomości exception
"""
result = send_and_receive(address, message, timeout)
typ = result['message']
if typ == messages.RESULT:
return result['result']
elif typ == messages.ERROR:
e = exception_deserialize(result)
if e is None:
raise exceptions.MessageCorrupted()
raise e
else:
raise exceptions.ServiceBusException("Wrong message type received")
def decode_header(self, packet):
if len(packet) < self.header.size:
raise exceptions.MessageCorrupted()
busname, ver, psize, iv, cmpr, trim, resreq = self.header.unpack(
packet)
# not our service bus
if busname != self._busname:
raise exceptions.NotOurMessage()
# check protocol version
if ver != self._version:
raise exceptions.ServiceBusException(
"Unknown service bus protocol version")
return (psize, iv, cmpr, trim, resreq)
def CTL_service_stop(self, name, ip=None):
"""
Stop all workers serving given service.
name - name of service to stop
"""
if ip is None:
ip = self.own_ip
self.redirect_or_pass_by_id(ip)
services = []
for wrk in self.DB.worker_list_local():
if wrk['service'] == name:
services.append(wrk['ID'])
if len(services) == 0:
raise exceptions.ServiceBusException(
"There is no [%s] service running" % name)
for u in services:
self.CTL_worker_stop(u)
def CTL_service_start(self, name, ip=None):
"""
Start service on host, or locally if host is not given.
name - name of service to start
ip - ip address of host on which service shoult be started,
if not given then worker will be started on localhost.
"""
if ip is None:
ip = self.own_ip
self.redirect_or_pass_by_id(ip)
try:
svc = self.get_service_ctl(name)
except KeyError:
raise exceptions.ServiceBusException(
"There is no service [%s] on this host" % name)
svc.start_service()
return True
def exception_deserialize(msg):
"""
Deserialize exception from message into exception object which can be raised.
#If message doesn't contains exception, then result will be None.
"""
if msg['internal']:
e = exceptions.ServiceBusException(msg['description'])
else:
e = Exception(msg['description'])
try:
e.name = msg['name']
except KeyError:
e.name = "Exception"
try:
tb = msg['traceback']
except KeyError:
tb = None
if not tb is None:
e.traceback = tb
return e
