class AgpsServer(object):
def __init__(self, conf_file):
ConfHelper.load(conf_file)
self.redis = MyRedis()
self._socket = None
self.get_agps_thread = None
def start(self):
self.__start_get_agps_thread()
try:
self._socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
self._socket.bind((ConfHelper.AGPS_CONF['host'], int(ConfHelper.AGPS_CONF['port'])))
self._socket.listen(int(ConfHelper.AGPS_CONF['count']))
while True:
try:
infds, _, _ = select.select([self._socket,],[],[],1)
if len(infds) > 0:
connection, address = self._socket.accept()
data = connection.recv(1024)
logging.info("[AGPS] Recv %d length request:\n%s", len(data), data)
agps_data = self.handle_request(data)
if agps_data:
connection.send(agps_data)
logging.info("[AGPS] Send response length:%s", len(agps_data))
connection.close()
except KeyboardInterrupt:
logging.error("[AGPS] Ctrl-C is pressed.")
self._socket.close()
except:
logging.exception("[AGPS] Socket exception.")
finally:
try:
self._socket.close()
except:
logging.exception("[AGPS] Socket close exception")
def handle_request(self, data):
try:
packet = T_CLWCheck(data)
command = packet.head.command
if command == GATEWAY.T_MESSAGE_TYPE.AGPS:
head = packet.head
body = packet.body
args = DotDict(success=GATEWAY.RESPONSE_STATUS.SUCCESS,
agps_data=None)
ap = AgpsParser(body, head)
agps_sign = self.get_agps_sign(ap.ret, int(head.timestamp))
if agps_sign != int(head.agps_sign, 16):
args.success = GATEWAY.RESPONSE_STATUS.INVALID_SESSIONID
logging.error("[AGPS] agps_sign invalid.")
else:
agps = ap.ret
args.agps_data = self.get_agps_from_redis(agps)
if args.agps_data:
ac = AgpsComposer(args)
return ac.buf
else:
logging.error("[AGPS] there's no invalid agps data.")
return None
except:
logging.exception("[AGPS] Handle agps request exception.")
return None
def get_agps_sign(self, agps, timestamp):
DEFAULT_KEY = 181084178
lon = int(agps.lon)
lat = int(agps.lat)
agps_sign = DEFAULT_KEY ^ lon ^ lat ^ timestamp
return agps_sign
def get_agps_from_ublox(self):
LON_LAT = GATEWAY.LON_LAT
for key, lon_lat in LON_LAT.items():
u_socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
try:
request = "cmd=aid;user=%s;pwd=%s;lat=%s;lon=%s;pacc=%s\n" % (
ConfHelper.UBLOX_CONF.user,
ConfHelper.UBLOX_CONF.pwd,
lon_lat[1],
lon_lat[0],
ConfHelper.UBLOX_CONF.pacc)
u_socket.connect((ConfHelper.UBLOX_CONF.host, int(ConfHelper.UBLOX_CONF.port)))
u_socket.send(request)
agps_data = self.recv_ublox(u_socket)
agps_key = get_agps_data_key(key)
if agps_data:
self.redis.set(agps_key, base64.b64encode(agps_data))
logging.info("[AGPS] Get agps data [%s] from ublox success.", key)
else:
self.redis.delete(agps_key)
logging.info("[AGPS] Get agps data [%s] from ublox faild.", key)
except:
logging.exception("[AGPS] Get agps from u-blox exception.")
finally:
try:
u_socket.close()
except:
logging.exception("[AGPS] U-blox socket close exception.")
time.sleep(10)
def recv_ublox(self, u_socket):
default_length = 1024
split_str = ("\r\n\r\n")
agps_data = u_socket.recv(default_length)
head = agps_data.split(split_str)[0]
binary_length = int(head.split("\n")[1].split(": ")[1])
logging.info("[AGPS] agps_data length:%d", binary_length)
remain_length = binary_length - (default_length - (len(head) + len(split_str)))
while remain_length:
agps_buf = u_socket.recv(remain_length)
if not agps_buf:
logging.warn("[AGPS] recv empty response of socket!")
u_socket.close()
raise socket.error(errno.EPIPE, "the pipe might be broken.")
agps_data += agps_buf
remain_length -= len(agps_buf)
return agps_data[-binary_length:]
def get_agps_from_redis(self, agps):
try:
logging.info("[AGPS] Terminal lon=%s, lat=%s", agps.lon, agps.lat)
partition_key = self.get_partition_key(float(agps.lon), float(agps.lat))
agps_key = get_agps_data_key(partition_key)
agps_data = self.redis.get(agps_key)
agps_data = agps_data if agps_data else ""
return agps_data
except:
logging.exception("[AGPS] Get agps from redis exception.")
return ""
def get_partition_key(self, lon, lat):
LON_LAT = GATEWAY.LON_LAT
partition_key = "default"
for key, lon_lat in LON_LAT.items():
if abs(float(lon_lat[0]) - lon / 3600000) <= 10 and \
abs(float(lon_lat[1]) - lat / 3600000) <= 12.5:
partition_key = key
break
logging.info("[AGPS] agps partition is:%s", partition_key)
return partition_key
def __start_get_agps_thread(self):
self.get_agps_thread = RepeatedTimer(int(ConfHelper.UBLOX_CONF.interval),
self.get_agps_from_ublox)
self.get_agps_thread.start()
logging.info("[AGPS] Get agps thread is running...")
def __stop_get_agps_thread(self):
if self.get_agps_thread is not None:
self.get_agps_thread.cancel()
self.get_agps_thread.join()
logging.info("[AGPS] Get agps thread stop.")
self.get_agps_thread = None
def stop(self):
self.__stop_get_agps_thread()
self._socket.close()
