from datetime import datetime, timezone
from enum import Enum
from inspect import isclass
-from logging import getLogger
-from struct import pack, unpack
+from struct import error, pack, unpack
__all__ = (
"class_by_prefix",
"inline_response",
- "make_object",
"parse_message",
"proto_by_name",
+ "DecodeError",
"Respond",
"GPS303Pkt",
"UNKNOWN",
"WHITELIST_TOTAL",
"WIFI_OFFLINE_POSITIONING",
"TIME",
+ "PROHIBIT_LBS",
+ "GPS_LBS_SWITCH_TIMES",
+ "REMOTE_MONITOR_PHONE",
+ "SOS_PHONE",
+ "DAD_PHONE",
"MOM_PHONE",
+ "STOP_UPLOAD",
+ "GPS_OFF_PERIOD",
+ "DND_PERIOD",
+ "RESTART_SHUTDOWN",
+ "DEVICE",
+ "ALARM_CLOCK",
"STOP_ALARM",
"SETUP",
"SYNCHRONOUS_WHITELIST",
"CHARGER_DISCONNECTED",
"VIBRATION_RECEIVED",
"POSITION_UPLOAD_INTERVAL",
+ "SOS_ALARM",
+ "UNKNOWN_B3",
)
-log = getLogger("gps303")
+
+class DecodeError(Exception):
+ def __init__(self, e, **kwargs):
+ super().__init__(e)
+ for k, v in kwargs.items():
+ setattr(self, k, v)
+
+def intx(x):
+ if isinstance(x, str):
+ x = int(x, 0)
+ return x
+
+
+def hhmm(x):
+ """Check for the string that represents hours and minutes"""
+ if not isinstance(x, str) or len(x) != 4:
+ raise ValueError(str(x) + " is not a four-character string")
+ hh = int(x[:2])
+ mm = int(x[2:])
+ if hh < 0 or hh > 23 or mm < 0 or mm > 59:
+ raise ValueError(str(x) + " does not contain valid hours and minutes")
+ return x
+
+
+def l3str(x):
+ if isinstance(x, str):
+ x = x.split(",")
+ if len(x) != 3 or not all(isinstance(el, str) for el in x):
+ raise ValueError(str(x) + " is not a list of three strings")
+ return x
+
+
+def l3int(x):
+ if isinstance(x, str):
+ x = x.split(",")
+ x = [int(el) for el in x]
+ if len(x) != 3 or not all(isinstance(el, int) for el in x):
+ raise ValueError(str(x) + " is not a list of three integers")
+ return x
class MetaPkt(type):
def __new__(cls, name, bases, attrs):
newcls = super().__new__(cls, name, bases, attrs)
- nestattrs = {"encode": lambda self: self.in_encode()}
- if "IN_KWARGS" in attrs:
- nestattrs["KWARGS"] = attrs["IN_KWARGS"]
newcls.In = super().__new__(
cls,
name + ".In",
(newcls,) + bases,
- nestattrs,
+ {
+ "KWARGS": newcls.IN_KWARGS,
+ "decode": newcls.in_decode,
+ "encode": newcls.in_encode,
+ },
)
- nestattrs = {"encode": lambda self: self.out_encode()}
- if "OUT_KWARGS" in attrs:
- nestattrs["KWARGS"] = attrs["OUT_KWARGS"]
newcls.Out = super().__new__(
cls,
name + ".Out",
(newcls,) + bases,
- nestattrs,
+ {
+ "KWARGS": newcls.OUT_KWARGS,
+ "decode": newcls.out_decode,
+ "encode": newcls.out_encode,
+ },
)
return newcls
class GPS303Pkt(metaclass=MetaPkt):
RESPOND = Respond.NON # Do not send anything back by default
PROTO: int
- # Have these kwargs for now, TODO redo
- IN_KWARGS = (("length", int, 0), ("payload", bytes, b""))
+ IN_KWARGS = ()
+ OUT_KWARGS = ()
def __init__(self, *args, **kwargs):
- assert len(args) == 0
- for kw, typ, dfl in self.KWARGS:
- setattr(self, kw, typ(kwargs.pop(kw, dfl)))
- if kwargs:
- print("KWARGS", self.KWARGS)
- print("kwargs", kwargs)
- raise TypeError(
- self.__class__.__name__ + " stray kwargs " + str(kwargs)
- )
+ """
+ Construct the object _either_ from (length, payload),
+ _or_ from the values of individual fields
+ """
+ assert not args or (len(args) == 2 and not kwargs)
+ if args: # guaranteed to be two arguments at this point
+ self.length, self.payload = args
+ try:
+ self.decode(self.length, self.payload)
+ except error as e:
+ raise DecodeError(e, obj=self)
+ else:
+ for kw, typ, dfl in self.KWARGS:
+ setattr(self, kw, typ(kwargs.pop(kw, dfl)))
+ if kwargs:
+ raise ValueError(
+ self.__class__.__name__ + " stray kwargs " + str(kwargs)
+ )
def __repr__(self):
return "{}({})".format(
),
)
+ def in_decode(self, length, packet):
+ # Overridden in subclasses, otherwise do not decode payload
+ return
+
+ def out_decode(self, length, packet):
+ # Overridden in subclasses, otherwise do not decode payload
+ return
+
def in_encode(self):
+ # Necessary to emulate terminal, which is not implemented
raise NotImplementedError(
self.__class__.__name__ + ".encode() not implemented"
)
def out_encode(self):
+ # Overridden in subclasses, otherwise make empty payload
return b""
@property
length = len(payload) + 1
return pack("BB", length, self.PROTO) + payload
- @classmethod
- def from_packet(cls, length, payload):
- return cls.In(payload=payload, length=length)
-
class UNKNOWN(GPS303Pkt):
PROTO = 256 # > 255 is impossible in real packets
RESPOND = Respond.INL
# Default response for ACK, can also respond with STOP_UPLOAD
- @classmethod
- def from_packet(cls, length, payload):
- self = super().from_packet(length, payload)
+ def in_decode(self, length, payload):
self.imei = payload[:-1].hex()
self.ver = unpack("B", payload[-1:])[0]
return self
class _GPS_POSITIONING(GPS303Pkt):
RESPOND = Respond.INL
- @classmethod
- def from_packet(cls, length, payload):
- self = super().from_packet(length, payload)
+ def in_decode(self, length, payload):
self.dtime = payload[:6]
if self.dtime == b"\0\0\0\0\0\0":
self.devtime = None
else:
+ yr, mo, da, hr, mi, se = unpack("BBBBBB", self.dtime)
self.devtime = datetime(
- *unpack("BBBBBB", self.dtime), tzinfo=timezone.utc
+ 2000 + yr, mo, da, hr, mi, se, tzinfo=timezone.utc
)
self.gps_data_length = payload[6] >> 4
self.gps_nb_sat = payload[6] & 0x0F
flip_lat = not bool(flags & 0b0000010000000000) # bit 5
self.heading = flags & 0b0000001111111111 # bits 6 - last
self.latitude = lat / (30000 * 60) * (-1 if flip_lat else 1)
- self.longitude = lon / (30000 * 60) * (-2 if flip_lon else 1)
+ self.longitude = lon / (30000 * 60) * (-1 if flip_lon else 1)
self.speed = speed
self.flags = flags
return self
RESPOND = Respond.EXT
OUT_KWARGS = (("upload_interval", int, 25),)
- @classmethod
- def from_packet(cls, length, payload):
- self = super().from_packet(length, payload)
- if len(payload) == 5:
- (
- self.batt,
- self.ver,
- self.timezone,
- self.intvl,
- self.signal,
- ) = unpack("BBBBB", payload)
- elif len(payload) == 4:
- self.batt, self.ver, self.timezone, self.intvl = unpack(
- "BBBB", payload
- )
+ def in_decode(self, length, payload):
+ self.batt, self.ver, self.timezone, self.intvl = unpack(
+ "BBBB", payload[:4]
+ )
+ if len(payload) > 4:
+ self.signal = payload[4]
+ else:
self.signal = None
return self
def out_encode(self): # Set interval in minutes
- return cls.make_packet(pack("B", self.upload_interval))
+ return pack("B", self.upload_interval)
class HIBERNATION(GPS303Pkt): # Server can send to send devicee to sleep
PROTO = 0x14
- RESPOND = Respond.INL
class RESET(GPS303Pkt):
class _WIFI_POSITIONING(GPS303Pkt):
- @classmethod
- def from_packet(cls, length, payload):
- self = super().from_packet(length, payload)
+ def in_decode(self, length, payload):
self.dtime = payload[:6]
if self.dtime == b"\0\0\0\0\0\0":
self.devtime = None
class GPS_OFF_PERIOD(GPS303Pkt):
PROTO = 0x46
- OUT_KWARGS = (("onoff", int, 0), ("fm", str, "0000"), ("to", str, "2359"))
+ OUT_KWARGS = (
+ ("onoff", int, 0),
+ ("fm", hhmm, "0000"),
+ ("to", hhmm, "2359"),
+ )
def out_encode(self):
return (
OUT_KWARGS = (
("onoff", int, 0),
("week", int, 3),
- ("fm1", str, "0000"),
- ("to1", str, "2359"),
- ("fm2", str, "0000"),
- ("to2", str, "2359"),
+ ("fm1", hhmm, "0000"),
+ ("to1", hhmm, "2359"),
+ ("fm2", hhmm, "0000"),
+ ("to2", hhmm, "2359"),
)
def out_endode(self):
class RESTART_SHUTDOWN(GPS303Pkt):
PROTO = 0x48
- OUT_KWARGS = (("flag", int, 2),)
+ OUT_KWARGS = (("flag", int, 0),)
def out_encode(self):
# 1 - restart
class STOP_ALARM(GPS303Pkt):
PROTO = 0x56
- @classmethod
- def from_packet(cls, length, payload):
- self = super().from_packet(length, payload)
+ def in_decode(self, length, payload):
self.flag = payload[0]
return self
class SETUP(GPS303Pkt):
PROTO = 0x57
RESPOND = Respond.EXT
- OUT_KWARGS = ( # TODO handle properly
- ("uploadintervalseconds", int, 0x0300),
- ("binaryswitch", int, 0b00110001),
- ("alarms", int, [0, 0, 0]),
+ OUT_KWARGS = (
+ ("uploadintervalseconds", intx, 0x0300),
+ ("binaryswitch", intx, 0b00110001),
+ ("alarms", l3int, [0, 0, 0]),
("dndtimeswitch", int, 0),
- ("dndtimes", int, [0, 0, 0]),
+ ("dndtimes", l3int, [0, 0, 0]),
("gpstimeswitch", int, 0),
("gpstimestart", int, 0),
("gpstimestop", int, 0),
- ("phonenumbers", int, ["", "", ""]),
+ ("phonenumbers", l3str, ["", "", ""]),
)
def out_encode(self):
class WIFI_POSITIONING(_WIFI_POSITIONING):
PROTO = 0x69
RESPOND = Respond.EXT
- OUT_KWARGS = (("lat", float, None), ("lon", float, None))
+ OUT_KWARGS = (("latitude", float, None), ("longitude", float, None))
def out_encode(self):
- if self.lat is None or self.lon is None:
+ if self.latitude is None or self.longitude is None:
return b""
- return "{:+#010.8g},{:+#010.8g}".format(self.lat, self.lon).encode()
+ return "{:+#010.8g},{:+#010.8g}".format(
+ self.latitude, self.longitude
+ ).encode()
+
+ def out_decode(self, length, payload):
+ lat, lon = payload.decode().split(",")
+ self.latitude = float(lat)
+ self.longitude = float(lon)
class MANUAL_POSITIONING(GPS303Pkt):
PROTO = 0x80
- @classmethod
- def from_packet(cls, length, payload):
- self = super().from_packet(length, payload)
+ def in_decode(self, length, payload):
self.flag = payload[0] if len(payload) > 0 else None
self.reason = {
1: "Incorrect time",
RESPOND = Respond.EXT
OUT_KWARGS = (("interval", int, 10),)
- @classmethod
- def from_packet(cls, length, payload):
- self = super().from_packet(length, payload)
+ def in_decode(self, length, payload):
self.interval = unpack("!H", payload[:2])
return self
PROTO = 0x99
+class UNKNOWN_B3(GPS303Pkt):
+ PROTO = 0xB3
+ IN_KWARGS = (("asciidata", str, ""),)
+
+ def in_decode(self, length, payload):
+ self.asciidata = payload.decode()
+ return self
+
+
# Build dicts protocol number -> class and class name -> protocol number
CLASSES = {}
PROTOS = {}
return None
-def make_object(length, proto, payload):
- if proto in CLASSES:
- return CLASSES[proto].from_packet(length, payload)
- else:
- retobj = UNKNOWN.from_packet(length, payload)
- retobj.PROTO = proto # Override class attr with object attr
- return retobj
-
-
-def parse_message(packet):
+def parse_message(packet, is_incoming=True):
+ """From a packet (without framing bytes) derive the XXX.In object"""
length, proto = unpack("BB", packet[:2])
payload = packet[2:]
- adjust = 2 if proto == STATUS.PROTO else 4 # Weird special case
- if (
- proto not in (WIFI_POSITIONING.PROTO, WIFI_OFFLINE_POSITIONING.PROTO)
- and length > 1
- and len(payload) + adjust != length
- ):
- log.warning(
- "With proto %d length is %d but payload length is %d+%d",
- proto,
- length,
- len(payload),
- adjust,
- )
- return make_object(length, proto, payload)
+ if proto not in CLASSES:
+ cause = ValueError(f"Proto {proto} is unknown")
+ else:
+ try:
+ if is_incoming:
+ return CLASSES[proto].In(length, payload)
+ else:
+ return CLASSES[proto].Out(length, payload)
+ except DecodeError as e:
+ cause = e
+ if is_incoming:
+ retobj = UNKNOWN.In(length, payload)
+ else:
+ retobj = UNKNOWN.Out(length, payload)
+ retobj.PROTO = proto # Override class attr with object attr
+ retobj.cause = cause
+ return retobj