2 Implementation of the protocol "beesure" used by some watch-trackers
3 https://www.4p-touch.com/beesure-gps-setracker-server-protocol.html
6 from datetime import datetime, timezone
8 from inspect import isclass
10 from struct import error, pack, unpack
23 from types import SimpleNamespace
44 MAXBUFFER: int = 65557 # Theoretical max buffer 65536 + 21
45 RE = re.compile(b"\[(\w\w)\*(\d{10})\*([0-9a-fA-F]{4})\*")
48 def _framestart(buffer: bytes) -> Tuple[int, str, str, int]:
50 Find the start of the frame in the buffer.
51 If found, return (offset, vendorId, imei, datalen) tuple.
52 If not found, set -1 as the value of `offset`
54 mo = RE.search(buffer)
68 def __init__(self) -> None:
70 self.imei: Optional[str] = None
73 def recv(self, segment: bytes) -> List[Union[bytes, str]]:
75 Process next segment of the stream. Return successfully deframed
76 packets as `bytes` and error messages as `str`.
79 self.buffer += segment
80 if len(self.buffer) > MAXBUFFER:
81 # We are receiving junk. Let's drop it or we run out of memory.
83 return [f"More than {MAXBUFFER} unparseable data, dropping"]
84 msgs: List[Union[bytes, str]] = []
86 if not self.datalen: # we have not seen packet start yet
87 toskip, _, imei, datalen = _framestart(self.buffer)
88 if toskip < 0: # No frames, continue reading
90 if toskip > 0: # Should not happen, report
92 f"Skipping {toskip} bytes of undecodable data"
93 f' "{self.buffer[:toskip][:64]=!r}"'
95 self.buffer = self.buffer[toskip:]
96 # From this point, buffer starts with a packet header
101 f"Packet's imei {imei} mismatches"
102 f" previous value {self.imei}, old value kept"
104 self.datalen = datalen
105 if len(self.buffer) < self.datalen + 21: # Incomplete packet
107 # At least one complete packet is present in the buffer
108 if chr(self.buffer[self.datalen + 20]) == "]":
109 msgs.append(self.buffer[: self.datalen + 21])
112 f"Packet does not end with ']'"
113 f" at {self.datalen+20}: {self.buffer=!r}"
115 self.buffer = self.buffer[self.datalen + 21 :]
119 def close(self) -> bytes:
127 def enframe(buffer: bytes, imei: Optional[str] = None) -> bytes:
128 assert imei is not None and len(imei) == 10
129 off, vid, _, dlen = _framestart(buffer)
131 return f"[{vid:2s}*{imei:10s}*{dlen:04X}*".encode() + buffer[20:]
134 ### Parser/Constructor ###
137 class DecodeError(Exception):
138 def __init__(self, e: Exception, **kwargs: Any) -> None:
140 for k, v in kwargs.items():
144 def maybe(typ: type) -> Callable[[Any], Any]:
145 return lambda x: None if x is None else typ(x)
148 def intx(x: Union[str, int]) -> int:
149 if isinstance(x, str):
154 def boolx(x: Union[str, bool]) -> bool:
155 if isinstance(x, str):
156 if x.upper() in ("ON", "TRUE", "1"):
158 if x.upper() in ("OFF", "FALSE", "0"):
160 raise ValueError(str(x) + " could not be parsed as a Boolean")
164 def l3str(x: Union[str, List[str]]) -> List[str]:
165 if isinstance(x, str):
169 if len(lx) != 3 or not all(isinstance(el, str) for el in x):
170 raise ValueError(str(lx) + " is not a list of three strings")
176 For each class corresponding to a message, automatically create
177 two nested classes `In` and `Out` that also inherit from their
178 "nest". Class attribute `IN_KWARGS` defined in the "nest" is
179 copied to the `In` nested class under the name `KWARGS`, and
180 likewise, `OUT_KWARGS` of the nest class is copied as `KWARGS`
181 to the nested class `Out`. In addition, method `encode` is
182 defined in both classes equal to `in_encode()` and `out_encode()`
188 def __getattr__(self, name: str) -> Any:
191 def __setattr__(self, name: str, value: Any) -> None:
195 cls: Type["MetaPkt"],
197 bases: Tuple[type, ...],
198 attrs: Dict[str, Any],
200 newcls = super().__new__(cls, name, bases, attrs)
201 newcls.In = super().__new__(
206 "KWARGS": newcls.IN_KWARGS,
207 "decode": newcls.in_decode,
208 "encode": newcls.in_encode,
211 newcls.Out = super().__new__(
216 "KWARGS": newcls.OUT_KWARGS,
217 "decode": newcls.out_decode,
218 "encode": newcls.out_encode,
225 NON = 0 # Incoming, no response needed
226 INL = 1 # Birirectional, use `inline_response()`
227 EXT = 2 # Birirectional, use external responder
230 class BeeSurePkt(metaclass=MetaPkt):
231 RESPOND = Respond.NON # Do not send anything back by default
232 IN_KWARGS: Tuple[Tuple[str, Callable[[Any], Any], Any], ...] = ()
233 OUT_KWARGS: Tuple[Tuple[str, Callable[[Any], Any], Any], ...] = ()
234 KWARGS: Tuple[Tuple[str, Callable[[Any], Any], Any], ...] = ()
235 In: Type["BeeSurePkt"]
236 Out: Type["BeeSurePkt"]
240 def __getattr__(self, name: str) -> Any:
243 def __setattr__(self, name: str, value: Any) -> None:
246 def __init__(self, *args: Any, **kwargs: Any):
248 Construct the object _either_ from (length, payload),
249 _or_ from the values of individual fields
251 assert not args or (len(args) == 4 and not kwargs)
252 if args: # guaranteed to be two arguments at this point
253 self.vendor, self.imei, self.datalength, self.payload = args
255 self.decode(*self.payload)
257 raise DecodeError(e, obj=self)
259 for kw, typ, dfl in self.KWARGS:
260 setattr(self, kw, typ(kwargs.pop(kw, dfl)))
263 self.__class__.__name__ + " stray kwargs " + str(kwargs)
266 def __repr__(self) -> str:
267 return "{}({})".format(
268 self.__class__.__name__,
272 'bytes.fromhex("{}")'.format(v.hex())
273 if isinstance(v, bytes)
276 for k, v in self.__dict__.items()
277 if not k.startswith("_")
281 def decode(self, *args: str) -> None:
284 def in_decode(self, *args: str) -> None:
285 # Overridden in subclasses, otherwise do not decode payload
288 def out_decode(self, *args: str) -> None:
289 # Overridden in subclasses, otherwise do not decode payload
292 def encode(self) -> str:
295 def in_encode(self) -> str:
296 # Necessary to emulate terminal, which is not implemented
297 raise NotImplementedError(
298 self.__class__.__name__ + ".encode() not implemented"
301 def out_encode(self) -> str:
302 # Overridden in subclasses, otherwise command verb only
306 def PROTO(self) -> str:
308 proto, _ = self.__class__.__name__.split(".")
310 proto = self.__class__.__name__
314 def packed(self) -> bytes:
316 payload = self.PROTO + "," + data if data else self.PROTO
317 return f"[LT*0000000000*{len(payload):04X}*{payload}]".encode()
320 class UNKNOWN(BeeSurePkt):
324 class LK(BeeSurePkt):
325 RESPOND = Respond.INL
327 def in_decode(self, *args: str) -> None:
332 self.tumbling_number = args[2]
334 self.battery_percentage = args[3]
336 def in_encode(self) -> str:
340 class CONFIG(BeeSurePkt):
344 class ICCID(BeeSurePkt):
348 class _LOC_DATA(BeeSurePkt):
349 def in_decode(self, *args: str) -> None:
350 p = SimpleNamespace()
352 for (obj, attr, func), val in zip(
357 (self, "gps_valid", lambda x: x == "A"),
359 (p, "nors", lambda x: 1 if x == "N" else -1),
361 (p, "eorw", lambda x: 1 if x == "E" else -1),
362 (self, "speed", float),
363 (self, "direction", float),
364 (self, "altitude", float),
365 (self, "num_of_sats", int),
366 (self, "gsm_strength_percentage", int),
367 (self, "battery_percentage", int),
368 (self, "pedometer", int),
369 (self, "tubmling_times", int),
370 (self, "device_status", lambda x: int(x, 16)),
371 (self, "base_stations_number", int),
372 (self, "connect_base_station_number", int),
378 setattr(obj, attr, func(val)) # type: ignore
379 rest_args = args[21:]
380 # (area_id, cell_id, strength)*
381 self.base_stations = [
382 tuple(int(el) for el in rest_args[i * 3 : 3 + i * 3])
383 for i in range(self.base_stations_number)
385 rest_args = rest_args[3 * self.base_stations_number :]
386 self.wifi_aps_number = int(rest_args[0])
387 # (SSID, MAC, strength)*
390 rest_args[1 + i * 3],
391 rest_args[2 + i * 3],
392 int(rest_args[3 + i * 3]),
394 for i in range(self.wifi_aps_number)
396 rest_args = rest_args[1 + 3 * self.wifi_aps_number :]
397 self.positioning_accuracy = float(rest_args[0])
403 # .replace(tzinfo=timezone.utc)
404 # .astimezone(tz=timezone.utc)
406 self.latitude = p.lat * p.nors
407 self.longitude = p.lon * p.eorw
414 class UD2(_LOC_DATA):
418 class TKQ(BeeSurePkt):
419 RESPOND = Respond.INL
422 class TKQ2(BeeSurePkt):
423 RESPOND = Respond.INL
427 RESPOND = Respond.INL
430 class CR(BeeSurePkt):
434 class FLOWER(BeeSurePkt):
435 OUT_KWARGS = (("number", int, 1),)
437 def out_encode(self) -> str:
439 return str(self.number)
442 class POWEROFF(BeeSurePkt):
446 class RESET(BeeSurePkt):
450 class SOS(BeeSurePkt):
451 OUT_KWARGS = (("phonenumbers", l3str, ["", "", ""]),)
453 def out_encode(self) -> str:
454 self.phonenumbers: List[str]
455 return ",".join(self.phonenumbers)
458 class _SET_PHONE(BeeSurePkt):
459 OUT_KWARGS = (("phonenumber", str, ""),)
461 def out_encode(self) -> str:
462 self.phonenumber: str
463 return self.phonenumber
466 class SOS1(_SET_PHONE):
470 class SOS2(_SET_PHONE):
474 class SOS3(_SET_PHONE):
478 # Build dicts protocol number -> class and class name -> protocol number
480 if True: # just to indent the code, sorry!
483 for name, cls in globals().items()
485 and issubclass(cls, BeeSurePkt)
486 and not name.startswith("_")
488 CLASSES[cls.__name__] = cls
493 ) -> Union[Type[BeeSurePkt], List[str]]:
494 if prefix.startswith(PROTO_PREFIX):
495 pname = prefix[len(PROTO_PREFIX) :].upper()
497 raise KeyError(pname)
498 lst = [name for name in CLASSES.keys() if name.upper().startswith(pname)]
500 if len(lst) == 1: # unique prefix match
501 return CLASSES[proto]
502 if proto == pname: # exact match
503 return CLASSES[proto]
507 def proto_handled(proto: str) -> bool:
508 return proto.startswith(PROTO_PREFIX)
511 def proto_name(obj: Union[MetaPkt, BeeSurePkt]) -> str:
512 return PROTO_PREFIX + (
513 obj.__class__.__name__ if isinstance(obj, BeeSurePkt) else obj.__name__
517 def proto_of_message(packet: bytes) -> str:
518 return PROTO_PREFIX + packet[20:-1].split(b",")[0].decode()
521 def imei_from_packet(packet: bytes) -> Optional[str]:
522 toskip, _, imei, _ = _framestart(packet)
523 if toskip == 0 and imei != "":
528 def is_goodbye_packet(packet: bytes) -> bool:
532 def inline_response(packet: bytes) -> Optional[bytes]:
533 proto = packet[20:-1].split(b",")[0].decode()
536 if cls.RESPOND is Respond.INL:
537 return cls.Out().packed
541 def probe_buffer(buffer: bytes) -> bool:
542 return bool(RE.search(buffer))
545 def parse_message(packet: bytes, is_incoming: bool = True) -> BeeSurePkt:
546 """From a packet (without framing bytes) derive the XXX.In object"""
547 toskip, vendor, imei, datalength = _framestart(packet)
548 payload = packet[20:-1].decode().split(",")
549 proto = payload[0] if len(payload) > 0 else ""
550 if proto not in CLASSES:
551 cause: Union[DecodeError, ValueError, IndexError] = ValueError(
552 f"Proto {proto} is unknown"
557 return CLASSES[proto].In(vendor, imei, datalength, payload)
559 return CLASSES[proto].Out(vendor, imei, datalength, payload)
560 except (DecodeError, ValueError, IndexError) as e:
563 retobj = UNKNOWN.In(vendor, imei, datalength, payload)
565 retobj = UNKNOWN.Out(vendor, imei, datalength, payload)
566 retobj.proto = proto # Override class attr with object attr
571 def exposed_protos() -> List[Tuple[str, bool]]:
573 (proto_name(UD), True),
574 (proto_name(UD2), False),