loctrkd/rectifier.py

   1 """ Estimate coordinates from WIFI_POSITIONING and send back """
   2
   3 from configparser import ConfigParser
   4 from datetime import datetime, timezone
   5 from importlib import import_module
   6 from logging import getLogger
   7 from os import umask
   8 from struct import pack
   9 from typing import cast, List, Tuple
  10 import zmq
  11
  12 from . import common
  13 from .common import CoordReport, HintReport, StatusReport, Report
  14 from .zmsg import Bcast, Rept, Resp, topic
  15
  16 log = getLogger("loctrkd/rectifier")
  17
  18
  19 class QryModule:
  20     @staticmethod
  21     def init(conf: ConfigParser) -> None:
  22         ...
  23
  24     @staticmethod
  25     def shut() -> None:
  26         ...
  27
  28     @staticmethod
  29     def lookup(
  30         mcc: int,
  31         mnc: int,
  32         gsm_cells: List[Tuple[int, int, int]],
  33         wifi_aps: List[Tuple[str, int]],
  34     ) -> Tuple[float, float]:
  35         ...
  36
  37
  38 def runserver(conf: ConfigParser) -> None:
  39     qry = cast(
  40         QryModule,
  41         import_module("." + conf.get("rectifier", "lookaside"), __package__),
  42     )
  43     qry.init(conf)
  44     proto_needanswer = dict(common.exposed_protos())
  45     # Is this https://github.com/zeromq/pyzmq/issues/1627 still not fixed?!
  46     zctx = zmq.Context()  # type: ignore
  47     zsub = zctx.socket(zmq.SUB)  # type: ignore
  48     zsub.connect(conf.get("collector", "publishurl"))
  49     for proto in proto_needanswer.keys():
  50         zsub.setsockopt(zmq.SUBSCRIBE, topic(proto))
  51     zpush = zctx.socket(zmq.PUSH)  # type: ignore
  52     zpush.connect(conf.get("collector", "listenurl"))
  53     zpub = zctx.socket(zmq.PUB)  # type: ignore
  54     oldmask = umask(0o117)
  55     zpub.bind(conf.get("rectifier", "publishurl"))
  56     umask(oldmask)
  57
  58     try:
  59         while True:
  60             zmsg = Bcast(zsub.recv())
  61             msg = common.parse_message(
  62                 zmsg.proto, zmsg.packet, is_incoming=zmsg.is_incoming
  63             )
  64             log.debug(
  65                 "IMEI %s from %s at %s: %s",
  66                 zmsg.imei,
  67                 zmsg.peeraddr,
  68                 datetime.fromtimestamp(zmsg.when).astimezone(tz=timezone.utc),
  69                 msg,
  70             )
  71             rect: Report = msg.rectified()
  72             log.debug("rectified: %s", rect)
  73             if isinstance(rect, (CoordReport, StatusReport)):
  74                 zpub.send(Rept(imei=zmsg.imei, payload=rect.json).packed)
  75             elif isinstance(rect, HintReport):
  76                 try:
  77                     lat, lon = qry.lookup(
  78                         rect.mcc,
  79                         rect.mnc,
  80                         rect.gsm_cells,
  81                         list((mac, strng) for _, mac, strng in rect.wifi_aps),
  82                     )
  83                     log.debug(
  84                         "Approximated lat=%s, lon=%s for %s", lat, lon, rect
  85                     )
  86                     if proto_needanswer.get(zmsg.proto, False):
  87                         resp = Resp(
  88                             imei=zmsg.imei,
  89                             when=zmsg.when,  # not the current time, but the original!
  90                             packet=msg.Out(latitude=lat, longitude=lon).packed,
  91                         )
  92                         log.debug("Sending reponse %s", resp)
  93                         zpush.send(resp.packed)
  94                     rept = CoordReport(
  95                         devtime=rect.devtime,
  96                         battery_percentage=rect.battery_percentage,
  97                         accuracy=None,
  98                         altitude=None,
  99                         speed=None,
 100                         direction=None,
 101                         latitude=lat,
 102                         longitude=lon,
 103                     )
 104                     log.debug("Sending report %s", rept)
 105                     zpub.send(
 106                         Rept(
 107                             imei=zmsg.imei,
 108                             payload=rept.json,
 109                         ).packed
 110                     )
 111                 except Exception as e:
 112                     log.exception(
 113                         "Lookup for %s rectified as %s resulted in %s",
 114                         msg,
 115                         rect,
 116                         e,
 117                     )
 118
 119     except KeyboardInterrupt:
 120         zsub.close()
 121         zpub.close()
 122         zpush.close()
 123         zctx.destroy()  # type: ignore
 124         qry.shut()
 125
 126
 127 if __name__.endswith("__main__"):
 128     runserver(common.init(log))