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 import zmq
  10
  11 from . import common
  12 from .zmsg import Bcast, Report, Resp, topic
  13
  14 log = getLogger("loctrkd/rectifier")
  15
  16
  17 def runserver(conf: ConfigParser) -> None:
  18     qry = import_module("." + conf.get("rectifier", "lookaside"), __package__)
  19     qry.init(conf)
  20     proto_needanswer = dict(common.exposed_protos())
  21     # Is this https://github.com/zeromq/pyzmq/issues/1627 still not fixed?!
  22     zctx = zmq.Context()  # type: ignore
  23     zsub = zctx.socket(zmq.SUB)  # type: ignore
  24     zsub.connect(conf.get("collector", "publishurl"))
  25     for proto in proto_needanswer.keys():
  26         zsub.setsockopt(zmq.SUBSCRIBE, topic(proto))
  27     zpush = zctx.socket(zmq.PUSH)  # type: ignore
  28     zpush.connect(conf.get("collector", "listenurl"))
  29     zpub = zctx.socket(zmq.PUB)  # type: ignore
  30     zpub.connect(conf.get("rectifier", "publishurl"))
  31
  32     try:
  33         while True:
  34             zmsg = Bcast(zsub.recv())
  35             msg = common.parse_message(
  36                 zmsg.proto, zmsg.packet, is_incoming=zmsg.is_incoming
  37             )
  38             log.debug(
  39                 "IMEI %s from %s at %s: %s",
  40                 zmsg.imei,
  41                 zmsg.peeraddr,
  42                 datetime.fromtimestamp(zmsg.when).astimezone(tz=timezone.utc),
  43                 msg,
  44             )
  45             rect = msg.rectified()
  46             log.debug("rectified: %s", rect)
  47             if rect.type == "approximate_location":
  48                 try:
  49                     lat, lon = qry.lookup(
  50                         rect.mcc, rect.mnc, rect.base_stations, rect.wifi_aps
  51                     )
  52                     resp = Resp(
  53                         imei=zmsg.imei,
  54                         when=zmsg.when,  # not the current time, but the original!
  55                         packet=msg.Out(latitude=lat, longitude=lon).packed,
  56                     )
  57                     log.debug(
  58                         "Response for lat=%s, lon=%s: %s", lat, lon, resp
  59                     )
  60                     zpush.send(resp.packed)
  61                 except Exception as e:
  62                     log.warning("Lookup for %s resulted in %s", msg, e)
  63
  64     except KeyboardInterrupt:
  65         zsub.close()
  66         zpub.close()
  67         zpush.close()
  68         zctx.destroy()  # type: ignore
  69         qry.shut()
  70
  71
  72 if __name__.endswith("__main__"):
  73     runserver(common.init(log))