typing: annotate lookaside.py

[loctrkd.git] / gps303 / lookaside.py

diff --git a/gps303/lookaside.py b/gps303/lookaside.py
index 3c3ee32f10f50790c28fb25d291356caa6e02b93..fb976a00acfd1a968aded27af08d72f4883faf17 100644 (file)
--- a/gps303/lookaside.py
+++ b/gps303/lookaside.py
@@ -1,13 +1,57 @@
-"""
-For when responding to the terminal is not trivial
-"""
-
-from .GT06mod import *
-from .opencellid import qry_cell
-
-def prepare_response(conf, msg):
-    if isinstance(msg, WIFI_POSITIONING):
-        lat, lon = qry_cell(conf["opencellid"]["dbfn"],
-                msg.mcc, msg.gsm_cells)
-        return {"lat": lat, "lon": lon}
-    return {}
+""" Estimate coordinates from WIFI_POSITIONING and send back """
+
+from configparser import ConfigParser
+from datetime import datetime, timezone
+from importlib import import_module
+from logging import getLogger
+from os import umask
+from struct import pack
+import zmq
+
+from . import common
+from .gps303proto import parse_message, WIFI_POSITIONING
+from .zmsg import Bcast, Resp, topic
+
+log = getLogger("gps303/lookaside")
+
+
+def runserver(conf: ConfigParser) -> None:
+    qry = import_module("." + conf.get("lookaside", "backend"), __package__)
+    qry.init(conf)
+    # Is this https://github.com/zeromq/pyzmq/issues/1627 still not fixed?!
+    zctx = zmq.Context()  # type: ignore
+    zsub = zctx.socket(zmq.SUB)  # type: ignore
+    zsub.connect(conf.get("collector", "publishurl"))
+    zsub.setsockopt(zmq.SUBSCRIBE, topic(WIFI_POSITIONING.PROTO))
+    zpush = zctx.socket(zmq.PUSH)  # type: ignore
+    zpush.connect(conf.get("collector", "listenurl"))
+
+    try:
+        while True:
+            zmsg = Bcast(zsub.recv())
+            msg = parse_message(zmsg.packet)
+            log.debug(
+                "IMEI %s from %s at %s: %s",
+                zmsg.imei,
+                zmsg.peeraddr,
+                datetime.fromtimestamp(zmsg.when).astimezone(tz=timezone.utc),
+                msg,
+            )
+            try:
+                lat, lon = qry.lookup(msg.mcc, msg.mnc, msg.gsm_cells, msg.wifi_aps)
+                resp = Resp(
+                    imei=zmsg.imei,
+                    when=zmsg.when,  # not the current time, but the original!
+                    packet=msg.Out(latitude=lat, longitude=lon).packed,
+                )
+                log.debug("Response for lat=%s, lon=%s: %s", lat, lon, resp)
+                zpush.send(resp.packed)
+            except Exception as e:
+                log.warning("Lookup for %s resulted in %s", msg, e)
+
+    except KeyboardInterrupt:
+        pass
+
+
+if __name__.endswith("__main__"):
+    runserver(common.init(log))