Add googlemaps lookaside backend

[loctrkd.git] / gps303 / lookaside.py

diff --git a/gps303/lookaside.py b/gps303/lookaside.py
index 60dcea73f54b5ad1fe52128976b8d532cce95203..7655f55e4bb095655b41d525aba89cf0a4b12c87 100644 (file)
--- a/gps303/lookaside.py
+++ b/gps303/lookaside.py
@@ -1,34 +1,26 @@
 """ Estimate coordinates from WIFI_POSITIONING and send back """
 
 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, proto_by_name, WIFI_POSITIONING
-from .opencellid import qry_cell
-from .zmsg import Bcast, LocEvt, Resp
+from .gps303proto import parse_message, WIFI_POSITIONING
+from .zmsg import Bcast, Resp, topic
 
 log = getLogger("gps303/lookaside")
 
 
 def runserver(conf):
+    qry = import_module("." + conf.get("lookaside", "backend"), __package__)
+    qry.init(conf)
     zctx = zmq.Context()
-    zpub = zctx.socket(zmq.PUB)
-    oldmask = umask(0o117)
-    zpub.bind(conf.get("lookaside", "publishurl"))
-    umask(oldmask)
     zsub = zctx.socket(zmq.SUB)
     zsub.connect(conf.get("collector", "publishurl"))
-    for protoname in (
-        "GPS_POSITIONING",
-        "GPS_OFFLINE_POSITIONING",
-        "WIFI_POSITIONING",
-    ):
-        topic = pack("B", proto_by_name(protoname))
-        zsub.setsockopt(zmq.SUBSCRIBE, topic)
+    zsub.setsockopt(zmq.SUBSCRIBE, topic(WIFI_POSITIONING.PROTO))
     zpush = zctx.socket(zmq.PUSH)
     zpush.connect(conf.get("collector", "listenurl"))
 
@@ -43,29 +35,17 @@ def runserver(conf):
                 datetime.fromtimestamp(zmsg.when).astimezone(tz=timezone.utc),
                 msg,
             )
-            if isinstance(msg, WIFI_POSITIONING):
-                is_gps = False
-                lat, lon = qry_cell(
-                    conf["opencellid"]["dbfn"], msg.mcc, msg.gsm_cells
-                )
+            try:
+                lat, lon = qry.lookup(msg.mcc, msg.mnc, msg.gsm_cells, msg.wifi_aps)
                 resp = Resp(
-                    imei=zmsg.imei, packet=msg.Out(lat=lat, lon=lon).packed
+                    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)
-            else:
-                is_gps = True
-                lat = msg.latitude
-                lon = msg.longitude
-            zpub.send(
-                LocEvt(
-                    imei=zmsg.imei,
-                    devtime=msg.devtime,
-                    is_gps=is_gps,
-                    lat=lat,
-                    lon=lon,
-                ).packed
-            )
+            except Exception as e:
+                log.warning("Lookup for %s resulted in %s", msg, e)
 
     except KeyboardInterrupt:
         pass