several fixups (#250)

* when wifi is disconnected, stop emitting gps positions
 * fix up the requirements.txt to pull in my doctored version of the obd librarys
 * stop deleting OBD keys under any circumstances

lemon_pi/car/meringue_comms_car.py

@@ -4,16 +4,18 @@
 
 import grpc
 
+from lemon_pi.car.event_defs import WifiConnectedEvent, WifiDisconnectedEvent
 from lemon_pi.car.radio_interface import RadioInterface
 from lemon_pi.shared.data_provider_interface import GpsProvider
+from lemon_pi.shared.events import EventHandler
 from lemon_pi.shared.meringue_comms import MeringueComms, build_auth_header
 from lemon_pi_pb2 import CarNumber, ToCarMessage, ToPitMessage
 from lemon_pi_pb2_grpc import CommsServiceStub
 
 logger = logging.getLogger(__name__)
 
 
-class MeringueCommsCar(Thread, MeringueComms):
+class MeringueCommsCar(Thread, MeringueComms, EventHandler):
 
     def __init__(self, car_number: str, key: str, ping_frequency: int):
         Thread.__init__(self)
@@ -24,6 +26,9 @@ def __init__(self, car_number: str, key: str, ping_frequency: int):
         self.radio_interface = None
         self.stopped: bool = False
         self.gps_provider = None
+        self.wifi_working = False
+        WifiConnectedEvent.register_handler(self)
+        WifiDisconnectedEvent.register_handler(self)
 
     def set_radio_interface(self, radio_interface: RadioInterface):
         self.radio_interface = radio_interface
@@ -38,7 +43,9 @@ def pinger(self):
                 position = self.gps_provider.get_gps_position()
                 if position:
                     msg.ping.gps.CopyFrom(position)
-                self.send_message_from_car(msg)
+                # do not emit these if wifi is not connected
+                if self.wifi_working:
+                    self.send_message_from_car(msg)
             except grpc.RpcError:
                 pass
             sleep(self.ping_frequency)
@@ -69,3 +76,12 @@ def run(self):
                 else:
                     logger.exception("unknown error")
                     sleep(10)
+
+    def handle_event(self, event, **kwargs):
+        if event == WifiConnectedEvent:
+            self.wifi_working = True
+            return
+
+        if event == WifiDisconnectedEvent:
+            self.wifi_working = False
+            return

lemon_pi/car/obd_reader.py

@@ -77,9 +77,10 @@ def run(self) -> None:
                                     keys_to_delete.append(cmd)
                                 time.sleep(10)
                     time.sleep(0.5)
-                    for dead_key in keys_to_delete:
-                        del ObdReader.refresh_rate[dead_key]
-                        logger.info(f"removed {dead_key}")
+                    # leaving this functionality out for now, seems fragile and harmful
+                    # for dead_key in keys_to_delete:
+                    #     del ObdReader.refresh_rate[dead_key]
+                    #     logger.info(f"removed {dead_key}")
 
             except Exception as e:
                 logger.exception("bad stuff in OBD land %s", e)
@@ -90,6 +91,9 @@ def run(self) -> None:
                 time.sleep(10)
 
     def connect(self, old_connection):
+        if not UsbDetector.detected(UsbDevice.OBD):
+            return None
+
         port = UsbDetector.get(UsbDevice.OBD)
         if not port:
             return None

requirements.txt

@@ -8,7 +8,7 @@ grpcio-tools==1.40.0
 guizero>=1.3.0
 haversine>=2.3.0
 numpy>=1.21
-obd==0.7.1
+git+https://github.com/sprintf/python-OBD@master
 Pillow>=8.1.1
 Pint==0.7.2
 protobuf==3.16.0