- Addressed comments in #174

- Replaced active_scan flag with a list of track_devices

platypush/backend/bluetooth/scanner/__init__.py

@@ -1,6 +1,6 @@
 import time
 from threading import Thread, RLock
-from typing import Dict, Optional
+from typing import Dict, Optional, List
 
 from platypush.backend.sensor import SensorBackend
 from platypush.context import get_plugin
@@ -23,13 +23,12 @@ class BluetoothScannerBackend(SensorBackend):
 
     """
 
-    def __init__(self, device_id: Optional[int] = None, scan_duration: int = 10, active_scan: bool = False, **kwargs):
+    def __init__(self, device_id: Optional[int] = None, scan_duration: int = 10,
+                 track_devices: Optional[List[str]] = None, **kwargs):
         """
         :param device_id: Bluetooth adapter ID to use (default configured on the ``bluetooth`` plugin if None).
         :param scan_duration:  How long the scan should run (default: 10 seconds).
-        :param active_scan: Set to True if you want to actively track the devices through a periodic
+        :param track_devices: List of addresses of devices to actively track, even if they aren't discoverable.
-            ``.lookup_name`` call. This is likely to produce a more accurate tracking, but it may negatively impact the
-            duration of devices that run on battery.
         """
         super().__init__(plugin='bluetooth', plugin_args={
             'device_id': device_id,
@@ -37,10 +36,9 @@ class BluetoothScannerBackend(SensorBackend):
         }, **kwargs)
 
         self._last_seen_devices = {}
-        self._devices_to_track = set()
         self._tracking_thread: Optional[Thread] = None
         self._bt_lock = RLock()
-        self.active_scan = active_scan
+        self.track_devices = set(track_devices or [])
         self.scan_duration = scan_duration
 
     def _add_last_seen_device(self, dev):
@@ -49,9 +47,6 @@ class BluetoothScannerBackend(SensorBackend):
             self.bus.post(BluetoothDeviceFoundEvent(address=addr, **dev))
         self._last_seen_devices[addr] = {'addr': addr, **dev}
 
-        if self.active_scan and addr not in self._devices_to_track:
-            self._devices_to_track.add(addr)
-
     def _remove_last_seen_device(self, addr: str):
         dev = self._last_seen_devices.get(addr)
         if not dev:
@@ -62,7 +57,7 @@ class BluetoothScannerBackend(SensorBackend):
 
     def _addr_tracker(self, addr):
         with self._bt_lock:
-            name = get_plugin('bluetooth').lookup_name(addr, timeout=self.scan_duration)
+            name = get_plugin('bluetooth').lookup_name(addr, timeout=self.scan_duration).name
 
         if name is None:
             self._remove_last_seen_device(addr)
@@ -73,7 +68,7 @@ class BluetoothScannerBackend(SensorBackend):
         self.logger.info('Starting Bluetooth tracker')
         while not self.should_stop():
             trackers = []
-            for addr in self._devices_to_track:
+            for addr in self.track_devices:
                 tracker = Thread(target=self._addr_tracker, args=(addr,))
                 tracker.start()
                 trackers.append(tracker)
@@ -93,16 +88,13 @@ class BluetoothScannerBackend(SensorBackend):
         for addr, dev in data.items():
             self._add_last_seen_device(dev)
 
-        if not self.active_scan:
         for addr, dev in self._last_seen_devices.copy().items():
-                if addr not in data:
+            if addr not in data and addr not in self.track_devices:
                 self._remove_last_seen_device(addr)
 
     def run(self):
-        if self.active_scan:
         self._tracking_thread = Thread(target=self._bt_tracker)
         self._tracking_thread.start()
-
         super().run()
 
     def on_stop(self):