Added active_scan mode to bluetooth.scanner backend to actively perform a lookup name on each device discovered at least once [see #174]

This commit is contained in:
Fabio Manganiello 2021-03-09 11:50:40 +01:00
parent 7687e52058
commit 4902475caf
2 changed files with 77 additions and 9 deletions

View file

@ -1,6 +1,9 @@
import time
from threading import Thread, RLock
from typing import Dict, Optional
from platypush.backend.sensor import SensorBackend
from platypush.context import get_plugin
from platypush.message.event.bluetooth import BluetoothDeviceFoundEvent, BluetoothDeviceLostEvent
@ -20,10 +23,13 @@ class BluetoothScannerBackend(SensorBackend):
"""
def __init__(self, device_id: Optional[int] = None, scan_duration: int = 10, **kwargs):
def __init__(self, device_id: Optional[int] = None, scan_duration: int = 10, active_scan: bool = False, **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
``.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,
@ -31,17 +37,79 @@ 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.scan_duration = scan_duration
def _add_last_seen_device(self, dev):
addr = dev.pop('addr')
if addr not in self._last_seen_devices:
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:
return
self.bus.post(BluetoothDeviceLostEvent(address=addr, **dev))
del self._last_seen_devices[addr]
def _addr_tracker(self, addr):
with self._bt_lock:
name = get_plugin('bluetooth').lookup_name(addr, timeout=self.scan_duration)
if name is None:
self._remove_last_seen_device(addr)
else:
self._add_last_seen_device({'addr': addr, 'name': name})
def _bt_tracker(self):
self.logger.info('Starting Bluetooth tracker')
while not self.should_stop():
trackers = []
for addr in self._devices_to_track:
tracker = Thread(target=self._addr_tracker, args=(addr,))
tracker.start()
trackers.append(tracker)
for tracker in trackers:
tracker.join(timeout=self.scan_duration)
time.sleep(self.scan_duration)
self.logger.info('Bluetooth tracker stopped')
def get_measurement(self):
with self._bt_lock:
return super().get_measurement()
def process_data(self, data: Dict[str, dict], new_data: Dict[str, dict]):
for addr, dev in data.items():
if addr not in self._last_seen_devices:
self.bus.post(BluetoothDeviceFoundEvent(address=dev.pop('addr'), **dev))
self._last_seen_devices[addr] = {'addr': addr, **dev}
self._add_last_seen_device(dev)
for addr, dev in self._last_seen_devices.copy().items():
if addr not in data:
self.bus.post(BluetoothDeviceLostEvent(address=dev.pop('addr'), **dev))
del self._last_seen_devices[addr]
if not self.active_scan:
for addr, dev in self._last_seen_devices.copy().items():
if addr not in data:
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):
super().on_stop()
if self._tracking_thread and self._tracking_thread.is_alive():
self.logger.info('Waiting for the Bluetooth tracking thread to stop')
self._tracking_thread.join(timeout=self.scan_duration)
# vim:sw=4:ts=4:et:

View file

@ -118,7 +118,7 @@ class BluetoothPlugin(SensorPlugin):
"""
from bluetooth import lookup_name
self.logger.info('Looking up name for device {}'.format(addr))
self.logger.debug('Looking up name for device {}'.format(addr))
name = lookup_name(addr, timeout=timeout)
dev = {