core/homeassistant/components/bluetooth/scanner.py

381 lines
14 KiB
Python

"""The bluetooth integration."""
from __future__ import annotations
import asyncio
from collections.abc import Callable
from datetime import datetime
import logging
import platform
import time
import async_timeout
import bleak
from bleak import BleakError
from bleak.backends.device import BLEDevice
from bleak.backends.scanner import AdvertisementData
from dbus_next import InvalidMessageError
from homeassistant.const import EVENT_HOMEASSISTANT_STOP
from homeassistant.core import (
CALLBACK_TYPE,
Event,
HomeAssistant,
callback as hass_callback,
)
from homeassistant.exceptions import HomeAssistantError
from homeassistant.helpers.event import async_track_time_interval
from homeassistant.util.package import is_docker_env
from .const import (
SCANNER_WATCHDOG_INTERVAL,
SCANNER_WATCHDOG_TIMEOUT,
SOURCE_LOCAL,
START_TIMEOUT,
)
from .models import BaseHaScanner, BluetoothScanningMode, BluetoothServiceInfoBleak
from .util import adapter_human_name, async_reset_adapter
OriginalBleakScanner = bleak.BleakScanner
MONOTONIC_TIME = time.monotonic
_LOGGER = logging.getLogger(__name__)
MONOTONIC_TIME = time.monotonic
# If the adapter is in a stuck state the following errors are raised:
NEED_RESET_ERRORS = [
"org.bluez.Error.Failed",
"org.bluez.Error.InProgress",
"org.bluez.Error.NotReady",
]
# When the adapter is still initializing, the scanner will raise an exception
# with org.freedesktop.DBus.Error.UnknownObject
WAIT_FOR_ADAPTER_TO_INIT_ERRORS = ["org.freedesktop.DBus.Error.UnknownObject"]
ADAPTER_INIT_TIME = 1.5
START_ATTEMPTS = 3
SCANNING_MODE_TO_BLEAK = {
BluetoothScanningMode.ACTIVE: "active",
BluetoothScanningMode.PASSIVE: "passive",
}
# The minimum number of seconds to know
# the adapter has not had advertisements
# and we already tried to restart the scanner
# without success when the first time the watch
# dog hit the failure path.
SCANNER_WATCHDOG_MULTIPLE = (
SCANNER_WATCHDOG_TIMEOUT + SCANNER_WATCHDOG_INTERVAL.total_seconds()
)
class ScannerStartError(HomeAssistantError):
"""Error to indicate that the scanner failed to start."""
def create_bleak_scanner(
scanning_mode: BluetoothScanningMode, adapter: str | None
) -> bleak.BleakScanner:
"""Create a Bleak scanner."""
scanner_kwargs = {"scanning_mode": SCANNING_MODE_TO_BLEAK[scanning_mode]}
# Only Linux supports multiple adapters
if adapter and platform.system() == "Linux":
scanner_kwargs["adapter"] = adapter
_LOGGER.debug("Initializing bluetooth scanner with %s", scanner_kwargs)
try:
return OriginalBleakScanner(**scanner_kwargs) # type: ignore[arg-type]
except (FileNotFoundError, BleakError) as ex:
raise RuntimeError(f"Failed to initialize Bluetooth: {ex}") from ex
class HaScanner(BaseHaScanner):
"""Operate and automatically recover a BleakScanner.
Multiple BleakScanner can be used at the same time
if there are multiple adapters. This is only useful
if the adapters are not located physically next to each other.
Example use cases are usbip, a long extension cable, usb to bluetooth
over ethernet, usb over ethernet, etc.
"""
def __init__(
self,
hass: HomeAssistant,
scanner: bleak.BleakScanner,
adapter: str,
address: str,
) -> None:
"""Init bluetooth discovery."""
self.hass = hass
self.scanner = scanner
self.adapter = adapter
self._start_stop_lock = asyncio.Lock()
self._cancel_stop: CALLBACK_TYPE | None = None
self._cancel_watchdog: CALLBACK_TYPE | None = None
self._last_detection = 0.0
self._start_time = 0.0
self._callbacks: list[Callable[[BluetoothServiceInfoBleak], None]] = []
self.name = adapter_human_name(adapter, address)
self.source = self.adapter or SOURCE_LOCAL
@property
def discovered_devices(self) -> list[BLEDevice]:
"""Return a list of discovered devices."""
return self.scanner.discovered_devices
@hass_callback
def async_register_callback(
self, callback: Callable[[BluetoothServiceInfoBleak], None]
) -> CALLBACK_TYPE:
"""Register a callback.
Currently this is used to feed the callbacks into the
central manager.
"""
def _remove() -> None:
self._callbacks.remove(callback)
self._callbacks.append(callback)
return _remove
@hass_callback
def _async_detection_callback(
self,
device: BLEDevice,
advertisement_data: AdvertisementData,
) -> None:
"""Call the callback when an advertisement is received.
Currently this is used to feed the callbacks into the
central manager.
"""
callback_time = MONOTONIC_TIME()
if (
advertisement_data.local_name
or advertisement_data.manufacturer_data
or advertisement_data.service_data
or advertisement_data.service_uuids
):
# Don't count empty advertisements
# as the adapter is in a failure
# state if all the data is empty.
self._last_detection = callback_time
service_info = BluetoothServiceInfoBleak(
name=advertisement_data.local_name or device.name or device.address,
address=device.address,
rssi=device.rssi,
manufacturer_data=advertisement_data.manufacturer_data,
service_data=advertisement_data.service_data,
service_uuids=advertisement_data.service_uuids,
source=self.source,
device=device,
advertisement=advertisement_data,
connectable=True,
time=callback_time,
)
for callback in self._callbacks:
callback(service_info)
async def async_start(self) -> None:
"""Start bluetooth scanner."""
self.scanner.register_detection_callback(self._async_detection_callback)
async with self._start_stop_lock:
await self._async_start()
async def _async_start(self) -> None:
"""Start bluetooth scanner under the lock."""
for attempt in range(START_ATTEMPTS):
_LOGGER.debug(
"%s: Starting bluetooth discovery attempt: (%s/%s)",
self.name,
attempt + 1,
START_ATTEMPTS,
)
try:
async with async_timeout.timeout(START_TIMEOUT):
await self.scanner.start() # type: ignore[no-untyped-call]
except InvalidMessageError as ex:
_LOGGER.debug(
"%s: Invalid DBus message received: %s",
self.name,
ex,
exc_info=True,
)
raise ScannerStartError(
f"{self.name}: Invalid DBus message received: {ex}; "
"try restarting `dbus`"
) from ex
except BrokenPipeError as ex:
_LOGGER.debug(
"%s: DBus connection broken: %s", self.name, ex, exc_info=True
)
if is_docker_env():
raise ScannerStartError(
f"{self.name}: DBus connection broken: {ex}; try restarting "
"`bluetooth`, `dbus`, and finally the docker container"
) from ex
raise ScannerStartError(
f"{self.name}: DBus connection broken: {ex}; try restarting "
"`bluetooth` and `dbus`"
) from ex
except FileNotFoundError as ex:
_LOGGER.debug(
"%s: FileNotFoundError while starting bluetooth: %s",
self.name,
ex,
exc_info=True,
)
if is_docker_env():
raise ScannerStartError(
f"{self.name}: DBus service not found; docker config may "
"be missing `-v /run/dbus:/run/dbus:ro`: {ex}"
) from ex
raise ScannerStartError(
f"{self.name}: DBus service not found; make sure the DBus socket "
f"is available to Home Assistant: {ex}"
) from ex
except asyncio.TimeoutError as ex:
if attempt == 0:
await self._async_reset_adapter()
continue
raise ScannerStartError(
f"{self.name}: Timed out starting Bluetooth after {START_TIMEOUT} seconds"
) from ex
except BleakError as ex:
error_str = str(ex)
if attempt == 0:
if any(
needs_reset_error in error_str
for needs_reset_error in NEED_RESET_ERRORS
):
await self._async_reset_adapter()
continue
if attempt != START_ATTEMPTS - 1:
# If we are not out of retry attempts, and the
# adapter is still initializing, wait a bit and try again.
if any(
wait_error in error_str
for wait_error in WAIT_FOR_ADAPTER_TO_INIT_ERRORS
):
_LOGGER.debug(
"%s: Waiting for adapter to initialize; attempt (%s/%s)",
self.name,
attempt + 1,
START_ATTEMPTS,
)
await asyncio.sleep(ADAPTER_INIT_TIME)
continue
_LOGGER.debug(
"%s: BleakError while starting bluetooth; attempt: (%s/%s): %s",
self.name,
attempt + 1,
START_ATTEMPTS,
ex,
exc_info=True,
)
raise ScannerStartError(
f"{self.name}: Failed to start Bluetooth: {ex}"
) from ex
# Everything is fine, break out of the loop
break
self._async_setup_scanner_watchdog()
self._cancel_stop = self.hass.bus.async_listen_once(
EVENT_HOMEASSISTANT_STOP, self._async_hass_stopping
)
@hass_callback
def _async_setup_scanner_watchdog(self) -> None:
"""If Dbus gets restarted or updated, we need to restart the scanner."""
self._start_time = self._last_detection = MONOTONIC_TIME()
if not self._cancel_watchdog:
self._cancel_watchdog = async_track_time_interval(
self.hass, self._async_scanner_watchdog, SCANNER_WATCHDOG_INTERVAL
)
async def _async_scanner_watchdog(self, now: datetime) -> None:
"""Check if the scanner is running."""
time_since_last_detection = MONOTONIC_TIME() - self._last_detection
_LOGGER.debug(
"%s: Scanner watchdog time_since_last_detection: %s",
self.name,
time_since_last_detection,
)
if time_since_last_detection < SCANNER_WATCHDOG_TIMEOUT:
return
_LOGGER.info(
"%s: Bluetooth scanner has gone quiet for %ss, restarting",
self.name,
SCANNER_WATCHDOG_TIMEOUT,
)
async with self._start_stop_lock:
# Stop the scanner but not the watchdog
# since we want to try again later if it's still quiet
await self._async_stop_scanner()
# If there have not been any valid advertisements,
# or the watchdog has hit the failure path multiple times,
# do the reset.
if (
self._start_time == self._last_detection
or time_since_last_detection > SCANNER_WATCHDOG_MULTIPLE
):
await self._async_reset_adapter()
try:
await self._async_start()
except ScannerStartError as ex:
_LOGGER.error(
"%s: Failed to restart Bluetooth scanner: %s",
self.name,
ex,
exc_info=True,
)
async def _async_hass_stopping(self, event: Event) -> None:
"""Stop the Bluetooth integration at shutdown."""
self._cancel_stop = None
await self.async_stop()
async def _async_reset_adapter(self) -> None:
"""Reset the adapter."""
# There is currently nothing the user can do to fix this
# so we log at debug level. If we later come up with a repair
# strategy, we will change this to raise a repair issue as well.
_LOGGER.debug("%s: adapter stopped responding; executing reset", self.name)
result = await async_reset_adapter(self.adapter)
_LOGGER.debug("%s: adapter reset result: %s", self.name, result)
async def async_stop(self) -> None:
"""Stop bluetooth scanner."""
async with self._start_stop_lock:
await self._async_stop()
async def _async_stop(self) -> None:
"""Cancel watchdog and bluetooth discovery under the lock."""
if self._cancel_watchdog:
self._cancel_watchdog()
self._cancel_watchdog = None
await self._async_stop_scanner()
async def _async_stop_scanner(self) -> None:
"""Stop bluetooth discovery under the lock."""
if self._cancel_stop:
self._cancel_stop()
self._cancel_stop = None
_LOGGER.debug("%s: Stopping bluetooth discovery", self.name)
try:
await self.scanner.stop() # type: ignore[no-untyped-call]
except BleakError as ex:
# This is not fatal, and they may want to reload
# the config entry to restart the scanner if they
# change the bluetooth dongle.
_LOGGER.error("%s: Error stopping scanner: %s", self.name, ex)