core/homeassistant/components/esphome/bluetooth/client.py

655 lines
26 KiB
Python

"""Bluetooth client for esphome."""
from __future__ import annotations
import asyncio
from collections.abc import Callable, Coroutine
import contextlib
import logging
from typing import Any, TypeVar, cast
import uuid
from aioesphomeapi import (
ESP_CONNECTION_ERROR_DESCRIPTION,
ESPHOME_GATT_ERRORS,
BLEConnectionError,
)
from aioesphomeapi.connection import APIConnectionError, TimeoutAPIError
from aioesphomeapi.core import BluetoothGATTAPIError
import async_timeout
from bleak.backends.characteristic import BleakGATTCharacteristic
from bleak.backends.client import BaseBleakClient, NotifyCallback
from bleak.backends.device import BLEDevice
from bleak.backends.service import BleakGATTServiceCollection
from bleak.exc import BleakError
from homeassistant.components.bluetooth import async_scanner_by_source
from homeassistant.core import CALLBACK_TYPE, HomeAssistant
from ..domain_data import DomainData
from .characteristic import BleakGATTCharacteristicESPHome
from .descriptor import BleakGATTDescriptorESPHome
from .service import BleakGATTServiceESPHome
DEFAULT_MTU = 23
GATT_HEADER_SIZE = 3
DISCONNECT_TIMEOUT = 5.0
CONNECT_FREE_SLOT_TIMEOUT = 2.0
GATT_READ_TIMEOUT = 30.0
# CCCD (Characteristic Client Config Descriptor)
CCCD_UUID = "00002902-0000-1000-8000-00805f9b34fb"
CCCD_NOTIFY_BYTES = b"\x01\x00"
CCCD_INDICATE_BYTES = b"\x02\x00"
MIN_BLUETOOTH_PROXY_VERSION_HAS_CACHE = 3
DEFAULT_MAX_WRITE_WITHOUT_RESPONSE = DEFAULT_MTU - GATT_HEADER_SIZE
_LOGGER = logging.getLogger(__name__)
_WrapFuncType = TypeVar( # pylint: disable=invalid-name
"_WrapFuncType", bound=Callable[..., Any]
)
def mac_to_int(address: str) -> int:
"""Convert a mac address to an integer."""
return int(address.replace(":", ""), 16)
def verify_connected(func: _WrapFuncType) -> _WrapFuncType:
"""Define a wrapper throw BleakError if not connected."""
async def _async_wrap_bluetooth_connected_operation(
self: "ESPHomeClient", *args: Any, **kwargs: Any
) -> Any:
disconnected_event = (
self._disconnected_event # pylint: disable=protected-access
)
if not disconnected_event:
raise BleakError("Not connected")
task = asyncio.create_task(func(self, *args, **kwargs))
done, _ = await asyncio.wait(
(task, disconnected_event.wait()),
return_when=asyncio.FIRST_COMPLETED,
)
if disconnected_event.is_set():
task.cancel()
with contextlib.suppress(asyncio.CancelledError):
await task
raise BleakError(
f"{self._source}: {self._ble_device.name} - {self._ble_device.address}: " # pylint: disable=protected-access
"Disconnected during operation"
)
return next(iter(done)).result()
return cast(_WrapFuncType, _async_wrap_bluetooth_connected_operation)
def api_error_as_bleak_error(func: _WrapFuncType) -> _WrapFuncType:
"""Define a wrapper throw esphome api errors as BleakErrors."""
async def _async_wrap_bluetooth_operation(
self: "ESPHomeClient", *args: Any, **kwargs: Any
) -> Any:
try:
return await func(self, *args, **kwargs)
except TimeoutAPIError as err:
raise asyncio.TimeoutError(str(err)) from err
except BluetoothGATTAPIError as ex:
# If the device disconnects in the middle of an operation
# be sure to mark it as disconnected so any library using
# the proxy knows to reconnect.
#
# Because callbacks are delivered asynchronously it's possible
# that we find out about the disconnection during the operation
# before the callback is delivered.
# pylint: disable=protected-access
if ex.error.error == -1:
_LOGGER.debug(
"%s: %s - %s: BLE device disconnected during %s operation",
self._source,
self._ble_device.name,
self._ble_device.address,
func.__name__,
)
self._async_ble_device_disconnected()
raise BleakError(str(ex)) from ex
except APIConnectionError as err:
raise BleakError(str(err)) from err
return cast(_WrapFuncType, _async_wrap_bluetooth_operation)
class ESPHomeClient(BaseBleakClient):
"""ESPHome Bleak Client."""
def __init__(
self, address_or_ble_device: BLEDevice | str, *args: Any, **kwargs: Any
) -> None:
"""Initialize the ESPHomeClient."""
assert isinstance(address_or_ble_device, BLEDevice)
super().__init__(address_or_ble_device, *args, **kwargs)
self._hass: HomeAssistant = kwargs["hass"]
self._ble_device = address_or_ble_device
self._address_as_int = mac_to_int(self._ble_device.address)
assert self._ble_device.details is not None
self._source = self._ble_device.details["source"]
self.domain_data = DomainData.get(self._hass)
config_entry = self.domain_data.get_by_unique_id(self._source)
self.entry_data = self.domain_data.get_entry_data(config_entry)
self._client = self.entry_data.client
self._is_connected = False
self._mtu: int | None = None
self._cancel_connection_state: CALLBACK_TYPE | None = None
self._notify_cancels: dict[
int, tuple[Callable[[], Coroutine[Any, Any, None]], Callable[[], None]]
] = {}
self._disconnected_event: asyncio.Event | None = None
device_info = self.entry_data.device_info
assert device_info is not None
self._connection_version = device_info.bluetooth_proxy_version
self._address_type = address_or_ble_device.details["address_type"]
def __str__(self) -> str:
"""Return the string representation of the client."""
return f"ESPHomeClient ({self.address})"
def _unsubscribe_connection_state(self) -> None:
"""Unsubscribe from connection state updates."""
if not self._cancel_connection_state:
return
try:
self._cancel_connection_state()
except (AssertionError, ValueError) as ex:
_LOGGER.debug(
"%s: %s - %s: Failed to unsubscribe from connection state (likely connection dropped): %s",
self._source,
self._ble_device.name,
self._ble_device.address,
ex,
)
self._cancel_connection_state = None
def _async_disconnected_cleanup(self) -> None:
"""Clean up on disconnect."""
self.services = BleakGATTServiceCollection() # type: ignore[no-untyped-call]
self._is_connected = False
for _, notify_abort in self._notify_cancels.values():
notify_abort()
self._notify_cancels.clear()
if self._disconnected_event:
self._disconnected_event.set()
self._disconnected_event = None
self._unsubscribe_connection_state()
def _async_ble_device_disconnected(self) -> None:
"""Handle the BLE device disconnecting from the ESP."""
was_connected = self._is_connected
self._async_disconnected_cleanup()
if was_connected:
_LOGGER.debug(
"%s: %s - %s: BLE device disconnected",
self._source,
self._ble_device.name,
self._ble_device.address,
)
self._async_call_bleak_disconnected_callback()
def _async_esp_disconnected(self) -> None:
"""Handle the esp32 client disconnecting from hass."""
_LOGGER.debug(
"%s: %s - %s: ESP device disconnected",
self._source,
self._ble_device.name,
self._ble_device.address,
)
self.entry_data.disconnect_callbacks.remove(self._async_esp_disconnected)
self._async_ble_device_disconnected()
def _async_call_bleak_disconnected_callback(self) -> None:
"""Call the disconnected callback to inform the bleak consumer."""
if self._disconnected_callback:
self._disconnected_callback(self)
self._disconnected_callback = None
@api_error_as_bleak_error
async def connect(
self, dangerous_use_bleak_cache: bool = False, **kwargs: Any
) -> bool:
"""Connect to a specified Peripheral.
Keyword Args:
timeout (float): Timeout for required ``BleakScanner.find_device_by_address`` call. Defaults to 10.0.
Returns:
Boolean representing connection status.
"""
await self._wait_for_free_connection_slot(CONNECT_FREE_SLOT_TIMEOUT)
entry_data = self.entry_data
self._mtu = entry_data.get_gatt_mtu_cache(self._address_as_int)
has_cache = bool(
dangerous_use_bleak_cache
and self._connection_version >= MIN_BLUETOOTH_PROXY_VERSION_HAS_CACHE
and entry_data.get_gatt_services_cache(self._address_as_int)
and self._mtu
)
connected_future: asyncio.Future[bool] = asyncio.Future()
def _on_bluetooth_connection_state(
connected: bool, mtu: int, error: int
) -> None:
"""Handle a connect or disconnect."""
_LOGGER.debug(
"%s: %s - %s: Connection state changed to connected=%s mtu=%s error=%s",
self._source,
self._ble_device.name,
self._ble_device.address,
connected,
mtu,
error,
)
if connected:
self._is_connected = True
if not self._mtu:
self._mtu = mtu
entry_data.set_gatt_mtu_cache(self._address_as_int, mtu)
else:
self._async_ble_device_disconnected()
if connected_future.done():
return
if error:
try:
ble_connection_error = BLEConnectionError(error)
ble_connection_error_name = ble_connection_error.name
human_error = ESP_CONNECTION_ERROR_DESCRIPTION[ble_connection_error]
except (KeyError, ValueError):
ble_connection_error_name = str(error)
human_error = ESPHOME_GATT_ERRORS.get(
error, f"Unknown error code {error}"
)
connected_future.set_exception(
BleakError(
f"Error {ble_connection_error_name} while connecting: {human_error}"
)
)
return
if not connected:
connected_future.set_exception(BleakError("Disconnected"))
return
_LOGGER.debug(
"%s: %s - %s: connected, registering for disconnected callbacks",
self._source,
self._ble_device.name,
self._ble_device.address,
)
entry_data.disconnect_callbacks.append(self._async_esp_disconnected)
connected_future.set_result(connected)
timeout = kwargs.get("timeout", self._timeout)
if not (scanner := async_scanner_by_source(self._hass, self._source)):
raise BleakError("Scanner disappeared for {self._source}")
with scanner.connecting():
try:
self._cancel_connection_state = (
await self._client.bluetooth_device_connect(
self._address_as_int,
_on_bluetooth_connection_state,
timeout=timeout,
has_cache=has_cache,
version=self._connection_version,
address_type=self._address_type,
)
)
except Exception:
with contextlib.suppress(BleakError):
# If the connect call throws an exception,
# we need to make sure we await the future
# to avoid a warning about an un-retrieved
# exception since we prefer to raise the
# exception from the connect call as it
# will be more descriptive.
if connected_future.done():
await connected_future
connected_future.cancel()
raise
await connected_future
try:
await self.get_services(dangerous_use_bleak_cache=dangerous_use_bleak_cache)
except asyncio.CancelledError:
# On cancel we must still raise cancelled error
# to avoid blocking the cancellation even if the
# disconnect call fails.
with contextlib.suppress(Exception):
await self.disconnect()
raise
except Exception:
await self.disconnect()
raise
self._disconnected_event = asyncio.Event()
return True
@api_error_as_bleak_error
async def disconnect(self) -> bool:
"""Disconnect from the peripheral device."""
self._async_disconnected_cleanup()
await self._client.bluetooth_device_disconnect(self._address_as_int)
await self._wait_for_free_connection_slot(DISCONNECT_TIMEOUT)
return True
async def _wait_for_free_connection_slot(self, timeout: float) -> None:
"""Wait for a free connection slot."""
if self.entry_data.ble_connections_free:
return
_LOGGER.debug(
"%s: %s - %s: Out of connection slots, waiting for a free one",
self._source,
self._ble_device.name,
self._ble_device.address,
)
async with async_timeout.timeout(timeout):
await self.entry_data.wait_for_ble_connections_free()
@property
def is_connected(self) -> bool:
"""Is Connected."""
return self._is_connected
@property
def mtu_size(self) -> int:
"""Get ATT MTU size for active connection."""
return self._mtu or DEFAULT_MTU
@verify_connected
@api_error_as_bleak_error
async def pair(self, *args: Any, **kwargs: Any) -> bool:
"""Attempt to pair."""
raise NotImplementedError("Pairing is not available in ESPHome.")
@verify_connected
@api_error_as_bleak_error
async def unpair(self) -> bool:
"""Attempt to unpair."""
raise NotImplementedError("Pairing is not available in ESPHome.")
@api_error_as_bleak_error
async def get_services(
self, dangerous_use_bleak_cache: bool = False, **kwargs: Any
) -> BleakGATTServiceCollection:
"""Get all services registered for this GATT server.
Returns:
A :py:class:`bleak.backends.service.BleakGATTServiceCollection` with this device's services tree.
"""
address_as_int = self._address_as_int
entry_data = self.entry_data
# If the connection version >= 3, we must use the cache
# because the esp has already wiped the services list to
# save memory.
if (
self._connection_version >= MIN_BLUETOOTH_PROXY_VERSION_HAS_CACHE
or dangerous_use_bleak_cache
) and (cached_services := entry_data.get_gatt_services_cache(address_as_int)):
_LOGGER.debug(
"%s: %s - %s: Cached services hit",
self._source,
self._ble_device.name,
self._ble_device.address,
)
self.services = cached_services
return self.services
_LOGGER.debug(
"%s: %s - %s: Cached services miss",
self._source,
self._ble_device.name,
self._ble_device.address,
)
esphome_services = await self._client.bluetooth_gatt_get_services(
address_as_int
)
_LOGGER.debug(
"%s: %s - %s: Got services: %s",
self._source,
self._ble_device.name,
self._ble_device.address,
esphome_services,
)
max_write_without_response = self.mtu_size - GATT_HEADER_SIZE
services = BleakGATTServiceCollection() # type: ignore[no-untyped-call]
for service in esphome_services.services:
services.add_service(BleakGATTServiceESPHome(service))
for characteristic in service.characteristics:
services.add_characteristic(
BleakGATTCharacteristicESPHome(
characteristic,
max_write_without_response,
service.uuid,
service.handle,
)
)
for descriptor in characteristic.descriptors:
services.add_descriptor(
BleakGATTDescriptorESPHome(
descriptor,
characteristic.uuid,
characteristic.handle,
)
)
if not esphome_services.services:
# If we got no services, we must have disconnected
# or something went wrong on the ESP32's BLE stack.
raise BleakError("Failed to get services from remote esp")
self.services = services
_LOGGER.debug(
"%s: %s - %s: Cached services saved",
self._source,
self._ble_device.name,
self._ble_device.address,
)
entry_data.set_gatt_services_cache(address_as_int, services)
return services
def _resolve_characteristic(
self, char_specifier: BleakGATTCharacteristic | int | str | uuid.UUID
) -> BleakGATTCharacteristic:
"""Resolve a characteristic specifier to a BleakGATTCharacteristic object."""
if not isinstance(char_specifier, BleakGATTCharacteristic):
characteristic = self.services.get_characteristic(char_specifier)
else:
characteristic = char_specifier
if not characteristic:
raise BleakError(f"Characteristic {char_specifier} was not found!")
return characteristic
async def clear_cache(self) -> None:
"""Clear the GATT cache."""
self.entry_data.clear_gatt_services_cache(self._address_as_int)
self.entry_data.clear_gatt_mtu_cache(self._address_as_int)
@verify_connected
@api_error_as_bleak_error
async def read_gatt_char(
self,
char_specifier: BleakGATTCharacteristic | int | str | uuid.UUID,
**kwargs: Any,
) -> bytearray:
"""Perform read operation on the specified GATT characteristic.
Args:
char_specifier (BleakGATTCharacteristic, int, str or UUID): The characteristic to read from,
specified by either integer handle, UUID or directly by the
BleakGATTCharacteristic object representing it.
Returns:
(bytearray) The read data.
"""
characteristic = self._resolve_characteristic(char_specifier)
return await self._client.bluetooth_gatt_read(
self._address_as_int, characteristic.handle, GATT_READ_TIMEOUT
)
@verify_connected
@api_error_as_bleak_error
async def read_gatt_descriptor(self, handle: int, **kwargs: Any) -> bytearray:
"""Perform read operation on the specified GATT descriptor.
Args:
handle (int): The handle of the descriptor to read from.
Returns:
(bytearray) The read data.
"""
return await self._client.bluetooth_gatt_read_descriptor(
self._address_as_int, handle, GATT_READ_TIMEOUT
)
@verify_connected
@api_error_as_bleak_error
async def write_gatt_char(
self,
char_specifier: BleakGATTCharacteristic | int | str | uuid.UUID,
data: bytes | bytearray | memoryview,
response: bool = False,
) -> None:
"""Perform a write operation of the specified GATT characteristic.
Args:
char_specifier (BleakGATTCharacteristic, int, str or UUID): The characteristic to write
to, specified by either integer handle, UUID or directly by the
BleakGATTCharacteristic object representing it.
data (bytes or bytearray): The data to send.
response (bool): If write-with-response operation should be done. Defaults to `False`.
"""
characteristic = self._resolve_characteristic(char_specifier)
await self._client.bluetooth_gatt_write(
self._address_as_int, characteristic.handle, bytes(data), response
)
@verify_connected
@api_error_as_bleak_error
async def write_gatt_descriptor(
self, handle: int, data: bytes | bytearray | memoryview
) -> None:
"""Perform a write operation on the specified GATT descriptor.
Args:
handle (int): The handle of the descriptor to read from.
data (bytes or bytearray): The data to send.
"""
await self._client.bluetooth_gatt_write_descriptor(
self._address_as_int, handle, bytes(data)
)
@verify_connected
@api_error_as_bleak_error
async def start_notify(
self,
characteristic: BleakGATTCharacteristic,
callback: NotifyCallback,
**kwargs: Any,
) -> None:
"""Activate notifications/indications on a characteristic.
Callbacks must accept two inputs. The first will be a integer handle of the characteristic generating the
data and the second will be a ``bytearray`` containing the data sent from the connected server.
.. code-block:: python
def callback(sender: int, data: bytearray):
print(f"{sender}: {data}")
client.start_notify(char_uuid, callback)
Args:
char_specifier (BleakGATTCharacteristic, int, str or UUID): The characteristic to activate
notifications/indications on a characteristic, specified by either integer handle,
UUID or directly by the BleakGATTCharacteristic object representing it.
callback (function): The function to be called on notification.
"""
ble_handle = characteristic.handle
if ble_handle in self._notify_cancels:
raise BleakError(
"Notifications are already enabled on "
f"service:{characteristic.service_uuid} "
f"characteristic:{characteristic.uuid} "
f"handle:{ble_handle}"
)
if (
"notify" not in characteristic.properties
and "indicate" not in characteristic.properties
):
raise BleakError(
f"Characteristic {characteristic.uuid} does not have notify or indicate property set."
)
self._notify_cancels[
ble_handle
] = await self._client.bluetooth_gatt_start_notify(
self._address_as_int,
ble_handle,
lambda handle, data: callback(data),
)
if self._connection_version < MIN_BLUETOOTH_PROXY_VERSION_HAS_CACHE:
return
# For connection v3 we are responsible for enabling notifications
# on the cccd (characteristic client config descriptor) handle since
# the esp32 will not have resolved the characteristic descriptors to
# save memory since doing so can exhaust the memory and cause a soft
# reset
cccd_descriptor = characteristic.get_descriptor(CCCD_UUID)
if not cccd_descriptor:
raise BleakError(
f"Characteristic {characteristic.uuid} does not have a "
"characteristic client config descriptor."
)
_LOGGER.debug(
"%s: %s - %s: Writing to CCD descriptor %s for notifications with properties=%s",
self._source,
self._ble_device.name,
self._ble_device.address,
cccd_descriptor.handle,
characteristic.properties,
)
supports_notify = "notify" in characteristic.properties
await self._client.bluetooth_gatt_write_descriptor(
self._address_as_int,
cccd_descriptor.handle,
CCCD_NOTIFY_BYTES if supports_notify else CCCD_INDICATE_BYTES,
wait_for_response=False,
)
@api_error_as_bleak_error
async def stop_notify(
self,
char_specifier: BleakGATTCharacteristic | int | str | uuid.UUID,
) -> None:
"""Deactivate notification/indication on a specified characteristic.
Args:
char_specifier (BleakGATTCharacteristic, int, str or UUID): The characteristic to deactivate
notification/indication on, specified by either integer handle, UUID or
directly by the BleakGATTCharacteristic object representing it.
"""
characteristic = self._resolve_characteristic(char_specifier)
# Do not raise KeyError if notifications are not enabled on this characteristic
# to be consistent with the behavior of the BlueZ backend
if notify_cancel := self._notify_cancels.pop(characteristic.handle, None):
notify_stop, _ = notify_cancel
await notify_stop()
def __del__(self) -> None:
"""Destructor to make sure the connection state is unsubscribed."""
if self._cancel_connection_state:
_LOGGER.warning(
"%s: %s - %s: ESPHomeClient bleak client was not properly disconnected before destruction",
self._source,
self._ble_device.name,
self._ble_device.address,
)
if not self._hass.loop.is_closed():
self._hass.loop.call_soon_threadsafe(self._async_disconnected_cleanup)