class BleakClientDotNet(BaseBleakClient):
"""The native Windows Bleak Client.
Implemented using `pythonnet <https://pythonnet.github.io/>`_, a package that provides an integration to the .NET
Common Language Runtime (CLR). Therefore, much of the code below has a distinct C# feel.
Args:
address_or_ble_device (`BLEDevice` or str): The Bluetooth address of the BLE peripheral to connect to or the `BLEDevice` object representing it.
Keyword Args:
timeout (float): Timeout for required ``BleakScanner.find_device_by_address`` call. Defaults to 10.0.
"""
def __init__(self, address_or_ble_device: Union[BLEDevice, str], **kwargs):
super(BleakClientDotNet, self).__init__(address_or_ble_device,
**kwargs)
# Backend specific. Python.NET objects.
if isinstance(address_or_ble_device, BLEDevice):
self._device_info = address_or_ble_device.details.BluetoothAddress
else:
self._device_info = None
self._requester = None
self._bridge = None
self._address_type = (
kwargs["address_type"] if "address_type" in kwargs
and kwargs["address_type"] in ("public", "random") else None)
def __str__(self):
return "BleakClientDotNet ({0})".format(self.address)
# Connectivity methods
async def connect(self, **kwargs) -> bool:
"""Connect to the specified GATT server.
Keyword Args:
timeout (float): Timeout for required ``BleakScanner.find_device_by_address`` call. Defaults to 10.0.
Returns:
Boolean representing connection status.
"""
# Create a new BleakBridge here.
self._bridge = Bridge()
# Try to find the desired device.
if self._device_info is None:
timeout = kwargs.get("timeout", self._timeout)
device = await BleakScannerDotNet.find_device_by_address(
self.address, timeout=timeout)
if device:
self._device_info = device.details.BluetoothAddress
else:
raise BleakError(
"Device with address {0} was not found.".format(
self.address))
logger.debug("Connecting to BLE device @ {0}".format(self.address))
args = [UInt64(self._device_info)]
if self._address_type is not None:
args.append(BluetoothAddressType.Public if self._address_type ==
"public" else BluetoothAddressType.Random)
self._requester = await wrap_IAsyncOperation(
IAsyncOperation[BluetoothLEDevice](
BluetoothLEDevice.FromBluetoothAddressAsync(*args)),
return_type=BluetoothLEDevice,
)
loop = asyncio.get_event_loop()
def _ConnectionStatusChanged_Handler(sender, args):
logger.debug("_ConnectionStatusChanged_Handler: %d",
sender.ConnectionStatus)
if (sender.ConnectionStatus
== BluetoothConnectionStatus.Disconnected
and self._disconnected_callback):
loop.call_soon_threadsafe(self._disconnected_callback, self)
self._requester.ConnectionStatusChanged += _ConnectionStatusChanged_Handler
# Obtain services, which also leads to connection being established.
services = await self.get_services()
connected = False
if self._services_resolved:
# If services has been resolved, then we assume that we are connected. This is due to
# some issues with getting `is_connected` to give correct response here.
connected = True
else:
for _ in range(5):
await asyncio.sleep(0.2)
connected = await self.is_connected()
if connected:
break
if connected:
logger.debug("Connection successful.")
else:
raise BleakError("Connection to {0} was not successful!".format(
self.address))
return connected
async def disconnect(self) -> bool:
"""Disconnect from the specified GATT server.
Returns:
Boolean representing if device is disconnected.
"""
logger.debug("Disconnecting from BLE device...")
# Remove notifications. Remove them first in the BleakBridge and then clear
# remaining notifications in Python as well.
for characteristic in self.services.characteristics.values():
self._bridge.RemoveValueChangedCallback(characteristic.obj)
self._notification_callbacks.clear()
# Dispose all service components that we have requested and created.
for service in self.services:
service.obj.Dispose()
self.services = BleakGATTServiceCollection()
self._services_resolved = False
# Dispose of the BluetoothLEDevice and see that the connection
# status is now Disconnected.
self._requester.Dispose()
is_disconnected = (self._requester.ConnectionStatus ==
BluetoothConnectionStatus.Disconnected)
self._requester = None
# Set device info to None as well.
self._device_info = None
# Finally, dispose of the Bleak Bridge as well.
self._bridge.Dispose()
self._bridge = None
return is_disconnected
async def is_connected(self) -> bool:
"""Check connection status between this client and the server.
Returns:
Boolean representing connection status.
"""
if self._requester:
return (self._requester.ConnectionStatus ==
BluetoothConnectionStatus.Connected)
else:
return False
async def pair(self, protection_level=None, **kwargs) -> bool:
"""Attempts to pair with the device.
Keyword Args:
protection_level:
DevicePairingProtectionLevel
1: None - Pair the device using no levels of protection.
2: Encryption - Pair the device using encryption.
3: EncryptionAndAuthentication - Pair the device using encryption and authentication.
Returns:
Boolean regarding success of pairing.
"""
if (self._requester.DeviceInformation.Pairing.CanPair
and not self._requester.DeviceInformation.Pairing.IsPaired):
# Currently only supporting Just Works solutions...
ceremony = DevicePairingKinds.ConfirmOnly
custom_pairing = self._requester.DeviceInformation.Pairing.Custom
def handler(sender, args):
args.Accept()
custom_pairing.PairingRequested += handler
if protection_level:
raise NotImplementedError(
"Cannot set minimally required protection level yet...")
else:
pairing_result = await wrap_IAsyncOperation(
IAsyncOperation[DevicePairingResult](
custom_pairing.PairAsync.Overloads[DevicePairingKinds](
ceremony)),
return_type=DevicePairingResult,
)
try:
custom_pairing.PairingRequested -= handler
except Exception as e:
# TODO: Find a way to remove WinRT events...
pass
finally:
del handler
if pairing_result.Status not in (
DevicePairingResultStatus.Paired,
DevicePairingResultStatus.AlreadyPaired,
):
raise BleakError("Could not pair with device: {0}: {1}".format(
pairing_result.Status,
_pairing_statuses.get(pairing_result.Status),
))
else:
logger.info(
"Paired to device with protection level {0}.".format(
pairing_result.ProtectionLevelUsed))
return self._requester.DeviceInformation.Pairing.IsPaired
async def unpair(self) -> bool:
"""Attempts to unpair from the device.
Returns:
Boolean on whether the unparing was successful.
"""
if self._requester.DeviceInformation.Pairing.IsPaired:
unpairing_result = await wrap_IAsyncOperation(
IAsyncOperation[DeviceUnpairingResult](
self._requester.DeviceInformation.Pairing.UnpairAsync()),
return_type=DeviceUnpairingResult,
)
if unpairing_result.Status not in (
DevicePairingResultStatus.Paired,
DevicePairingResultStatus.AlreadyPaired,
):
raise BleakError(
"Could not unpair with device: {0}: {1}".format(
unpairing_result.Status,
_unpairing_statuses.get(unpairing_result.Status),
))
else:
logger.info("Unpaired with device.")
return not self._requester.DeviceInformation.Pairing.IsPaired
# GATT services methods
async def get_services(self) -> BleakGATTServiceCollection:
"""Get all services registered for this GATT server.
Returns:
A :py:class:`bleak.backends.service.BleakGATTServiceCollection` with this device's services tree.
"""
# Return the Service Collection.
if self._services_resolved:
return self.services
else:
logger.debug("Get Services...")
services_result = await wrap_IAsyncOperation(
IAsyncOperation[GattDeviceServicesResult](
self._requester.GetGattServicesAsync()),
return_type=GattDeviceServicesResult,
)
if services_result.Status != GattCommunicationStatus.Success:
if services_result.Status == GattCommunicationStatus.ProtocolError:
raise BleakDotNetTaskError(
"Could not get GATT services: {0} (Error: 0x{1:02X}: {2})"
.format(
_communication_statues.get(services_result.Status,
""),
services_result.ProtocolError,
CONTROLLER_ERROR_CODES.get(
services_result.ProtocolError, "Unknown"),
))
else:
raise BleakDotNetTaskError(
"Could not get GATT services: {0}".format(
_communication_statues.get(services_result.Status,
"")))
for service in services_result.Services:
characteristics_result = await wrap_IAsyncOperation(
IAsyncOperation[GattCharacteristicsResult](
service.GetCharacteristicsAsync()),
return_type=GattCharacteristicsResult,
)
self.services.add_service(BleakGATTServiceDotNet(service))
if characteristics_result.Status != GattCommunicationStatus.Success:
if (characteristics_result.Status ==
GattCommunicationStatus.ProtocolError):
raise BleakDotNetTaskError(
"Could not get GATT characteristics for {0}: {1} (Error: 0x{2:02X}: {3})"
.format(
service,
_communication_statues.get(
characteristics_result.Status, ""),
characteristics_result.ProtocolError,
CONTROLLER_ERROR_CODES.get(
characteristics_result.ProtocolError,
"Unknown"),
))
else:
raise BleakDotNetTaskError(
"Could not get GATT characteristics for {0}: {1}".
format(
service,
_communication_statues.get(
characteristics_result.Status, ""),
))
for characteristic in characteristics_result.Characteristics:
descriptors_result = await wrap_IAsyncOperation(
IAsyncOperation[GattDescriptorsResult](
characteristic.GetDescriptorsAsync()),
return_type=GattDescriptorsResult,
)
self.services.add_characteristic(
BleakGATTCharacteristicDotNet(characteristic))
if descriptors_result.Status != GattCommunicationStatus.Success:
if (characteristics_result.Status ==
GattCommunicationStatus.ProtocolError):
raise BleakDotNetTaskError(
"Could not get GATT descriptors for {0}: {1} (Error: 0x{2:02X}: {3})"
.format(
service,
_communication_statues.get(
descriptors_result.Status, ""),
descriptors_result.ProtocolError,
CONTROLLER_ERROR_CODES.get(
descriptors_result.ProtocolError,
"Unknown"),
))
else:
raise BleakDotNetTaskError(
"Could not get GATT descriptors for {0}: {1}".
format(
characteristic,
_communication_statues.get(
descriptors_result.Status, ""),
))
for descriptor in list(descriptors_result.Descriptors):
self.services.add_descriptor(
BleakGATTDescriptorDotNet(
descriptor,
characteristic.Uuid.ToString(),
int(characteristic.AttributeHandle),
))
logger.info("Services resolved for %s", str(self))
self._services_resolved = True
return self.services
# I/O methods
async def read_gatt_char(self,
char_specifier: Union[BleakGATTCharacteristic,
int, str, uuid.UUID],
use_cached=False,
**kwargs) -> 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.
use_cached (bool): `False` forces Windows to read the value from the
device again and not use its own cached value. Defaults to `False`.
Returns:
(bytearray) The read data.
"""
if not isinstance(char_specifier, BleakGATTCharacteristic):
characteristic = self.services.get_characteristic(char_specifier)
else:
characteristic = char_specifier
if not characteristic:
raise BleakError(
"Characteristic {0} was not found!".format(char_specifier))
read_result = await wrap_IAsyncOperation(
IAsyncOperation[GattReadResult](characteristic.obj.ReadValueAsync(
BluetoothCacheMode.
Cached if use_cached else BluetoothCacheMode.Uncached)),
return_type=GattReadResult,
)
if read_result.Status == GattCommunicationStatus.Success:
with BleakDataReader(read_result.Value) as reader:
value = bytearray(reader.read())
logger.debug("Read Characteristic {0} : {1}".format(
characteristic.uuid, value))
else:
if read_result.Status == GattCommunicationStatus.ProtocolError:
raise BleakDotNetTaskError(
"Could not get GATT characteristics for {0}: {1} (Error: 0x{2:02X}: {3})"
.format(
characteristic.uuid,
_communication_statues.get(read_result.Status, ""),
read_result.ProtocolError,
CONTROLLER_ERROR_CODES.get(read_result.ProtocolError,
"Unknown"),
))
else:
raise BleakError(
"Could not read characteristic value for {0}: {1}".format(
characteristic.uuid,
_communication_statues.get(read_result.Status, ""),
))
return value
async def read_gatt_descriptor(self,
handle: int,
use_cached=False,
**kwargs) -> bytearray:
"""Perform read operation on the specified GATT descriptor.
Args:
handle (int): The handle of the descriptor to read from.
use_cached (bool): `False` forces Windows to read the value from the
device again and not use its own cached value. Defaults to `False`.
Returns:
(bytearray) The read data.
"""
descriptor = self.services.get_descriptor(handle)
if not descriptor:
raise BleakError(
"Descriptor with handle {0} was not found!".format(handle))
read_result = await wrap_IAsyncOperation(
IAsyncOperation[GattReadResult](descriptor.obj.ReadValueAsync(
BluetoothCacheMode.
Cached if use_cached else BluetoothCacheMode.Uncached)),
return_type=GattReadResult,
)
if read_result.Status == GattCommunicationStatus.Success:
with BleakDataReader(read_result.Value) as reader:
value = bytearray(reader.read())
logger.debug("Read Descriptor {0} : {1}".format(handle, value))
else:
if read_result.Status == GattCommunicationStatus.ProtocolError:
raise BleakDotNetTaskError(
"Could not get GATT characteristics for {0}: {1} (Error: 0x{2:02X}: {3})"
.format(
descriptor.uuid,
_communication_statues.get(read_result.Status, ""),
read_result.ProtocolError,
CONTROLLER_ERROR_CODES.get(read_result.ProtocolError,
"Unknown"),
))
else:
raise BleakError(
"Could not read Descriptor value for {0}: {1}".format(
descriptor.uuid,
_communication_statues.get(read_result.Status, ""),
))
return value
async def write_gatt_char(
self,
char_specifier: Union[BleakGATTCharacteristic, int, str, uuid.UUID],
data: bytearray,
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`.
"""
if not isinstance(char_specifier, BleakGATTCharacteristic):
characteristic = self.services.get_characteristic(char_specifier)
else:
characteristic = char_specifier
if not characteristic:
raise BleakError(
"Characteristic {} was not found!".format(char_specifier))
with BleakDataWriter(data) as writer:
response = (GattWriteOption.WriteWithResponse
if response else GattWriteOption.WriteWithoutResponse)
write_result = await wrap_IAsyncOperation(
IAsyncOperation[GattWriteResult](
characteristic.obj.WriteValueWithResultAsync(
writer.detach_buffer(), response)),
return_type=GattWriteResult,
)
if write_result.Status == GattCommunicationStatus.Success:
logger.debug("Write Characteristic {0} : {1}".format(
characteristic.uuid, data))
else:
if write_result.Status == GattCommunicationStatus.ProtocolError:
raise BleakError(
"Could not write value {0} to characteristic {1}: {2} (Error: 0x{3:02X}: {4})"
.format(
data,
characteristic.uuid,
_communication_statues.get(write_result.Status, ""),
write_result.ProtocolError,
CONTROLLER_ERROR_CODES.get(write_result.ProtocolError,
"Unknown"),
))
else:
raise BleakError(
"Could not write value {0} to characteristic {1}: {2}".
format(
data,
characteristic.uuid,
_communication_statues.get(write_result.Status, ""),
))
async def write_gatt_descriptor(self, handle: int,
data: bytearray) -> 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.
"""
descriptor = self.services.get_descriptor(handle)
if not descriptor:
raise BleakError(
"Descriptor with handle {0} was not found!".format(handle))
with BleakDataWriter(data) as writer:
write_result = await wrap_IAsyncOperation(
IAsyncOperation[GattWriteResult](
descriptor.obj.WriteValueAsync(writer.DetachBuffer())),
return_type=GattWriteResult,
)
if write_result.Status == GattCommunicationStatus.Success:
logger.debug("Write Descriptor {0} : {1}".format(handle, data))
else:
if write_result.Status == GattCommunicationStatus.ProtocolError:
raise BleakError(
"Could not write value {0} to characteristic {1}: {2} (Error: 0x{3:02X}: {4})"
.format(
data,
descriptor.uuid,
_communication_statues.get(write_result.Status, ""),
write_result.ProtocolError,
CONTROLLER_ERROR_CODES.get(write_result.ProtocolError,
"Unknown"),
))
else:
raise BleakError(
"Could not write value {0} to descriptor {1}: {2}".format(
data,
descriptor.uuid,
_communication_statues.get(write_result.Status, ""),
))
async def start_notify(self, char_specifier: Union[BleakGATTCharacteristic,
int, str, uuid.UUID],
callback: Callable[[int, bytearray],
None], **kwargs) -> 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.
"""
if not isinstance(char_specifier, BleakGATTCharacteristic):
characteristic = self.services.get_characteristic(char_specifier)
else:
characteristic = char_specifier
if not characteristic:
raise BleakError(
"Characteristic {0} not found!".format(char_specifier))
if self._notification_callbacks.get(characteristic.handle):
await self.stop_notify(characteristic)
status = await self._start_notify(characteristic, callback)
if status != GattCommunicationStatus.Success:
# TODO: Find out how to get the ProtocolError code that describes a potential GattCommunicationStatus.ProtocolError result.
raise BleakError("Could not start notify on {0}: {1}".format(
characteristic.uuid, _communication_statues.get(status, "")))
async def _start_notify(
self,
characteristic: BleakGATTCharacteristic,
callback: Callable[[str, Any], Any],
):
"""Internal method performing call to BleakUWPBridge method.
Args:
characteristic: The BleakGATTCharacteristic to start notification on.
callback: The function to be called on notification.
Returns:
(int) The GattCommunicationStatus of the operation.
"""
characteristic_obj = characteristic.obj
if (characteristic_obj.CharacteristicProperties
& GattCharacteristicProperties.Indicate):
cccd = GattClientCharacteristicConfigurationDescriptorValue.Indicate
elif (characteristic_obj.CharacteristicProperties
& GattCharacteristicProperties.Notify):
cccd = GattClientCharacteristicConfigurationDescriptorValue.Notify
else:
cccd = getattr(
GattClientCharacteristicConfigurationDescriptorValue, "None")
try:
# TODO: Enable adding multiple handlers!
self._notification_callbacks[
characteristic.handle] = TypedEventHandler[
GattCharacteristic,
GattValueChangedEventArgs](_notification_wrapper(
callback, asyncio.get_event_loop()))
self._bridge.AddValueChangedCallback(
characteristic_obj,
self._notification_callbacks[characteristic.handle])
except Exception as e:
logger.debug("Start Notify problem: {0}".format(e))
if characteristic_obj.Uuid.ToString(
) in self._notification_callbacks:
callback = self._notification_callbacks.pop(
characteristic.handle)
self._bridge.RemoveValueChangedCallback(characteristic_obj)
del callback
return GattCommunicationStatus.AccessDenied
status = await wrap_IAsyncOperation(
IAsyncOperation[GattCommunicationStatus](
characteristic_obj.
WriteClientCharacteristicConfigurationDescriptorAsync(cccd)),
return_type=GattCommunicationStatus,
)
if status != GattCommunicationStatus.Success:
# This usually happens when a device reports that it support indicate,
# but it actually doesn't.
if characteristic.handle in self._notification_callbacks:
callback = self._notification_callbacks.pop(
characteristic.handle)
self._bridge.RemoveValueChangedCallback(characteristic_obj)
del callback
return GattCommunicationStatus.AccessDenied
return status
async def stop_notify(
self, char_specifier: Union[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.
"""
if not isinstance(char_specifier, BleakGATTCharacteristic):
characteristic = self.services.get_characteristic(char_specifier)
else:
characteristic = char_specifier
if not characteristic:
raise BleakError(
"Characteristic {} not found!".format(char_specifier))
status = await wrap_IAsyncOperation(
IAsyncOperation[GattCommunicationStatus](
characteristic.obj.
WriteClientCharacteristicConfigurationDescriptorAsync(
getattr(
GattClientCharacteristicConfigurationDescriptorValue,
"None"))),
return_type=GattCommunicationStatus,
)
if status != GattCommunicationStatus.Success:
raise BleakError("Could not stop notify on {0}: {1}".format(
characteristic.uuid, _communication_statues.get(status, "")))
else:
callback = self._notification_callbacks.pop(characteristic.handle)
self._bridge.RemoveValueChangedCallback(characteristic.obj)
del callback
class BleakClientDotNet(BaseBleakClient):
"""The native Windows Bleak Client.
Implemented using `pythonnet <https://pythonnet.github.io/>`_, a package that provides an integration to the .NET
Common Language Runtime (CLR). Therefore, much of the code below has a distinct C# feel.
Args:
address (str): The MAC address of the BLE peripheral to connect to.
loop (asyncio.events.AbstractEventLoop): The event loop to use.
Keyword Args:
timeout (float): Timeout for required ``discover`` call. Defaults to 2.0.
"""
def __init__(self, address: str, loop: AbstractEventLoop = None, **kwargs):
super(BleakClientDotNet, self).__init__(address, loop, **kwargs)
# Backend specific. Python.NET objects.
self._device_info = None
self._requester = None
self._bridge = Bridge()
self._address_type = (
kwargs["address_type"] if "address_type" in kwargs
and kwargs["address_type"] in ("public", "random") else None)
def __str__(self):
return "BleakClientDotNet ({0})".format(self.address)
# Connectivity methods
async def connect(self, **kwargs) -> bool:
"""Connect to the specified GATT server.
Keyword Args:
timeout (float): Timeout for required ``discover`` call. Defaults to 2.0.
Returns:
Boolean representing connection status.
"""
# Try to find the desired device.
timeout = kwargs.get("timeout", self._timeout)
devices = await discover(timeout=timeout, loop=self.loop)
sought_device = list(
filter(lambda x: x.address.upper() == self.address.upper(),
devices))
if len(sought_device):
self._device_info = sought_device[0].details
else:
raise BleakError("Device with address {0} was "
"not found.".format(self.address))
logger.debug("Connecting to BLE device @ {0}".format(self.address))
args = [UInt64(self._device_info.BluetoothAddress)]
if self._address_type is not None:
args.append(BluetoothAddressType.Public if self._address_type ==
"public" else BluetoothAddressType.Random)
self._requester = await wrap_IAsyncOperation(
IAsyncOperation[BluetoothLEDevice](
BluetoothLEDevice.FromBluetoothAddressAsync(*args)),
return_type=BluetoothLEDevice,
loop=self.loop,
)
def _ConnectionStatusChanged_Handler(sender, args):
logger.debug("_ConnectionStatusChanged_Handler: " +
args.ToString())
self._requester.ConnectionStatusChanged += _ConnectionStatusChanged_Handler
# Obtain services, which also leads to connection being established.
services = await self.get_services()
connected = False
if self._services_resolved:
# If services has been resolved, then we assume that we are connected. This is due to
# some issues with getting `is_connected` to give correct response here.
connected = True
else:
for _ in range(5):
await asyncio.sleep(0.2, loop=self.loop)
connected = await self.is_connected()
if connected:
break
if connected:
logger.debug("Connection successful.")
else:
raise BleakError("Connection to {0} was not successful!".format(
self.address))
return connected
async def disconnect(self) -> bool:
"""Disconnect from the specified GATT server.
Returns:
Boolean representing connection status.
"""
logger.debug("Disconnecting from BLE device...")
# Remove notifications
# TODO: Make sure all notifications are removed prior to Dispose.
# Dispose all components that we have requested and created.
for service in self.services:
service.obj.Dispose()
self.services = BleakGATTServiceCollection()
self._requester.Dispose()
self._requester = None
return not await self.is_connected()
async def is_connected(self) -> bool:
"""Check connection status between this client and the server.
Returns:
Boolean representing connection status.
"""
if self._requester:
return (self._requester.ConnectionStatus ==
BluetoothConnectionStatus.Connected)
else:
return False
def set_disconnected_callback(self, callback: Callable[[BaseBleakClient],
None],
**kwargs) -> None:
"""Set the disconnected callback.
N.B. This is not implemented in the .NET backend yet.
Args:
callback: callback to be called on disconnection.
"""
raise NotImplementedError(
"This is not implemented in the .NET backend yet")
# GATT services methods
async def get_services(self) -> BleakGATTServiceCollection:
"""Get all services registered for this GATT server.
Returns:
A :py:class:`bleak.backends.service.BleakGATTServiceCollection` with this device's services tree.
"""
# Return the Service Collection.
if self._services_resolved:
return self.services
else:
logger.debug("Get Services...")
services_result = await wrap_IAsyncOperation(
IAsyncOperation[GattDeviceServicesResult](
self._requester.GetGattServicesAsync()),
return_type=GattDeviceServicesResult,
loop=self.loop,
)
if services_result.Status != GattCommunicationStatus.Success:
if services_result.Status == GattCommunicationStatus.ProtocolError:
raise BleakDotNetTaskError(
"Could not get GATT services: {0} (Error: 0x{1:02X})".
format(
_communication_statues.get(services_result.Status,
""),
services_result.ProtocolError,
))
else:
raise BleakDotNetTaskError(
"Could not get GATT services: {0}".format(
_communication_statues.get(services_result.Status,
"")))
# TODO: Check if fetching yeilds failures...
for service in services_result.Services:
characteristics_result = await wrap_IAsyncOperation(
IAsyncOperation[GattCharacteristicsResult](
service.GetCharacteristicsAsync()),
return_type=GattCharacteristicsResult,
loop=self.loop,
)
self.services.add_service(BleakGATTServiceDotNet(service))
if characteristics_result.Status != GattCommunicationStatus.Success:
if (characteristics_result.Status ==
GattCommunicationStatus.ProtocolError):
raise BleakDotNetTaskError(
"Could not get GATT characteristics for {0}: {1} (Error: 0x{2:02X})"
.format(
service,
_communication_statues.get(
characteristics_result.Status, ""),
characteristics_result.ProtocolError,
))
else:
raise BleakDotNetTaskError(
"Could not get GATT characteristics for {0}: {1}".
format(
service,
_communication_statues.get(
characteristics_result.Status, ""),
))
for characteristic in characteristics_result.Characteristics:
descriptors_result = await wrap_IAsyncOperation(
IAsyncOperation[GattDescriptorsResult](
characteristic.GetDescriptorsAsync()),
return_type=GattDescriptorsResult,
loop=self.loop,
)
self.services.add_characteristic(
BleakGATTCharacteristicDotNet(characteristic))
if descriptors_result.Status != GattCommunicationStatus.Success:
if (characteristics_result.Status ==
GattCommunicationStatus.ProtocolError):
raise BleakDotNetTaskError(
"Could not get GATT descriptors for {0}: {1} (Error: 0x{2:02X})"
.format(
service,
_communication_statues.get(
descriptors_result.Status, ""),
descriptors_result.ProtocolError,
))
else:
raise BleakDotNetTaskError(
"Could not get GATT descriptors for {0}: {1}".
format(
characteristic,
_communication_statues.get(
descriptors_result.Status, ""),
))
for descriptor in list(descriptors_result.Descriptors):
self.services.add_descriptor(
BleakGATTDescriptorDotNet(
descriptor,
characteristic.Uuid.ToString(),
int(characteristic.AttributeHandle),
))
self._services_resolved = True
return self.services
# I/O methods
async def read_gatt_char(self,
char_specifier: Union[BleakGATTCharacteristic,
int, str, uuid.UUID],
use_cached=False,
**kwargs) -> 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.
use_cached (bool): `False` forces Windows to read the value from the
device again and not use its own cached value. Defaults to `False`.
Returns:
(bytearray) The read data.
"""
if not isinstance(char_specifier, BleakGATTCharacteristic):
characteristic = self.services.get_characteristic(char_specifier)
else:
characteristic = char_specifier
if not characteristic:
raise BleakError(
"Characteristic {0} was not found!".format(char_specifier))
read_result = await wrap_IAsyncOperation(
IAsyncOperation[GattReadResult](characteristic.obj.ReadValueAsync(
BluetoothCacheMode.
Cached if use_cached else BluetoothCacheMode.Uncached)),
return_type=GattReadResult,
loop=self.loop,
)
if read_result.Status == GattCommunicationStatus.Success:
reader = DataReader.FromBuffer(IBuffer(read_result.Value))
output = Array.CreateInstance(Byte, reader.UnconsumedBufferLength)
reader.ReadBytes(output)
value = bytearray(output)
logger.debug("Read Characteristic {0} : {1}".format(
characteristic.uuid, value))
else:
if read_result.Status == GattCommunicationStatus.ProtocolError:
raise BleakDotNetTaskError(
"Could not get GATT characteristics for {0}: {1} (Error: 0x{2:02X})"
.format(
characteristic.uuid,
_communication_statues.get(read_result.Status, ""),
read_result.ProtocolError,
))
else:
raise BleakError(
"Could not read characteristic value for {0}: {1}".format(
characteristic.uuid,
_communication_statues.get(read_result.Status, ""),
))
return value
async def read_gatt_descriptor(self,
handle: int,
use_cached=False,
**kwargs) -> bytearray:
"""Perform read operation on the specified GATT descriptor.
Args:
handle (int): The handle of the descriptor to read from.
use_cached (bool): `False` forces Windows to read the value from the
device again and not use its own cached value. Defaults to `False`.
Returns:
(bytearray) The read data.
"""
descriptor = self.services.get_descriptor(handle)
if not descriptor:
raise BleakError(
"Descriptor with handle {0} was not found!".format(handle))
read_result = await wrap_IAsyncOperation(
IAsyncOperation[GattReadResult](descriptor.obj.ReadValueAsync(
BluetoothCacheMode.
Cached if use_cached else BluetoothCacheMode.Uncached)),
return_type=GattReadResult,
loop=self.loop,
)
if read_result.Status == GattCommunicationStatus.Success:
reader = DataReader.FromBuffer(IBuffer(read_result.Value))
output = Array.CreateInstance(Byte, reader.UnconsumedBufferLength)
reader.ReadBytes(output)
value = bytearray(output)
logger.debug("Read Descriptor {0} : {1}".format(handle, value))
else:
if read_result.Status == GattCommunicationStatus.ProtocolError:
raise BleakDotNetTaskError(
"Could not get GATT characteristics for {0}: {1} (Error: 0x{2:02X})"
.format(
descriptor.uuid,
_communication_statues.get(read_result.Status, ""),
read_result.ProtocolError,
))
else:
raise BleakError(
"Could not read Descriptor value for {0}: {1}".format(
descriptor.uuid,
_communication_statues.get(read_result.Status, ""),
))
return value
async def write_gatt_char(
self,
char_specifier: Union[BleakGATTCharacteristic, int, str, uuid.UUID],
data: bytearray,
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`.
"""
if not isinstance(char_specifier, BleakGATTCharacteristic):
characteristic = self.services.get_characteristic(char_specifier)
else:
characteristic = char_specifier
if not characteristic:
raise BleakError(
"Characteristic {} was not found!".format(char_specifier))
writer = DataWriter()
writer.WriteBytes(Array[Byte](data))
response = (GattWriteOption.WriteWithResponse
if response else GattWriteOption.WriteWithoutResponse)
write_result = await wrap_IAsyncOperation(
IAsyncOperation[GattWriteResult](
characteristic.obj.WriteValueWithResultAsync(
writer.DetachBuffer(), response)),
return_type=GattWriteResult,
loop=self.loop,
)
if write_result.Status == GattCommunicationStatus.Success:
logger.debug("Write Characteristic {0} : {1}".format(
characteristic.uuid, data))
else:
if write_result.Status == GattCommunicationStatus.ProtocolError:
raise BleakError(
"Could not write value {0} to characteristic {1}: {2} (Error: 0x{3:02X})"
.format(
data,
characteristic.uuid,
_communication_statues.get(write_result.Status, ""),
write_result.ProtocolError,
))
else:
raise BleakError(
"Could not write value {0} to characteristic {1}: {2}".
format(
data,
characteristic.uuid,
_communication_statues.get(write_result.Status, ""),
))
async def write_gatt_descriptor(self, handle: int,
data: bytearray) -> 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.
"""
descriptor = self.services.get_descriptor(handle)
if not descriptor:
raise BleakError(
"Descriptor with handle {0} was not found!".format(handle))
writer = DataWriter()
writer.WriteBytes(Array[Byte](data))
write_result = await wrap_IAsyncOperation(
IAsyncOperation[GattWriteResult](descriptor.obj.WriteValueAsync(
writer.DetachBuffer())),
return_type=GattWriteResult,
loop=self.loop,
)
if write_result.Status == GattCommunicationStatus.Success:
logger.debug("Write Descriptor {0} : {1}".format(handle, data))
else:
if write_result.Status == GattCommunicationStatus.ProtocolError:
raise BleakError(
"Could not write value {0} to characteristic {1}: {2} (Error: 0x{3:02X})"
.format(
data,
descriptor.uuid,
_communication_statues.get(write_result.Status, ""),
write_result.ProtocolError,
))
else:
raise BleakError(
"Could not write value {0} to descriptor {1}: {2}".format(
data,
descriptor.uuid,
_communication_statues.get(write_result.Status, ""),
))
async def start_notify(self, char_specifier: Union[BleakGATTCharacteristic,
int, str, uuid.UUID],
callback: Callable[[str, Any],
Any], **kwargs) -> None:
"""Activate notifications/indications on a characteristic.
Callbacks must accept two inputs. The first will be a uuid string
object and the second will be a bytearray.
.. code-block:: python
def callback(sender, data):
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.
"""
if not isinstance(char_specifier, BleakGATTCharacteristic):
characteristic = self.services.get_characteristic(char_specifier)
else:
characteristic = char_specifier
if not characteristic:
raise BleakError(
"Characteristic {0} not found!".format(char_specifier))
if self._notification_callbacks.get(characteristic.handle):
await self.stop_notify(characteristic)
status = await self._start_notify(characteristic, callback)
if status != GattCommunicationStatus.Success:
# TODO: Find out how to get the ProtocolError code that describes a
# potential GattCommunicationStatus.ProtocolError result.
raise BleakError("Could not start notify on {0}: {1}".format(
characteristic.uuid, _communication_statues.get(status, "")))
async def _start_notify(
self,
characteristic: BleakGATTCharacteristic,
callback: Callable[[str, Any], Any],
):
"""Internal method performing call to BleakUWPBridge method.
Args:
characteristic: The BleakGATTCharacteristic to start notification on.
callback: The function to be called on notification.
Returns:
(int) The GattCommunicationStatus of the operation.
"""
characteristic_obj = characteristic.obj
if (characteristic_obj.CharacteristicProperties
& GattCharacteristicProperties.Indicate):
cccd = GattClientCharacteristicConfigurationDescriptorValue.Indicate
elif (characteristic_obj.CharacteristicProperties
& GattCharacteristicProperties.Notify):
cccd = GattClientCharacteristicConfigurationDescriptorValue.Notify
else:
cccd = getattr(
GattClientCharacteristicConfigurationDescriptorValue, "None")
try:
# TODO: Enable adding multiple handlers!
self._notification_callbacks[
characteristic.handle] = TypedEventHandler[
GattCharacteristic, GattValueChangedEventArgs](
_notification_wrapper(self.loop, callback))
self._bridge.AddValueChangedCallback(
characteristic_obj,
self._notification_callbacks[characteristic.handle])
except Exception as e:
logger.debug("Start Notify problem: {0}".format(e))
if characteristic_obj.Uuid.ToString(
) in self._notification_callbacks:
callback = self._notification_callbacks.pop(
characteristic.handle)
self._bridge.RemoveValueChangedCallback(
characteristic_obj, callback)
return GattCommunicationStatus.AccessDenied
status = await wrap_IAsyncOperation(
IAsyncOperation[GattCommunicationStatus](
characteristic_obj.
WriteClientCharacteristicConfigurationDescriptorAsync(cccd)),
return_type=GattCommunicationStatus,
loop=self.loop,
)
if status != GattCommunicationStatus.Success:
# This usually happens when a device reports that it support indicate,
# but it actually doesn't.
if characteristic.handle in self._notification_callbacks:
callback = self._notification_callbacks.pop(
characteristic.handle)
self._bridge.RemoveValueChangedCallback(
characteristic_obj, callback)
return GattCommunicationStatus.AccessDenied
return status
async def stop_notify(
self, char_specifier: Union[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.
"""
if not isinstance(char_specifier, BleakGATTCharacteristic):
characteristic = self.services.get_characteristic(char_specifier)
else:
characteristic = char_specifier
if not characteristic:
raise BleakError(
"Characteristic {} not found!".format(char_specifier))
status = await wrap_IAsyncOperation(
IAsyncOperation[GattCommunicationStatus](
characteristic.obj.
WriteClientCharacteristicConfigurationDescriptorAsync(
getattr(
GattClientCharacteristicConfigurationDescriptorValue,
"None"))),
return_type=GattCommunicationStatus,
loop=self.loop,
)
if status != GattCommunicationStatus.Success:
raise BleakError("Could not stop notify on {0}: {1}".format(
characteristic.uuid, _communication_statues.get(status, "")))
else:
callback = self._notification_callbacks.pop(characteristic.handle)
self._bridge.RemoveValueChangedCallback(characteristic.obj,
callback)
class BleakClientDotNet(BaseBleakClient):
"""The native Windows Bleak Client.
Implemented using `pythonnet <https://pythonnet.github.io/>`_, a package that provides an integration to the .NET
Common Language Runtime (CLR). Therefore, much of the code below has a distinct C# feel.
"""
def __init__(self, device, loop: AbstractEventLoop = None, **kwargs):
super(BleakClientDotNet, self).__init__(device, loop, **kwargs)
# Backend specific. Python.NET objects.
self._device_info = device.details
self._requester = None
self._bridge = Bridge()
self._callbacks = {}
def __str__(self):
return "BleakClientDotNet ({0})".format(self.address)
# Connectivity methods
async def connect(self) -> bool:
"""Connect to the specified GATT server.
Returns:
Boolean representing connection status.
"""
# Try to find the desired device.
# devices = await discover(2.0, loop=self.loop)
# sought_device = list(
# filter(lambda x: x.address.upper() == self.address.upper(), devices)
# )
#
# if len(sought_device):
# self._device_info = sought_device[0].details
# else:
# raise BleakError(
# "Device with address {0} was " "not found.".format(self.address)
# )
logger.debug("Connecting to BLE device @ {0}".format(self.address))
self._requester = await wrap_IAsyncOperation(
IAsyncOperation[BluetoothLEDevice](
BluetoothLEDevice.FromBluetoothAddressAsync(
UInt64(self._device_info.BluetoothAddress))),
return_type=BluetoothLEDevice,
loop=self.loop,
)
def _ConnectionStatusChanged_Handler(sender, args):
logger.debug("_ConnectionStatusChanged_Handler: " +
args.ToString())
self._requester.ConnectionStatusChanged += _ConnectionStatusChanged_Handler
# Obtain services, which also leads to connection being established.
await self.get_services()
await asyncio.sleep(0.2, loop=self.loop)
connected = await self.is_connected()
if connected:
logger.debug("Connection successful.")
else:
raise BleakError("Connection to {0} was not successful!".format(
self.address))
return connected
async def disconnect(self) -> bool:
"""Disconnect from the specified GATT server.
Returns:
Boolean representing connection status.
"""
logger.debug("Disconnecting from BLE device...")
# Remove notifications
# TODO: Make sure all notifications are removed prior to Dispose.
# Dispose all components that we have requested and created.
for service in self.services:
service.obj.Dispose()
self.services = BleakGATTServiceCollection()
self._requester.Dispose()
self._requester = None
return not await self.is_connected()
async def is_connected(self) -> bool:
"""Check connection status between this client and the server.
Returns:
Boolean representing connection status.
"""
if self._requester:
return (self._requester.ConnectionStatus ==
BluetoothConnectionStatus.Connected)
else:
return False
# GATT services methods
async def get_services(self) -> BleakGATTServiceCollection:
"""Get all services registered for this GATT server.
Returns:
A :py:class:`bleak.backends.service.BleakGATTServiceCollection` with this device's services tree.
"""
# Return the Service Collection.
if self._services_resolved:
return self.services
else:
logger.debug("Get Services...")
services_result = await wrap_IAsyncOperation(
IAsyncOperation[GattDeviceServicesResult](
self._requester.GetGattServicesAsync()),
return_type=GattDeviceServicesResult,
loop=self.loop,
)
if services_result.Status != GattCommunicationStatus.Success:
raise BleakDotNetTaskError("Could not get GATT services.")
# TODO: Check if fetching yeilds failures...
for service in services_result.Services:
characteristics_result = await wrap_IAsyncOperation(
IAsyncOperation[GattCharacteristicsResult](
service.GetCharacteristicsAsync()),
return_type=GattCharacteristicsResult,
loop=self.loop,
)
self.services.add_service(BleakGATTServiceDotNet(service))
if characteristics_result.Status != GattCommunicationStatus.Success:
raise BleakDotNetTaskError(
"Could not get GATT characteristics for {0}.".format(
service))
for characteristic in characteristics_result.Characteristics:
descriptors_result = await wrap_IAsyncOperation(
IAsyncOperation[GattDescriptorsResult](
characteristic.GetDescriptorsAsync()),
return_type=GattDescriptorsResult,
loop=self.loop,
)
self.services.add_characteristic(
BleakGATTCharacteristicDotNet(characteristic))
if descriptors_result.Status != GattCommunicationStatus.Success:
raise BleakDotNetTaskError(
"Could not get GATT descriptors for {0}.".format(
characteristic))
for descriptor in list(descriptors_result.Descriptors):
self.services.add_descriptor(
BleakGATTDescriptorDotNet(
descriptor, characteristic.Uuid.ToString()))
self._services_resolved = True
return self.services
# I/O methods
async def read_gatt_char(self,
_uuid: str,
use_cached=False,
**kwargs) -> bytearray:
"""Perform read operation on the specified GATT characteristic.
Args:
_uuid (str or UUID): The uuid of the characteristics to read from.
use_cached (bool): `False` forces Windows to read the value from the
device again and not use its own cached value. Defaults to `False`.
Returns:
(bytearray) The read data.
"""
characteristic = self.services.get_characteristic(str(_uuid))
if not characteristic:
raise BleakError("Characteristic {0} was not found!".format(_uuid))
read_result = await wrap_IAsyncOperation(
IAsyncOperation[GattReadResult](characteristic.obj.ReadValueAsync(
BluetoothCacheMode.
Cached if use_cached else BluetoothCacheMode.Uncached)),
return_type=GattReadResult,
loop=self.loop,
)
if read_result.Status == GattCommunicationStatus.Success:
reader = DataReader.FromBuffer(IBuffer(read_result.Value))
output = Array.CreateInstance(Byte, reader.UnconsumedBufferLength)
reader.ReadBytes(output)
value = bytearray(output)
logger.debug("Read Characteristic {0} : {1}".format(_uuid, value))
else:
raise BleakError(
"Could not read characteristic value for {0}: {1}".format(
characteristic.uuid, read_result.Status))
return value
async def read_gatt_descriptor(self,
handle: int,
use_cached=False,
**kwargs) -> bytearray:
"""Perform read operation on the specified GATT descriptor.
Args:
handle (int): The handle of the descriptor to read from.
use_cached (bool): `False` forces Windows to read the value from the
device again and not use its own cached value. Defaults to `False`.
Returns:
(bytearray) The read data.
"""
descriptor = self.services.get_descriptor(handle)
if not descriptor:
raise BleakError(
"Descriptor with handle {0} was not found!".format(handle))
read_result = await wrap_IAsyncOperation(
IAsyncOperation[GattReadResult](descriptor.obj.ReadValueAsync(
BluetoothCacheMode.
Cached if use_cached else BluetoothCacheMode.Uncached)),
return_type=GattReadResult,
loop=self.loop,
)
if read_result.Status == GattCommunicationStatus.Success:
reader = DataReader.FromBuffer(IBuffer(read_result.Value))
output = Array.CreateInstance(Byte, reader.UnconsumedBufferLength)
reader.ReadBytes(output)
value = bytearray(output)
logger.debug("Read Descriptor {0} : {1}".format(handle, value))
else:
raise BleakError(
"Could not read Descriptor value for {0}: {1}".format(
descriptor.uuid, read_result.Status))
return value
async def write_gatt_char(self,
_uuid: str,
data: bytearray,
response: bool = False) -> None:
"""Perform a write operation of the specified GATT characteristic.
Args:
_uuid (str or UUID): The uuid of the characteristics to write to.
data (bytes or bytearray): The data to send.
response (bool): If write-with-response operation should be done. Defaults to `False`.
"""
characteristic = self.services.get_characteristic(str(_uuid))
if not characteristic:
raise BleakError("Characteristic {0} was not found!".format(_uuid))
writer = DataWriter()
writer.WriteBytes(Array[Byte](data))
response = GattWriteOption.WriteWithResponse if response else GattWriteOption.WriteWithoutResponse
write_result = await wrap_IAsyncOperation(
IAsyncOperation[GattWriteResult](
characteristic.obj.WriteValueWithResultAsync(
writer.DetachBuffer(), response)),
return_type=GattWriteResult,
loop=self.loop,
)
if write_result.Status == GattCommunicationStatus.Success:
logger.debug("Write Characteristic {0} : {1}".format(_uuid, data))
else:
raise BleakError(
"Could not write value {0} to characteristic {1}: {2}".format(
data, characteristic.uuid, write_result.Status))
async def write_gatt_descriptor(self, handle: int,
data: bytearray) -> 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.
"""
descriptor = self.services.get_descriptor(handle)
if not descriptor:
raise BleakError("Descriptor {0} was not found!".format(handle))
writer = DataWriter()
writer.WriteBytes(Array[Byte](data))
write_result = await wrap_IAsyncOperation(
IAsyncOperation[GattWriteResult](descriptor.obj.WriteValueAsync(
writer.DetachBuffer())),
return_type=GattWriteResult,
loop=self.loop,
)
if write_result.Status == GattCommunicationStatus.Success:
logger.debug("Write Descriptor {0} : {1}".format(handle, data))
else:
raise BleakError(
"Could not write value {0} to descriptor {1}: {2}".format(
data, descriptor.uuid, write_result.Status))
async def start_notify(self, _uuid: str, callback: Callable[[str, Any],
Any],
**kwargs) -> None:
"""Activate notifications/indications on a characteristic.
Callbacks must accept two inputs. The first will be a uuid string
object and the second will be a bytearray.
.. code-block:: python
def callback(sender, data):
print(f"{sender}: {data}")
client.start_notify(char_uuid, callback)
Args:
_uuid (str or UUID): The uuid of the characteristics to start notification/indication on.
callback (function): The function to be called on notification.
"""
characteristic = self.services.get_characteristic(str(_uuid))
if self._notification_callbacks.get(str(_uuid)):
await self.stop_notify(_uuid)
status = await self._start_notify(characteristic.obj, callback)
if status != GattCommunicationStatus.Success:
raise BleakError("Could not start notify on {0}: {1}".format(
characteristic.uuid, status))
async def _start_notify(
self,
characteristic_obj: GattCharacteristic,
callback: Callable[[str, Any], Any],
):
"""Internal method performing call to BleakUWPBridge method.
Args:
characteristic_obj: The Managed Windows.Devices.Bluetooth.GenericAttributeProfile.GattCharacteristic Object
callback: The function to be called on notification.
Returns:
(int) The GattCommunicationStatus of the operation.
"""
if (characteristic_obj.CharacteristicProperties
& GattCharacteristicProperties.Indicate):
cccd = GattClientCharacteristicConfigurationDescriptorValue.Indicate
elif (characteristic_obj.CharacteristicProperties
& GattCharacteristicProperties.Notify):
cccd = GattClientCharacteristicConfigurationDescriptorValue.Notify
else:
cccd = getattr(
GattClientCharacteristicConfigurationDescriptorValue, "None")
try:
# TODO: Enable adding multiple handlers!
self._callbacks[characteristic_obj.Uuid.ToString(
)] = TypedEventHandler[GattCharacteristic,
GattValueChangedEventArgs](
_notification_wrapper(callback))
self._bridge.AddValueChangedCallback(
characteristic_obj,
self._callbacks[characteristic_obj.Uuid.ToString()])
except Exception as e:
logger.debug("Start Notify problem: {0}".format(e))
if characteristic_obj.Uuid.ToString() in self._callbacks:
callback = self._callbacks.pop(
characteristic_obj.Uuid.ToString())
self._bridge.RemoveValueChangedCallback(
characteristic_obj, callback)
return GattCommunicationStatus.AccessDenied
status = await wrap_IAsyncOperation(
IAsyncOperation[GattCommunicationStatus](
characteristic_obj.
WriteClientCharacteristicConfigurationDescriptorAsync(cccd)),
return_type=GattCommunicationStatus,
loop=self.loop,
)
if status != GattCommunicationStatus.Success:
# This usually happens when a device reports that it support indicate, but it actually doesn't.
if characteristic_obj.Uuid.ToString() in self._callbacks:
callback = self._callbacks.pop(
characteristic_obj.Uuid.ToString())
self._bridge.RemoveValueChangedCallback(
characteristic_obj, callback)
return GattCommunicationStatus.AccessDenied
return status
async def stop_notify(self, _uuid: str) -> None:
"""Deactivate notification/indication on a specified characteristic.
Args:
_uuid: The characteristic to stop notifying/indicating on.
"""
characteristic = self.services.get_characteristic(str(_uuid))
status = await wrap_IAsyncOperation(
IAsyncOperation[GattCommunicationStatus](
characteristic.obj.
WriteClientCharacteristicConfigurationDescriptorAsync(
getattr(
GattClientCharacteristicConfigurationDescriptorValue,
"None"))),
return_type=GattCommunicationStatus,
loop=self.loop,
)
if status != GattCommunicationStatus.Success:
raise BleakError("Could not start notify on {0}: {1}".format(
characteristic.uuid, status))
else:
callback = self._callbacks.pop(characteristic.uuid)
self._bridge.RemoveValueChangedCallback(characteristic.obj,
callback)