bleak.backends package

Subpackages

Submodules

bleak.backends.characteristic module

Interface class for the Bleak representation of a GATT Characteristic

Created on 2019-03-19 by hbldh <henrik.blidh@nedomkull.com>

class bleak.backends.characteristic.BleakGATTCharacteristic(obj: Any)[source]

Bases: abc.ABC

Interface for the Bleak representation of a GATT Characteristic

abstract add_descriptor(descriptor: bleak.backends.descriptor.BleakGATTDescriptor)[source]

Add a BleakGATTDescriptor to the characteristic.

Should not be used by end user, but rather by bleak itself.

property description: str

Description for this characteristic

abstract property descriptors: List

List of descriptors for this service

abstract get_descriptor(specifier: Union[int, str, uuid.UUID]) Optional[bleak.backends.descriptor.BleakGATTDescriptor][source]

Get a descriptor by handle (int) or UUID (str or uuid.UUID)

abstract property handle: int

The handle for this characteristic

abstract property properties: List[str]

Properties of this characteristic

abstract property service_handle: int

The integer handle of the Service containing this characteristic

abstract property service_uuid: str

The UUID of the Service containing this characteristic

abstract property uuid: str

The UUID for this characteristic

class bleak.backends.characteristic.GattCharacteristicsFlags(value)[source]

Bases: enum.Enum

An enumeration.

authenticated_signed_writes = 64
broadcast = 1
extended_properties = 128
indicate = 32
notify = 16
read = 2
reliable_write = 256
writable_auxiliaries = 512
write = 8
write_without_response = 4

bleak.backends.client module

Base class for backend clients.

Created on 2018-04-23 by hbldh <henrik.blidh@nedomkull.com>

class bleak.backends.client.BaseBleakClient(address_or_ble_device: Union[bleak.backends.device.BLEDevice, str], **kwargs)[source]

Bases: abc.ABC

The Client Interface for Bleak Backend implementations to implement.

The documentation of this interface should thus be safe to use as a reference for your implementation.

Parameters

address_or_ble_device (BLEDevice or str) – The Bluetooth address of the BLE peripheral to connect to or the BLEDevice object representing it.

Keyword Arguments
  • timeout (float) – Timeout for required discover call. Defaults to 10.0.

  • disconnected_callback (callable) – Callback that will be scheduled in the event loop when the client is disconnected. The callable must take one argument, which will be this client object.

abstract async connect(**kwargs) bool[source]

Connect to the specified GATT server.

Returns

Boolean representing connection status.

abstract async disconnect() bool[source]

Disconnect from the specified GATT server.

Returns

Boolean representing connection status.

abstract async get_services(**kwargs) bleak.backends.service.BleakGATTServiceCollection[source]

Get all services registered for this GATT server.

Returns

A bleak.backends.service.BleakGATTServiceCollection with this device’s services tree.

abstract property is_connected: bool

Check connection status between this client and the server.

Returns

Boolean representing connection status.

abstract async pair(*args, **kwargs) bool[source]

Pair with the peripheral.

abstract async read_gatt_char(char_specifier: Union[bleak.backends.characteristic.BleakGATTCharacteristic, int, str, uuid.UUID], **kwargs) bytearray[source]

Perform read operation on the specified GATT characteristic.

Parameters

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.

abstract async read_gatt_descriptor(handle: int, **kwargs) bytearray[source]

Perform read operation on the specified GATT descriptor.

Parameters

handle (int) – The handle of the descriptor to read from.

Returns

(bytearray) The read data.

set_disconnected_callback(callback: Optional[Callable[[bleak.backends.client.BaseBleakClient], None]], **kwargs) None[source]

Set the disconnect callback. The callback will only be called on unsolicited disconnect event.

Callbacks must accept one input which is the client object itself.

Set the callback to None to remove any existing callback.

def callback(client):
    print("Client with address {} got disconnected!".format(client.address))

client.set_disconnected_callback(callback)
client.connect()
Parameters

callback – callback to be called on disconnection.

abstract async start_notify(char_specifier: Union[bleak.backends.characteristic.BleakGATTCharacteristic, int, str, uuid.UUID], callback: Callable[[int, bytearray], None], **kwargs) None[source]

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.

def callback(sender: int, data: bytearray):
    print(f"{sender}: {data}")
client.start_notify(char_uuid, callback)
Parameters
  • 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.

abstract async stop_notify(char_specifier: Union[bleak.backends.characteristic.BleakGATTCharacteristic, int, str, uuid.UUID]) None[source]

Deactivate notification/indication on a specified characteristic.

Parameters

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.

abstract async unpair() bool[source]

Unpair with the peripheral.

abstract async write_gatt_char(char_specifier: Union[bleak.backends.characteristic.BleakGATTCharacteristic, int, str, uuid.UUID], data: Union[bytes, bytearray, memoryview], response: bool = False) None[source]

Perform a write operation on the specified GATT characteristic.

Parameters
  • 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.

abstract async write_gatt_descriptor(handle: int, data: Union[bytes, bytearray, memoryview]) None[source]

Perform a write operation on the specified GATT descriptor.

Parameters
  • handle (int) – The handle of the descriptor to read from.

  • data (bytes or bytearray) – The data to send.

bleak.backends.descriptor module

Interface class for the Bleak representation of a GATT Descriptor

Created on 2019-03-19 by hbldh <henrik.blidh@nedomkull.com>

class bleak.backends.descriptor.BleakGATTDescriptor(obj: Any)[source]

Bases: abc.ABC

Interface for the Bleak representation of a GATT Descriptor

abstract property characteristic_handle: int

handle for the characteristic that this descriptor belongs to

abstract property characteristic_uuid: str

UUID for the characteristic that this descriptor belongs to

property description: str

A text description of what this descriptor represents

abstract property handle: int

Integer handle for this descriptor

abstract property uuid: str

UUID for this descriptor

bleak.backends.device module

Wrapper class for Bluetooth LE servers returned from calling bleak.discover().

Created on 2018-04-23 by hbldh <henrik.blidh@nedomkull.com>

class bleak.backends.device.BLEDevice(address, name, details=None, rssi=0, **kwargs)[source]

Bases: object

A simple wrapper class representing a BLE server detected during a discover call.

  • When using Windows backend, details attribute is a Windows.Devices.Bluetooth.Advertisement.BluetoothLEAdvertisement object, unless it is created with the Windows.Devices.Enumeration discovery method, then is is a Windows.Devices.Enumeration.DeviceInformation.

  • When using Linux backend, details attribute is a dict with keys path which has the string path to the DBus device object and props which houses the properties dictionary of the D-Bus Device.

  • When using macOS backend, details attribute will be a CBPeripheral object.

address

The Bluetooth address of the device on this machine.

details

The OS native details required for connecting to the device.

metadata

Device specific details. Contains a uuids key which is a list of service UUIDs and a manufacturer_data field with a bytes-object from the advertised data.

name

The advertised name of the device.

rssi

RSSI, if available

bleak.backends.scanner module

class bleak.backends.scanner.AdvertisementData(**kwargs)[source]

Bases: object

Wrapper around the advertisement data that each platform returns upon discovery

class bleak.backends.scanner.BaseBleakScanner(detection_callback: Optional[Callable[[bleak.backends.device.BLEDevice, bleak.backends.scanner.AdvertisementData], Optional[Awaitable[None]]]], service_uuids: Optional[List[str]])[source]

Bases: abc.ABC

Interface for Bleak Bluetooth LE Scanners

Parameters
  • detection_callback – Optional function that will be called each time a device is discovered or advertising data has changed.

  • service_uuids – Optional list of service UUIDs to filter on. Only advertisements containing this advertising data will be received.

async classmethod discover(timeout=5.0, **kwargs) List[bleak.backends.device.BLEDevice][source]

Scan continuously for timeout seconds and return discovered devices.

Parameters

timeout – Time to scan for.

Keyword Arguments

**kwargs – Implementations might offer additional keyword arguments sent to the constructor of the BleakScanner class.

Returns:

abstract property discovered_devices: List[bleak.backends.device.BLEDevice]

Gets the devices registered by the BleakScanner.

Returns

A list of the devices that the scanner has discovered during the scanning.

async classmethod find_device_by_address(device_identifier: str, timeout: float = 10.0, **kwargs) Optional[bleak.backends.device.BLEDevice][source]

A convenience method for obtaining a BLEDevice object specified by Bluetooth address or (macOS) UUID address.

Parameters
  • device_identifier (str) – The Bluetooth/UUID address of the Bluetooth peripheral sought.

  • timeout (float) – Optional timeout to wait for detection of specified peripheral before giving up. Defaults to 10.0 seconds.

Keyword Arguments

adapter (str) – Bluetooth adapter to use for discovery.

Returns

The BLEDevice sought or None if not detected.

async classmethod find_device_by_filter(filterfunc: Callable[[bleak.backends.device.BLEDevice, bleak.backends.scanner.AdvertisementData], bool], timeout: float = 10.0, **kwargs) Optional[bleak.backends.device.BLEDevice][source]

A convenience method for obtaining a BLEDevice object specified by a filter function.

Parameters
  • filterfunc (AdvertisementDataFilter) – A function that is called for every BLEDevice found. It should return True only for the wanted device.

  • timeout (float) – Optional timeout to wait for detection of specified peripheral before giving up. Defaults to 10.0 seconds.

Keyword Arguments

adapter (str) – Bluetooth adapter to use for discovery.

Returns

The BLEDevice sought or None if not detected.

async get_discovered_devices() List[bleak.backends.device.BLEDevice][source]

Gets the devices registered by the BleakScanner.

Deprecated since version 0.11.0: This method will be removed in a future version of Bleak. Use the discovered_devices property instead.

Returns

A list of the devices that the scanner has discovered during the scanning.

register_detection_callback(callback: Optional[Callable[[bleak.backends.device.BLEDevice, bleak.backends.scanner.AdvertisementData], Optional[Awaitable[None]]]]) None[source]

Register a callback that is called when a device is discovered or has a property changed.

If another callback has already been registered, it will be replaced with callback. None can be used to remove the current callback.

The callback is a function or coroutine that takes two arguments: BLEDevice and AdvertisementData.

Parameters

callback – A function, coroutine or None.

abstract set_scanning_filter(**kwargs)[source]

Set scanning filter for the BleakScanner.

Parameters

**kwargs – The filter details. This will differ a lot between backend implementations.

abstract async start()[source]

Start scanning for devices

abstract async stop()[source]

Stop scanning for devices

bleak.backends.service module

Gatt Service Collection class and interface class for the Bleak representation of a GATT Service.

Created on 2019-03-19 by hbldh <henrik.blidh@nedomkull.com>

class bleak.backends.service.BleakGATTService(obj)[source]

Bases: abc.ABC

Interface for the Bleak representation of a GATT Service.

abstract add_characteristic(characteristic: bleak.backends.characteristic.BleakGATTCharacteristic)[source]

Add a BleakGATTCharacteristic to the service.

Should not be used by end user, but rather by bleak itself.

abstract property characteristics: List[bleak.backends.characteristic.BleakGATTCharacteristic]

List of characteristics for this service

property description: str

String description for this service

get_characteristic(uuid: Union[str, uuid.UUID]) Optional[bleak.backends.characteristic.BleakGATTCharacteristic][source]

Get a characteristic by UUID.

Parameters

uuid – The UUID to match.

Returns

The first characteristic matching uuid or None if no matching characteristic was found.

abstract property handle: int

The handle of this service

abstract property uuid: str

The UUID to this service

class bleak.backends.service.BleakGATTServiceCollection[source]

Bases: object

Simple data container for storing the peripheral’s service complement.

add_characteristic(characteristic: bleak.backends.characteristic.BleakGATTCharacteristic)[source]

Add a BleakGATTCharacteristic to the service collection.

Should not be used by end user, but rather by bleak itself.

add_descriptor(descriptor: bleak.backends.descriptor.BleakGATTDescriptor)[source]

Add a BleakGATTDescriptor to the service collection.

Should not be used by end user, but rather by bleak itself.

add_service(service: bleak.backends.service.BleakGATTService)[source]

Add a BleakGATTService to the service collection.

Should not be used by end user, but rather by bleak itself.

property characteristics: Dict[int, bleak.backends.characteristic.BleakGATTCharacteristic]

Returns dictionary of handles mapping to BleakGATTCharacteristic

property descriptors: Dict[int, bleak.backends.descriptor.BleakGATTDescriptor]

Returns a dictionary of integer handles mapping to BleakGATTDescriptor

get_characteristic(specifier: Union[int, str, uuid.UUID]) Optional[bleak.backends.characteristic.BleakGATTCharacteristic][source]

Get a characteristic by handle (int) or UUID (str or uuid.UUID)

get_descriptor(handle: int) Optional[bleak.backends.descriptor.BleakGATTDescriptor][source]

Get a descriptor by integer handle

get_service(specifier: Union[int, str, uuid.UUID]) Optional[bleak.backends.service.BleakGATTService][source]

Get a service by handle (int) or UUID (str or uuid.UUID)

property services: Dict[int, bleak.backends.service.BleakGATTService]

Returns dictionary of handles mapping to BleakGATTService

Module contents

__init__.py

Created on 2017-11-19 by hbldh <henrik.blidh@nedomkull.com>