# SPDX-FileCopyrightText: 2018-2022 Espressif Systems (Shanghai) CO LTD # SPDX-License-Identifier: Apache-2.0 # import platform from utils import hex_str_to_bytes, str_to_bytes fallback = True # Check if required packages are installed # else fallback to console mode try: import bleak fallback = False except ImportError: pass # -------------------------------------------------------------------- def device_sort(device): return device.address class BLE_Bleak_Client: def __init__(self): self.adapter = None self.adapter_props = None self.characteristics = dict() self.chrc_names = None self.device = None self.devname = None self.iface = None self.nu_lookup = None self.services = None self.srv_uuid_adv = None self.srv_uuid_fallback = None async def connect(self, devname, iface, chrc_names, fallback_srv_uuid): self.devname = devname self.srv_uuid_fallback = fallback_srv_uuid self.chrc_names = [name.lower() for name in chrc_names] self.iface = iface print('Discovering...') try: devices = await bleak.discover() except bleak.exc.BleakDBusError as e: if str(e) == '[org.bluez.Error.NotReady] Resource Not Ready': raise RuntimeError('Bluetooth is not ready. Maybe try `bluetoothctl power on`?') raise found_device = None if self.devname is None: if len(devices) == 0: print('No devices found!') exit(1) while True: devices.sort(key=device_sort) print('==== BLE Discovery results ====') print('{0: >4} {1: <33} {2: <12}'.format( 'S.N.', 'Name', 'Address')) for i, _ in enumerate(devices): print('[{0: >2}] {1: <33} {2: <12}'.format(i + 1, devices[i].name or 'Unknown', devices[i].address)) while True: try: select = int(input('Select device by number (0 to rescan) : ')) if select < 0 or select > len(devices): raise ValueError break except ValueError: print('Invalid input! Retry') if select != 0: break devices = await bleak.discover() self.devname = devices[select - 1].name found_device = devices[select - 1] else: for d in devices: if d.name == self.devname: found_device = d if not found_device: raise RuntimeError('Device not found') uuids = found_device.metadata['uuids'] # There should be 1 service UUID in advertising data # If bluez had cached an old version of the advertisement data # the list of uuids may be incorrect, in which case connection # or service discovery may fail the first time. If that happens # the cache will be refreshed before next retry if len(uuids) == 1: self.srv_uuid_adv = uuids[0] print('Connecting...') self.device = bleak.BleakClient(found_device.address) await self.device.connect() # must be paired on Windows to access characteristics; # cannot be paired on Mac if platform.system() == 'Windows': await self.device.pair() print('Getting Services...') services = await self.device.get_services() service = services[self.srv_uuid_adv] or services[self.srv_uuid_fallback] if not service: await self.device.disconnect() self.device = None raise RuntimeError('Provisioning service not found') nu_lookup = dict() for characteristic in service.characteristics: for descriptor in characteristic.descriptors: if descriptor.uuid[4:8] != '2901': continue readval = await self.device.read_gatt_descriptor(descriptor.handle) found_name = ''.join(chr(b) for b in readval).lower() nu_lookup[found_name] = characteristic.uuid self.characteristics[characteristic.uuid] = characteristic match_found = True for name in self.chrc_names: if name not in nu_lookup: # Endpoint name not present match_found = False break # Create lookup table only if all endpoint names found self.nu_lookup = [None, nu_lookup][match_found] return True def get_nu_lookup(self): return self.nu_lookup def has_characteristic(self, uuid): print('checking for characteristic ' + uuid) if uuid in self.characteristics: return True return False async def disconnect(self): if self.device: print('Disconnecting...') if platform.system() == 'Windows': await self.device.unpair() await self.device.disconnect() self.device = None self.nu_lookup = None self.characteristics = dict() async def send_data(self, characteristic_uuid, data): await self.device.write_gatt_char(characteristic_uuid, bytearray(data.encode('latin-1')), True) readval = await self.device.read_gatt_char(characteristic_uuid) return ''.join(chr(b) for b in readval) # -------------------------------------------------------------------- # Console based BLE client for Cross Platform support class BLE_Console_Client: async def connect(self, devname, iface, chrc_names, fallback_srv_uuid): print('BLE client is running in console mode') print('\tThis could be due to your platform not being supported or dependencies not being met') print('\tPlease ensure all pre-requisites are met to run the full fledged client') print('BLECLI >> Please connect to BLE device `' + devname + '` manually using your tool of choice') resp = input('BLECLI >> Was the device connected successfully? [y/n] ') if resp != 'Y' and resp != 'y': return False print('BLECLI >> List available attributes of the connected device') resp = input("BLECLI >> Is the service UUID '" + fallback_srv_uuid + "' listed among available attributes? [y/n] ") if resp != 'Y' and resp != 'y': return False return True def get_nu_lookup(self): return None def has_characteristic(self, uuid): resp = input("BLECLI >> Is the characteristic UUID '" + uuid + "' listed among available attributes? [y/n] ") if resp != 'Y' and resp != 'y': return False return True async def disconnect(self): pass async def send_data(self, characteristic_uuid, data): print("BLECLI >> Write following data to characteristic with UUID '" + characteristic_uuid + "' :") print('\t>> ' + str_to_bytes(data).hex()) print('BLECLI >> Enter data read from characteristic (in hex) :') resp = input('\t<< ') return hex_str_to_bytes(resp) # -------------------------------------------------------------------- # Function to get client instance depending upon platform def get_client(): if fallback: return BLE_Console_Client() return BLE_Bleak_Client()