Merge branch 'gbg/replace-bitstruct' of https://github.com/google/bumble into gbg/replace-bitstruct

# Conflicts:
#	bumble/a2dp.py
#	pyproject.toml

.git-blame-ignore-revs

@@ -0,0 +1,2 @@
+# Migrate code style to Black
+135df0dcc01ab765f432e19b1a5202d29bd55545

.github/workflows/code-check.yml

@@ -0,0 +1,35 @@
+# Check the code against the formatter and linter
+name: Code format and lint check
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+permissions:
+  contents: read
+
+jobs:
+  check:
+    name: Check Code
+    runs-on: ubuntu-latest
+
+    steps:
+    - name: Check out from Git
+      uses: actions/checkout@v3
+    - name: Get history and tags for SCM versioning to work
+      run: |
+        git fetch --prune --unshallow
+        git fetch --depth=1 origin +refs/tags/*:refs/tags/*
+    - name: Set up Python
+      uses: actions/setup-python@v3
+      with:
+        python-version: '3.10'
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        python -m pip install ".[build,test,development]"
+    - name: Check
+      run: |
+        invoke project.pre-commit

.gitignore

@@ -6,3 +6,6 @@ dist/
 docs/mkdocs/site
 test-results.xml
 __pycache__
+# generated by setuptools_scm
+bumble/_version.py
+.vscode/launch.json

.vscode/settings.json

@@ -0,0 +1,75 @@
+{
+    "cSpell.words": [
+        "Abortable",
+        "altsetting",
+        "ansiblue",
+        "ansicyan",
+        "ansigreen",
+        "ansimagenta",
+        "ansired",
+        "ansiyellow",
+        "appendleft",
+        "ASHA",
+        "asyncio",
+        "ATRAC",
+        "avdtp",
+        "bitpool",
+        "bitstruct",
+        "BSCP",
+        "BTPROTO",
+        "CCCD",
+        "cccds",
+        "cmac",
+        "CONNECTIONLESS",
+        "csrcs",
+        "datagram",
+        "DATALINK",
+        "delayreport",
+        "deregisters",
+        "deregistration",
+        "dhkey",
+        "diversifier",
+        "Fitbit",
+        "GATTLINK",
+        "HANDSFREE",
+        "keydown",
+        "keyup",
+        "levelname",
+        "libc",
+        "libusb",
+        "MITM",
+        "NDIS",
+        "NONBLOCK",
+        "NONCONN",
+        "OXIMETER",
+        "popleft",
+        "psms",
+        "pyee",
+        "pyusb",
+        "rfcomm",
+        "ROHC",
+        "rssi",
+        "SEID",
+        "seids",
+        "SERV",
+        "ssrc",
+        "strerror",
+        "subband",
+        "subbands",
+        "subevent",
+        "Subrating",
+        "substates",
+        "tobytes",
+        "tsep",
+        "usbmodem",
+        "vhci",
+        "websockets",
+        "xcursor",
+        "ycursor"
+    ],
+    "[python]": {
+        "editor.rulers": [88]
+    },
+    "python.formatting.provider": "black",
+    "pylint.importStrategy": "useBundled"
+}

LICENSE

@@ -199,4 +199,4 @@
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
-   limitations under the License.
+   limitations under the License.

README.md

@@ -15,10 +15,10 @@ Bumble is a full-featured Bluetooth stack written entirely in Python. It support
 
 ## Documentation
 
-Browse the pre-built [Online Documentation](https://google.github.io/bumble/), 
+Browse the pre-built [Online Documentation](https://google.github.io/bumble/),
 or see the documentation source under `docs/mkdocs/src`, or build the static HTML site from the markdown text with:
 ```
-mkdocs build -f docs/mkdocs/mkdocs.yml 
+mkdocs build -f docs/mkdocs/mkdocs.yml
 ```
 
 ## Usage
@@ -29,7 +29,7 @@ For a quick start to using Bumble, see the [Getting Started](docs/mkdocs/src/get
 
 ### Dependencies
 
-To install package dependencies needed to run the bumble examples execute the following commands:
+To install package dependencies needed to run the bumble examples, execute the following commands:
 
 ```
 python -m pip install --upgrade pip
@@ -50,7 +50,7 @@ Bumble is easiest to use with a dedicated USB dongle.
 This is because internal Bluetooth interfaces tend to be locked down by the operating system.
 You can use the [usb_probe](/docs/mkdocs/src/apps_and_tools/usb_probe.md) tool (all platforms) or `lsusb` (Linux or macOS) to list the available USB devices on your system.
 
-See the [USB Transport](/docs/mkdocs/src/transports/usb.md) page for details on how to refer to USB devices.
+See the [USB Transport](/docs/mkdocs/src/transports/usb.md) page for details on how to refer to USB devices. Also, if your are on a mac, see [these instructions](docs/mkdocs/src/platforms/macos.md).
 
 ## License
 

apps/README.md

@@ -47,5 +47,3 @@ NOTE: this assumes you're running a Link Relay on port `10723`.
 
 ## `console.py`
 A simple text-based-ui interactive Bluetooth device with GATT client capabilities.
-
-

apps/console.py

@@ -29,18 +29,6 @@ from collections import OrderedDict
 import click
 import colors
 
-from bumble.core import UUID, AdvertisingData, TimeoutError, BT_LE_TRANSPORT
-from bumble.device import ConnectionParametersPreferences, Device, Connection, Peer
-from bumble.utils import AsyncRunner
-from bumble.transport import open_transport_or_link
-from bumble.gatt import Characteristic
-from bumble.hci import (
-    HCI_Constant,
-    HCI_LE_1M_PHY,
-    HCI_LE_2M_PHY,
-    HCI_LE_CODED_PHY,
-)
-
 from prompt_toolkit import Application
 from prompt_toolkit.history import FileHistory
 from prompt_toolkit.completion import Completer, Completion, NestedCompleter
@@ -63,6 +51,21 @@ from prompt_toolkit.layout import (
     Dimension,
 )
 
+from bumble import __version__
+import bumble.core
+from bumble.core import UUID, AdvertisingData, BT_LE_TRANSPORT
+from bumble.device import ConnectionParametersPreferences, Device, Connection, Peer
+from bumble.utils import AsyncRunner
+from bumble.transport import open_transport_or_link
+from bumble.gatt import Characteristic, Service, CharacteristicDeclaration, Descriptor
+from bumble.hci import (
+    HCI_Constant,
+    HCI_LE_1M_PHY,
+    HCI_LE_2M_PHY,
+    HCI_LE_CODED_PHY,
+)
+
+
 # -----------------------------------------------------------------------------
 # Constants
 # -----------------------------------------------------------------------------
@@ -74,12 +77,6 @@ DISPLAY_MAX_RSSI = -30
 RSSI_MONITOR_INTERVAL = 5.0  # Seconds
 
 
-# -----------------------------------------------------------------------------
-# Globals
-# -----------------------------------------------------------------------------
-App = None
-
-
 # -----------------------------------------------------------------------------
 # Utils
 # -----------------------------------------------------------------------------
@@ -103,19 +100,19 @@ def rssi_bar(rssi):
 def parse_phys(phys):
     if phys.lower() == '*':
         return None
-    else:
+
-        phy_list = []
+    phy_list = []
-        elements = phys.lower().split(',')
+    elements = phys.lower().split(',')
-        for element in elements:
+    for element in elements:
-            if element == '1m':
+        if element == '1m':
-                phy_list.append(HCI_LE_1M_PHY)
+            phy_list.append(HCI_LE_1M_PHY)
-            elif element == '2m':
+        elif element == '2m':
-                phy_list.append(HCI_LE_2M_PHY)
+            phy_list.append(HCI_LE_2M_PHY)
-            elif element == 'coded':
+        elif element == 'coded':
-                phy_list.append(HCI_LE_CODED_PHY)
+            phy_list.append(HCI_LE_CODED_PHY)
-            else:
+        else:
-                raise ValueError('invalid PHY name')
+            raise ValueError('invalid PHY name')
-        return phy_list
+    return phy_list
 
 
 # -----------------------------------------------------------------------------
@@ -157,10 +154,10 @@ class ConsoleApp:
                     'rssi': {'on': None, 'off': None},
                     'show': {
                         'scan': None,
-                        'services': None,
-                        'attributes': None,
                         'log': None,
                         'device': None,
+                        'local-services': None,
+                        'remote-services': None,
                     },
                     'filter': {
                         'address': None,
@@ -200,8 +197,8 @@ class ConsoleApp:
         )
         self.output_max_lines = 20
         self.scan_results_text = FormattedTextControl()
-        self.services_text = FormattedTextControl()
+        self.local_services_text = FormattedTextControl()
-        self.attributes_text = FormattedTextControl()
+        self.remote_services_text = FormattedTextControl()
         self.device_text = FormattedTextControl()
         self.log_text = FormattedTextControl(
             get_cursor_position=lambda: Point(0, max(0, len(self.log_lines) - 1))
@@ -217,12 +214,12 @@ class ConsoleApp:
                     filter=Condition(lambda: self.top_tab == 'scan'),
                 ),
                 ConditionalContainer(
-                    Frame(Window(self.services_text), title='Services'),
+                    Frame(Window(self.local_services_text), title='Local Services'),
-                    filter=Condition(lambda: self.top_tab == 'services'),
+                    filter=Condition(lambda: self.top_tab == 'local-services'),
                 ),
                 ConditionalContainer(
-                    Frame(Window(self.attributes_text), title='Attributes'),
+                    Frame(Window(self.remote_services_text), title='Remove Services'),
-                    filter=Condition(lambda: self.top_tab == 'attributes'),
+                    filter=Condition(lambda: self.top_tab == 'remote-services'),
                 ),
                 ConditionalContainer(
                     Frame(Window(self.log_text, height=self.log_height), title='Log'),
@@ -251,15 +248,16 @@ class ConsoleApp:
 
         layout = Layout(container, focused_element=self.input_field)
 
-        kb = KeyBindings()
+        key_bindings = KeyBindings()
 
-        @kb.add("c-c")
+        @key_bindings.add("c-c")
-        @kb.add("c-q")
+        @key_bindings.add("c-q")
         def _(event):
             event.app.exit()
 
+        # pylint: disable=invalid-name
         self.ui = Application(
-            layout=layout, style=style, key_bindings=kb, full_screen=True
+            layout=layout, style=style, key_bindings=key_bindings, full_screen=True
         )
 
     async def run_async(self, device_config, transport):
@@ -274,8 +272,8 @@ class ConsoleApp:
                 random_address = (
                     f"{random.randint(192,255):02X}"  # address is static random
                 )
-                for c in random.sample(range(255), 5):
+                for random_byte in random.sample(range(255), 5):
-                    random_address += f":{c:02X}"
+                    random_address += f":{random_byte:02X}"
                 self.append_to_log(f"Setting random address: {random_address}")
                 self.device = Device.with_hci(
                     'Bumble', random_address, hci_source, hci_sink
@@ -283,6 +281,7 @@ class ConsoleApp:
             self.device.listener = DeviceListener(self)
             await self.device.power_on()
             self.show_device(self.device)
+            self.show_local_services(self.device.gatt_server.attributes)
 
             # Run the UI
             await self.ui.run_async()
@@ -292,7 +291,7 @@ class ConsoleApp:
     def add_known_address(self, address):
         self.known_addresses.add(address)
 
-    def accept_input(self, buff):
+    def accept_input(self, _):
         if len(self.input_field.text) == 0:
             return
         self.append_to_output([('', '* '), ('ansicyan', self.input_field.text)], False)
@@ -311,12 +310,24 @@ class ConsoleApp:
                 connection_state = 'CONNECTING'
             elif self.connected_peer:
                 connection = self.connected_peer.connection
-                connection_parameters = f'{connection.parameters.connection_interval}/{connection.parameters.peripheral_latency}/{connection.parameters.supervision_timeout}'
+                connection_parameters = (
+                    f'{connection.parameters.connection_interval}/'
+                    f'{connection.parameters.peripheral_latency}/'
+                    f'{connection.parameters.supervision_timeout}'
+                )
                 if connection.transport == BT_LE_TRANSPORT:
-                    phy_state = f' RX={le_phy_name(connection.phy.rx_phy)}/TX={le_phy_name(connection.phy.tx_phy)}'
+                    phy_state = (
+                        f' RX={le_phy_name(connection.phy.rx_phy)}/'
+                        f'TX={le_phy_name(connection.phy.tx_phy)}'
+                    )
                 else:
                     phy_state = ''
-                connection_state = f'{connection.peer_address} {connection_parameters} {connection.data_length}{phy_state}'
+                connection_state = (
+                    f'{connection.peer_address} '
+                    f'{connection_parameters} '
+                    f'{connection.data_length}'
+                    f'{phy_state}'
+                )
                 encryption_state = (
                     'ENCRYPTED' if connection.is_encrypted else 'NOT ENCRYPTED'
                 )
@@ -349,37 +360,45 @@ class ConsoleApp:
         self.scan_results_text.text = ANSI('\n'.join(lines))
         self.ui.invalidate()
 
-    def show_services(self, services):
+    def show_remote_services(self, services):
         lines = []
         del self.known_attributes[:]
         for service in services:
-            lines.append(('ansicyan', str(service) + '\n'))
+            lines.append(("ansicyan", f"{service}\n"))
 
             for characteristic in service.characteristics:
-                lines.append(('ansimagenta', '  ' + str(characteristic) + '\n'))
+                lines.append(('ansimagenta', f'  {characteristic} + \n'))
                 self.known_attributes.append(
                     f'{service.uuid.to_hex_str()}.{characteristic.uuid.to_hex_str()}'
                 )
                 self.known_attributes.append(f'*.{characteristic.uuid.to_hex_str()}')
                 self.known_attributes.append(f'#{characteristic.handle:X}')
                 for descriptor in characteristic.descriptors:
-                    lines.append(('ansigreen', '    ' + str(descriptor) + '\n'))
+                    lines.append(("ansigreen", f"    {descriptor}\n"))
 
-        self.services_text.text = lines
+        self.remote_services_text.text = lines
         self.ui.invalidate()
 
-    def show_attributes(self, attributes):
+    def show_local_services(self, attributes):
         lines = []
-
         for attribute in attributes:
-            lines.append(('ansicyan', f'{attribute}\n'))
+            if isinstance(attribute, Service):
+                lines.append(("ansicyan", f"{attribute}\n"))
+            elif isinstance(attribute, (Characteristic, CharacteristicDeclaration)):
+                lines.append(("ansimagenta", f"  {attribute}\n"))
+            elif isinstance(attribute, Descriptor):
+                lines.append(("ansigreen", f"    {attribute}\n"))
+            else:
+                lines.append(("ansiyellow", f"{attribute}\n"))
 
-        self.attributes_text.text = lines
+        self.local_services_text.text = lines
         self.ui.invalidate()
 
     def show_device(self, device):
         lines = []
 
+        lines.append(('ansicyan', 'Bumble Version:       '))
+        lines.append(('', f'{__version__}\n'))
         lines.append(('ansicyan', 'Name:                 '))
         lines.append(('', f'{device.name}\n'))
         lines.append(('ansicyan', 'Public Address:       '))
@@ -407,7 +426,10 @@ class ConsoleApp:
         advertising_interval = (
             device.advertising_interval_min
             if device.advertising_interval_min == device.advertising_interval_max
-            else f"{device.advertising_interval_min} to {device.advertising_interval_max}"
+            else (
+                f'{device.advertising_interval_min} to '
+                f'{device.advertising_interval_max}'
+            )
         )
         lines.append(('ansicyan', 'Advertising Interval: '))
         lines.append(('', f'{advertising_interval}\n'))
@@ -416,7 +438,7 @@ class ConsoleApp:
         self.ui.invalidate()
 
     def append_to_output(self, line, invalidate=True):
-        if type(line) is str:
+        if isinstance(line, str):
             line = [('', line)]
         self.output_lines = self.output_lines[-self.output_max_lines :]
         self.output_lines.append(line)
@@ -454,7 +476,7 @@ class ConsoleApp:
                 await self.connected_peer.discover_descriptors(characteristic)
         self.append_to_output('discovery completed')
 
-        self.show_services(self.connected_peer.services)
+        self.show_remote_services(self.connected_peer.services)
 
     async def discover_attributes(self):
         if not self.connected_peer:
@@ -486,6 +508,8 @@ class ConsoleApp:
                         if characteristic.handle == attribute_handle:
                             return characteristic
 
+        return None
+
     async def rssi_monitor_loop(self):
         while True:
             if self.monitor_rssi and self.connected_peer:
@@ -517,7 +541,8 @@ class ConsoleApp:
                 if not params[1].startswith("filter="):
                     self.show_error(
                         'invalid syntax',
-                        'expected address filter=key1:value1,key2:value,... available filters: address',
+                        'expected address filter=key1:value1,key2:value,... '
+                        'available filters: address',
                     )
                 # regex: (word):(any char except ,)
                 matches = re.findall(r"(\w+):([^,]+)", params[1])
@@ -575,10 +600,10 @@ class ConsoleApp:
                 timeout=DEFAULT_CONNECTION_TIMEOUT,
             )
             self.top_tab = 'services'
-        except TimeoutError:
+        except bumble.core.TimeoutError:
             self.show_error('connection timed out')
 
-    async def do_disconnect(self, params):
+    async def do_disconnect(self, _):
         if self.device.is_le_connecting:
             await self.device.cancel_connection()
         else:
@@ -592,7 +617,8 @@ class ConsoleApp:
         if len(params) != 1 or len(params[0].split('/')) != 3:
             self.show_error(
                 'invalid syntax',
-                'expected update-parameters <interval-min>-<interval-max>/<max-latency>/<supervision>',
+                'expected update-parameters <interval-min>-<interval-max>'
+                '/<max-latency>/<supervision>',
             )
             return
 
@@ -613,7 +639,7 @@ class ConsoleApp:
             supervision_timeout,
         )
 
-    async def do_encrypt(self, params):
+    async def do_encrypt(self, _):
         if not self.connected_peer:
             self.show_error('not connected')
             return
@@ -636,18 +662,25 @@ class ConsoleApp:
 
     async def do_show(self, params):
         if params:
-            if params[0] in {'scan', 'services', 'attributes', 'log', 'device'}:
+            if params[0] in {
+                'scan',
+                'log',
+                'device',
+                'local-services',
+                'remote-services',
+            }:
                 self.top_tab = params[0]
                 self.ui.invalidate()
 
-    async def do_get_phy(self, params):
+    async def do_get_phy(self, _):
         if not self.connected_peer:
             self.show_error('not connected')
             return
 
         phy = await self.connected_peer.connection.get_phy()
         self.append_to_output(
-            f'PHY: RX={HCI_Constant.le_phy_name(phy[0])}, TX={HCI_Constant.le_phy_name(phy[1])}'
+            f'PHY: RX={HCI_Constant.le_phy_name(phy[0])}, '
+            f'TX={HCI_Constant.le_phy_name(phy[1])}'
         )
 
     async def do_request_mtu(self, params):
@@ -790,10 +823,10 @@ class ConsoleApp:
             tx_phys=parse_phys(tx_phys), rx_phys=parse_phys(rx_phys)
         )
 
-    async def do_exit(self, params):
+    async def do_exit(self, _):
         self.ui.exit()
 
-    async def do_quit(self, params):
+    async def do_quit(self, _):
         self.ui.exit()
 
     async def do_filter(self, params):
@@ -824,7 +857,7 @@ class DeviceListener(Device.Listener, Connection.Listener):
         else:
             self._address_filter = re.compile(filter_addr)
         self.scan_results = OrderedDict(
-            filter(lambda x: self.filter_address_match(x), self.scan_results)
+            filter(self.filter_address_match, self.scan_results)
         )
         self.app.show_scan_results(self.scan_results)
 
@@ -835,6 +868,7 @@ class DeviceListener(Device.Listener, Connection.Listener):
         return bool(self.address_filter.match(address))
 
     @AsyncRunner.run_in_task()
+    # pylint: disable=invalid-overridden-method
     async def on_connection(self, connection):
         self.app.connected_peer = Peer(connection)
         self.app.connection_rssi = None
@@ -843,14 +877,16 @@ class DeviceListener(Device.Listener, Connection.Listener):
 
     def on_disconnection(self, reason):
         self.app.append_to_output(
-            f'disconnected from {self.app.connected_peer}, reason: {HCI_Constant.error_name(reason)}'
+            f'disconnected from {self.app.connected_peer}, '
+            f'reason: {HCI_Constant.error_name(reason)}'
         )
         self.app.connected_peer = None
         self.app.connection_rssi = None
 
     def on_connection_parameters_update(self):
         self.app.append_to_output(
-            f'connection parameters update: {self.app.connected_peer.connection.parameters}'
+            f'connection parameters update: '
+            f'{self.app.connected_peer.connection.parameters}'
         )
 
     def on_connection_phy_update(self):
@@ -864,13 +900,19 @@ class DeviceListener(Device.Listener, Connection.Listener):
         )
 
     def on_connection_encryption_change(self):
+        encryption_state = (
+            'encrypted'
+            if self.app.connected_peer.connection.is_encrypted
+            else 'not encrypted'
+        )
         self.app.append_to_output(
-            f'connection encryption change: {"encrypted" if self.app.connected_peer.connection.is_encrypted else "not encrypted"}'
+            'connection encryption change: ' f'{encryption_state}'
         )
 
     def on_connection_data_length_change(self):
         self.app.append_to_output(
-            f'connection data length change: {self.app.connected_peer.connection.data_length}'
+            'connection data length change: '
+            f'{self.app.connected_peer.connection.data_length}'
         )
 
     def on_advertisement(self, advertisement):
@@ -927,10 +969,16 @@ class ScanResult:
         else:
             name = ''
 
+        # Remove any '/P' qualifier suffix from the address string
+        address_str = str(self.address).replace('/P', '')
+
         # RSSI bar
         bar_string = rssi_bar(self.rssi)
         bar_padding = ' ' * (DEFAULT_RSSI_BAR_WIDTH + 5 - len(bar_string))
-        return f'{address_color(str(self.address))} [{type_color(address_type_string)}] {bar_string} {bar_padding} {name}'
+        return (
+            f'{address_color(address_str)} [{type_color(address_type_string)}] '
+            f'{bar_string} {bar_padding} {name}'
+        )
 
 
 # -----------------------------------------------------------------------------
@@ -958,7 +1006,7 @@ def main(device_config, transport):
     if not os.path.isdir(BUMBLE_USER_DIR):
         os.mkdir(BUMBLE_USER_DIR)
 
-    # Create an instane of the app
+    # Create an instance of the app
     app = ConsoleApp()
 
     # Setup logging
@@ -975,4 +1023,4 @@ def main(device_config, transport):
 
 # -----------------------------------------------------------------------------
 if __name__ == "__main__":
-    main()
+    main()  # pylint: disable=no-value-for-parameter

apps/controllers.py

@@ -29,12 +29,13 @@ from bumble.transport import open_transport_or_link
 async def async_main():
     if len(sys.argv) != 3:
         print(
-            'Usage: controllers.py <hci-transport-1> <hci-transport-2> [<hci-transport-3> ...]'
+            'Usage: controllers.py <hci-transport-1> <hci-transport-2> '
+            '[<hci-transport-3> ...]'
         )
         print('example: python controllers.py pty:ble1 pty:ble2')
         return
 
-    # Create a loccal link to attach the controllers to
+    # Create a local link to attach the controllers to
     link = LocalLink()
 
     # Create a transport and controller for all requested names

apps/gatt_dump.py

@@ -21,7 +21,7 @@ import logging
 import click
 from colors import color
 
-from bumble.core import ProtocolError, TimeoutError
+import bumble.core
 from bumble.device import Device, Peer
 from bumble.gatt import show_services
 from bumble.transport import open_transport_or_link
@@ -49,9 +49,9 @@ async def dump_gatt_db(peer, done):
         try:
             value = await attribute.read_value()
             print(color(f'{value.hex()}', 'green'))
-        except ProtocolError as error:
+        except bumble.core.ProtocolError as error:
             print(color(error, 'red'))
-        except TimeoutError:
+        except bumble.core.TimeoutError:
             print(color('read timeout', 'red'))
 
     if done is not None:

apps/gg_bridge.py

@@ -99,6 +99,7 @@ class GattlinkHubBridge(GattlinkL2capEndpoint, Device.Listener):
             print(color(f'!!! Connection failed: {error}', 'red'))
 
     @AsyncRunner.run_in_task()
+    # pylint: disable=invalid-overridden-method
     async def on_connection(self, connection):
         print(f'=== Connected to {connection}')
         self.peer = Peer(connection)
@@ -158,7 +159,8 @@ class GattlinkHubBridge(GattlinkL2capEndpoint, Device.Listener):
     def on_disconnection(self, reason):
         print(
             color(
-                f'!!! Disconnected from {self.peer}, reason={HCI_Constant.error_name(reason)}',
+                f'!!! Disconnected from {self.peer}, '
+                f'reason={HCI_Constant.error_name(reason)}',
                 'red',
             )
         )
@@ -189,7 +191,7 @@ class GattlinkHubBridge(GattlinkL2capEndpoint, Device.Listener):
         pass
 
     # Called by asyncio when a UDP datagram is received
-    def datagram_received(self, data, address):
+    def datagram_received(self, data, _address):
         print(color(f'<<< [UDP]: {len(data)} bytes', 'green'))
 
         if self.l2cap_channel:
@@ -209,6 +211,7 @@ class GattlinkNodeBridge(GattlinkL2capEndpoint, Device.Listener):
         self.tx_socket = None
         self.tx_subscriber = None
         self.rx_characteristic = None
+        self.transport = None
 
         # Register as a listener
         device.listener = self
@@ -264,7 +267,7 @@ class GattlinkNodeBridge(GattlinkL2capEndpoint, Device.Listener):
         self.transport = transport
 
     # Called by asyncio when a UDP datagram is received
-    def datagram_received(self, data, address):
+    def datagram_received(self, data, _address):
         print(color(f'<<< [UDP]: {len(data)} bytes', 'green'))
 
         if self.l2cap_channel:
@@ -276,7 +279,7 @@ class GattlinkNodeBridge(GattlinkL2capEndpoint, Device.Listener):
             asyncio.create_task(self.device.notify_subscribers(self.tx_characteristic))
 
     # Called when a write to the RX characteristic has been received
-    def on_rx_write(self, connection, data):
+    def on_rx_write(self, _connection, data):
         print(color(f'<<< [GATT RX]: {len(data)} bytes', 'cyan'))
         print(color('>>> [UDP]', 'magenta'))
         self.tx_socket.sendto(data)
@@ -284,7 +287,8 @@ class GattlinkNodeBridge(GattlinkL2capEndpoint, Device.Listener):
     # Called when the subscription to the TX characteristic has changed
     def on_tx_subscription(self, peer, enabled):
         print(
-            f'### [GATT TX] subscription from {peer}: {"enabled" if enabled else "disabled"}'
+            f'### [GATT TX] subscription from {peer}: '
+            f'{"enabled" if enabled else "disabled"}'
         )
         if enabled:
             self.tx_subscriber = peer
@@ -335,7 +339,9 @@ async def run(
 
         # Create a UDP to TX bridge (receive from TX, send to UDP)
         bridge.tx_socket, _ = await loop.create_datagram_endpoint(
-            lambda: asyncio.DatagramProtocol(), remote_addr=(send_host, send_port)
+            # pylint: disable-next=unnecessary-lambda
+            lambda: asyncio.DatagramProtocol(),
+            remote_addr=(send_host, send_port),
         )
 
         await device.power_on()

apps/hci_bridge.py

@@ -35,10 +35,13 @@ logger = logging.getLogger(__name__)
 async def async_main():
     if len(sys.argv) < 3:
         print(
-            'Usage: hci_bridge.py <host-transport-spec> <controller-transport-spec> [command-short-circuit-list]'
+            'Usage: hci_bridge.py <host-transport-spec> <controller-transport-spec> '
+            '[command-short-circuit-list]'
         )
         print(
-            'example: python hci_bridge.py udp:0.0.0.0:9000,127.0.0.1:9001 serial:/dev/tty.usbmodem0006839912171,1000000 0x3f:0x0070,0x3f:0x0074,0x3f:0x0077,0x3f:0x0078'
+            'example: python hci_bridge.py udp:0.0.0.0:9000,127.0.0.1:9001 '
+            'serial:/dev/tty.usbmodem0006839912171,1000000 '
+            '0x3f:0x0070,0x3f:0x0074,0x3f:0x0077,0x3f:0x0078'
         )
         return
 
@@ -82,6 +85,8 @@ async def async_main():
                     # Return a packet with 'respond to sender' set to True
                     return (response.to_bytes(), True)
 
+                return None
+
             _ = HCI_Bridge(
                 hci_host_source,
                 hci_host_sink,

apps/l2cap_bridge.py

@@ -16,9 +16,9 @@
 # Imports
 # -----------------------------------------------------------------------------
 import asyncio
-import click
 import logging
 import os
+import click
 from colors import color
 
 from bumble.transport import open_transport_or_link
@@ -89,7 +89,8 @@ class ServerBridge:
                 # Connect to the TCP server
                 print(
                     color(
-                        f'### Connecting to TCP {self.bridge.tcp_host}:{self.bridge.tcp_port}...',
+                        f'### Connecting to TCP {self.bridge.tcp_host}:'
+                        f'{self.bridge.tcp_port}...',
                         'yellow',
                     )
                 )
@@ -98,8 +99,8 @@ class ServerBridge:
                     def __init__(self, pipe):
                         self.pipe = pipe
 
-                    def connection_lost(self, error):
+                    def connection_lost(self, exc):
-                        print(color(f'!!! TCP connection lost: {error}', 'red'))
+                        print(color(f'!!! TCP connection lost: {exc}', 'red'))
                         if self.pipe.l2cap_channel is not None:
                             asyncio.create_task(self.pipe.l2cap_channel.disconnect())
 
@@ -178,8 +179,8 @@ class ClientBridge:
 
         # Called when a TCP connection is established
         async def on_tcp_connection(reader, writer):
-            peername = writer.get_extra_info('peername')
+            peer_name = writer.get_extra_info('peer_name')
-            print(color(f'<<< TCP connection from {peername}', 'magenta'))
+            print(color(f'<<< TCP connection from {peer_name}', 'magenta'))
 
             def on_coc_sdu(sdu):
                 print(color(f'<<< [L2CAP SDU]: {len(sdu)} bytes', 'cyan'))
@@ -346,4 +347,4 @@ def client(context, bluetooth_address, tcp_host, tcp_port):
 # -----------------------------------------------------------------------------
 logging.basicConfig(level=os.environ.get('BUMBLE_LOGLEVEL', 'WARNING').upper())
 if __name__ == '__main__':
-    cli(obj={})
+    cli(obj={})  # pylint: disable=no-value-for-parameter

apps/link_relay/link_relay.py

@@ -16,7 +16,6 @@
 # Imports
 # ----------------------------------------------------------------------------
 import sys
-import websockets
 import logging
 import json
 import asyncio
@@ -25,6 +24,7 @@ import uuid
 import os
 from urllib.parse import urlparse
 from colors import color
+import websockets
 
 # -----------------------------------------------------------------------------
 # Logging
@@ -98,7 +98,11 @@ class Connection:
         self.address = address
 
     def __str__(self):
-        return f'Connection(address="{self.address}", client={self.websocket.remote_address[0]}:{self.websocket.remote_address[1]})'
+        return (
+            f'Connection(address="{self.address}", '
+            f'client={self.websocket.remote_address[0]}:'
+            f'{self.websocket.remote_address[1]})'
+        )
 
 
 # ----------------------------------------------------------------------------
@@ -139,8 +143,8 @@ class Room:
 
             # Parse the message to decide how to handle it
             if message.startswith('@'):
-                # This is a targetted message
+                # This is a targeted message
-                await self.on_targetted_message(connection, message)
+                await self.on_targeted_message(connection, message)
             elif message.startswith('/'):
                 # This is an RPC request
                 await self.on_rpc_request(connection, message)
@@ -169,7 +173,7 @@ class Room:
 
         await connection.send_message(result or 'result:{}')
 
-    async def on_targetted_message(self, connection, message):
+    async def on_targeted_message(self, connection, message):
         target, *payload = message.split(' ', 1)
         if not payload:
             return error_to_json('missing arguments')
@@ -178,7 +182,8 @@ class Room:
 
         # Determine what targets to send to
         if target == '*':
-            # Send to all connections in the room except the connection from which the message was received
+            # Send to all connections in the room except the connection from which the
+            # message was received
             connections = [c for c in self.connections if c != connection]
         else:
             connections = self.find_connections_by_address(target)
@@ -216,9 +221,10 @@ class Relay:
     def start(self):
         logger.info(f'Starting Relay on port {self.port}')
 
+        # pylint: disable-next=no-member
         return websockets.serve(self.serve, '0.0.0.0', self.port, ping_interval=None)
 
-    async def serve_as_controller(connection):
+    async def serve_as_controller(self, connection):
         pass
 
     async def serve(self, websocket, path):
@@ -265,7 +271,7 @@ def main():
 
     # Setup logger
     if args.log_config:
-        from logging import config
+        from logging import config  # pylint: disable=import-outside-toplevel
 
         config.fileConfig(args.log_config)
     else:

apps/pair.py

@@ -86,15 +86,17 @@ class Delegate(PairingDelegate):
             while True:
                 response = await aioconsole.ainput(color('>>> Accept? ', 'yellow'))
                 response = response.lower().strip()
+
                 if response == 'yes':
                     return True
-                elif response == 'no':
-                    return False
-        else:
-            # Accept silently
-            return True
 
-    async def compare_numbers(self, number, digits):
+                if response == 'no':
+                    return False
+
+        # Accept silently
+        return True
+
+    async def compare_numbers(self, number, digits=6):
         await self.update_peer_name()
 
         # Wait a bit to allow some of the log lines to print before we prompt
@@ -111,9 +113,11 @@ class Delegate(PairingDelegate):
                 )
             )
             response = response.lower().strip()
+
             if response == 'yes':
                 return True
-            elif response == 'no':
+
+            if response == 'no':
                 return False
 
     async def get_number(self):
@@ -132,7 +136,7 @@ class Delegate(PairingDelegate):
             except ValueError:
                 pass
 
-    async def display_number(self, number, digits):
+    async def display_number(self, number, digits=6):
         await self.update_peer_name()
 
         # Wait a bit to allow some of the log lines to print before we prompt
@@ -149,17 +153,19 @@ class Delegate(PairingDelegate):
 async def get_peer_name(peer, mode):
     if mode == 'classic':
         return await peer.request_name()
-    else:
-        # Try to get the peer name from GATT
-        services = await peer.discover_service(GATT_GENERIC_ACCESS_SERVICE)
-        if not services:
-            return None
 
-        values = await peer.read_characteristics_by_uuid(
+    # Try to get the peer name from GATT
-            GATT_DEVICE_NAME_CHARACTERISTIC, services[0]
+    services = await peer.discover_service(GATT_GENERIC_ACCESS_SERVICE)
-        )
+    if not services:
-        if values:
+        return None
-            return values[0].decode('utf-8')
+
+    values = await peer.read_characteristics_by_uuid(
+        GATT_DEVICE_NAME_CHARACTERISTIC, services[0]
+    )
+    if values:
+        return values[0].decode('utf-8')
+
+    return None
 
 
 # -----------------------------------------------------------------------------
@@ -172,12 +178,12 @@ def read_with_error(connection):
 
     if AUTHENTICATION_ERROR_RETURNED[0]:
         return bytes([1])
-    else:
+
-        AUTHENTICATION_ERROR_RETURNED[0] = True
+    AUTHENTICATION_ERROR_RETURNED[0] = True
-        raise ATT_Error(ATT_INSUFFICIENT_AUTHENTICATION_ERROR)
+    raise ATT_Error(ATT_INSUFFICIENT_AUTHENTICATION_ERROR)
 
 
-def write_with_error(connection, value):
+def write_with_error(connection, _value):
     if not connection.is_encrypted:
         raise ATT_Error(ATT_INSUFFICIENT_ENCRYPTION_ERROR)
 

apps/scan.py

@@ -92,7 +92,8 @@ class AdvertisementPrinter:
 
         print(
             f'>>> {color(address, address_color)} '
-            f'[{color(address_type_string, type_color)}]{address_qualifier}{resolution_qualifier}:{separator}'
+            f'[{color(address_type_string, type_color)}]{address_qualifier}'
+            f'{resolution_qualifier}:{separator}'
             f'{phy_info}'
             f'RSSI:{advertisement.rssi:4} {rssi_bar}{separator}'
             f'{advertisement.data.to_string(separator)}\n'

apps/show.py

@@ -27,7 +27,8 @@ from bumble.helpers import PacketTracer
 # -----------------------------------------------------------------------------
 class SnoopPacketReader:
     '''
-    Reader that reads HCI packets from a "snoop" file (based on RFC 1761, but not exactly the same...)
+    Reader that reads HCI packets from a "snoop" file (based on RFC 1761, but not
+    exactly the same...)
     '''
 
     DATALINK_H1 = 1001
@@ -47,10 +48,7 @@ class SnoopPacketReader:
         (self.version_number, self.data_link_type) = struct.unpack(
             '>II', source.read(8)
         )
-        if (
+        if self.data_link_type not in (self.DATALINK_H4, self.DATALINK_H1):
-            self.data_link_type != self.DATALINK_H4
-            and self.data_link_type != self.DATALINK_H1
-        ):
             raise ValueError(f'datalink type {self.data_link_type} not supported')
 
     def next_packet(self):
@@ -62,9 +60,9 @@ class SnoopPacketReader:
             original_length,
             included_length,
             packet_flags,
-            cumulative_drops,
+            _cumulative_drops,
-            timestamp_seconds,
+            _timestamp_seconds,
-            timestamp_microsecond,
+            _timestamp_microsecond,
         ) = struct.unpack('>IIIIII', header)
 
         # Abort on truncated packets
@@ -90,8 +88,8 @@ class SnoopPacketReader:
                 packet_flags & 1,
                 bytes([packet_type]) + self.source.read(included_length),
             )
-        else:
+
-            return (packet_flags & 1, self.source.read(included_length))
+        return (packet_flags & 1, self.source.read(included_length))
 
 
 # -----------------------------------------------------------------------------
@@ -105,13 +103,14 @@ class SnoopPacketReader:
     help='Format of the input file',
 )
 @click.argument('filename')
+# pylint: disable=redefined-builtin
 def main(format, filename):
     input = open(filename, 'rb')
     if format == 'h4':
         packet_reader = PacketReader(input)
 
         def read_next_packet():
-            (0, packet_reader.next_packet())
+            return (0, packet_reader.next_packet())
 
     else:
         packet_reader = SnoopPacketReader(input)
@@ -128,9 +127,8 @@ def main(format, filename):
 
         except Exception as error:
             print(color(f'!!! {error}', 'red'))
-            pass
 
 
 # -----------------------------------------------------------------------------
 if __name__ == '__main__':
-    main()
+    main()  # pylint: disable=no-value-for-parameter

apps/usb_probe.py

@@ -28,11 +28,12 @@
 # -----------------------------------------------------------------------------
 import os
 import logging
-import sys
 import click
 import usb1
 from colors import color
 
+from bumble.transport.usb import load_libusb
+
 
 # -----------------------------------------------------------------------------
 # Constants
@@ -94,9 +95,9 @@ def show_device_details(device):
         print(f'  Configuration {configuration.getConfigurationValue()}')
         for interface in configuration:
             for setting in interface:
-                alternateSetting = setting.getAlternateSetting()
+                alternate_setting = setting.getAlternateSetting()
                 suffix = (
-                    f'/{alternateSetting}' if interface.getNumSettings() > 1 else ''
+                    f'/{alternate_setting}' if interface.getNumSettings() > 1 else ''
                 )
                 (class_string, subclass_string) = get_class_info(
                     setting.getClass(), setting.getSubClass(), setting.getProtocol()
@@ -111,7 +112,8 @@ def show_device_details(device):
                         else 'IN'
                     )
                     print(
-                        f'        Endpoint 0x{endpoint.getAddress():02X}: {endpoint_type} {endpoint_direction}'
+                        f'        Endpoint 0x{endpoint.getAddress():02X}: '
+                        f'{endpoint_type} {endpoint_direction}'
                     )
 
 
@@ -122,7 +124,7 @@ def get_class_info(cls, subclass, protocol):
     if class_info is None:
         class_string = f'0x{cls:02X}'
     else:
-        if type(class_info) is tuple:
+        if isinstance(class_info, tuple):
             class_string = class_info[0]
             subclass_info = class_info[1].get(subclass)
             if subclass_info:
@@ -169,6 +171,7 @@ def is_bluetooth_hci(device):
 def main(verbose):
     logging.basicConfig(level=os.environ.get('BUMBLE_LOGLEVEL', 'WARNING').upper())
 
+    load_libusb()
     with usb1.USBContext() as context:
         bluetooth_device_count = 0
         devices = {}
@@ -272,4 +275,4 @@ def main(verbose):
 
 # -----------------------------------------------------------------------------
 if __name__ == '__main__':
-    main()
+    main()  # pylint: disable=no-value-for-parameter

bumble/__init__.py

@@ -0,0 +1,4 @@
+try:
+    from ._version import version as __version__
+except ImportError:
+    __version__ = "unknown version"

bumble/a2dp.py

@@ -16,10 +16,9 @@
 # Imports
 # -----------------------------------------------------------------------------
 import struct
-import bitstruct
 import logging
 from collections import namedtuple
-from colors import color
+import construct
 
 from .company_ids import COMPANY_IDENTIFIERS
 from .sdp import (
@@ -134,14 +133,15 @@ MPEG_2_4_OBJECT_TYPE_NAMES = {
 # -----------------------------------------------------------------------------
 def flags_to_list(flags, values):
     result = []
-    for i in range(len(values)):
+    for i, value in enumerate(values):
         if flags & (1 << (len(values) - i - 1)):
-            result.append(values[i])
+            result.append(value)
     return result
 
 
 # -----------------------------------------------------------------------------
 def make_audio_source_service_sdp_records(service_record_handle, version=(1, 3)):
+    # pylint: disable=import-outside-toplevel
     from .avdtp import AVDTP_PSM
 
     version_int = version[0] << 8 | version[1]
@@ -191,6 +191,7 @@ def make_audio_source_service_sdp_records(service_record_handle, version=(1, 3))
 
 # -----------------------------------------------------------------------------
 def make_audio_sink_service_sdp_records(service_record_handle, version=(1, 3)):
+    # pylint: disable=import-outside-toplevel
     from .avdtp import AVDTP_PSM
 
     version_int = version[0] << 8 | version[1]
@@ -257,7 +258,17 @@ class SbcMediaCodecInformation(
     A2DP spec - 4.3.2 Codec Specific Information Elements
     '''
 
-    BIT_FIELDS = 'u4u4u4u2u2u8u8'
+    BIT_FIELDS = construct.Bitwise(
+        construct.Sequence(
+            construct.BitsInteger(4),
+            construct.BitsInteger(4),
+            construct.BitsInteger(4),
+            construct.BitsInteger(2),
+            construct.BitsInteger(2),
+            construct.BitsInteger(8),
+            construct.BitsInteger(8),
+        )
+    )
     SAMPLING_FREQUENCY_BITS = {16000: 1 << 3, 32000: 1 << 2, 44100: 1 << 1, 48000: 1}
     CHANNEL_MODE_BITS = {
         SBC_MONO_CHANNEL_MODE: 1 << 3,
@@ -275,7 +286,7 @@ class SbcMediaCodecInformation(
     @staticmethod
     def from_bytes(data):
         return SbcMediaCodecInformation(
-            *bitstruct.unpack(SbcMediaCodecInformation.BIT_FIELDS, data)
+            *SbcMediaCodecInformation.BIT_FIELDS.parse(data)
         )
 
     @classmethod
@@ -325,12 +336,13 @@ class SbcMediaCodecInformation(
         )
 
     def __bytes__(self):
-        return bitstruct.pack(self.BIT_FIELDS, *self)
+        return self.BIT_FIELDS.build(self)
 
     def __str__(self):
         channel_modes = ['MONO', 'DUAL_CHANNEL', 'STEREO', 'JOINT_STEREO']
         allocation_methods = ['SNR', 'Loudness']
         return '\n'.join(
+            # pylint: disable=line-too-long
             [
                 'SbcMediaCodecInformation(',
                 f'  sampling_frequency:    {",".join([str(x) for x in flags_to_list(self.sampling_frequency, SBC_SAMPLING_FREQUENCIES)])}',
@@ -348,14 +360,23 @@ class SbcMediaCodecInformation(
 class AacMediaCodecInformation(
     namedtuple(
         'AacMediaCodecInformation',
-        ['object_type', 'sampling_frequency', 'channels', 'vbr', 'bitrate'],
+        ['object_type', 'sampling_frequency', 'channels', 'rfa', 'vbr', 'bitrate'],
     )
 ):
     '''
     A2DP spec - 4.5.2 Codec Specific Information Elements
     '''
 
-    BIT_FIELDS = 'u8u12u2p2u1u23'
+    BIT_FIELDS = construct.Bitwise(
+        construct.Sequence(
+            construct.BitsInteger(8),
+            construct.BitsInteger(12),
+            construct.BitsInteger(2),
+            construct.BitsInteger(2),
+            construct.BitsInteger(1),
+            construct.BitsInteger(23),
+        )
+    )
     OBJECT_TYPE_BITS = {
         MPEG_2_AAC_LC_OBJECT_TYPE: 1 << 7,
         MPEG_4_AAC_LC_OBJECT_TYPE: 1 << 6,
@@ -381,7 +402,7 @@ class AacMediaCodecInformation(
     @staticmethod
     def from_bytes(data):
         return AacMediaCodecInformation(
-            *bitstruct.unpack(AacMediaCodecInformation.BIT_FIELDS, data)
+            *AacMediaCodecInformation.BIT_FIELDS.parse(data)
         )
 
     @classmethod
@@ -392,6 +413,7 @@ class AacMediaCodecInformation(
             object_type=cls.OBJECT_TYPE_BITS[object_type],
             sampling_frequency=cls.SAMPLING_FREQUENCY_BITS[sampling_frequency],
             channels=cls.CHANNELS_BITS[channels],
+            rfa=0,
             vbr=vbr,
             bitrate=bitrate,
         )
@@ -409,7 +431,7 @@ class AacMediaCodecInformation(
         )
 
     def __bytes__(self):
-        return bitstruct.pack(self.BIT_FIELDS, *self)
+        return self.BIT_FIELDS.build(self)
 
     def __str__(self):
         object_types = [
@@ -423,6 +445,7 @@ class AacMediaCodecInformation(
             '[7]',
         ]
         channels = [1, 2]
+        # pylint: disable=line-too-long
         return '\n'.join(
             [
                 'AacMediaCodecInformation(',
@@ -455,6 +478,7 @@ class VendorSpecificMediaCodecInformation:
         return struct.pack('<IH', self.vendor_id, self.codec_id, self.value)
 
     def __str__(self):
+        # pylint: disable=line-too-long
         return '\n'.join(
             [
                 'VendorSpecificMediaCodecInformation(',
@@ -489,7 +513,13 @@ class SbcFrame:
         return self.sample_count / self.sampling_frequency
 
     def __str__(self):
-        return f'SBC(sf={self.sampling_frequency},cm={self.channel_mode},br={self.bitrate},sc={self.sample_count},size={len(self.payload)})'
+        return (
+            f'SBC(sf={self.sampling_frequency},'
+            f'cm={self.channel_mode},'
+            f'br={self.bitrate},'
+            f'sc={self.sample_count},'
+            f'size={len(self.payload)})'
+        )
 
 
 # -----------------------------------------------------------------------------
@@ -551,6 +581,7 @@ class SbcPacketSource:
     @property
     def packets(self):
         async def generate_packets():
+            # pylint: disable=import-outside-toplevel
             from .avdtp import MediaPacket  # Import here to avoid a circular reference
 
             sequence_number = 0
@@ -582,7 +613,7 @@ class SbcPacketSource:
 
                     # Prepare for next packets
                     sequence_number += 1
-                    timestamp += sum([frame.sample_count for frame in frames])
+                    timestamp += sum((frame.sample_count for frame in frames))
                     frames = [frame]
                     frames_size = len(frame.payload)
                 else:

bumble/att.py

@@ -22,16 +22,21 @@
 # -----------------------------------------------------------------------------
 # Imports
 # -----------------------------------------------------------------------------
+from __future__ import annotations
+import struct
 from colors import color
 from pyee import EventEmitter
+from typing import Dict, Type
+
+from bumble.core import UUID, name_or_number
+from bumble.hci import HCI_Object, key_with_value
 
-from .core import *
-from .hci import *
 
 # -----------------------------------------------------------------------------
 # Constants
 # -----------------------------------------------------------------------------
 # fmt: off
+# pylint: disable=line-too-long
 
 ATT_CID = 0x04
 
@@ -165,21 +170,14 @@ ATT_ERROR_NAMES = {
 ATT_DEFAULT_MTU = 23
 
 HANDLE_FIELD_SPEC    = {'size': 2, 'mapper': lambda x: f'0x{x:04X}'}
-UUID_2_16_FIELD_SPEC = lambda x, y: UUID.parse_uuid(x, y)    # noqa: E731
+# pylint: disable-next=unnecessary-lambda-assignment,unnecessary-lambda
+UUID_2_16_FIELD_SPEC = lambda x, y: UUID.parse_uuid(x, y)
+# pylint: disable-next=unnecessary-lambda-assignment,unnecessary-lambda
 UUID_2_FIELD_SPEC    = lambda x, y: UUID.parse_uuid_2(x, y)  # noqa: E731
 
 # fmt: on
-
+# pylint: enable=line-too-long
-
+# pylint: disable=invalid-name
-# -----------------------------------------------------------------------------
-# Utils
-# -----------------------------------------------------------------------------
-def key_with_value(dictionary, target_value):
-    for key, value in dictionary.items():
-        if value == target_value:
-            return key
-    return None
-
 
 # -----------------------------------------------------------------------------
 # Exceptions
@@ -201,8 +199,9 @@ class ATT_PDU:
     See Bluetooth spec @ Vol 3, Part F - 3.3 ATTRIBUTE PDU
     '''
 
-    pdu_classes = {}
+    pdu_classes: Dict[int, Type[ATT_PDU]] = {}
     op_code = 0
+    name = None
 
     @staticmethod
     def from_bytes(pdu):
@@ -731,15 +730,15 @@ class Attribute(EventEmitter):
         self.permissions = permissions
 
         # Convert the type to a UUID object if it isn't already
-        if type(attribute_type) is str:
+        if isinstance(attribute_type, str):
             self.type = UUID(attribute_type)
-        elif type(attribute_type) is bytes:
+        elif isinstance(attribute_type, bytes):
             self.type = UUID.from_bytes(attribute_type)
         else:
             self.type = attribute_type
 
         # Convert the value to a byte array
-        if type(value) is str:
+        if isinstance(value, str):
             self.value = bytes(value, 'utf-8')
         else:
             self.value = value
@@ -753,9 +752,11 @@ class Attribute(EventEmitter):
     def read_value(self, connection):
         if read := getattr(self.value, 'read', None):
             try:
-                value = read(connection)
+                value = read(connection)  # pylint: disable=not-callable
             except ATT_Error as error:
-                raise ATT_Error(error_code=error.error_code, att_handle=self.handle)
+                raise ATT_Error(
+                    error_code=error.error_code, att_handle=self.handle
+                ) from error
         else:
             value = self.value
 
@@ -766,16 +767,18 @@ class Attribute(EventEmitter):
 
         if write := getattr(self.value, 'write', None):
             try:
-                write(connection, value)
+                write(connection, value)  # pylint: disable=not-callable
             except ATT_Error as error:
-                raise ATT_Error(error_code=error.error_code, att_handle=self.handle)
+                raise ATT_Error(
+                    error_code=error.error_code, att_handle=self.handle
+                ) from error
         else:
             self.value = value
 
         self.emit('write', connection, value)
 
     def __repr__(self):
-        if type(self.value) is bytes:
+        if isinstance(self.value, bytes):
             value_str = self.value.hex()
         else:
             value_str = str(self.value)
@@ -783,4 +786,8 @@ class Attribute(EventEmitter):
             value_string = f', value={self.value.hex()}'
         else:
             value_string = ''
-        return f'Attribute(handle=0x{self.handle:04X}, type={self.type}, permissions={self.permissions}{value_string})'
+        return (
+            f'Attribute(handle=0x{self.handle:04X}, '
+            f'type={self.type}, '
+            f'permissions={self.permissions}{value_string})'
+        )

bumble/avdtp.py

@@ -15,12 +15,14 @@
 # -----------------------------------------------------------------------------
 # Imports
 # -----------------------------------------------------------------------------
+from __future__ import annotations
 import asyncio
 import struct
 import time
 import logging
 from colors import color
 from pyee import EventEmitter
+from typing import Dict, Type
 
 from .core import (
     BT_ADVANCED_AUDIO_DISTRIBUTION_SERVICE,
@@ -49,6 +51,7 @@ logger = logging.getLogger(__name__)
 # Constants
 # -----------------------------------------------------------------------------
 # fmt: off
+# pylint: disable=line-too-long
 
 AVDTP_PSM = 0x0019
 
@@ -198,6 +201,8 @@ AVDTP_STATE_NAMES = {
 }
 
 # fmt: on
+# pylint: enable=line-too-long
+# pylint: disable=invalid-name
 
 
 # -----------------------------------------------------------------------------
@@ -318,7 +323,18 @@ class MediaPacket:
         return header + self.payload
 
     def __str__(self):
-        return f'RTP(v={self.version},p={self.padding},x={self.extension},m={self.marker},pt={self.payload_type},sn={self.sequence_number},ts={self.timestamp},ssrc={self.ssrc},csrcs={self.csrc_list},payload_size={len(self.payload)})'
+        return (
+            f'RTP(v={self.version},'
+            f'p={self.padding},'
+            f'x={self.extension},'
+            f'm={self.marker},'
+            f'pt={self.payload_type},'
+            f'sn={self.sequence_number},'
+            f'ts={self.timestamp},'
+            f'ssrc={self.ssrc},'
+            f'csrcs={self.csrc_list},'
+            f'payload_size={len(self.payload)})'
+        )
 
 
 # -----------------------------------------------------------------------------
@@ -369,7 +385,7 @@ class MediaPacketPump:
 
 
 # -----------------------------------------------------------------------------
-class MessageAssembler:
+class MessageAssembler:  # pylint: disable=attribute-defined-outside-init
     def __init__(self, callback):
         self.callback = callback
         self.reset()
@@ -390,16 +406,16 @@ class MessageAssembler:
         message_type = pdu[0] & 3
 
         logger.debug(
-            f'transaction_label={transaction_label}, packet_type={Protocol.packet_type_name(packet_type)}, message_type={Message.message_type_name(message_type)}'
+            f'transaction_label={transaction_label}, '
+            f'packet_type={Protocol.packet_type_name(packet_type)}, '
+            f'message_type={Message.message_type_name(message_type)}'
         )
-        if (
+        if packet_type in (Protocol.SINGLE_PACKET, Protocol.START_PACKET):
-            packet_type == Protocol.SINGLE_PACKET
-            or packet_type == Protocol.START_PACKET
-        ):
             if self.message is not None:
                 # The previous message has not been terminated
                 logger.warning(
-                    'received a start or single packet when expecting an end or continuation'
+                    'received a start or single packet when expecting an end or '
+                    'continuation'
                 )
                 self.reset()
 
@@ -413,23 +429,22 @@ class MessageAssembler:
             else:
                 self.number_of_signal_packets = pdu[2]
                 self.message = pdu[3:]
-        elif (
+        elif packet_type in (Protocol.CONTINUE_PACKET, Protocol.END_PACKET):
-            packet_type == Protocol.CONTINUE_PACKET
-            or packet_type == Protocol.END_PACKET
-        ):
             if self.packet_count == 0:
                 logger.warning('unexpected continuation')
                 return
 
             if transaction_label != self.transaction_label:
                 logger.warning(
-                    f'transaction label mismatch: expected {self.transaction_label}, received {transaction_label}'
+                    f'transaction label mismatch: expected {self.transaction_label}, '
+                    f'received {transaction_label}'
                 )
                 return
 
             if message_type != self.message_type:
                 logger.warning(
-                    f'message type mismatch: expected {self.message_type}, received {message_type}'
+                    f'message type mismatch: expected {self.message_type}, '
+                    f'received {message_type}'
                 )
                 return
 
@@ -438,7 +453,9 @@ class MessageAssembler:
             if packet_type == Protocol.END_PACKET:
                 if self.packet_count != self.number_of_signal_packets:
                     logger.warning(
-                        f'incomplete fragmented message: expected {self.number_of_signal_packets} packets, received {self.packet_count}'
+                        'incomplete fragmented message: '
+                        f'expected {self.number_of_signal_packets} packets, '
+                        f'received {self.packet_count}'
                     )
                     self.reset()
                     return
@@ -447,7 +464,9 @@ class MessageAssembler:
             else:
                 if self.packet_count > self.number_of_signal_packets:
                     logger.warning(
-                        f'too many packets: expected {self.number_of_signal_packets}, received {self.packet_count}'
+                        'too many packets: '
+                        f'expected {self.number_of_signal_packets}, '
+                        f'received {self.packet_count}'
                     )
                     self.reset()
                     return
@@ -515,7 +534,7 @@ class ServiceCapabilities:
         self.service_category = service_category
         self.service_capabilities_bytes = service_capabilities_bytes
 
-    def to_string(self, details=[]):
+    def to_string(self, details=[]):  # pylint: disable=dangerous-default-value
         attributes = ','.join(
             [name_or_number(AVDTP_SERVICE_CATEGORY_NAMES, self.service_category)]
             + details
@@ -562,10 +581,16 @@ class MediaCodecCapabilities(ServiceCapabilities):
         self.media_codec_information = media_codec_information
 
     def __str__(self):
+        codec_info = (
+            self.media_codec_information.hex()
+            if isinstance(self.media_codec_information, bytes)
+            else str(self.media_codec_information)
+        )
+
         details = [
             f'media_type={name_or_number(AVDTP_MEDIA_TYPE_NAMES, self.media_type)}',
             f'codec={name_or_number(A2DP_CODEC_TYPE_NAMES, self.media_codec_type)}',
-            f'codec_info={self.media_codec_information.hex() if type(self.media_codec_information) is bytes else str(self.media_codec_information)}',
+            f'codec_info={codec_info}',
         ]
         return self.to_string(details)
 
@@ -591,7 +616,7 @@ class EndPointInfo:
 
 
 # -----------------------------------------------------------------------------
-class Message:
+class Message:  # pylint:disable=attribute-defined-outside-init
     COMMAND = 0
     GENERAL_REJECT = 1
     RESPONSE_ACCEPT = 2
@@ -604,18 +629,19 @@ class Message:
         RESPONSE_REJECT: 'RESPONSE_REJECT',
     }
 
-    subclasses = {}  # Subclasses, by signal identifier and message type
+    # Subclasses, by signal identifier and message type
+    subclasses: Dict[int, Dict[int, Type[Message]]] = {}
 
     @staticmethod
     def message_type_name(message_type):
         return name_or_number(Message.MESSAGE_TYPE_NAMES, message_type)
 
     @staticmethod
-    def subclass(cls):
+    def subclass(subclass):
         # Infer the signal identifier and message subtype from the class name
-        name = cls.__name__
+        name = subclass.__name__
         if name == 'General_Reject':
-            cls.signal_identifier = 0
+            subclass.signal_identifier = 0
             signal_identifier_str = None
             message_type = Message.COMMAND
         elif name.endswith('_Command'):
@@ -630,22 +656,23 @@ class Message:
         else:
             raise ValueError('invalid class name')
 
-        cls.message_type = message_type
+        subclass.message_type = message_type
 
         if signal_identifier_str is not None:
             for (name, signal_identifier) in AVDTP_SIGNAL_IDENTIFIERS.items():
                 if name.lower().endswith(signal_identifier_str.lower()):
-                    cls.signal_identifier = signal_identifier
+                    subclass.signal_identifier = signal_identifier
                     break
 
             # Register the subclass
-            Message.subclasses.setdefault(cls.signal_identifier, {})[
+            Message.subclasses.setdefault(subclass.signal_identifier, {})[
-                cls.message_type
+                subclass.message_type
-            ] = cls
+            ] = subclass
 
-        return cls
+        return subclass
 
-    # Factory method to create a subclass based on the signal identifier and message type
+    # Factory method to create a subclass based on the signal identifier and message
+    # type
     @staticmethod
     def create(signal_identifier, message_type, payload):
         # Look for a registered subclass
@@ -676,18 +703,23 @@ class Message:
         self.payload = payload
 
     def to_string(self, details):
-        base = f'{color(f"{name_or_number(AVDTP_SIGNAL_NAMES, self.signal_identifier)}_{Message.message_type_name(self.message_type)}", "yellow")}'
+        base = color(
+            f'{name_or_number(AVDTP_SIGNAL_NAMES, self.signal_identifier)}_'
+            f'{Message.message_type_name(self.message_type)}',
+            'yellow',
+        )
+
         if details:
-            if type(details) is str:
+            if isinstance(details, str):
                 return f'{base}: {details}'
-            else:
+
-                return (
+            return (
-                    base
+                base
-                    + ':\n'
+                + ':\n'
-                    + '\n'.join(['  ' + color(detail, 'cyan') for detail in details])
+                + '\n'.join(['  ' + color(detail, 'cyan') for detail in details])
-                )
+            )
-        else:
+
-            return base
+        return base
 
     def __str__(self):
         return self.to_string(self.payload.hex())
@@ -703,8 +735,8 @@ class Simple_Command(Message):
         self.acp_seid = self.payload[0] >> 2
 
     def __init__(self, seid):
+        super().__init__(payload=bytes([seid << 2]))
         self.acp_seid = seid
-        self.payload = bytes([seid << 2])
 
     def __str__(self):
         return self.to_string([f'ACP SEID: {self.acp_seid}'])
@@ -720,8 +752,8 @@ class Simple_Reject(Message):
         self.error_code = self.payload[0]
 
     def __init__(self, error_code):
+        super().__init__(payload=bytes([error_code]))
         self.error_code = error_code
-        self.payload = bytes([self.error_code])
 
     def __str__(self):
         details = [f'error_code: {name_or_number(AVDTP_ERROR_NAMES, self.error_code)}']
@@ -752,13 +784,14 @@ class Discover_Response(Message):
             )
 
     def __init__(self, endpoints):
+        super().__init__(payload=b''.join([bytes(endpoint) for endpoint in endpoints]))
         self.endpoints = endpoints
-        self.payload = b''.join([bytes(endpoint) for endpoint in endpoints])
 
     def __str__(self):
         details = []
         for endpoint in self.endpoints:
             details.extend(
+                # pylint: disable=line-too-long
                 [
                     f'ACP SEID: {endpoint.seid}',
                     f'  in_use:     {endpoint.in_use}',
@@ -788,8 +821,10 @@ class Get_Capabilities_Response(Message):
         self.capabilities = ServiceCapabilities.parse_capabilities(self.payload)
 
     def __init__(self, capabilities):
+        super().__init__(
+            payload=ServiceCapabilities.serialize_capabilities(capabilities)
+        )
         self.capabilities = capabilities
-        self.payload = ServiceCapabilities.serialize_capabilities(capabilities)
 
     def __str__(self):
         details = [str(capability) for capability in self.capabilities]
@@ -841,12 +876,13 @@ class Set_Configuration_Command(Message):
         self.capabilities = ServiceCapabilities.parse_capabilities(self.payload[2:])
 
     def __init__(self, acp_seid, int_seid, capabilities):
+        super().__init__(
+            payload=bytes([acp_seid << 2, int_seid << 2])
+            + ServiceCapabilities.serialize_capabilities(capabilities)
+        )
         self.acp_seid = acp_seid
         self.int_seid = int_seid
         self.capabilities = capabilities
-        self.payload = bytes(
-            [acp_seid << 2, int_seid << 2]
-        ) + ServiceCapabilities.serialize_capabilities(capabilities)
 
     def __str__(self):
         details = [f'ACP SEID: {self.acp_seid}', f'INT SEID: {self.int_seid}'] + [
@@ -875,14 +911,20 @@ class Set_Configuration_Reject(Message):
         self.error_code = self.payload[1]
 
     def __init__(self, service_category, error_code):
+        super().__init__(payload=bytes([service_category, error_code]))
         self.service_category = service_category
         self.error_code = error_code
-        self.payload = bytes([service_category, self.error_code])
 
     def __str__(self):
         details = [
-            f'service_category: {name_or_number(AVDTP_SERVICE_CATEGORY_NAMES, self.service_category)}',
+            (
-            f'error_code:       {name_or_number(AVDTP_ERROR_NAMES, self.error_code)}',
+                'service_category: '
+                f'{name_or_number(AVDTP_SERVICE_CATEGORY_NAMES, self.service_category)}'
+            ),
+            (
+                'error_code:       '
+                f'{name_or_number(AVDTP_ERROR_NAMES, self.error_code)}'
+            ),
         ]
         return self.to_string(details)
 
@@ -906,8 +948,10 @@ class Get_Configuration_Response(Message):
         self.capabilities = ServiceCapabilities.parse_capabilities(self.payload)
 
     def __init__(self, capabilities):
+        super().__init__(
+            payload=ServiceCapabilities.serialize_capabilities(capabilities)
+        )
         self.capabilities = capabilities
-        self.payload = ServiceCapabilities.serialize_capabilities(capabilities)
 
     def __str__(self):
         details = [str(capability) for capability in self.capabilities]
@@ -930,6 +974,7 @@ class Reconfigure_Command(Message):
     '''
 
     def init_from_payload(self):
+        # pylint: disable=attribute-defined-outside-init
         self.acp_seid = self.payload[0] >> 2
         self.capabilities = ServiceCapabilities.parse_capabilities(self.payload[1:])
 
@@ -991,8 +1036,8 @@ class Start_Command(Message):
         self.acp_seids = [x >> 2 for x in self.payload]
 
     def __init__(self, seids):
+        super().__init__(payload=bytes([seid << 2 for seid in seids]))
         self.acp_seids = seids
-        self.payload = bytes([seid << 2 for seid in self.acp_seids])
 
     def __str__(self):
         return self.to_string([f'ACP SEIDs: {self.acp_seids}'])
@@ -1018,9 +1063,9 @@ class Start_Reject(Message):
         self.error_code = self.payload[1]
 
     def __init__(self, acp_seid, error_code):
+        super().__init__(payload=bytes([acp_seid << 2, error_code]))
         self.acp_seid = acp_seid
         self.error_code = error_code
-        self.payload = bytes([self.acp_seid << 2, self.error_code])
 
     def __str__(self):
         details = [
@@ -1126,7 +1171,7 @@ class General_Reject(Message):
     '''
 
     def to_string(self, details):
-        return f'{color(f"GENERAL_REJECT", "yellow")}'
+        return color('GENERAL_REJECT', 'yellow')
 
 
 # -----------------------------------------------------------------------------
@@ -1137,6 +1182,7 @@ class DelayReport_Command(Message):
     '''
 
     def init_from_payload(self):
+        # pylint: disable=attribute-defined-outside-init
         self.acp_seid = self.payload[0] >> 2
         self.delay = (self.payload[1] << 8) | (self.payload[2])
 
@@ -1206,9 +1252,11 @@ class Protocol:
         l2cap_channel.on('open', self.on_l2cap_channel_open)
 
     def get_local_endpoint_by_seid(self, seid):
-        if seid > 0 and seid <= len(self.local_endpoints):
+        if 0 < seid <= len(self.local_endpoints):
             return self.local_endpoints[seid - 1]
 
+        return None
+
     def add_source(self, codec_capabilities, packet_pump):
         seid = len(self.local_endpoints) + 1
         source = LocalSource(self, seid, codec_capabilities, packet_pump)
@@ -1288,12 +1336,15 @@ class Protocol:
                 if has_media_transport and has_codec:
                     return endpoint
 
+        return None
+
     def on_pdu(self, pdu):
         self.message_assembler.on_pdu(pdu)
 
     def on_message(self, transaction_label, message):
         logger.debug(
-            f'{color("<<< Received AVDTP message", "magenta")}: [{transaction_label}] {message}'
+            f'{color("<<< Received AVDTP message", "magenta")}: '
+            f'[{transaction_label}] {message}'
         )
 
         # Check that the identifier is not reserved
@@ -1311,7 +1362,12 @@ class Protocol:
 
         if message.message_type == Message.COMMAND:
             # Command
-            handler_name = f'on_{AVDTP_SIGNAL_NAMES.get(message.signal_identifier,"").replace("AVDTP_","").lower()}_command'
+            signal_name = (
+                AVDTP_SIGNAL_NAMES.get(message.signal_identifier, "")
+                .replace("AVDTP_", "")
+                .lower()
+            )
+            handler_name = f'on_{signal_name}_command'
             handler = getattr(self, handler_name, None)
             if handler:
                 try:
@@ -1344,7 +1400,8 @@ class Protocol:
 
     def send_message(self, transaction_label, message):
         logger.debug(
-            f'{color(">>> Sending AVDTP message", "magenta")}: [{transaction_label}] {message}'
+            f'{color(">>> Sending AVDTP message", "magenta")}: '
+            f'[{transaction_label}] {message}'
         )
         max_fragment_size = (
             self.l2cap_channel.mtu - 3
@@ -1398,10 +1455,7 @@ class Protocol:
         response = await transaction_result
 
         # Check for errors
-        if (
+        if response.message_type in (Message.GENERAL_REJECT, Message.RESPONSE_REJECT):
-            response.message_type == Message.GENERAL_REJECT
-            or response.message_type == Message.RESPONSE_REJECT
-        ):
             raise ProtocolError(response.error_code, 'avdtp')
 
         return response
@@ -1424,8 +1478,8 @@ class Protocol:
     async def get_capabilities(self, seid):
         if self.version > (1, 2):
             return await self.send_command(Get_All_Capabilities_Command(seid))
-        else:
+
-            return await self.send_command(Get_Capabilities_Command(seid))
+        return await self.send_command(Get_Capabilities_Command(seid))
 
     async def set_configuration(self, acp_seid, int_seid, capabilities):
         return await self.send_command(
@@ -1451,7 +1505,7 @@ class Protocol:
     async def abort(self, seid):
         return await self.send_command(Abort_Command(seid))
 
-    def on_discover_command(self, command):
+    def on_discover_command(self, _command):
         endpoint_infos = [
             EndPointInfo(endpoint.seid, 0, endpoint.media_type, endpoint.tsep)
             for endpoint in self.local_endpoints
@@ -1689,7 +1743,7 @@ class Stream:
         self.change_state(AVDTP_OPEN_STATE)
 
     async def close(self):
-        if self.state not in {AVDTP_OPEN_STATE, AVDTP_STREAMING_STATE}:
+        if self.state not in (AVDTP_OPEN_STATE, AVDTP_STREAMING_STATE):
             raise InvalidStateError('current state is not OPEN or STREAMING')
 
         logger.debug('closing local endpoint')
@@ -1718,13 +1772,14 @@ class Stream:
             return result
 
         self.change_state(AVDTP_CONFIGURED_STATE)
+        return None
 
     def on_get_configuration_command(self, configuration):
-        if self.state not in {
+        if self.state not in (
             AVDTP_CONFIGURED_STATE,
             AVDTP_OPEN_STATE,
             AVDTP_STREAMING_STATE,
-        }:
+        ):
             return Get_Configuration_Reject(AVDTP_BAD_STATE_ERROR)
 
         return self.local_endpoint.on_get_configuration_command(configuration)
@@ -1737,6 +1792,8 @@ class Stream:
         if result is not None:
             return result
 
+        return None
+
     def on_open_command(self):
         if self.state != AVDTP_CONFIGURED_STATE:
             return Open_Reject(AVDTP_BAD_STATE_ERROR)
@@ -1749,6 +1806,7 @@ class Stream:
         self.protocol.channel_acceptor = self
 
         self.change_state(AVDTP_OPEN_STATE)
+        return None
 
     def on_start_command(self):
         if self.state != AVDTP_OPEN_STATE:
@@ -1764,6 +1822,7 @@ class Stream:
             return result
 
         self.change_state(AVDTP_STREAMING_STATE)
+        return None
 
     def on_suspend_command(self):
         if self.state != AVDTP_STREAMING_STATE:
@@ -1774,9 +1833,10 @@ class Stream:
             return result
 
         self.change_state(AVDTP_OPEN_STATE)
+        return None
 
     def on_close_command(self):
-        if self.state not in {AVDTP_OPEN_STATE, AVDTP_STREAMING_STATE}:
+        if self.state not in (AVDTP_OPEN_STATE, AVDTP_STREAMING_STATE):
             return Open_Reject(AVDTP_BAD_STATE_ERROR)
 
         result = self.local_endpoint.on_close_command()
@@ -1792,6 +1852,8 @@ class Stream:
             # TODO: set a timer as we wait for the RTP channel to be closed
             pass
 
+        return None
+
     def on_abort_command(self):
         if self.rtp_channel is None:
             # No need to wait
@@ -1819,7 +1881,7 @@ class Stream:
         self.local_endpoint.in_use = 0
         self.rtp_channel = None
 
-        if self.state in {AVDTP_CLOSING_STATE, AVDTP_ABORTING_STATE}:
+        if self.state in (AVDTP_CLOSING_STATE, AVDTP_ABORTING_STATE):
             self.change_state(AVDTP_IDLE_STATE)
         else:
             logger.warning('unexpected channel close while not CLOSING or ABORTING')
@@ -1839,7 +1901,10 @@ class Stream:
         local_endpoint.in_use = 1
 
     def __str__(self):
-        return f'Stream({self.local_endpoint.seid} -> {self.remote_endpoint.seid} {self.state_name(self.state)})'
+        return (
+            f'Stream({self.local_endpoint.seid} -> '
+            f'{self.remote_endpoint.seid} {self.state_name(self.state)})'
+        )
 
 
 # -----------------------------------------------------------------------------
@@ -1852,12 +1917,14 @@ class StreamEndPoint:
         self.capabilities = capabilities
 
     def __str__(self):
+        media_type = f'{name_or_number(AVDTP_MEDIA_TYPE_NAMES, self.media_type)}'
+        tsep = f'{name_or_number(AVDTP_TSEP_NAMES, self.tsep)}'
         return '\n'.join(
             [
                 'SEP(',
                 f'  seid={self.seid}',
-                f'  media_type={name_or_number(AVDTP_MEDIA_TYPE_NAMES, self.media_type)}',
+                f'  media_type={media_type}',
-                f'  tsep={name_or_number(AVDTP_TSEP_NAMES, self.tsep)}',
+                f'  tsep={tsep}',
                 f'  in_use={self.in_use}',
                 '  capabilities=[',
                 '\n'.join([f'    {x}' for x in self.capabilities]),
@@ -1902,11 +1969,11 @@ class DiscoveredStreamEndPoint(StreamEndPoint, StreamEndPointProxy):
 # -----------------------------------------------------------------------------
 class LocalStreamEndPoint(StreamEndPoint):
     def __init__(
-        self, protocol, seid, media_type, tsep, capabilities, configuration=[]
+        self, protocol, seid, media_type, tsep, capabilities, configuration=None
     ):
         super().__init__(seid, media_type, tsep, 0, capabilities)
         self.protocol = protocol
-        self.configuration = configuration
+        self.configuration = configuration if configuration is not None else []
         self.stream = None
 
     async def start(self):
@@ -1968,14 +2035,14 @@ class LocalSource(LocalStreamEndPoint, EventEmitter):
     async def start(self):
         if self.packet_pump:
             return await self.packet_pump.start(self.stream.rtp_channel)
-        else:
+
-            self.emit('start', self.stream.rtp_channel)
+        self.emit('start', self.stream.rtp_channel)
 
     async def stop(self):
         if self.packet_pump:
             return await self.packet_pump.stop()
-        else:
+
-            self.emit('stop')
+        self.emit('stop')
 
     def on_set_configuration_command(self, configuration):
         # For now, blindly accept the configuration
@@ -2018,6 +2085,7 @@ class LocalSink(LocalStreamEndPoint, EventEmitter):
     def on_avdtp_packet(self, packet):
         rtp_packet = MediaPacket.from_bytes(packet)
         logger.debug(
-            f'{color("<<< RTP Packet:", "green")} {rtp_packet} {rtp_packet.payload[:16].hex()}'
+            f'{color("<<< RTP Packet:", "green")} '
+            f'{rtp_packet} {rtp_packet.payload[:16].hex()}'
         )
         self.emit('rtp_packet', rtp_packet)

bumble/company_ids.py

@@ -17,6 +17,7 @@
 #  the `generate_company_id_list.py` script
 # -----------------------------------------------------------------------------
 
+# pylint: disable=line-too-long
 COMPANY_IDENTIFIERS = {
     0x0000: "Ericsson Technology Licensing",
     0x0001: "Nokia Mobile Phones",
@@ -196,28 +197,28 @@ COMPANY_IDENTIFIERS = {
     0x00AF: "Cinetix",
     0x00B0: "Passif Semiconductor Corp",
     0x00B1: "Saris Cycling Group, Inc",
-    0x00B2: "​Bekey A/S",
+    0x00B2: "Bekey A/S",
-    0x00B3: "​Clarinox Technologies Pty. Ltd.",
+    0x00B3: "Clarinox Technologies Pty. Ltd.",
-    0x00B4: "​BDE Technology Co., Ltd.",
+    0x00B4: "BDE Technology Co., Ltd.",
     0x00B5: "Swirl Networks",
-    0x00B6: "​Meso international",
+    0x00B6: "Meso international",
-    0x00B7: "​TreLab Ltd",
+    0x00B7: "TreLab Ltd",
-    0x00B8: "​Qualcomm Innovation Center, Inc. (QuIC)",
+    0x00B8: "Qualcomm Innovation Center, Inc. (QuIC)",
-    0x00B9: "​​Johnson Controls, Inc.",
+    0x00B9: "Johnson Controls, Inc.",
-    0x00BA: "​Starkey Laboratories Inc.",
+    0x00BA: "Starkey Laboratories Inc.",
-    0x00BB: "​​S-Power Electronics Limited",
+    0x00BB: "S-Power Electronics Limited",
-    0x00BC: "​​Ace Sensor Inc",
+    0x00BC: "Ace Sensor Inc",
-    0x00BD: "​​Aplix Corporation",
+    0x00BD: "Aplix Corporation",
-    0x00BE: "​​AAMP of America",
+    0x00BE: "AAMP of America",
-    0x00BF: "​​Stalmart Technology Limited",
+    0x00BF: "Stalmart Technology Limited",
-    0x00C0: "​​AMICCOM Electronics Corporation",
+    0x00C0: "AMICCOM Electronics Corporation",
-    0x00C1: "​​Shenzhen Excelsecu Data Technology Co.,Ltd",
+    0x00C1: "Shenzhen Excelsecu Data Technology Co.,Ltd",
-    0x00C2: "​​Geneq Inc.",
+    0x00C2: "Geneq Inc.",
-    0x00C3: "​​adidas AG",
+    0x00C3: "adidas AG",
-    0x00C4: "​​LG Electronics​",
+    0x00C4: "LG Electronics",
-    0x00C5: "​Onset Computer Corporation",
+    0x00C5: "Onset Computer Corporation",
-    0x00C6: "​Selfly BV",
+    0x00C6: "Selfly BV",
-    0x00C7: "​Quuppa Oy.",
+    0x00C7: "Quuppa Oy.",
     0x00C8: "GeLo Inc",
     0x00C9: "Evluma",
     0x00CA: "MC10",
@@ -249,10 +250,10 @@ COMPANY_IDENTIFIERS = {
     0x00E4: "Laird Connectivity, Inc. formerly L.S. Research Inc.",
     0x00E5: "Eden Software Consultants Ltd.",
     0x00E6: "Freshtemp",
-    0x00E7: "​KS Technologies",
+    0x00E7: "KS Technologies",
-    0x00E8: "​ACTS Technologies",
+    0x00E8: "ACTS Technologies",
-    0x00E9: "​Vtrack Systems",
+    0x00E9: "Vtrack Systems",
-    0x00EA: "​Nielsen-Kellerman Company",
+    0x00EA: "Nielsen-Kellerman Company",
     0x00EB: "Server Technology Inc.",
     0x00EC: "BioResearch Associates",
     0x00ED: "Jolly Logic, LLC",

bumble/controller.py

@@ -19,9 +19,36 @@ import logging
 import asyncio
 import itertools
 import random
+import struct
+from colors import color
+from bumble.core import BT_CENTRAL_ROLE, BT_PERIPHERAL_ROLE
+
+from bumble.hci import (
+    HCI_ACL_DATA_PACKET,
+    HCI_COMMAND_DISALLOWED_ERROR,
+    HCI_COMMAND_PACKET,
+    HCI_COMMAND_STATUS_PENDING,
+    HCI_CONNECTION_TIMEOUT_ERROR,
+    HCI_EVENT_PACKET,
+    HCI_INVALID_HCI_COMMAND_PARAMETERS_ERROR,
+    HCI_LE_1M_PHY,
+    HCI_SUCCESS,
+    HCI_UNKNOWN_HCI_COMMAND_ERROR,
+    HCI_VERSION_BLUETOOTH_CORE_5_0,
+    Address,
+    HCI_AclDataPacket,
+    HCI_AclDataPacketAssembler,
+    HCI_Command_Complete_Event,
+    HCI_Command_Status_Event,
+    HCI_Disconnection_Complete_Event,
+    HCI_Encryption_Change_Event,
+    HCI_LE_Advertising_Report_Event,
+    HCI_LE_Connection_Complete_Event,
+    HCI_LE_Read_Remote_Features_Complete_Event,
+    HCI_Number_Of_Completed_Packets_Event,
+    HCI_Packet,
+)
 
-from .hci import *
-from .l2cap import *
 
 # -----------------------------------------------------------------------------
 # Logging
@@ -83,13 +110,19 @@ class Controller:
         self.manufacturer_name = 0xFFFF
         self.hc_le_data_packet_length = 27
         self.hc_total_num_le_data_packets = 64
+        self.event_mask = 0
+        self.event_mask_page_2 = 0
         self.supported_commands = bytes.fromhex(
-            '2000800000c000000000e40000002822000000000000040000f7ffff7f00000030f0f9ff01008004000000000000000000000000000000000000000000000000'
+            '2000800000c000000000e40000002822000000000000040000f7ffff7f000000'
+            '30f0f9ff01008004000000000000000000000000000000000000000000000000'
         )
+        self.le_event_mask = 0
+        self.advertising_parameters = None
         self.le_features = bytes.fromhex('ff49010000000000')
         self.le_states = bytes.fromhex('ffff3fffff030000')
         self.advertising_channel_tx_power = 0
         self.filter_accept_list_size = 8
+        self.filter_duplicates = False
         self.resolving_list_size = 8
         self.supported_max_tx_octets = 27
         self.supported_max_tx_time = 10000  # microseconds
@@ -133,7 +166,8 @@ class Controller:
     @host.setter
     def host(self, host):
         '''
-        Sets the host (sink) for this controller, and set this controller as the controller (sink) for the host
+        Sets the host (sink) for this controller, and set this controller as the
+        controller (sink) for the host
         '''
         self.set_packet_sink(host)
         if host:
@@ -151,7 +185,7 @@ class Controller:
 
     @public_address.setter
     def public_address(self, address):
-        if type(address) is str:
+        if isinstance(address, str):
             address = Address(address)
         self._public_address = address
 
@@ -161,7 +195,7 @@ class Controller:
 
     @random_address.setter
     def random_address(self, address):
-        if type(address) is str:
+        if isinstance(address, str):
             address = Address(address)
         self._random_address = address
         logger.debug(f'new random address: {address}')
@@ -175,7 +209,8 @@ class Controller:
 
     def on_hci_packet(self, packet):
         logger.debug(
-            f'{color("<<<", "blue")} [{self.name}] {color("HOST -> CONTROLLER", "blue")}: {packet}'
+            f'{color("<<<", "blue")} [{self.name}] '
+            f'{color("HOST -> CONTROLLER", "blue")}: {packet}'
         )
 
         # If the packet is a command, invoke the handler for this packet
@@ -192,7 +227,7 @@ class Controller:
         handler_name = f'on_{command.name.lower()}'
         handler = getattr(self, handler_name, self.on_hci_command)
         result = handler(command)
-        if type(result) is bytes:
+        if isinstance(result, bytes):
             self.send_hci_packet(
                 HCI_Command_Complete_Event(
                     num_hci_command_packets=1,
@@ -201,7 +236,7 @@ class Controller:
                 )
             )
 
-    def on_hci_event_packet(self, event):
+    def on_hci_event_packet(self, _event):
         logger.warning('!!! unexpected event packet')
 
     def on_hci_acl_data_packet(self, packet):
@@ -218,7 +253,8 @@ class Controller:
 
     def send_hci_packet(self, packet):
         logger.debug(
-            f'{color(">>>", "green")} [{self.name}] {color("CONTROLLER -> HOST", "green")}: {packet}'
+            f'{color(">>>", "green")} [{self.name}] '
+            f'{color("CONTROLLER -> HOST", "green")}: {packet}'
         )
         if self.host:
             self.host.on_packet(packet.to_bytes())
@@ -312,7 +348,7 @@ class Controller:
             # Remove the connection
             del self.peripheral_connections[peer_address]
         else:
-            logger.warn(f'!!! No peripheral connection found for {peer_address}')
+            logger.warning(f'!!! No peripheral connection found for {peer_address}')
 
     def on_link_peripheral_connection_complete(
         self, le_create_connection_command, status
@@ -339,6 +375,7 @@ class Controller:
 
         # Say that the connection has completed
         self.send_hci_packet(
+            # pylint: disable=line-too-long
             HCI_LE_Connection_Complete_Event(
                 status=status,
                 connection_handle=connection.handle if connection else 0,
@@ -391,9 +428,9 @@ class Controller:
             # Remove the connection
             del self.central_connections[peer_address]
         else:
-            logger.warn(f'!!! No central connection found for {peer_address}')
+            logger.warning(f'!!! No central connection found for {peer_address}')
 
-    def on_link_encrypted(self, peer_address, rand, ediv, ltk):
+    def on_link_encrypted(self, peer_address, _rand, _ediv, _ltk):
         # For now, just setup the encryption without asking the host
         if connection := self.find_connection_by_address(peer_address):
             self.send_hci_packet(
@@ -420,8 +457,8 @@ class Controller:
             return
 
         # Send a scan report
-        report = HCI_Object(
+        report = HCI_LE_Advertising_Report_Event.Report(
-            HCI_LE_Advertising_Report_Event.REPORT_FIELDS,
+            HCI_LE_Advertising_Report_Event.Report.FIELDS,
             event_type=HCI_LE_Advertising_Report_Event.ADV_IND,
             address_type=sender_address.address_type,
             address=sender_address,
@@ -431,8 +468,8 @@ class Controller:
         self.send_hci_packet(HCI_LE_Advertising_Report_Event([report]))
 
         # Simulate a scan response
-        report = HCI_Object(
+        report = HCI_LE_Advertising_Report_Event.Report(
-            HCI_LE_Advertising_Report_Event.REPORT_FIELDS,
+            HCI_LE_Advertising_Report_Event.Report.FIELDS,
             event_type=HCI_LE_Advertising_Report_Event.SCAN_RSP,
             address_type=sender_address.address_type,
             address=sender_address,
@@ -505,7 +542,7 @@ class Controller:
                 command.connection_handle
             )
         ):
-            logger.warn('connection not found')
+            logger.warning('connection not found')
             return
 
         if self.link:
@@ -521,7 +558,7 @@ class Controller:
         self.event_mask = command.event_mask
         return bytes([HCI_SUCCESS])
 
-    def on_hci_reset_command(self, command):
+    def on_hci_reset_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.3.2 Reset Command
         '''
@@ -543,7 +580,7 @@ class Controller:
                 pass
         return bytes([HCI_SUCCESS])
 
-    def on_hci_read_local_name_command(self, command):
+    def on_hci_read_local_name_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.3.12 Read Local Name Command
         '''
@@ -553,21 +590,22 @@ class Controller:
 
         return bytes([HCI_SUCCESS]) + local_name
 
-    def on_hci_read_class_of_device_command(self, command):
+    def on_hci_read_class_of_device_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.3.25 Read Class of Device Command
         '''
         return bytes([HCI_SUCCESS, 0, 0, 0])
 
-    def on_hci_write_class_of_device_command(self, command):
+    def on_hci_write_class_of_device_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.3.26 Write Class of Device Command
         '''
         return bytes([HCI_SUCCESS])
 
-    def on_hci_read_synchronous_flow_control_enable_command(self, command):
+    def on_hci_read_synchronous_flow_control_enable_command(self, _command):
         '''
-        See Bluetooth spec Vol 2, Part E - 7.3.36 Read Synchronous Flow Control Enable Command
+        See Bluetooth spec Vol 2, Part E - 7.3.36 Read Synchronous Flow Control Enable
+        Command
         '''
         if self.sync_flow_control:
             ret = 1
@@ -577,7 +615,8 @@ class Controller:
 
     def on_hci_write_synchronous_flow_control_enable_command(self, command):
         '''
-        See Bluetooth spec Vol 2, Part E - 7.3.37 Write Synchronous Flow Control Enable Command
+        See Bluetooth spec Vol 2, Part E - 7.3.37 Write Synchronous Flow Control Enable
+        Command
         '''
         ret = HCI_SUCCESS
         if command.synchronous_flow_control_enable == 1:
@@ -588,7 +627,7 @@ class Controller:
             ret = HCI_INVALID_HCI_COMMAND_PARAMETERS_ERROR
         return bytes([ret])
 
-    def on_hci_write_simple_pairing_mode_command(self, command):
+    def on_hci_write_simple_pairing_mode_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.3.59 Write Simple Pairing Mode Command
         '''
@@ -601,13 +640,13 @@ class Controller:
         self.event_mask_page_2 = command.event_mask_page_2
         return bytes([HCI_SUCCESS])
 
-    def on_hci_read_le_host_support_command(self, command):
+    def on_hci_read_le_host_support_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.3.78 Write LE Host Support Command
         '''
         return bytes([HCI_SUCCESS, 1, 0])
 
-    def on_hci_write_le_host_support_command(self, command):
+    def on_hci_write_le_host_support_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.3.79 Write LE Host Support Command
         '''
@@ -616,12 +655,13 @@ class Controller:
 
     def on_hci_write_authenticated_payload_timeout_command(self, command):
         '''
-        See Bluetooth spec Vol 2, Part E - 7.3.94 Write Authenticated Payload Timeout Command
+        See Bluetooth spec Vol 2, Part E - 7.3.94 Write Authenticated Payload Timeout
+        Command
         '''
         # TODO
         return struct.pack('<BH', HCI_SUCCESS, command.connection_handle)
 
-    def on_hci_read_local_version_information_command(self, command):
+    def on_hci_read_local_version_information_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.4.1 Read Local Version Information Command
         '''
@@ -635,19 +675,19 @@ class Controller:
             self.lmp_subversion,
         )
 
-    def on_hci_read_local_supported_commands_command(self, command):
+    def on_hci_read_local_supported_commands_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.4.2 Read Local Supported Commands Command
         '''
         return bytes([HCI_SUCCESS]) + self.supported_commands
 
-    def on_hci_read_local_supported_features_command(self, command):
+    def on_hci_read_local_supported_features_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.4.3 Read Local Supported Features Command
         '''
         return bytes([HCI_SUCCESS]) + self.lmp_features
 
-    def on_hci_read_bd_addr_command(self, command):
+    def on_hci_read_bd_addr_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.4.6 Read BD_ADDR Command
         '''
@@ -665,7 +705,7 @@ class Controller:
         self.le_event_mask = command.le_event_mask
         return bytes([HCI_SUCCESS])
 
-    def on_hci_le_read_buffer_size_command(self, command):
+    def on_hci_le_read_buffer_size_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.8.2 LE Read Buffer Size Command
         '''
@@ -676,9 +716,10 @@ class Controller:
             self.hc_total_num_le_data_packets,
         )
 
-    def on_hci_le_read_local_supported_features_command(self, command):
+    def on_hci_le_read_local_supported_features_command(self, _command):
         '''
-        See Bluetooth spec Vol 2, Part E - 7.8.3 LE Read Local Supported Features Command
+        See Bluetooth spec Vol 2, Part E - 7.8.3 LE Read Local Supported Features
+        Command
         '''
         return bytes([HCI_SUCCESS]) + self.le_features
 
@@ -696,9 +737,10 @@ class Controller:
         self.advertising_parameters = command
         return bytes([HCI_SUCCESS])
 
-    def on_hci_le_read_advertising_channel_tx_power_command(self, command):
+    def on_hci_le_read_advertising_physical_channel_tx_power_command(self, _command):
         '''
-        See Bluetooth spec Vol 2, Part E - 7.8.6 LE Read Advertising Channel Tx Power Command
+        See Bluetooth spec Vol 2, Part E - 7.8.6 LE Read Advertising Physical Channel
+        Tx Power Command
         '''
         return bytes([HCI_SUCCESS, self.advertising_channel_tx_power])
 
@@ -779,33 +821,36 @@ class Controller:
             )
         )
 
-    def on_hci_le_create_connection_cancel_command(self, command):
+    def on_hci_le_create_connection_cancel_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.8.13 LE Create Connection Cancel Command
         '''
         return bytes([HCI_SUCCESS])
 
-    def on_hci_le_read_filter_accept_list_size_command(self, command):
+    def on_hci_le_read_filter_accept_list_size_command(self, _command):
         '''
-        See Bluetooth spec Vol 2, Part E - 7.8.14 LE Read Filter Accept List Size Command
+        See Bluetooth spec Vol 2, Part E - 7.8.14 LE Read Filter Accept List Size
+        Command
         '''
         return bytes([HCI_SUCCESS, self.filter_accept_list_size])
 
-    def on_hci_le_clear_filter_accept_list_command(self, command):
+    def on_hci_le_clear_filter_accept_list_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.8.15 LE Clear Filter Accept List Command
         '''
         return bytes([HCI_SUCCESS])
 
-    def on_hci_le_add_device_to_filter_accept_list_command(self, command):
+    def on_hci_le_add_device_to_filter_accept_list_command(self, _command):
         '''
-        See Bluetooth spec Vol 2, Part E - 7.8.16 LE Add Device To Filter Accept List Command
+        See Bluetooth spec Vol 2, Part E - 7.8.16 LE Add Device To Filter Accept List
+        Command
         '''
         return bytes([HCI_SUCCESS])
 
-    def on_hci_le_remove_device_from_filter_accept_list_command(self, command):
+    def on_hci_le_remove_device_from_filter_accept_list_command(self, _command):
         '''
-        See Bluetooth spec Vol 2, Part E - 7.8.17 LE Remove Device From Filter Accept List Command
+        See Bluetooth spec Vol 2, Part E - 7.8.17 LE Remove Device From Filter Accept
+        List Command
         '''
         return bytes([HCI_SUCCESS])
 
@@ -832,7 +877,7 @@ class Controller:
             )
         )
 
-    def on_hci_le_rand_command(self, command):
+    def on_hci_le_rand_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.8.23 LE Rand Command
         '''
@@ -849,7 +894,7 @@ class Controller:
                 command.connection_handle
             )
         ):
-            logger.warn('connection not found')
+            logger.warning('connection not found')
             return bytes([HCI_INVALID_HCI_COMMAND_PARAMETERS_ERROR])
 
         # Notify that the connection is now encrypted
@@ -869,15 +914,18 @@ class Controller:
             )
         )
 
-    def on_hci_le_read_supported_states_command(self, command):
+        return None
+
+    def on_hci_le_read_supported_states_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.8.27 LE Read Supported States Command
         '''
         return bytes([HCI_SUCCESS]) + self.le_states
 
-    def on_hci_le_read_suggested_default_data_length_command(self, command):
+    def on_hci_le_read_suggested_default_data_length_command(self, _command):
         '''
-        See Bluetooth spec Vol 2, Part E - 7.8.34 LE Read Suggested Default Data Length Command
+        See Bluetooth spec Vol 2, Part E - 7.8.34 LE Read Suggested Default Data Length
+        Command
         '''
         return struct.pack(
             '<BHH',
@@ -888,33 +936,35 @@ class Controller:
 
     def on_hci_le_write_suggested_default_data_length_command(self, command):
         '''
-        See Bluetooth spec Vol 2, Part E - 7.8.35 LE Write Suggested Default Data Length Command
+        See Bluetooth spec Vol 2, Part E - 7.8.35 LE Write Suggested Default Data Length
+        Command
         '''
         self.suggested_max_tx_octets, self.suggested_max_tx_time = struct.unpack(
             '<HH', command.parameters[:4]
         )
         return bytes([HCI_SUCCESS])
 
-    def on_hci_le_read_local_p_256_public_key_command(self, command):
+    def on_hci_le_read_local_p_256_public_key_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.8.36 LE Read P-256 Public Key Command
         '''
         # TODO create key and send HCI_LE_Read_Local_P-256_Public_Key_Complete event
         return bytes([HCI_SUCCESS])
 
-    def on_hci_le_add_device_to_resolving_list_command(self, command):
+    def on_hci_le_add_device_to_resolving_list_command(self, _command):
         '''
-        See Bluetooth spec Vol 2, Part E - 7.8.38 LE Add Device To Resolving List Command
+        See Bluetooth spec Vol 2, Part E - 7.8.38 LE Add Device To Resolving List
+        Command
         '''
         return bytes([HCI_SUCCESS])
 
-    def on_hci_le_clear_resolving_list_command(self, command):
+    def on_hci_le_clear_resolving_list_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.8.40 LE Clear Resolving List Command
         '''
         return bytes([HCI_SUCCESS])
 
-    def on_hci_le_read_resolving_list_size_command(self, command):
+    def on_hci_le_read_resolving_list_size_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.8.41 LE Read Resolving List Size Command
         '''
@@ -922,7 +972,8 @@ class Controller:
 
     def on_hci_le_set_address_resolution_enable_command(self, command):
         '''
-        See Bluetooth spec Vol 2, Part E - 7.8.44 LE Set Address Resolution Enable Command
+        See Bluetooth spec Vol 2, Part E - 7.8.44 LE Set Address Resolution Enable
+        Command
         '''
         ret = HCI_SUCCESS
         if command.address_resolution_enable == 1:
@@ -935,12 +986,13 @@ class Controller:
 
     def on_hci_le_set_resolvable_private_address_timeout_command(self, command):
         '''
-        See Bluetooth spec Vol 2, Part E - 7.8.45 LE Set Resolvable Private Address Timeout Command
+        See Bluetooth spec Vol 2, Part E - 7.8.45 LE Set Resolvable Private Address
+        Timeout Command
         '''
         self.le_rpa_timeout = command.rpa_timeout
         return bytes([HCI_SUCCESS])
 
-    def on_hci_le_read_maximum_data_length_command(self, command):
+    def on_hci_le_read_maximum_data_length_command(self, _command):
         '''
         See Bluetooth spec Vol 2, Part E - 7.8.46 LE Read Maximum Data Length Command
         '''
@@ -955,7 +1007,7 @@ class Controller:
 
     def on_hci_le_read_phy_command(self, command):
         '''
-        See Bluetooth spec Vol 2, Part E - 7.8.47 LE Read PHY command
+        See Bluetooth spec Vol 2, Part E - 7.8.47 LE Read PHY Command
         '''
         return struct.pack(
             '<BHBB',
@@ -975,3 +1027,9 @@ class Controller:
             'rx_phys': command.rx_phys,
         }
         return bytes([HCI_SUCCESS])
+
+    def on_hci_le_read_transmit_power_command(self, _command):
+        '''
+        See Bluetooth spec Vol 2, Part E - 7.8.74 LE Read Transmit Power Command
+        '''
+        return struct.pack('<BBB', HCI_SUCCESS, 0, 0)

bumble/core.py

@@ -15,7 +15,9 @@
 # -----------------------------------------------------------------------------
 # Imports
 # -----------------------------------------------------------------------------
+from __future__ import annotations
 import struct
+from typing import List, Optional, Tuple, Union, cast
 
 from .company_ids import COMPANY_IDENTIFIERS
 
@@ -100,7 +102,7 @@ class ProtocolError(BaseError):
     """Protocol Error"""
 
 
-class TimeoutError(Exception):
+class TimeoutError(Exception):  # pylint: disable=redefined-builtin
     """Timeout Error"""
 
 
@@ -112,7 +114,7 @@ class InvalidStateError(Exception):
     """Invalid State Error"""
 
 
-class ConnectionError(BaseError):
+class ConnectionError(BaseError):  # pylint: disable=redefined-builtin
     """Connection Error"""
 
     FAILURE = 0x01
@@ -145,10 +147,10 @@ class UUID:
     '''
 
     BASE_UUID = bytes.fromhex('00001000800000805F9B34FB')
-    UUIDS = []  # Registry of all instances created
+    UUIDS: List[UUID] = []  # Registry of all instances created
 
     def __init__(self, uuid_str_or_int, name=None):
-        if type(uuid_str_or_int) is int:
+        if isinstance(uuid_str_or_int, int):
             self.uuid_bytes = struct.pack('<H', uuid_str_or_int)
         else:
             if len(uuid_str_or_int) == 36:
@@ -168,7 +170,8 @@ class UUID:
         self.name = name
 
     def register(self):
-        # Register this object in the class registry, and update the entry's name if it wasn't set already
+        # Register this object in the class registry, and update the entry's name if
+        # it wasn't set already
         for uuid in self.UUIDS:
             if self == uuid:
                 if uuid.name is None:
@@ -179,15 +182,15 @@ class UUID:
         return self
 
     @classmethod
-    def from_bytes(cls, uuid_bytes, name=None):
+    def from_bytes(cls, uuid_bytes: bytes, name: Optional[str] = None) -> UUID:
-        if len(uuid_bytes) in {2, 4, 16}:
+        if len(uuid_bytes) in (2, 4, 16):
             self = cls.__new__(cls)
             self.uuid_bytes = uuid_bytes
             self.name = name
 
             return self.register()
-        else:
+
-            raise ValueError('only 2, 4 and 16 bytes are allowed')
+        raise ValueError('only 2, 4 and 16 bytes are allowed')
 
     @classmethod
     def from_16_bits(cls, uuid_16, name=None):
@@ -198,20 +201,21 @@ class UUID:
         return cls.from_bytes(struct.pack('<I', uuid_32), name)
 
     @classmethod
-    def parse_uuid(cls, bytes, offset):
+    def parse_uuid(cls, uuid_as_bytes, offset):
-        return len(bytes), cls.from_bytes(bytes[offset:])
+        return len(uuid_as_bytes), cls.from_bytes(uuid_as_bytes[offset:])
 
     @classmethod
-    def parse_uuid_2(cls, bytes, offset):
+    def parse_uuid_2(cls, uuid_as_bytes, offset):
-        return offset + 2, cls.from_bytes(bytes[offset : offset + 2])
+        return offset + 2, cls.from_bytes(uuid_as_bytes[offset : offset + 2])
 
     def to_bytes(self, force_128=False):
         if len(self.uuid_bytes) == 16 or not force_128:
             return self.uuid_bytes
-        elif len(self.uuid_bytes) == 4:
+
+        if len(self.uuid_bytes) == 4:
             return self.uuid_bytes + UUID.BASE_UUID
-        else:
+
-            return self.uuid_bytes + bytes([0, 0]) + UUID.BASE_UUID
+        return self.uuid_bytes + bytes([0, 0]) + UUID.BASE_UUID
 
     def to_pdu_bytes(self):
         '''
@@ -222,19 +226,19 @@ class UUID:
         '''
         return self.to_bytes(force_128=(len(self.uuid_bytes) == 4))
 
-    def to_hex_str(self):
+    def to_hex_str(self) -> str:
         if len(self.uuid_bytes) == 2 or len(self.uuid_bytes) == 4:
             return bytes(reversed(self.uuid_bytes)).hex().upper()
-        else:
+
-            return ''.join(
+        return ''.join(
-                [
+            [
-                    bytes(reversed(self.uuid_bytes[12:16])).hex(),
+                bytes(reversed(self.uuid_bytes[12:16])).hex(),
-                    bytes(reversed(self.uuid_bytes[10:12])).hex(),
+                bytes(reversed(self.uuid_bytes[10:12])).hex(),
-                    bytes(reversed(self.uuid_bytes[8:10])).hex(),
+                bytes(reversed(self.uuid_bytes[8:10])).hex(),
-                    bytes(reversed(self.uuid_bytes[6:8])).hex(),
+                bytes(reversed(self.uuid_bytes[6:8])).hex(),
-                    bytes(reversed(self.uuid_bytes[0:6])).hex(),
+                bytes(reversed(self.uuid_bytes[0:6])).hex(),
-                ]
+            ]
-            ).upper()
+        ).upper()
 
     def __bytes__(self):
         return self.to_bytes()
@@ -242,7 +246,8 @@ class UUID:
     def __eq__(self, other):
         if isinstance(other, UUID):
             return self.to_bytes(force_128=True) == other.to_bytes(force_128=True)
-        elif type(other) is str:
+
+        if isinstance(other, str):
             return UUID(other) == self
 
         return False
@@ -252,11 +257,11 @@ class UUID:
 
     def __str__(self):
         if len(self.uuid_bytes) == 2:
-            v = struct.unpack('<H', self.uuid_bytes)[0]
+            uuid = struct.unpack('<H', self.uuid_bytes)[0]
-            result = f'UUID-16:{v:04X}'
+            result = f'UUID-16:{uuid:04X}'
         elif len(self.uuid_bytes) == 4:
-            v = struct.unpack('<I', self.uuid_bytes)[0]
+            uuid = struct.unpack('<I', self.uuid_bytes)[0]
-            result = f'UUID-32:{v:08X}'
+            result = f'UUID-32:{uuid:08X}'
         else:
             result = '-'.join(
                 [
@@ -267,10 +272,11 @@ class UUID:
                     bytes(reversed(self.uuid_bytes[0:6])).hex(),
                 ]
             ).upper()
+
         if self.name is not None:
             return result + f' ({self.name})'
-        else:
+
-            return result
+        return result
 
     def __repr__(self):
         return str(self)
@@ -280,6 +286,7 @@ class UUID:
 # Common UUID constants
 # -----------------------------------------------------------------------------
 # fmt: off
+# pylint: disable=line-too-long
 
 # Protocol Identifiers
 BT_SDP_PROTOCOL_ID                      = UUID.from_16_bits(0x0001, 'SDP')
@@ -386,6 +393,7 @@ BT_HDP_SOURCE_SERVICE                                = UUID.from_16_bits(0x1401,
 BT_HDP_SINK_SERVICE                                  = UUID.from_16_bits(0x1402, 'HDP Sink')
 
 # fmt: on
+# pylint: enable=line-too-long
 
 
 # -----------------------------------------------------------------------------
@@ -393,6 +401,7 @@ BT_HDP_SINK_SERVICE                                  = UUID.from_16_bits(0x1402,
 # -----------------------------------------------------------------------------
 class DeviceClass:
     # fmt: off
+    # pylint: disable=line-too-long
 
     # Major Service Classes (flags combined with OR)
     LIMITED_DISCOVERABLE_MODE_SERVICE_CLASS = (1 << 0)
@@ -562,6 +571,7 @@ class DeviceClass:
     }
 
     # fmt: on
+    # pylint: enable=line-too-long
 
     @staticmethod
     def split_class_of_device(class_of_device):
@@ -598,8 +608,14 @@ class DeviceClass:
 # -----------------------------------------------------------------------------
 # Advertising Data
 # -----------------------------------------------------------------------------
+AdvertisingObject = Union[
+    List[UUID], Tuple[UUID, bytes], bytes, str, int, Tuple[int, int], Tuple[int, bytes]
+]
+
+
 class AdvertisingData:
     # fmt: off
+    # pylint: disable=line-too-long
 
     # This list is only partial, it still needs to be filled in from the spec
     FLAGS                                          = 0x01
@@ -712,9 +728,14 @@ class AdvertisingData:
     BR_EDR_CONTROLLER_FLAG            = 0x08
     BR_EDR_HOST_FLAG                  = 0x10
 
-    # fmt: on
+    ad_structures: List[Tuple[int, bytes]]
 
-    def __init__(self, ad_structures=[]):
+    # fmt: on
+    # pylint: enable=line-too-long
+
+    def __init__(self, ad_structures: Optional[List[Tuple[int, bytes]]] = None) -> None:
+        if ad_structures is None:
+            ad_structures = []
         self.ad_structures = ad_structures[:]
 
     @staticmethod
@@ -739,7 +760,7 @@ class AdvertisingData:
         return ','.join(bit_flags_to_strings(flags, flag_names))
 
     @staticmethod
-    def uuid_list_to_objects(ad_data, uuid_size):
+    def uuid_list_to_objects(ad_data: bytes, uuid_size: int) -> List[UUID]:
         uuids = []
         offset = 0
         while (uuid_size * (offset + 1)) <= len(ad_data):
@@ -814,53 +835,65 @@ class AdvertisingData:
 
         return f'[{ad_type_str}]: {ad_data_str}'
 
+    # pylint: disable=too-many-return-statements
     @staticmethod
-    def ad_data_to_object(ad_type, ad_data):
+    def ad_data_to_object(ad_type: int, ad_data: bytes) -> AdvertisingObject:
-        if ad_type in {
+        if ad_type in (
             AdvertisingData.COMPLETE_LIST_OF_16_BIT_SERVICE_CLASS_UUIDS,
             AdvertisingData.INCOMPLETE_LIST_OF_16_BIT_SERVICE_CLASS_UUIDS,
             AdvertisingData.LIST_OF_16_BIT_SERVICE_SOLICITATION_UUIDS,
-        }:
+        ):
             return AdvertisingData.uuid_list_to_objects(ad_data, 2)
-        elif ad_type in {
+
+        if ad_type in (
             AdvertisingData.COMPLETE_LIST_OF_32_BIT_SERVICE_CLASS_UUIDS,
             AdvertisingData.INCOMPLETE_LIST_OF_32_BIT_SERVICE_CLASS_UUIDS,
             AdvertisingData.LIST_OF_32_BIT_SERVICE_SOLICITATION_UUIDS,
-        }:
+        ):
             return AdvertisingData.uuid_list_to_objects(ad_data, 4)
-        elif ad_type in {
+
+        if ad_type in (
             AdvertisingData.COMPLETE_LIST_OF_128_BIT_SERVICE_CLASS_UUIDS,
             AdvertisingData.INCOMPLETE_LIST_OF_128_BIT_SERVICE_CLASS_UUIDS,
             AdvertisingData.LIST_OF_128_BIT_SERVICE_SOLICITATION_UUIDS,
-        }:
+        ):
             return AdvertisingData.uuid_list_to_objects(ad_data, 16)
-        elif ad_type == AdvertisingData.SERVICE_DATA_16_BIT_UUID:
+
+        if ad_type == AdvertisingData.SERVICE_DATA_16_BIT_UUID:
             return (UUID.from_bytes(ad_data[:2]), ad_data[2:])
-        elif ad_type == AdvertisingData.SERVICE_DATA_32_BIT_UUID:
+
+        if ad_type == AdvertisingData.SERVICE_DATA_32_BIT_UUID:
             return (UUID.from_bytes(ad_data[:4]), ad_data[4:])
-        elif ad_type == AdvertisingData.SERVICE_DATA_128_BIT_UUID:
+
+        if ad_type == AdvertisingData.SERVICE_DATA_128_BIT_UUID:
             return (UUID.from_bytes(ad_data[:16]), ad_data[16:])
-        elif ad_type in {
+
+        if ad_type in (
             AdvertisingData.SHORTENED_LOCAL_NAME,
             AdvertisingData.COMPLETE_LOCAL_NAME,
             AdvertisingData.URI,
-        }:
+        ):
             return ad_data.decode("utf-8")
-        elif ad_type in {AdvertisingData.TX_POWER_LEVEL, AdvertisingData.FLAGS}:
+
-            return ad_data[0]
+        if ad_type in (AdvertisingData.TX_POWER_LEVEL, AdvertisingData.FLAGS):
-        elif ad_type in {
+            return cast(int, struct.unpack('B', ad_data)[0])
+
+        if ad_type in (
             AdvertisingData.APPEARANCE,
             AdvertisingData.ADVERTISING_INTERVAL,
-        }:
+        ):
-            return struct.unpack('<H', ad_data)[0]
+            return cast(int, struct.unpack('<H', ad_data)[0])
-        elif ad_type == AdvertisingData.CLASS_OF_DEVICE:
+
-            return struct.unpack('<I', bytes([*ad_data, 0]))[0]
+        if ad_type == AdvertisingData.CLASS_OF_DEVICE:
-        elif ad_type == AdvertisingData.PERIPHERAL_CONNECTION_INTERVAL_RANGE:
+            return cast(int, struct.unpack('<I', bytes([*ad_data, 0]))[0])
-            return struct.unpack('<HH', ad_data)
+
-        elif ad_type == AdvertisingData.MANUFACTURER_SPECIFIC_DATA:
+        if ad_type == AdvertisingData.PERIPHERAL_CONNECTION_INTERVAL_RANGE:
-            return (struct.unpack_from('<H', ad_data, 0)[0], ad_data[2:])
+            return cast(Tuple[int, int], struct.unpack('<HH', ad_data))
-        else:
+
-            return ad_data
+        if ad_type == AdvertisingData.MANUFACTURER_SPECIFIC_DATA:
+            return (cast(int, struct.unpack_from('<H', ad_data, 0)[0]), ad_data[2:])
+
+        return ad_data
 
     def append(self, data):
         offset = 0
@@ -873,30 +906,27 @@ class AdvertisingData:
                 self.ad_structures.append((ad_type, ad_data))
             offset += length
 
-    def get(self, type_id, return_all=False, raw=False):
+    def get_all(self, type_id: int, raw: bool = False) -> List[AdvertisingObject]:
         '''
         Get Advertising Data Structure(s) with a given type
 
-        If return_all is True, returns a (possibly empty) list of matches,
+        Returns a (possibly empty) list of matches.
-        else returns the first entry, or None if no structure matches.
         '''
 
-        def process_ad_data(ad_data):
+        def process_ad_data(ad_data: bytes) -> AdvertisingObject:
             return ad_data if raw else self.ad_data_to_object(type_id, ad_data)
 
-        if return_all:
+        return [process_ad_data(ad[1]) for ad in self.ad_structures if ad[0] == type_id]
-            return [
+
-                process_ad_data(ad[1]) for ad in self.ad_structures if ad[0] == type_id
+    def get(self, type_id: int, raw: bool = False) -> Optional[AdvertisingObject]:
-            ]
+        '''
-        else:
+        Get Advertising Data Structure(s) with a given type
-            return next(
+
-                (
+        Returns the first entry, or None if no structure matches.
-                    process_ad_data(ad[1])
+        '''
-                    for ad in self.ad_structures
+
-                    if ad[0] == type_id
+        all = self.get_all(type_id, raw=raw)
-                ),
+        return all[0] if all else None
-                None,
-            )
 
     def __bytes__(self):
         return b''.join(

bumble/crypto.py

@@ -125,7 +125,7 @@ def e(key, data):
 
 
 # -----------------------------------------------------------------------------
-def ah(k, r):
+def ah(k, r):  # pylint: disable=redefined-outer-name
     '''
     See Bluetooth spec Vol 3, Part H - 2.2.2 Random Address Hash function ah
     '''
@@ -136,9 +136,10 @@ def ah(k, r):
 
 
 # -----------------------------------------------------------------------------
-def c1(k, r, preq, pres, iat, rat, ia, ra):
+def c1(k, r, preq, pres, iat, rat, ia, ra):  # pylint: disable=redefined-outer-name
     '''
-    See Bluetooth spec, Vol 3, Part H - 2.2.3 Confirm value generation function c1 for LE Legacy Pairing
+    See Bluetooth spec, Vol 3, Part H - 2.2.3 Confirm value generation function c1 for
+    LE Legacy Pairing
     '''
 
     p1 = bytes([iat, rat]) + preq + pres
@@ -149,7 +150,8 @@ def c1(k, r, preq, pres, iat, rat, ia, ra):
 # -----------------------------------------------------------------------------
 def s1(k, r1, r2):
     '''
-    See Bluetooth spec, Vol 3, Part H - 2.2.4 Key generation function s1 for LE Legacy Pairing
+    See Bluetooth spec, Vol 3, Part H - 2.2.4 Key generation function s1 for LE Legacy
+    Pairing
     '''
 
     return e(k, r2[0:8] + r1[0:8])
@@ -170,7 +172,8 @@ def aes_cmac(m, k):
 # -----------------------------------------------------------------------------
 def f4(u, v, x, z):
     '''
-    See Bluetooth spec, Vol 3, Part H - 2.2.6 LE Secure Connections Confirm Value Generation Function f4
+    See Bluetooth spec, Vol 3, Part H - 2.2.6 LE Secure Connections Confirm Value
+    Generation Function f4
     '''
     return bytes(
         reversed(
@@ -182,7 +185,8 @@ def f4(u, v, x, z):
 # -----------------------------------------------------------------------------
 def f5(w, n1, n2, a1, a2):
     '''
-    See Bluetooth spec, Vol 3, Part H - 2.2.7 LE Secure Connections Key Generation Function f5
+    See Bluetooth spec, Vol 3, Part H - 2.2.7 LE Secure Connections Key Generation
+    Function f5
 
     NOTE: this returns a tuple: (MacKey, LTK) in little-endian byte order
     '''
@@ -222,9 +226,10 @@ def f5(w, n1, n2, a1, a2):
 
 
 # -----------------------------------------------------------------------------
-def f6(w, n1, n2, r, io_cap, a1, a2):
+def f6(w, n1, n2, r, io_cap, a1, a2):  # pylint: disable=redefined-outer-name
     '''
-    See Bluetooth spec, Vol 3, Part H - 2.2.8 LE Secure Connections Check Value Generation Function f6
+    See Bluetooth spec, Vol 3, Part H - 2.2.8 LE Secure Connections Check Value
+    Generation Function f6
     '''
     return bytes(
         reversed(
@@ -244,7 +249,8 @@ def f6(w, n1, n2, r, io_cap, a1, a2):
 # -----------------------------------------------------------------------------
 def g2(u, v, x, y):
     '''
-    See Bluetooth spec, Vol 3, Part H - 2.2.9 LE Secure Connections Numeric Comparison Value Generation Function g2
+    See Bluetooth spec, Vol 3, Part H - 2.2.9 LE Secure Connections Numeric Comparison
+    Value Generation Function g2
     '''
     return int.from_bytes(
         aes_cmac(

bumble/gatt.py

@@ -25,14 +25,15 @@
 from __future__ import annotations
 import asyncio
 import enum
-import types
+import functools
 import logging
-from pyee import EventEmitter
+import struct
+from typing import Optional, Sequence
 from colors import color
 
-from .core import *
+from .core import UUID, get_dict_key_by_value
-from .hci import *
+from .att import Attribute
-from .att import *
+
 
 # -----------------------------------------------------------------------------
 # Logging
@@ -43,6 +44,7 @@ logger = logging.getLogger(__name__)
 # Constants
 # -----------------------------------------------------------------------------
 # fmt: off
+# pylint: disable=line-too-long
 
 GATT_REQUEST_TIMEOUT = 30  # seconds
 
@@ -177,6 +179,7 @@ GATT_BOOT_KEYBOARD_OUTPUT_REPORT_CHARACTERISTIC                = UUID.from_16_bi
 GATT_CENTRAL_ADDRESS_RESOLUTION__CHARACTERISTIC                = UUID.from_16_bits(0x2AA6, 'Central Address Resolution')
 
 # fmt: on
+# pylint: enable=line-too-long
 
 
 # -----------------------------------------------------------------------------
@@ -201,9 +204,11 @@ class Service(Attribute):
     See Vol 3, Part G - 3.1 SERVICE DEFINITION
     '''
 
+    uuid: UUID
+
     def __init__(self, uuid, characteristics: list[Characteristic], primary=True):
         # Convert the uuid to a UUID object if it isn't already
-        if type(uuid) is str:
+        if isinstance(uuid, str):
             uuid = UUID(uuid)
 
         super().__init__(
@@ -214,11 +219,11 @@ class Service(Attribute):
             uuid.to_pdu_bytes(),
         )
         self.uuid = uuid
-        self.included_services = []
+        # self.included_services = []
         self.characteristics = characteristics[:]
         self.primary = primary
 
-    def get_advertising_data(self):
+    def get_advertising_data(self) -> Optional[bytes]:
         """
         Get Service specific advertising data
         Defined by each Service, default value is empty
@@ -227,7 +232,12 @@ class Service(Attribute):
         return None
 
     def __str__(self):
-        return f'Service(handle=0x{self.handle:04X}, end=0x{self.end_group_handle:04X}, uuid={self.uuid}){"" if self.primary else "*"}'
+        return (
+            f'Service(handle=0x{self.handle:04X}, '
+            f'end=0x{self.end_group_handle:04X}, '
+            f'uuid={self.uuid})'
+            f'{"" if self.primary else "*"}'
+        )
 
 
 # -----------------------------------------------------------------------------
@@ -271,15 +281,15 @@ class Characteristic(Attribute):
     }
 
     @staticmethod
-    def property_name(property):
+    def property_name(property_int):
-        return Characteristic.PROPERTY_NAMES.get(property, '')
+        return Characteristic.PROPERTY_NAMES.get(property_int, '')
 
     @staticmethod
     def properties_as_string(properties):
         return ','.join(
             [
                 Characteristic.property_name(p)
-                for p in Characteristic.PROPERTY_NAMES.keys()
+                for p in Characteristic.PROPERTY_NAMES
                 if properties & p
             ]
         )
@@ -298,11 +308,11 @@ class Characteristic(Attribute):
         properties,
         permissions,
         value=b'',
-        descriptors: list[Descriptor] = [],
+        descriptors: Sequence[Descriptor] = (),
     ):
         super().__init__(uuid, permissions, value)
         self.uuid = self.type
-        if type(properties) is str:
+        if isinstance(properties, str):
             self.properties = Characteristic.string_to_properties(properties)
         else:
             self.properties = properties
@@ -313,8 +323,15 @@ class Characteristic(Attribute):
             if descriptor.type == descriptor_type:
                 return descriptor
 
+        return None
+
     def __str__(self):
-        return f'Characteristic(handle=0x{self.handle:04X}, end=0x{self.end_group_handle:04X}, uuid={self.uuid}, properties={Characteristic.properties_as_string(self.properties)})'
+        return (
+            f'Characteristic(handle=0x{self.handle:04X}, '
+            f'end=0x{self.end_group_handle:04X}, '
+            f'uuid={self.uuid}, '
+            f'properties={Characteristic.properties_as_string(self.properties)})'
+        )
 
 
 # -----------------------------------------------------------------------------
@@ -335,7 +352,12 @@ class CharacteristicDeclaration(Attribute):
         self.characteristic = characteristic
 
     def __str__(self):
-        return f'CharacteristicDeclaration(handle=0x{self.handle:04X}, value_handle=0x{self.value_handle:04X}, uuid={self.characteristic.uuid}, properties={Characteristic.properties_as_string(self.characteristic.properties)})'
+        return (
+            f'CharacteristicDeclaration(handle=0x{self.handle:04X}, '
+            f'value_handle=0x{self.value_handle:04X}, '
+            f'uuid={self.characteristic.uuid}, properties='
+            f'{Characteristic.properties_as_string(self.characteristic.properties)})'
+        )
 
 
 # -----------------------------------------------------------------------------
@@ -395,14 +417,14 @@ class CharacteristicAdapter:
         return getattr(self.wrapped_characteristic, name)
 
     def __setattr__(self, name, value):
-        if name in {
+        if name in (
             'wrapped_characteristic',
             'subscribers',
             'read_value',
             'write_value',
             'subscribe',
             'unsubscribe',
-        }:
+        ):
             super().__setattr__(name, value)
         else:
             setattr(self.wrapped_characteristic, name, value)
@@ -486,9 +508,9 @@ class PackedCharacteristicAdapter(CharacteristicAdapter):
     the format.
     '''
 
-    def __init__(self, characteristic, format):
+    def __init__(self, characteristic, pack_format):
         super().__init__(characteristic)
-        self.struct = struct.Struct(format)
+        self.struct = struct.Struct(pack_format)
 
     def pack(self, *values):
         return self.struct.pack(*values)
@@ -497,7 +519,7 @@ class PackedCharacteristicAdapter(CharacteristicAdapter):
         return self.struct.unpack(buffer)
 
     def encode_value(self, value):
-        return self.pack(*value if type(value) is tuple else (value,))
+        return self.pack(*value if isinstance(value, tuple) else (value,))
 
     def decode_value(self, value):
         unpacked = self.unpack(value)
@@ -510,14 +532,15 @@ class MappedCharacteristicAdapter(PackedCharacteristicAdapter):
     Adapter that packs/unpacks characteristic values according to a standard
     Python `struct` format.
     The adapted `read_value` and `write_value` methods return/accept aa dictionary which
-    is packed/unpacked according to format, with the arguments extracted from the dictionary
+    is packed/unpacked according to format, with the arguments extracted from the
-    by key, in the same order as they occur in the `keys` parameter.
+    dictionary by key, in the same order as they occur in the `keys` parameter.
     '''
 
-    def __init__(self, characteristic, format, keys):
+    def __init__(self, characteristic, pack_format, keys):
-        super().__init__(characteristic, format)
+        super().__init__(characteristic, pack_format)
         self.keys = keys
 
+    # pylint: disable=arguments-differ
     def pack(self, values):
         return super().pack(*(values[key] for key in self.keys))
 
@@ -544,16 +567,18 @@ class Descriptor(Attribute):
     See Vol 3, Part G - 3.3.3 Characteristic Descriptor Declarations
     '''
 
-    def __init__(self, descriptor_type, permissions, value=b''):
-        super().__init__(descriptor_type, permissions, value)
-
     def __str__(self):
-        return f'Descriptor(handle=0x{self.handle:04X}, type={self.type}, value={self.read_value(None).hex()})'
+        return (
+            f'Descriptor(handle=0x{self.handle:04X}, '
+            f'type={self.type}, '
+            f'value={self.read_value(None).hex()})'
+        )
 
 
 class ClientCharacteristicConfigurationBits(enum.IntFlag):
     '''
-    See Vol 3, Part G - 3.3.3.3 - Table 3.11 Client Characteristic Configuration bit field definition
+    See Vol 3, Part G - 3.3.3.3 - Table 3.11 Client Characteristic Configuration bit
+    field definition
     '''
 
     DEFAULT = 0x0000

bumble/gatt_client.py

@@ -28,9 +28,31 @@ import logging
 import struct
 
 from colors import color
+from pyee import EventEmitter
 
-from .att import *
+from .hci import HCI_Constant
-from .core import InvalidStateError, ProtocolError, TimeoutError
+from .att import (
+    ATT_ATTRIBUTE_NOT_FOUND_ERROR,
+    ATT_ATTRIBUTE_NOT_LONG_ERROR,
+    ATT_CID,
+    ATT_DEFAULT_MTU,
+    ATT_ERROR_RESPONSE,
+    ATT_INVALID_OFFSET_ERROR,
+    ATT_PDU,
+    ATT_RESPONSES,
+    ATT_Exchange_MTU_Request,
+    ATT_Find_By_Type_Value_Request,
+    ATT_Find_Information_Request,
+    ATT_Handle_Value_Confirmation,
+    ATT_Read_Blob_Request,
+    ATT_Read_By_Group_Type_Request,
+    ATT_Read_By_Type_Request,
+    ATT_Read_Request,
+    ATT_Write_Command,
+    ATT_Write_Request,
+)
+from . import core
+from .core import UUID, InvalidStateError, ProtocolError
 from .gatt import (
     GATT_CHARACTERISTIC_ATTRIBUTE_TYPE,
     GATT_CLIENT_CHARACTERISTIC_CONFIGURATION_DESCRIPTOR,
@@ -40,7 +62,6 @@ from .gatt import (
     Characteristic,
     ClientCharacteristicConfigurationBits,
 )
-from .hci import *
 
 # -----------------------------------------------------------------------------
 # Logging
@@ -76,16 +97,17 @@ class AttributeProxy(EventEmitter):
         return value_bytes
 
     def __str__(self):
-        return f'Attribute(handle=0x{self.handle:04X}, type={self.uuid})'
+        return f'Attribute(handle=0x{self.handle:04X}, type={self.type})'
 
 
 class ServiceProxy(AttributeProxy):
     @staticmethod
-    def from_client(cls, client, service_uuid):
+    def from_client(service_class, client, service_uuid):
-        # The service and its characteristics are considered to have already been discovered
+        # The service and its characteristics are considered to have already been
+        # discovered
         services = client.get_services_by_uuid(service_uuid)
         service = services[0] if services else None
-        return cls(service) if service else None
+        return service_class(service) if service else None
 
     def __init__(self, client, handle, end_group_handle, uuid, primary=True):
         attribute_type = (
@@ -97,7 +119,7 @@ class ServiceProxy(AttributeProxy):
         self.uuid = uuid
         self.characteristics = []
 
-    async def discover_characteristics(self, uuids=[]):
+    async def discover_characteristics(self, uuids=()):
         return await self.client.discover_characteristics(uuids, self)
 
     def get_characteristics_by_uuid(self, uuid):
@@ -121,6 +143,8 @@ class CharacteristicProxy(AttributeProxy):
             if descriptor.type == descriptor_type:
                 return descriptor
 
+        return None
+
     async def discover_descriptors(self):
         return await self.client.discover_descriptors(self)
 
@@ -148,7 +172,11 @@ class CharacteristicProxy(AttributeProxy):
         return await self.client.unsubscribe(self, subscriber)
 
     def __str__(self):
-        return f'Characteristic(handle=0x{self.handle:04X}, uuid={self.uuid}, properties={Characteristic.properties_as_string(self.properties)})'
+        return (
+            f'Characteristic(handle=0x{self.handle:04X}, '
+            f'uuid={self.uuid}, '
+            f'properties={Characteristic.properties_as_string(self.properties)})'
+        )
 
 
 class DescriptorProxy(AttributeProxy):
@@ -214,9 +242,9 @@ class Client:
                 response = await asyncio.wait_for(
                     self.pending_response, GATT_REQUEST_TIMEOUT
                 )
-            except asyncio.TimeoutError:
+            except asyncio.TimeoutError as error:
                 logger.warning(color('!!! GATT Request timeout', 'red'))
-                raise TimeoutError(f'GATT timeout for {request.name}')
+                raise core.TimeoutError(f'GATT timeout for {request.name}') from error
             finally:
                 self.pending_request = None
                 self.pending_response = None
@@ -225,7 +253,8 @@ class Client:
 
     def send_confirmation(self, confirmation):
         logger.debug(
-            f'GATT Confirmation from client: [0x{self.connection.handle:04X}] {confirmation}'
+            f'GATT Confirmation from client: [0x{self.connection.handle:04X}] '
+            f'{confirmation}'
         )
         self.send_gatt_pdu(confirmation.to_bytes())
 
@@ -300,7 +329,8 @@ class Client:
                 if response.error_code != ATT_ATTRIBUTE_NOT_FOUND_ERROR:
                     # Unexpected end
                     logger.warning(
-                        f'!!! unexpected error while discovering services: {HCI_Constant.error_name(response.error_code)}'
+                        '!!! unexpected error while discovering services: '
+                        f'{HCI_Constant.error_name(response.error_code)}'
                     )
                     # TODO raise appropriate exception
                     return
@@ -352,7 +382,7 @@ class Client:
         '''
 
         # Force uuid to be a UUID object
-        if type(uuid) is str:
+        if isinstance(uuid, str):
             uuid = UUID(uuid)
 
         starting_handle = 0x0001
@@ -375,7 +405,8 @@ class Client:
                 if response.error_code != ATT_ATTRIBUTE_NOT_FOUND_ERROR:
                     # Unexpected end
                     logger.warning(
-                        f'!!! unexpected error while discovering services: {HCI_Constant.error_name(response.error_code)}'
+                        '!!! unexpected error while discovering services: '
+                        f'{HCI_Constant.error_name(response.error_code)}'
                     )
                     # TODO raise appropriate exception
                     return
@@ -414,7 +445,7 @@ class Client:
 
         return services
 
-    async def discover_included_services(self, service):
+    async def discover_included_services(self, _service):
         '''
         See Vol 3, Part G - 4.5.1 Find Included Services
         '''
@@ -423,11 +454,12 @@ class Client:
 
     async def discover_characteristics(self, uuids, service):
         '''
-        See Vol 3, Part G - 4.6.1 Discover All Characteristics of a Service and 4.6.2 Discover Characteristics by UUID
+        See Vol 3, Part G - 4.6.1 Discover All Characteristics of a Service and 4.6.2
+        Discover Characteristics by UUID
         '''
 
         # Cast the UUIDs type from string to object if needed
-        uuids = [UUID(uuid) if type(uuid) is str else uuid for uuid in uuids]
+        uuids = [UUID(uuid) if isinstance(uuid, str) else uuid for uuid in uuids]
 
         # Decide which services to discover for
         services = [service] if service else self.services
@@ -456,7 +488,8 @@ class Client:
                     if response.error_code != ATT_ATTRIBUTE_NOT_FOUND_ERROR:
                         # Unexpected end
                         logger.warning(
-                            f'!!! unexpected error while discovering characteristics: {HCI_Constant.error_name(response.error_code)}'
+                            '!!! unexpected error while discovering characteristics: '
+                            f'{HCI_Constant.error_name(response.error_code)}'
                         )
                         # TODO raise appropriate exception
                         return
@@ -532,7 +565,8 @@ class Client:
                 if response.error_code != ATT_ATTRIBUTE_NOT_FOUND_ERROR:
                     # Unexpected end
                     logger.warning(
-                        f'!!! unexpected error while discovering descriptors: {HCI_Constant.error_name(response.error_code)}'
+                        '!!! unexpected error while discovering descriptors: '
+                        f'{HCI_Constant.error_name(response.error_code)}'
                     )
                     # TODO raise appropriate exception
                     return []
@@ -585,7 +619,8 @@ class Client:
                 if response.error_code != ATT_ATTRIBUTE_NOT_FOUND_ERROR:
                     # Unexpected end
                     logger.warning(
-                        f'!!! unexpected error while discovering attributes: {HCI_Constant.error_name(response.error_code)}'
+                        '!!! unexpected error while discovering attributes: '
+                        f'{HCI_Constant.error_name(response.error_code)}'
                     )
                     return []
                 break
@@ -607,7 +642,8 @@ class Client:
         return attributes
 
     async def subscribe(self, characteristic, subscriber=None, prefer_notify=True):
-        # If we haven't already discovered the descriptors for this characteristic, do it now
+        # If we haven't already discovered the descriptors for this characteristic,
+        # do it now
         if not characteristic.descriptors_discovered:
             await self.discover_descriptors(characteristic)
 
@@ -642,14 +678,16 @@ class Client:
         subscriber_set = subscribers.setdefault(characteristic.handle, set())
         if subscriber is not None:
             subscriber_set.add(subscriber)
-        # Add the characteristic as a subscriber, which will result in the characteristic
+        # Add the characteristic as a subscriber, which will result in the
-        # emitting an 'update' event when a notification or indication is received
+        # characteristic emitting an 'update' event when a notification or indication
+        # is received
         subscriber_set.add(characteristic)
 
         await self.write_value(cccd, struct.pack('<H', bits), with_response=True)
 
     async def unsubscribe(self, characteristic, subscriber=None):
-        # If we haven't already discovered the descriptors for this characteristic, do it now
+        # If we haven't already discovered the descriptors for this characteristic,
+        # do it now
         if not characteristic.descriptors_discovered:
             await self.discover_descriptors(characteristic)
 
@@ -673,7 +711,7 @@ class Client:
 
                     # Cleanup if we removed the last one
                     if not subscribers:
-                        subscriber_set.remove(characteristic.handle)
+                        del subscriber_set[characteristic.handle]
         else:
             # Remove all subscribers for this attribute from the sets!
             self.notification_subscribers.pop(characteristic.handle, None)
@@ -691,7 +729,7 @@ class Client:
         '''
 
         # Send a request to read
-        attribute_handle = attribute if type(attribute) is int else attribute.handle
+        attribute_handle = attribute if isinstance(attribute, int) else attribute.handle
         response = await self.send_request(
             ATT_Read_Request(attribute_handle=attribute_handle)
         )
@@ -720,9 +758,9 @@ class Client:
                 if response is None:
                     raise TimeoutError('read timeout')
                 if response.op_code == ATT_ERROR_RESPONSE:
-                    if (
+                    if response.error_code in (
-                        response.error_code == ATT_ATTRIBUTE_NOT_LONG_ERROR
+                        ATT_ATTRIBUTE_NOT_LONG_ERROR,
-                        or response.error_code == ATT_INVALID_OFFSET_ERROR
+                        ATT_INVALID_OFFSET_ERROR,
                     ):
                         break
                     raise ProtocolError(
@@ -773,7 +811,8 @@ class Client:
                 if response.error_code != ATT_ATTRIBUTE_NOT_FOUND_ERROR:
                     # Unexpected end
                     logger.warning(
-                        f'!!! unexpected error while reading characteristics: {HCI_Constant.error_name(response.error_code)}'
+                        '!!! unexpected error while reading characteristics: '
+                        f'{HCI_Constant.error_name(response.error_code)}'
                     )
                     # TODO raise appropriate exception
                     return []
@@ -799,13 +838,14 @@ class Client:
 
     async def write_value(self, attribute, value, with_response=False):
         '''
-        See Vol 3, Part G - 4.9.1 Write Without Response & 4.9.3 Write Characteristic Value
+        See Vol 3, Part G - 4.9.1 Write Without Response & 4.9.3 Write Characteristic
+        Value
 
         `attribute` can be an Attribute object, or a handle value
         '''
 
         # Send a request or command to write
-        attribute_handle = attribute if type(attribute) is int else attribute.handle
+        attribute_handle = attribute if isinstance(attribute, int) else attribute.handle
         if with_response:
             response = await self.send_request(
                 ATT_Write_Request(
@@ -836,7 +876,8 @@ class Client:
                 logger.warning('!!! unexpected response, there is no pending request')
                 return
 
-            # Sanity check: the response should match the pending request unless it is an error response
+            # Sanity check: the response should match the pending request unless it is
+            # an error response
             if att_pdu.op_code != ATT_ERROR_RESPONSE:
                 expected_response_name = self.pending_request.name.replace(
                     '_REQUEST', '_RESPONSE'
@@ -856,7 +897,12 @@ class Client:
                 handler(att_pdu)
             else:
                 logger.warning(
-                    f'{color(f"--- Ignoring GATT Response from [0x{self.connection.handle:04X}]:", "red")} {att_pdu}'
+                    color(
+                        '--- Ignoring GATT Response from '
+                        f'[0x{self.connection.handle:04X}]: ',
+                        'red',
+                    )
+                    + str(att_pdu)
                 )
 
     def on_att_handle_value_notification(self, notification):

bumble/gatt_server.py

@@ -26,14 +26,53 @@
 import asyncio
 import logging
 from collections import defaultdict
-from typing import Tuple, Optional
+import struct
+from typing import List, Tuple, Optional
 from pyee import EventEmitter
 from colors import color
 
-from .core import *
+from .core import UUID
-from .hci import *
+from .att import (
-from .att import *
+    ATT_ATTRIBUTE_NOT_FOUND_ERROR,
-from .gatt import *
+    ATT_ATTRIBUTE_NOT_LONG_ERROR,
+    ATT_CID,
+    ATT_DEFAULT_MTU,
+    ATT_INVALID_ATTRIBUTE_LENGTH_ERROR,
+    ATT_INVALID_HANDLE_ERROR,
+    ATT_INVALID_OFFSET_ERROR,
+    ATT_REQUEST_NOT_SUPPORTED_ERROR,
+    ATT_REQUESTS,
+    ATT_UNLIKELY_ERROR_ERROR,
+    ATT_UNSUPPORTED_GROUP_TYPE_ERROR,
+    ATT_Error,
+    ATT_Error_Response,
+    ATT_Exchange_MTU_Response,
+    ATT_Find_By_Type_Value_Response,
+    ATT_Find_Information_Response,
+    ATT_Handle_Value_Indication,
+    ATT_Handle_Value_Notification,
+    ATT_Read_Blob_Response,
+    ATT_Read_By_Group_Type_Response,
+    ATT_Read_By_Type_Response,
+    ATT_Read_Response,
+    ATT_Write_Response,
+    Attribute,
+)
+from .gatt import (
+    GATT_CHARACTERISTIC_ATTRIBUTE_TYPE,
+    GATT_CLIENT_CHARACTERISTIC_CONFIGURATION_DESCRIPTOR,
+    GATT_INCLUDE_ATTRIBUTE_TYPE,
+    GATT_MAX_ATTRIBUTE_VALUE_SIZE,
+    GATT_PRIMARY_SERVICE_ATTRIBUTE_TYPE,
+    GATT_REQUEST_TIMEOUT,
+    GATT_SECONDARY_SERVICE_ATTRIBUTE_TYPE,
+    Characteristic,
+    CharacteristicDeclaration,
+    CharacteristicValue,
+    Descriptor,
+    Service,
+)
+
 
 # -----------------------------------------------------------------------------
 # Logging
@@ -51,6 +90,8 @@ GATT_SERVER_DEFAULT_MAX_MTU = 517
 # GATT Server
 # -----------------------------------------------------------------------------
 class Server(EventEmitter):
+    attributes: List[Attribute]
+
     def __init__(self, device):
         super().__init__()
         self.device = device
@@ -101,6 +142,7 @@ class Server(EventEmitter):
                 attribute
                 for attribute in self.attributes
                 if attribute.type == GATT_PRIMARY_SERVICE_ATTRIBUTE_TYPE
+                and isinstance(attribute, Service)
                 and attribute.uuid == service_uuid
             ),
             None,
@@ -194,6 +236,7 @@ class Server(EventEmitter):
                 is None
             ):
                 self.add_attribute(
+                    # pylint: disable=line-too-long
                     Descriptor(
                         GATT_CLIENT_CHARACTERISTIC_CONFIGURATION_DESCRIPTOR,
                         Attribute.READABLE | Attribute.WRITEABLE,
@@ -232,12 +275,13 @@ class Server(EventEmitter):
 
     def write_cccd(self, connection, characteristic, value):
         logger.debug(
-            f'Subscription update for connection=0x{connection.handle:04X}, handle=0x{characteristic.handle:04X}: {value.hex()}'
+            f'Subscription update for connection=0x{connection.handle:04X}, '
+            f'handle=0x{characteristic.handle:04X}: {value.hex()}'
         )
 
         # Sanity check
         if len(value) != 2:
-            logger.warn('CCCD value not 2 bytes long')
+            logger.warning('CCCD value not 2 bytes long')
             return
 
         cccds = self.subscribers.setdefault(connection.handle, {})
@@ -349,9 +393,9 @@ class Server(EventEmitter):
                 await asyncio.wait_for(
                     self.pending_confirmations[connection.handle], GATT_REQUEST_TIMEOUT
                 )
-            except asyncio.TimeoutError:
+            except asyncio.TimeoutError as error:
                 logger.warning(color('!!! GATT Indicate timeout', 'red'))
-                raise TimeoutError(f'GATT timeout for {indication.name}')
+                raise TimeoutError(f'GATT timeout for {indication.name}') from error
             finally:
                 self.pending_confirmations[connection.handle] = None
 
@@ -425,7 +469,11 @@ class Server(EventEmitter):
             else:
                 # Just ignore
                 logger.warning(
-                    f'{color("--- Ignoring GATT Request from [0x{connection.handle:04X}]:", "red")}  {att_pdu}'
+                    color(
+                        f'--- Ignoring GATT Request from [0x{connection.handle:04X}]: ',
+                        'red',
+                    )
+                    + str(att_pdu)
                 )
 
     #######################################################
@@ -436,7 +484,10 @@ class Server(EventEmitter):
         Handler for requests without a more specific handler
         '''
         logger.warning(
-            f'{color(f"--- Unsupported ATT Request from [0x{connection.handle:04X}]:", "red")} {pdu}'
+            color(
+                f'--- Unsupported ATT Request from [0x{connection.handle:04X}]: ', 'red'
+            )
+            + str(pdu)
         )
         response = ATT_Error_Response(
             request_opcode_in_error=pdu.op_code,
@@ -556,11 +607,11 @@ class Server(EventEmitter):
         if attributes:
             handles_information_list = []
             for attribute in attributes:
-                if attribute.type in {
+                if attribute.type in (
                     GATT_PRIMARY_SERVICE_ATTRIBUTE_TYPE,
                     GATT_SECONDARY_SERVICE_ATTRIBUTE_TYPE,
                     GATT_CHARACTERISTIC_ATTRIBUTE_TYPE,
-                }:
+                ):
                     # Part of a group
                     group_end_handle = attribute.end_group_handle
                 else:
@@ -692,11 +743,11 @@ class Server(EventEmitter):
         '''
         See Bluetooth spec Vol 3, Part F - 3.4.4.9 Read by Group Type Request
         '''
-        if request.attribute_group_type not in {
+        if request.attribute_group_type not in (
             GATT_PRIMARY_SERVICE_ATTRIBUTE_TYPE,
             GATT_SECONDARY_SERVICE_ATTRIBUTE_TYPE,
             GATT_INCLUDE_ATTRIBUTE_TYPE,
-        }:
+        ):
             response = ATT_Error_Response(
                 request_opcode_in_error=request.op_code,
                 attribute_handle_in_error=request.starting_handle,
@@ -814,7 +865,7 @@ class Server(EventEmitter):
         except Exception as error:
             logger.warning(f'!!! ignoring exception: {error}')
 
-    def on_att_handle_value_confirmation(self, connection, confirmation):
+    def on_att_handle_value_confirmation(self, connection, _confirmation):
         '''
         See Bluetooth spec Vol 3, Part F - 3.4.7.3 Handle Value Confirmation
         '''

bumble/hci.py

@@ -15,13 +15,24 @@
 # -----------------------------------------------------------------------------
 # Imports
 # -----------------------------------------------------------------------------
+from __future__ import annotations
 import struct
 import collections
 import logging
 import functools
 from colors import color
+from typing import Dict, Type, Union
+
+from .core import (
+    BT_BR_EDR_TRANSPORT,
+    AdvertisingData,
+    DeviceClass,
+    ProtocolError,
+    bit_flags_to_strings,
+    name_or_number,
+    padded_bytes,
+)
 
-from .core import *
 
 # -----------------------------------------------------------------------------
 # Logging
@@ -43,8 +54,8 @@ def key_with_value(dictionary, target_value):
     return None
 
 
-def indent_lines(str):
+def indent_lines(string):
-    return '\n'.join(['  ' + line for line in str.split('\n')])
+    return '\n'.join(['  ' + line for line in string.split('\n')])
 
 
 def map_null_terminated_utf8_string(utf8_bytes):
@@ -63,25 +74,32 @@ def map_class_of_device(class_of_device):
         major_device_class,
         minor_device_class,
     ) = DeviceClass.split_class_of_device(class_of_device)
-    return f'[{class_of_device:06X}] Services({",".join(DeviceClass.service_class_labels(service_classes))}),Class({DeviceClass.major_device_class_name(major_device_class)}|{DeviceClass.minor_device_class_name(major_device_class, minor_device_class)})'
+    return (
+        f'[{class_of_device:06X}] Services('
+        f'{",".join(DeviceClass.service_class_labels(service_classes))}),'
+        f'Class({DeviceClass.major_device_class_name(major_device_class)}|'
+        f'{DeviceClass.minor_device_class_name(major_device_class, minor_device_class)}'
+        ')'
+    )
 
 
 def phy_list_to_bits(phys):
     if phys is None:
         return 0
-    else:
+
-        phy_bits = 0
+    phy_bits = 0
-        for phy in phys:
+    for phy in phys:
-            if phy not in HCI_LE_PHY_TYPE_TO_BIT:
+        if phy not in HCI_LE_PHY_TYPE_TO_BIT:
-                raise ValueError('invalid PHY')
+            raise ValueError('invalid PHY')
-            phy_bits |= 1 << HCI_LE_PHY_TYPE_TO_BIT[phy]
+        phy_bits |= 1 << HCI_LE_PHY_TYPE_TO_BIT[phy]
-        return phy_bits
+    return phy_bits
 
 
 # -----------------------------------------------------------------------------
 # Constants
 # -----------------------------------------------------------------------------
 # fmt: off
+# pylint: disable=line-too-long
 
 # HCI Version
 HCI_VERSION_BLUETOOTH_CORE_1_0B    = 0
@@ -1355,8 +1373,11 @@ HCI_LE_SUPPORTED_FEATURES_NAMES = {
 }
 
 # fmt: on
+# pylint: enable=line-too-long
+# pylint: disable=invalid-name
 
 # -----------------------------------------------------------------------------
+# pylint: disable-next=unnecessary-lambda
 STATUS_SPEC = {'size': 1, 'mapper': lambda x: HCI_Constant.status_name(x)}
 
 
@@ -1418,25 +1439,25 @@ class HCI_StatusError(ProtocolError):
 # -----------------------------------------------------------------------------
 class HCI_Object:
     @staticmethod
-    def init_from_fields(object, fields, values):
+    def init_from_fields(hci_object, fields, values):
-        if type(values) is dict:
+        if isinstance(values, dict):
             for field_name, _ in fields:
-                setattr(object, field_name, values[field_name])
+                setattr(hci_object, field_name, values[field_name])
         else:
             for field_name, field_value in zip(fields, values):
-                setattr(object, field_name, field_value)
+                setattr(hci_object, field_name, field_value)
 
     @staticmethod
-    def init_from_bytes(object, data, offset, fields):
+    def init_from_bytes(hci_object, data, offset, fields):
         parsed = HCI_Object.dict_from_bytes(data, offset, fields)
-        HCI_Object.init_from_fields(object, parsed.keys(), parsed.values())
+        HCI_Object.init_from_fields(hci_object, parsed.keys(), parsed.values())
 
     @staticmethod
     def dict_from_bytes(data, offset, fields):
         result = collections.OrderedDict()
         for (field_name, field_type) in fields:
             # The field_type may be a dictionary with a mapper, parser, and/or size
-            if type(field_type) is dict:
+            if isinstance(field_type, dict):
                 if 'size' in field_type:
                     field_type = field_type['size']
                 elif 'parser' in field_type:
@@ -1480,7 +1501,7 @@ class HCI_Object:
                 # 32-bit unsigned big-endian
                 field_value = struct.unpack_from('>I', data, offset)[0]
                 offset += 4
-            elif type(field_type) is int and field_type > 4 and field_type <= 256:
+            elif isinstance(field_type, int) and 4 < field_type <= 256:
                 # Byte array (from 5 up to 256 bytes)
                 field_value = data[offset : offset + field_type]
                 offset += field_type
@@ -1494,19 +1515,20 @@ class HCI_Object:
         return result
 
     @staticmethod
-    def dict_to_bytes(object, fields):
+    def dict_to_bytes(hci_object, fields):
         result = bytearray()
         for (field_name, field_type) in fields:
-            # The field_type may be a dictionary with a mapper, parser, serializer, and/or size
+            # The field_type may be a dictionary with a mapper, parser, serializer,
+            # and/or size
             serializer = None
-            if type(field_type) is dict:
+            if isinstance(field_type, dict):
                 if 'serializer' in field_type:
                     serializer = field_type['serializer']
                 if 'size' in field_type:
                     field_type = field_type['size']
 
             # Serialize the field
-            field_value = object[field_name]
+            field_value = hci_object[field_name]
             if serializer:
                 field_bytes = serializer(field_value)
             elif field_type == 1:
@@ -1534,20 +1556,18 @@ class HCI_Object:
                 # 32-bit unsigned big-endian
                 field_bytes = struct.pack('>I', field_value)
             elif field_type == '*':
-                if type(field_value) is int:
+                if isinstance(field_value, int):
-                    if field_value >= 0 and field_value <= 255:
+                    if 0 <= field_value <= 255:
                         field_bytes = bytes([field_value])
                     else:
                         raise ValueError('value too large for *-typed field')
                 else:
                     field_bytes = bytes(field_value)
-            elif (
+            elif isinstance(field_value, (bytes, bytearray)) or hasattr(
-                type(field_value) is bytes
+                field_value, 'to_bytes'
-                or type(field_value) is bytearray
-                or hasattr(field_value, 'to_bytes')
             ):
                 field_bytes = bytes(field_value)
-                if type(field_type) is int and field_type > 4 and field_type <= 256:
+                if isinstance(field_type, int) and 4 < field_type <= 256:
                     # Truncate or Pad with zeros if the field is too long or too short
                     if len(field_bytes) < field_type:
                         field_bytes += bytes(field_type - len(field_bytes))
@@ -1584,40 +1604,42 @@ class HCI_Object:
 
     @staticmethod
     def format_field_value(value, indentation):
-        if type(value) is bytes:
+        if isinstance(value, bytes):
             return value.hex()
-        elif isinstance(value, HCI_Object):
+
+        if isinstance(value, HCI_Object):
             return '\n' + value.to_string(indentation)
-        else:
+
-            return str(value)
+        return str(value)
 
     @staticmethod
-    def format_fields(object, keys, indentation='', value_mappers={}):
+    def format_fields(hci_object, keys, indentation='', value_mappers=None):
         if not keys:
             return ''
 
         # Measure the widest field name
         max_field_name_length = max(
-            [len(key[0] if type(key) is tuple else key) for key in keys]
+            (len(key[0] if isinstance(key, tuple) else key) for key in keys)
         )
 
         # Build array of formatted key:value pairs
         fields = []
         for key in keys:
             value_mapper = None
-            if type(key) is tuple:
+            if isinstance(key, tuple):
                 # The key has an associated specifier
                 key, specifier = key
 
                 # Get the value mapper from the specifier
-                if type(specifier) is dict:
+                if isinstance(specifier, dict):
                     value_mapper = specifier.get('mapper')
 
             # Get the value for the field
-            value = object[key]
+            value = hci_object[key]
 
             # Map the value if needed
-            value_mapper = value_mappers.get(key, value_mapper)
+            if value_mappers:
+                value_mapper = value_mappers.get(key, value_mapper)
             if value_mapper is not None:
                 value = value_mapper(value)
 
@@ -1639,7 +1661,7 @@ class HCI_Object:
         self.fields = fields
         self.init_from_fields(self, fields, kwargs)
 
-    def to_string(self, indentation='', value_mappers={}):
+    def to_string(self, indentation='', value_mappers=None):
         return HCI_Object.format_fields(
             self.__dict__, self.fields, indentation, value_mappers
         )
@@ -1670,6 +1692,12 @@ class Address:
         RANDOM_IDENTITY_ADDRESS: 'RANDOM_IDENTITY_ADDRESS',
     }
 
+    # Type declarations
+    NIL: Address
+    ANY: Address
+    ANY_RANDOM: Address
+
+    # pylint: disable-next=unnecessary-lambda
     ADDRESS_TYPE_SPEC = {'size': 1, 'mapper': lambda x: Address.address_type_name(x)}
 
     @staticmethod
@@ -1686,7 +1714,8 @@ class Address:
 
     @staticmethod
     def parse_address(data, offset):
-        # Fix the type to a default value. This is used for parsing type-less Classic addresses
+        # Fix the type to a default value. This is used for parsing type-less Classic
+        # addresses
         return Address.parse_address_with_type(
             data, offset, Address.PUBLIC_DEVICE_ADDRESS
         )
@@ -1700,15 +1729,17 @@ class Address:
         address_type = data[offset - 1]
         return Address.parse_address_with_type(data, offset, address_type)
 
-    def __init__(self, address, address_type=RANDOM_DEVICE_ADDRESS):
+    def __init__(
+        self, address: Union[bytes, str], address_type: int = RANDOM_DEVICE_ADDRESS
+    ):
         '''
         Initialize an instance. `address` may be a byte array in little-endian
         format, or a hex string in big-endian format (with optional ':'
         separators between the bytes).
-        If the address is a string suffixed with '/P', `address_type` is ignored and the type
+        If the address is a string suffixed with '/P', `address_type` is ignored and
-        is set to PUBLIC_DEVICE_ADDRESS.
+        the type is set to PUBLIC_DEVICE_ADDRESS.
         '''
-        if type(address) is bytes:
+        if isinstance(address, bytes):
             self.address_bytes = address
         else:
             # Check if there's a '/P' type specifier
@@ -1731,9 +1762,9 @@ class Address:
 
     @property
     def is_public(self):
-        return (
+        return self.address_type in (
-            self.address_type == self.PUBLIC_DEVICE_ADDRESS
+            self.PUBLIC_DEVICE_ADDRESS,
-            or self.address_type == self.PUBLIC_IDENTITY_ADDRESS
+            self.PUBLIC_IDENTITY_ADDRESS,
         )
 
     @property
@@ -1742,9 +1773,9 @@ class Address:
 
     @property
     def is_resolved(self):
-        return (
+        return self.address_type in (
-            self.address_type == self.PUBLIC_IDENTITY_ADDRESS
+            self.PUBLIC_IDENTITY_ADDRESS,
-            or self.address_type == self.RANDOM_IDENTITY_ADDRESS
+            self.RANDOM_IDENTITY_ADDRESS,
         )
 
     @property
@@ -1776,15 +1807,16 @@ class Address:
         '''
         String representation of the address, MSB first
         '''
-        str = ':'.join([f'{x:02X}' for x in reversed(self.address_bytes)])
+        result = ':'.join([f'{x:02X}' for x in reversed(self.address_bytes)])
         if not self.is_public:
-            return str
+            return result
-        return str + '/P'
+        return result + '/P'
 
 
 # Predefined address values
 Address.NIL = Address(b"\xff\xff\xff\xff\xff\xff", Address.PUBLIC_DEVICE_ADDRESS)
 Address.ANY = Address(b"\x00\x00\x00\x00\x00\x00", Address.PUBLIC_DEVICE_ADDRESS)
+Address.ANY_RANDOM = Address(b"\x00\x00\x00\x00\x00\x00", Address.RANDOM_DEVICE_ADDRESS)
 
 # -----------------------------------------------------------------------------
 class OwnAddressType:
@@ -1801,9 +1833,10 @@ class OwnAddressType:
     }
 
     @staticmethod
-    def type_name(type):
+    def type_name(type_id):
-        return name_or_number(OwnAddressType.TYPE_NAMES, type)
+        return name_or_number(OwnAddressType.TYPE_NAMES, type_id)
 
+    # pylint: disable-next=unnecessary-lambda
     TYPE_SPEC = {'size': 1, 'mapper': lambda x: OwnAddressType.type_name(x)}
 
 
@@ -1816,14 +1849,17 @@ class HCI_Packet:
     @staticmethod
     def from_bytes(packet):
         packet_type = packet[0]
+
         if packet_type == HCI_COMMAND_PACKET:
             return HCI_Command.from_bytes(packet)
-        elif packet_type == HCI_ACL_DATA_PACKET:
+
+        if packet_type == HCI_ACL_DATA_PACKET:
             return HCI_AclDataPacket.from_bytes(packet)
-        elif packet_type == HCI_EVENT_PACKET:
+
+        if packet_type == HCI_EVENT_PACKET:
             return HCI_Event.from_bytes(packet)
-        else:
+
-            return HCI_CustomPacket(packet)
+        return HCI_CustomPacket(packet)
 
     def __init__(self, name):
         self.name = name
@@ -1847,10 +1883,10 @@ class HCI_Command(HCI_Packet):
     '''
 
     hci_packet_type = HCI_COMMAND_PACKET
-    command_classes = {}
+    command_classes: Dict[int, Type[HCI_Command]] = {}
 
     @staticmethod
-    def command(fields=[], return_parameters_fields=[]):
+    def command(fields=(), return_parameters_fields=()):
         '''
         Decorator used to declare and register subclasses
         '''
@@ -1897,8 +1933,8 @@ class HCI_Command(HCI_Packet):
             HCI_Command.__init__(self, op_code, parameters)
             HCI_Object.init_from_bytes(self, parameters, 0, fields)
             return self
-        else:
+
-            return cls.from_parameters(parameters)
+        return cls.from_parameters(parameters)
 
     @staticmethod
     def command_name(op_code):
@@ -2842,6 +2878,7 @@ class HCI_LE_Set_Random_Address_Command(HCI_Command):
 
 # -----------------------------------------------------------------------------
 @HCI_Command.command(
+    # pylint: disable=line-too-long,unnecessary-lambda
     [
         ('advertising_interval_min', 2),
         ('advertising_interval_max', 2),
@@ -3077,6 +3114,16 @@ class HCI_LE_Read_Remote_Features_Command(HCI_Command):
     '''
 
 
+# -----------------------------------------------------------------------------
+@HCI_Command.command(
+    return_parameters_fields=[("status", STATUS_SPEC), ("random_number", 8)]
+)
+class HCI_LE_Rand_Command(HCI_Command):
+    """
+    See Bluetooth spec @ 7.8.23 LE Rand Command
+    """
+
+
 # -----------------------------------------------------------------------------
 @HCI_Command.command(
     [
@@ -3089,7 +3136,8 @@ class HCI_LE_Read_Remote_Features_Command(HCI_Command):
 class HCI_LE_Enable_Encryption_Command(HCI_Command):
     '''
     See Bluetooth spec @ 7.8.24 LE Enable Encryption Command
-    (renamed from "LE Start Encryption Command" in version prior to 5.2 of the specification)
+    (renamed from "LE Start Encryption Command" in version prior to 5.2 of the
+    specification)
     '''
 
 
@@ -3144,7 +3192,8 @@ class HCI_LE_Remote_Connection_Parameter_Request_Reply_Command(HCI_Command):
 )
 class HCI_LE_Remote_Connection_Parameter_Request_Negative_Reply_Command(HCI_Command):
     '''
-    See Bluetooth spec @ 7.8.32 LE Remote Connection Parameter Request Negative Reply Command
+    See Bluetooth spec @ 7.8.32 LE Remote Connection Parameter Request Negative Reply
+    Command
     '''
 
 
@@ -3356,6 +3405,7 @@ class HCI_LE_Set_Advertising_Set_Random_Address_Command(HCI_Command):
 
 # -----------------------------------------------------------------------------
 @HCI_Command.command(
+    # pylint: disable=line-too-long,unnecessary-lambda
     fields=[
         ('advertising_handle', 1),
         (
@@ -3422,6 +3472,7 @@ class HCI_LE_Set_Extended_Advertising_Parameters_Command(HCI_Command):
 
     @classmethod
     def advertising_properties_string(cls, properties):
+        # pylint: disable=line-too-long
         return f'[{",".join(bit_flags_to_strings(properties, cls.ADVERTISING_PROPERTIES_NAMES))}]'
 
     @classmethod
@@ -3431,6 +3482,7 @@ class HCI_LE_Set_Extended_Advertising_Parameters_Command(HCI_Command):
 
 # -----------------------------------------------------------------------------
 @HCI_Command.command(
+    # pylint: disable=line-too-long,unnecessary-lambda
     [
         ('advertising_handle', 1),
         (
@@ -3480,6 +3532,7 @@ class HCI_LE_Set_Extended_Advertising_Data_Command(HCI_Command):
 
 # -----------------------------------------------------------------------------
 @HCI_Command.command(
+    # pylint: disable=line-too-long,unnecessary-lambda
     [
         ('advertising_handle', 1),
         (
@@ -3573,9 +3626,9 @@ class HCI_LE_Set_Extended_Advertising_Enable_Command(HCI_Command):
 
     def __str__(self):
         fields = [('enable:', self.enable)]
-        for i in range(len(self.advertising_handles)):
+        for i, advertising_handle in enumerate(self.advertising_handles):
             fields.append(
-                (f'advertising_handle[{i}]:             ', self.advertising_handles[i])
+                (f'advertising_handle[{i}]:             ', advertising_handle)
             )
             fields.append((f'duration[{i}]:                       ', self.durations[i]))
             fields.append(
@@ -3736,7 +3789,7 @@ class HCI_LE_Set_Extended_Scan_Parameters_Command(HCI_Command):
             )
             fields.append(
                 (f'{scanning_phy_str}.scan_interval:', self.scan_intervals[i])
-            ),
+            )
             fields.append((f'{scanning_phy_str}.scan_window:  ', self.scan_windows[i]))
 
         return (
@@ -3871,43 +3924,43 @@ class HCI_LE_Extended_Create_Connection_Command(HCI_Command):
                     f'{initiating_phys_str}.scan_interval:          ',
                     self.scan_intervals[i],
                 )
-            ),
+            )
             fields.append(
                 (
                     f'{initiating_phys_str}.scan_window:            ',
                     self.scan_windows[i],
                 )
-            ),
+            )
             fields.append(
                 (
                     f'{initiating_phys_str}.connection_interval_min:',
                     self.connection_interval_mins[i],
                 )
-            ),
+            )
             fields.append(
                 (
                     f'{initiating_phys_str}.connection_interval_max:',
                     self.connection_interval_maxs[i],
                 )
-            ),
+            )
             fields.append(
                 (
                     f'{initiating_phys_str}.max_latency:            ',
                     self.max_latencies[i],
                 )
-            ),
+            )
             fields.append(
                 (
                     f'{initiating_phys_str}.supervision_timeout:    ',
                     self.supervision_timeouts[i],
                 )
-            ),
+            )
             fields.append(
                 (
                     f'{initiating_phys_str}.min_ce_length:          ',
                     self.min_ce_lengths[i],
                 )
-            ),
+            )
             fields.append(
                 (
                     f'{initiating_phys_str}.max_ce_length:          ',
@@ -3933,6 +3986,7 @@ class HCI_LE_Extended_Create_Connection_Command(HCI_Command):
             'privacy_mode',
             {
                 'size': 1,
+                # pylint: disable-next=unnecessary-lambda
                 'mapper': lambda x: HCI_LE_Set_Privacy_Mode_Command.privacy_mode_name(
                     x
                 ),
@@ -3975,11 +4029,11 @@ class HCI_Event(HCI_Packet):
     '''
 
     hci_packet_type = HCI_EVENT_PACKET
-    event_classes = {}
+    event_classes: Dict[int, Type[HCI_Event]] = {}
-    meta_event_classes = {}
+    meta_event_classes: Dict[int, Type[HCI_LE_Meta_Event]] = {}
 
     @staticmethod
-    def event(fields=[]):
+    def event(fields=()):
         '''
         Decorator used to declare and register subclasses
         '''
@@ -4005,16 +4059,16 @@ class HCI_Event(HCI_Packet):
         return inner
 
     @staticmethod
-    def registered(cls):
+    def registered(event_class):
-        cls.name = cls.__name__.upper()
+        event_class.name = event_class.__name__.upper()
-        cls.event_code = key_with_value(HCI_EVENT_NAMES, cls.name)
+        event_class.event_code = key_with_value(HCI_EVENT_NAMES, event_class.name)
-        if cls.event_code is None:
+        if event_class.event_code is None:
             raise KeyError('event not found in HCI_EVENT_NAMES')
 
         # Register a factory for this class
-        HCI_Event.event_classes[cls.event_code] = cls
+        HCI_Event.event_classes[event_class.event_code] = event_class
 
-        return cls
+        return event_class
 
     @staticmethod
     def from_bytes(packet):
@@ -4025,7 +4079,8 @@ class HCI_Event(HCI_Packet):
             raise ValueError('invalid packet length')
 
         if event_code == HCI_LE_META_EVENT:
-            # We do this dispatch here and not in the subclass in order to avoid call loops
+            # We do this dispatch here and not in the subclass in order to avoid call
+            # loops
             subevent_code = parameters[0]
             cls = HCI_Event.meta_event_classes.get(subevent_code)
             if cls is None:
@@ -4086,7 +4141,7 @@ class HCI_LE_Meta_Event(HCI_Event):
     '''
 
     @staticmethod
-    def event(fields=[]):
+    def event(fields=()):
         '''
         Decorator used to declare and register subclasses
         '''
@@ -4214,9 +4269,9 @@ class HCI_LE_Advertising_Report_Event(HCI_LE_Meta_Event):
         def event_type_string(self):
             return HCI_LE_Advertising_Report_Event.event_type_name(self.event_type)
 
-        def to_string(self, prefix):
+        def to_string(self, indentation='', _=None):
             return super().to_string(
-                prefix,
+                indentation,
                 {
                     'event_type': HCI_LE_Advertising_Report_Event.event_type_name,
                     'address_type': Address.address_type_name,
@@ -4443,9 +4498,10 @@ class HCI_LE_Extended_Advertising_Report_Event(HCI_LE_Meta_Event):
                 self.event_type
             )
 
-        def to_string(self, prefix):
+        def to_string(self, indentation='', _=None):
+            # pylint: disable=line-too-long
             return super().to_string(
-                prefix,
+                indentation,
                 {
                     'event_type': HCI_LE_Extended_Advertising_Report_Event.event_type_string,
                     'address_type': Address.address_type_name,
@@ -4472,6 +4528,7 @@ class HCI_LE_Extended_Advertising_Report_Event(HCI_LE_Meta_Event):
                 )
             )
             if legacy_pdu_type is not None:
+                # pylint: disable=line-too-long
                 legacy_info_string = f'({HCI_LE_Advertising_Report_Event.event_type_name(legacy_pdu_type)})'
             else:
                 legacy_info_string = ''
@@ -4587,6 +4644,7 @@ class HCI_Inquiry_Result_Event(HCI_Event):
             'link_type',
             {
                 'size': 1,
+                # pylint: disable-next=unnecessary-lambda
                 'mapper': lambda x: HCI_Connection_Complete_Event.link_type_name(x),
             },
         ),
@@ -4622,6 +4680,7 @@ class HCI_Connection_Complete_Event(HCI_Event):
             'link_type',
             {
                 'size': 1,
+                # pylint: disable-next=unnecessary-lambda
                 'mapper': lambda x: HCI_Connection_Complete_Event.link_type_name(x),
             },
         ),
@@ -4678,6 +4737,7 @@ class HCI_Remote_Name_Request_Complete_Event(HCI_Event):
             'encryption_enabled',
             {
                 'size': 1,
+                # pylint: disable-next=unnecessary-lambda
                 'mapper': lambda x: HCI_Encryption_Change_Event.encryption_enabled_name(
                     x
                 ),
@@ -4746,16 +4806,20 @@ class HCI_Command_Complete_Event(HCI_Event):
     See Bluetooth spec @ 7.7.14 Command Complete Event
     '''
 
+    return_parameters = b''
+
     def map_return_parameters(self, return_parameters):
-        # Map simple 'status' return parameters to their named constant form
+        '''Map simple 'status' return parameters to their named constant form'''
-        if type(return_parameters) is bytes and len(return_parameters) == 1:
+
+        if isinstance(return_parameters, bytes) and len(return_parameters) == 1:
             # Byte-array form
             return HCI_Constant.status_name(return_parameters[0])
-        elif type(return_parameters) is int:
+
+        if isinstance(return_parameters, int):
             # Already converted to an integer status code
             return HCI_Constant.status_name(return_parameters)
-        else:
+
-            return return_parameters
+        return return_parameters
 
     @staticmethod
     def from_parameters(parameters):
@@ -4766,8 +4830,12 @@ class HCI_Command_Complete_Event(HCI_Event):
         )
 
         # Parse the return parameters
-        if type(self.return_parameters) is bytes and len(self.return_parameters) == 1:
+        if (
-            # All commands with 1-byte return parameters return a 'status' field, convert it to an integer
+            isinstance(self.return_parameters, bytes)
+            and len(self.return_parameters) == 1
+        ):
+            # All commands with 1-byte return parameters return a 'status' field,
+            # convert it to an integer
             self.return_parameters = self.return_parameters[0]
         else:
             cls = HCI_Command.command_classes.get(self.command_opcode)
@@ -4793,6 +4861,7 @@ class HCI_Command_Complete_Event(HCI_Event):
     [
         (
             'status',
+            # pylint: disable-next=unnecessary-lambda
             {'size': 1, 'mapper': lambda x: HCI_Command_Status_Event.status_name(x)},
         ),
         ('num_hci_command_packets', 1),
@@ -4810,8 +4879,8 @@ class HCI_Command_Status_Event(HCI_Event):
     def status_name(status):
         if status == HCI_Command_Status_Event.PENDING:
             return 'PENDING'
-        else:
+
-            return HCI_Constant.error_name(status)
+        return HCI_Constant.error_name(status)
 
 
 # -----------------------------------------------------------------------------
@@ -4869,10 +4938,10 @@ class HCI_Number_Of_Completed_Packets_Event(HCI_Event):
             color('  number_of_handles:         ', 'cyan')
             + f'{len(self.connection_handles)}',
         ]
-        for i in range(len(self.connection_handles)):
+        for i, connection_handle in enumerate(self.connection_handles):
             lines.append(
                 color(f'  connection_handle[{i}]:     ', 'cyan')
-                + f'{self.connection_handles[i]}'
+                + f'{connection_handle}'
             )
             lines.append(
                 color(f'  num_completed_packets[{i}]: ', 'cyan')
@@ -4888,6 +4957,7 @@ class HCI_Number_Of_Completed_Packets_Event(HCI_Event):
         ('connection_handle', 2),
         (
             'current_mode',
+            # pylint: disable-next=unnecessary-lambda
             {'size': 1, 'mapper': lambda x: HCI_Mode_Change_Event.mode_name(x)},
         ),
         ('interval', 2),
@@ -5044,6 +5114,7 @@ class HCI_Read_Remote_Extended_Features_Complete_Event(HCI_Event):
 
 # -----------------------------------------------------------------------------
 @HCI_Event.event(
+    # pylint: disable=line-too-long
     [
         ('status', STATUS_SPEC),
         ('connection_handle', 2),
@@ -5052,6 +5123,7 @@ class HCI_Read_Remote_Extended_Features_Complete_Event(HCI_Event):
             'link_type',
             {
                 'size': 1,
+                # pylint: disable-next=unnecessary-lambda
                 'mapper': lambda x: HCI_Synchronous_Connection_Complete_Event.link_type_name(
                     x
                 ),
@@ -5065,6 +5137,7 @@ class HCI_Read_Remote_Extended_Features_Complete_Event(HCI_Event):
             'air_mode',
             {
                 'size': 1,
+                # pylint: disable-next=unnecessary-lambda
                 'mapper': lambda x: HCI_Synchronous_Connection_Complete_Event.air_mode_name(
                     x
                 ),
@@ -5229,7 +5302,7 @@ class HCI_Remote_Host_Supported_Features_Notification_Event(HCI_Event):
 
 
 # -----------------------------------------------------------------------------
-class HCI_AclDataPacket(HCI_Packet):
+class HCI_AclDataPacket:
     '''
     See Bluetooth spec @ 5.4.2 HCI ACL Data Packets
     '''
@@ -5268,7 +5341,13 @@ class HCI_AclDataPacket(HCI_Packet):
         return self.to_bytes()
 
     def __str__(self):
-        return f'{color("ACL", "blue")}: handle=0x{self.connection_handle:04x}, pb={self.pb_flag}, bc={self.bc_flag}, data_total_length={self.data_total_length}, data={self.data.hex()}'
+        return (
+            f'{color("ACL", "blue")}: '
+            f'handle=0x{self.connection_handle:04x}'
+            f'pb={self.pb_flag}, bc={self.bc_flag}, '
+            f'data_total_length={self.data_total_length}, '
+            f'data={self.data.hex()}'
+        )
 
 
 # -----------------------------------------------------------------------------
@@ -5279,9 +5358,9 @@ class HCI_AclDataPacketAssembler:
         self.l2cap_pdu_length = 0
 
     def feed_packet(self, packet):
-        if (
+        if packet.pb_flag in (
-            packet.pb_flag == HCI_ACL_PB_FIRST_NON_FLUSHABLE
+            HCI_ACL_PB_FIRST_NON_FLUSHABLE,
-            or packet.pb_flag == HCI_ACL_PB_FIRST_FLUSHABLE
+            HCI_ACL_PB_FIRST_FLUSHABLE,
         ):
             (l2cap_pdu_length,) = struct.unpack_from('<H', packet.data, 0)
             self.current_data = packet.data

bumble/helpers.py

@@ -18,10 +18,9 @@
 import logging
 from colors import color
 
-from bumble.smp import SMP_CID, SMP_Command
+from .att import ATT_CID, ATT_PDU
-
+from .smp import SMP_CID, SMP_Command
 from .core import name_or_number
-from .gatt import ATT_PDU, ATT_CID
 from .l2cap import (
     L2CAP_PDU,
     L2CAP_CONNECTION_REQUEST,
@@ -66,6 +65,7 @@ class PacketTracer:
             self.psms = {}  # PSM, by source_cid
             self.peer = None  # ACL stream in the other direction
 
+        # pylint: disable=too-many-nested-blocks
         def on_acl_pdu(self, pdu):
             l2cap_pdu = L2CAP_PDU.from_bytes(pdu)
 
@@ -75,10 +75,7 @@ class PacketTracer:
             elif l2cap_pdu.cid == SMP_CID:
                 smp_command = SMP_Command.from_bytes(l2cap_pdu.payload)
                 self.analyzer.emit(smp_command)
-            elif (
+            elif l2cap_pdu.cid in (L2CAP_SIGNALING_CID, L2CAP_LE_SIGNALING_CID):
-                l2cap_pdu.cid == L2CAP_SIGNALING_CID
-                or l2cap_pdu.cid == L2CAP_LE_SIGNALING_CID
-            ):
                 control_frame = L2CAP_Control_Frame.from_bytes(l2cap_pdu.payload)
                 self.analyzer.emit(control_frame)
 
@@ -95,7 +92,8 @@ class PacketTracer:
                                 # Found a pending connection
                                 self.psms[control_frame.destination_cid] = psm
 
-                                # For AVDTP connections, create a packet assembler for each direction
+                                # For AVDTP connections, create a packet assembler for
+                                # each direction
                                 if psm == AVDTP_PSM:
                                     self.avdtp_assemblers[
                                         control_frame.source_cid
@@ -117,7 +115,8 @@ class PacketTracer:
                         self.analyzer.emit(rfcomm_frame)
                     elif psm == AVDTP_PSM:
                         self.analyzer.emit(
-                            f'{color("L2CAP", "green")} [CID={l2cap_pdu.cid}, PSM=AVDTP]: {l2cap_pdu.payload.hex()}'
+                            f'{color("L2CAP", "green")} [CID={l2cap_pdu.cid}, '
+                            f'PSM=AVDTP]: {l2cap_pdu.payload.hex()}'
                         )
                         assembler = self.avdtp_assemblers.get(l2cap_pdu.cid)
                         if assembler:
@@ -125,7 +124,8 @@ class PacketTracer:
                     else:
                         psm_string = name_or_number(PSM_NAMES, psm)
                         self.analyzer.emit(
-                            f'{color("L2CAP", "green")} [CID={l2cap_pdu.cid}, PSM={psm_string}]: {l2cap_pdu.payload.hex()}'
+                            f'{color("L2CAP", "green")} [CID={l2cap_pdu.cid}, '
+                            f'PSM={psm_string}]: {l2cap_pdu.payload.hex()}'
                         )
                 else:
                     self.analyzer.emit(l2cap_pdu)
@@ -147,7 +147,8 @@ class PacketTracer:
 
         def start_acl_stream(self, connection_handle):
             logger.info(
-                f'[{self.label}] +++ Creating ACL stream for connection 0x{connection_handle:04X}'
+                f'[{self.label}] +++ Creating ACL stream for connection '
+                f'0x{connection_handle:04X}'
             )
             stream = PacketTracer.AclStream(self)
             self.acl_streams[connection_handle] = stream
@@ -162,7 +163,8 @@ class PacketTracer:
         def end_acl_stream(self, connection_handle):
             if connection_handle in self.acl_streams:
                 logger.info(
-                    f'[{self.label}] --- Removing ACL stream for connection 0x{connection_handle:04X}'
+                    f'[{self.label}] --- Removing ACL stream for connection '
+                    f'0x{connection_handle:04X}'
                 )
                 del self.acl_streams[connection_handle]
 

bumble/hfp.py

@@ -43,7 +43,7 @@ class HfpProtocol:
 
     def feed(self, data):
         # Convert the data to a string if needed
-        if type(data) == bytes:
+        if isinstance(data, bytes):
             data = data.decode('utf-8')
 
         logger.debug(f'<<< Data received: {data}')
@@ -79,16 +79,16 @@ class HfpProtocol:
     async def initialize_service(self):
         # Perform Service Level Connection Initialization
         self.send_command_line('AT+BRSF=2072')  # Retrieve Supported Features
-        line = await (self.next_line())
+        await (self.next_line())
-        line = await (self.next_line())
+        await (self.next_line())
 
         self.send_command_line('AT+CIND=?')
-        line = await (self.next_line())
+        await (self.next_line())
-        line = await (self.next_line())
+        await (self.next_line())
 
         self.send_command_line('AT+CIND?')
-        line = await (self.next_line())
+        await (self.next_line())
-        line = await (self.next_line())
+        await (self.next_line())
 
         self.send_command_line('AT+CMER=3,0,0,1')
-        line = await (self.next_line())
+        await (self.next_line())

bumble/host.py

@@ -16,16 +16,60 @@
 # Imports
 # -----------------------------------------------------------------------------
 import asyncio
+import collections
 import logging
-from pyee import EventEmitter
+import struct
+
 from colors import color
 
-from .hci import *
+from bumble.l2cap import L2CAP_PDU
-from .l2cap import *
+
-from .att import *
+from .hci import (
-from .gatt import *
+    HCI_ACL_DATA_PACKET,
-from .smp import *
+    HCI_COMMAND_COMPLETE_EVENT,
-from .core import ConnectionParameters
+    HCI_COMMAND_PACKET,
+    HCI_EVENT_PACKET,
+    HCI_LE_READ_BUFFER_SIZE_COMMAND,
+    HCI_LE_READ_LOCAL_SUPPORTED_FEATURES_COMMAND,
+    HCI_LE_READ_SUGGESTED_DEFAULT_DATA_LENGTH_COMMAND,
+    HCI_LE_WRITE_SUGGESTED_DEFAULT_DATA_LENGTH_COMMAND,
+    HCI_READ_BUFFER_SIZE_COMMAND,
+    HCI_READ_LOCAL_VERSION_INFORMATION_COMMAND,
+    HCI_RESET_COMMAND,
+    HCI_SUCCESS,
+    HCI_SUPPORTED_COMMANDS_FLAGS,
+    HCI_VERSION_BLUETOOTH_CORE_4_0,
+    HCI_AclDataPacket,
+    HCI_AclDataPacketAssembler,
+    HCI_Constant,
+    HCI_Error,
+    HCI_LE_Long_Term_Key_Request_Negative_Reply_Command,
+    HCI_LE_Long_Term_Key_Request_Reply_Command,
+    HCI_LE_Read_Buffer_Size_Command,
+    HCI_LE_Read_Local_Supported_Features_Command,
+    HCI_LE_Read_Suggested_Default_Data_Length_Command,
+    HCI_LE_Remote_Connection_Parameter_Request_Reply_Command,
+    HCI_LE_Set_Event_Mask_Command,
+    HCI_LE_Write_Suggested_Default_Data_Length_Command,
+    HCI_Link_Key_Request_Negative_Reply_Command,
+    HCI_Link_Key_Request_Reply_Command,
+    HCI_PIN_Code_Request_Negative_Reply_Command,
+    HCI_Packet,
+    HCI_Read_Buffer_Size_Command,
+    HCI_Read_Local_Supported_Commands_Command,
+    HCI_Read_Local_Version_Information_Command,
+    HCI_Reset_Command,
+    HCI_Set_Event_Mask_Command,
+)
+from .core import (
+    BT_BR_EDR_TRANSPORT,
+    BT_CENTRAL_ROLE,
+    BT_LE_TRANSPORT,
+    ConnectionPHY,
+    ConnectionParameters,
+)
+from .utils import AbortableEventEmitter
+
 
 # -----------------------------------------------------------------------------
 # Logging
@@ -65,12 +109,13 @@ class Connection:
 
 
 # -----------------------------------------------------------------------------
-class Host(EventEmitter):
+class Host(AbortableEventEmitter):
     def __init__(self, controller_source=None, controller_sink=None):
         super().__init__()
 
         self.hci_sink = None
         self.ready = False  # True when we can accept incoming packets
+        self.reset_done = False
         self.connections = {}  # Connections, by connection handle
         self.pending_command = None
         self.pending_response = None
@@ -96,7 +141,19 @@ class Host(EventEmitter):
         if controller_sink:
             self.set_packet_sink(controller_sink)
 
+    async def flush(self) -> None:
+        # Make sure no command is pending
+        await self.command_semaphore.acquire()
+
+        # Flush current host state, then release command semaphore
+        self.emit('flush')
+        self.command_semaphore.release()
+
     async def reset(self):
+        if self.ready:
+            self.ready = False
+            await self.flush()
+
         await self.send_command(HCI_Reset_Command(), check_result=True)
         self.ready = True
 
@@ -127,10 +184,12 @@ class Host(EventEmitter):
             self.local_version is not None
             and self.local_version.hci_version <= HCI_VERSION_BLUETOOTH_CORE_4_0
         ):
-            # Some older controllers don't like event masks with bits they don't understand
+            # Some older controllers don't like event masks with bits they don't
+            # understand
             le_event_mask = bytes.fromhex('1F00000000000000')
         else:
             le_event_mask = bytes.fromhex('FFFFF00000000000')
+
         await self.send_command(
             HCI_LE_Set_Event_Mask_Command(le_event_mask=le_event_mask)
         )
@@ -147,7 +206,8 @@ class Host(EventEmitter):
             )
 
             logger.debug(
-                f'HCI ACL flow control: hc_acl_data_packet_length={self.hc_acl_data_packet_length},'
+                'HCI ACL flow control: '
+                f'hc_acl_data_packet_length={self.hc_acl_data_packet_length},'
                 f'hc_total_num_acl_data_packets={self.hc_total_num_acl_data_packets}'
             )
 
@@ -163,8 +223,10 @@ class Host(EventEmitter):
             )
 
             logger.debug(
-                f'HCI LE ACL flow control: hc_le_acl_data_packet_length={self.hc_le_acl_data_packet_length},'
+                'HCI LE ACL flow control: '
-                f'hc_total_num_le_acl_data_packets={self.hc_total_num_le_acl_data_packets}'
+                f'hc_le_acl_data_packet_length={self.hc_le_acl_data_packet_length},'
+                'hc_total_num_le_acl_data_packets='
+                f'{self.hc_total_num_le_acl_data_packets}'
             )
 
             if (
@@ -232,9 +294,9 @@ class Host(EventEmitter):
 
                 # Check the return parameters if required
                 if check_result:
-                    if type(response.return_parameters) is int:
+                    if isinstance(response.return_parameters, int):
                         status = response.return_parameters
-                    elif type(response.return_parameters) is bytes:
+                    elif isinstance(response.return_parameters, bytes):
                         # return parameters first field is a one byte status code
                         status = response.return_parameters[0]
                     else:
@@ -294,7 +356,8 @@ class Host(EventEmitter):
 
         if len(self.acl_packet_queue):
             logger.debug(
-                f'{self.acl_packets_in_flight} ACL packets in flight, {len(self.acl_packet_queue)} in queue'
+                f'{self.acl_packets_in_flight} ACL packets in flight, '
+                f'{len(self.acl_packet_queue)} in queue'
             )
 
     def check_acl_packet_queue(self):
@@ -388,7 +451,9 @@ class Host(EventEmitter):
             # Check that it is what we were expecting
             if self.pending_command.op_code != event.command_opcode:
                 logger.warning(
-                    f'!!! command result mismatch, expected 0x{self.pending_command.op_code:X} but got 0x{event.command_opcode:X}'
+                    '!!! command result mismatch, expected '
+                    f'0x{self.pending_command.op_code:X} but got '
+                    f'0x{event.command_opcode:X}'
                 )
 
             self.pending_response.set_result(event)
@@ -403,10 +468,12 @@ class Host(EventEmitter):
 
     def on_hci_command_complete_event(self, event):
         if event.command_opcode == 0:
-            # This is used just for the Num_HCI_Command_Packets field, not related to an actual command
+            # This is used just for the Num_HCI_Command_Packets field, not related to
+            # an actual command
             logger.debug('no-command event')
-        else:
+            return None
-            return self.on_command_processed(event)
+
+        return self.on_command_processed(event)
 
     def on_hci_command_status_event(self, event):
         return self.on_command_processed(event)
@@ -419,7 +486,8 @@ class Host(EventEmitter):
         else:
             logger.warning(
                 color(
-                    f'!!! {total_packets} completed but only {self.acl_packets_in_flight} in flight'
+                    '!!! {total_packets} completed but only '
+                    f'{self.acl_packets_in_flight} in flight'
                 )
             )
             self.acl_packets_in_flight = 0
@@ -439,7 +507,8 @@ class Host(EventEmitter):
         if event.status == HCI_SUCCESS:
             # Create/update the connection
             logger.debug(
-                f'### CONNECTION: [0x{event.connection_handle:04X}] {event.peer_address} as {HCI_Constant.role_name(event.role)}'
+                f'### CONNECTION: [0x{event.connection_handle:04X}] '
+                f'{event.peer_address} as {HCI_Constant.role_name(event.role)}'
             )
 
             connection = self.connections.get(event.connection_handle)
@@ -484,7 +553,8 @@ class Host(EventEmitter):
         if event.status == HCI_SUCCESS:
             # Create/update the connection
             logger.debug(
-                f'### BR/EDR CONNECTION: [0x{event.connection_handle:04X}] {event.bd_addr}'
+                f'### BR/EDR CONNECTION: [0x{event.connection_handle:04X}] '
+                f'{event.bd_addr}'
             )
 
             connection = self.connections.get(event.connection_handle)
@@ -524,7 +594,10 @@ class Host(EventEmitter):
 
         if event.status == HCI_SUCCESS:
             logger.debug(
-                f'### DISCONNECTION: [0x{event.connection_handle:04X}] {connection.peer_address} as {HCI_Constant.role_name(connection.role)}, reason={event.reason}'
+                f'### DISCONNECTION: [0x{event.connection_handle:04X}] '
+                f'{connection.peer_address} as '
+                f'{HCI_Constant.role_name(connection.role)}, '
+                f'reason={event.reason}'
             )
             del self.connections[event.connection_handle]
 
@@ -587,7 +660,7 @@ class Host(EventEmitter):
                 connection_handle=event.connection_handle,
                 interval_min=event.interval_min,
                 interval_max=event.interval_max,
-                latency=event.latency,
+                max_latency=event.max_latency,
                 timeout=event.timeout,
                 min_ce_length=0,
                 max_ce_length=0,
@@ -604,8 +677,14 @@ class Host(EventEmitter):
                 logger.debug('no long term key provider')
                 long_term_key = None
             else:
-                long_term_key = await self.long_term_key_provider(
+                long_term_key = await self.abort_on(
-                    connection.handle, event.random_number, event.encryption_diversifier
+                    'flush',
+                    # pylint: disable-next=not-callable
+                    self.long_term_key_provider(
+                        connection.handle,
+                        event.random_number,
+                        event.encryption_diversifier,
+                    ),
                 )
             if long_term_key:
                 response = HCI_LE_Long_Term_Key_Request_Reply_Command(
@@ -630,12 +709,14 @@ class Host(EventEmitter):
     def on_hci_role_change_event(self, event):
         if event.status == HCI_SUCCESS:
             logger.debug(
-                f'role change for {event.bd_addr}: {HCI_Constant.role_name(event.new_role)}'
+                f'role change for {event.bd_addr}: '
+                f'{HCI_Constant.role_name(event.new_role)}'
             )
             # TODO: lookup the connection and update the role
         else:
             logger.debug(
-                f'role change for {event.bd_addr} failed: {HCI_Constant.error_name(event.status)}'
+                f'role change for {event.bd_addr} failed: '
+                f'{HCI_Constant.error_name(event.status)}'
             )
 
     def on_hci_le_data_length_change_event(self, event):
@@ -694,17 +775,16 @@ class Host(EventEmitter):
 
     def on_hci_link_key_notification_event(self, event):
         logger.debug(
-            f'link key for {event.bd_addr}: {event.link_key.hex()}, type={HCI_Constant.link_key_type_name(event.key_type)}'
+            f'link key for {event.bd_addr}: {event.link_key.hex()}, '
+            f'type={HCI_Constant.link_key_type_name(event.key_type)}'
         )
         self.emit('link_key', event.bd_addr, event.link_key, event.key_type)
 
     def on_hci_simple_pairing_complete_event(self, event):
         logger.debug(
-            f'simple pairing complete for {event.bd_addr}: status={HCI_Constant.status_name(event.status)}'
+            f'simple pairing complete for {event.bd_addr}: '
+            f'status={HCI_Constant.status_name(event.status)}'
         )
-        # Notify the client
-        if event.status == HCI_SUCCESS:
-            self.emit('ssp_complete', event.bd_addr)
 
     def on_hci_pin_code_request_event(self, event):
         # For now, just refuse all requests
@@ -719,7 +799,11 @@ class Host(EventEmitter):
                 logger.debug('no link key provider')
                 link_key = None
             else:
-                link_key = await self.link_key_provider(event.bd_addr)
+                link_key = await self.abort_on(
+                    'flush',
+                    # pylint: disable-next=not-callable
+                    self.link_key_provider(event.bd_addr),
+                )
             if link_key:
                 response = HCI_Link_Key_Request_Reply_Command(
                     bd_addr=event.bd_addr, link_key=link_key
@@ -754,7 +838,7 @@ class Host(EventEmitter):
             'authentication_user_passkey_notification', event.bd_addr, event.passkey
         )
 
-    def on_hci_inquiry_complete_event(self, event):
+    def on_hci_inquiry_complete_event(self, _event):
         self.emit('inquiry_complete')
 
     def on_hci_inquiry_result_with_rssi_event(self, event):

bumble/keys.py

@@ -24,6 +24,7 @@ import asyncio
 import logging
 import os
 import json
+from typing import Optional
 from colors import color
 
 from .hci import Address
@@ -76,8 +77,10 @@ class PairingKeys:
     @staticmethod
     def key_from_dict(keys_dict, key_name):
         key_dict = keys_dict.get(key_name)
-        if key_dict is not None:
+        if key_dict is None:
-            return PairingKeys.Key.from_dict(key_dict)
+            return None
+
+        return PairingKeys.Key.from_dict(key_dict)
 
     @staticmethod
     def from_dict(keys_dict):
@@ -121,9 +124,9 @@ class PairingKeys:
 
     def print(self, prefix=''):
         keys_dict = self.to_dict()
-        for (property, value) in keys_dict.items():
+        for (container_property, value) in keys_dict.items():
-            if type(value) is dict:
+            if isinstance(value, dict):
-                print(f'{prefix}{color(property, "cyan")}:')
+                print(f'{prefix}{color(container_property, "cyan")}:')
                 for (key_property, key_value) in value.items():
                     print(f'{prefix}  {color(key_property, "green")}: {key_value}')
             else:
@@ -138,7 +141,7 @@ class KeyStore:
     async def update(self, name, keys):
         pass
 
-    async def get(self, name):
+    async def get(self, _name):
         return PairingKeys()
 
     async def get_all(self):
@@ -193,6 +196,9 @@ class JsonKeyStore(KeyStore):
 
         if filename is None:
             # Use a default for the current user
+
+            # Import here because this may not exist on all platforms
+            # pylint: disable=import-outside-toplevel
             import appdirs
 
             self.directory_name = os.path.join(
@@ -219,7 +225,7 @@ class JsonKeyStore(KeyStore):
 
     async def load(self):
         try:
-            with open(self.filename, 'r') as json_file:
+            with open(self.filename, 'r', encoding='utf-8') as json_file:
                 return json.load(json_file)
         except FileNotFoundError:
             return {}
@@ -231,13 +237,13 @@ class JsonKeyStore(KeyStore):
 
         # Save to a temporary file
         temp_filename = self.filename + '.tmp'
-        with open(temp_filename, 'w') as output:
+        with open(temp_filename, 'w', encoding='utf-8') as output:
             json.dump(db, output, sort_keys=True, indent=4)
 
         # Atomically replace the previous file
         os.rename(temp_filename, self.filename)
 
-    async def delete(self, name):
+    async def delete(self, name: str) -> None:
         db = await self.load()
 
         namespace = db.get(self.namespace)
@@ -273,7 +279,7 @@ class JsonKeyStore(KeyStore):
 
         await self.save(db)
 
-    async def get(self, name):
+    async def get(self, name: str) -> Optional[PairingKeys]:
         db = await self.load()
 
         namespace = db.get(self.namespace)

bumble/l2cap.py

@@ -15,6 +15,7 @@
 # -----------------------------------------------------------------------------
 # Imports
 # -----------------------------------------------------------------------------
+from __future__ import annotations
 import asyncio
 import logging
 import struct
@@ -22,6 +23,7 @@ import struct
 from collections import deque
 from colors import color
 from pyee import EventEmitter
+from typing import Dict, Type
 
 from .core import BT_CENTRAL_ROLE, InvalidStateError, ProtocolError
 from .hci import (
@@ -41,6 +43,7 @@ logger = logging.getLogger(__name__)
 # Constants
 # -----------------------------------------------------------------------------
 # fmt: off
+# pylint: disable=line-too-long
 
 L2CAP_SIGNALING_CID    = 0x01
 L2CAP_LE_SIGNALING_CID = 0x05
@@ -137,11 +140,15 @@ L2CAP_MAXIMUM_TRANSMISSION_UNIT_CONFIGURATION_OPTION_TYPE = 0x01
 L2CAP_MTU_CONFIGURATION_PARAMETER_TYPE = 0x01
 
 # fmt: on
+# pylint: enable=line-too-long
 
 
 # -----------------------------------------------------------------------------
 # Classes
 # -----------------------------------------------------------------------------
+# pylint: disable=invalid-name
+
+
 class L2CAP_PDU:
     '''
     See Bluetooth spec @ Vol 3, Part A - 3 DATA PACKET FORMAT
@@ -179,8 +186,9 @@ class L2CAP_Control_Frame:
     See Bluetooth spec @ Vol 3, Part A - 4 SIGNALING PACKET FORMATS
     '''
 
-    classes = {}
+    classes: Dict[int, Type[L2CAP_Control_Frame]] = {}
     code = 0
+    name = None
 
     @staticmethod
     def from_bytes(pdu):
@@ -215,11 +223,11 @@ class L2CAP_Control_Frame:
     def decode_configuration_options(data):
         options = []
         while len(data) >= 2:
-            type = data[0]
+            value_type = data[0]
             length = data[1]
             value = data[2 : 2 + length]
             data = data[2 + length :]
-            options.append((type, value))
+            options.append((value_type, value))
 
         return options
 
@@ -236,7 +244,8 @@ class L2CAP_Control_Frame:
             cls.code = key_with_value(L2CAP_CONTROL_FRAME_NAMES, cls.name)
             if cls.code is None:
                 raise KeyError(
-                    f'Control Frame name {cls.name} not found in L2CAP_CONTROL_FRAME_NAMES'
+                    f'Control Frame name {cls.name} '
+                    'not found in L2CAP_CONTROL_FRAME_NAMES'
                 )
             cls.fields = fields
 
@@ -281,6 +290,7 @@ class L2CAP_Control_Frame:
 
 # -----------------------------------------------------------------------------
 @L2CAP_Control_Frame.subclass(
+    # pylint: disable=unnecessary-lambda
     [
         (
             'reason',
@@ -311,6 +321,7 @@ class L2CAP_Command_Reject(L2CAP_Control_Frame):
 
 # -----------------------------------------------------------------------------
 @L2CAP_Control_Frame.subclass(
+    # pylint: disable=unnecessary-lambda
     [
         (
             'psm',
@@ -356,6 +367,7 @@ class L2CAP_Connection_Request(L2CAP_Control_Frame):
 
 # -----------------------------------------------------------------------------
 @L2CAP_Control_Frame.subclass(
+    # pylint: disable=unnecessary-lambda
     [
         ('destination_cid', 2),
         ('source_cid', 2),
@@ -373,17 +385,18 @@ class L2CAP_Connection_Response(L2CAP_Control_Frame):
 
     CONNECTION_SUCCESSFUL = 0x0000
     CONNECTION_PENDING = 0x0001
-    CONNECTION_REFUSED_LE_PSM_NOT_SUPPORTED = 0x0002
+    CONNECTION_REFUSED_PSM_NOT_SUPPORTED = 0x0002
     CONNECTION_REFUSED_SECURITY_BLOCK = 0x0003
     CONNECTION_REFUSED_NO_RESOURCES_AVAILABLE = 0x0004
     CONNECTION_REFUSED_INVALID_SOURCE_CID = 0x0006
     CONNECTION_REFUSED_SOURCE_CID_ALREADY_ALLOCATED = 0x0007
     CONNECTION_REFUSED_UNACCEPTABLE_PARAMETERS = 0x000B
 
+    # pylint: disable=line-too-long
     RESULT_NAMES = {
         CONNECTION_SUCCESSFUL: 'CONNECTION_SUCCESSFUL',
         CONNECTION_PENDING: 'CONNECTION_PENDING',
-        CONNECTION_REFUSED_LE_PSM_NOT_SUPPORTED: 'CONNECTION_REFUSED_LE_PSM_NOT_SUPPORTED',
+        CONNECTION_REFUSED_PSM_NOT_SUPPORTED: 'CONNECTION_REFUSED_PSM_NOT_SUPPORTED',
         CONNECTION_REFUSED_SECURITY_BLOCK: 'CONNECTION_REFUSED_SECURITY_BLOCK',
         CONNECTION_REFUSED_NO_RESOURCES_AVAILABLE: 'CONNECTION_REFUSED_NO_RESOURCES_AVAILABLE',
         CONNECTION_REFUSED_INVALID_SOURCE_CID: 'CONNECTION_REFUSED_INVALID_SOURCE_CID',
@@ -406,6 +419,7 @@ class L2CAP_Configure_Request(L2CAP_Control_Frame):
 
 # -----------------------------------------------------------------------------
 @L2CAP_Control_Frame.subclass(
+    # pylint: disable=unnecessary-lambda
     [
         ('source_cid', 2),
         ('flags', 2),
@@ -481,6 +495,7 @@ class L2CAP_Echo_Response(L2CAP_Control_Frame):
             'info_type',
             {
                 'size': 2,
+                # pylint: disable-next=unnecessary-lambda
                 'mapper': lambda x: L2CAP_Information_Request.info_type_name(x),
             },
         )
@@ -524,6 +539,7 @@ class L2CAP_Information_Request(L2CAP_Control_Frame):
         ('info_type', {'size': 2, 'mapper': L2CAP_Information_Request.info_type_name}),
         (
             'result',
+            # pylint: disable-next=unnecessary-lambda
             {'size': 2, 'mapper': lambda x: L2CAP_Information_Response.result_name(x)},
         ),
         ('data', '*'),
@@ -568,12 +584,14 @@ class L2CAP_Connection_Parameter_Update_Response(L2CAP_Control_Frame):
 )
 class L2CAP_LE_Credit_Based_Connection_Request(L2CAP_Control_Frame):
     '''
-    See Bluetooth spec @ Vol 3, Part A - 4.22 LE CREDIT BASED CONNECTION REQUEST (CODE 0x14)
+    See Bluetooth spec @ Vol 3, Part A - 4.22 LE CREDIT BASED CONNECTION REQUEST
+    (CODE 0x14)
     '''
 
 
 # -----------------------------------------------------------------------------
 @L2CAP_Control_Frame.subclass(
+    # pylint: disable=unnecessary-lambda,line-too-long
     [
         ('destination_cid', 2),
         ('mtu', 2),
@@ -592,7 +610,8 @@ class L2CAP_LE_Credit_Based_Connection_Request(L2CAP_Control_Frame):
 )
 class L2CAP_LE_Credit_Based_Connection_Response(L2CAP_Control_Frame):
     '''
-    See Bluetooth spec @ Vol 3, Part A - 4.23 LE CREDIT BASED CONNECTION RESPONSE (CODE 0x15)
+    See Bluetooth spec @ Vol 3, Part A - 4.23 LE CREDIT BASED CONNECTION RESPONSE
+    (CODE 0x15)
     '''
 
     CONNECTION_SUCCESSFUL = 0x0000
@@ -606,6 +625,7 @@ class L2CAP_LE_Credit_Based_Connection_Response(L2CAP_Control_Frame):
     CONNECTION_REFUSED_SOURCE_CID_ALREADY_ALLOCATED = 0x000A
     CONNECTION_REFUSED_UNACCEPTABLE_PARAMETERS = 0x000B
 
+    # pylint: disable=line-too-long
     RESULT_NAMES = {
         CONNECTION_SUCCESSFUL: 'CONNECTION_SUCCESSFUL',
         CONNECTION_REFUSED_LE_PSM_NOT_SUPPORTED: 'CONNECTION_REFUSED_LE_PSM_NOT_SUPPORTED',
@@ -693,6 +713,7 @@ class Channel(EventEmitter):
         self.destination_cid = 0
         self.response = None
         self.connection_result = None
+        self.disconnection_result = None
         self.sink = None
 
     def change_state(self, new_state):
@@ -723,6 +744,7 @@ class Channel(EventEmitter):
             self.response.set_result(pdu)
             self.response = None
         elif self.sink:
+            # pylint: disable=not-callable
             self.sink(pdu)
         else:
             logger.warning(
@@ -746,7 +768,8 @@ class Channel(EventEmitter):
             )
         )
 
-        # Create a future to wait for the state machine to get to a success or error state
+        # Create a future to wait for the state machine to get to a success or error
+        # state
         self.connection_result = asyncio.get_running_loop().create_future()
 
         # Wait for the connection to succeed or fail
@@ -768,7 +791,8 @@ class Channel(EventEmitter):
             )
         )
 
-        # Create a future to wait for the state machine to get to a success or error state
+        # Create a future to wait for the state machine to get to a success or error
+        # state
         self.disconnection_result = asyncio.get_running_loop().create_future()
         return await self.disconnection_result
 
@@ -830,10 +854,10 @@ class Channel(EventEmitter):
             self.connection_result = None
 
     def on_configure_request(self, request):
-        if (
+        if self.state not in (
-            self.state != Channel.WAIT_CONFIG
+            Channel.WAIT_CONFIG,
-            and self.state != Channel.WAIT_CONFIG_REQ
+            Channel.WAIT_CONFIG_REQ,
-            and self.state != Channel.WAIT_CONFIG_REQ_RSP
+            Channel.WAIT_CONFIG_REQ_RSP,
         ):
             logger.warning(color('invalid state', 'red'))
             return
@@ -871,10 +895,7 @@ class Channel(EventEmitter):
         if response.result == L2CAP_Configure_Response.SUCCESS:
             if self.state == Channel.WAIT_CONFIG_REQ_RSP:
                 self.change_state(Channel.WAIT_CONFIG_REQ)
-            elif (
+            elif self.state in (Channel.WAIT_CONFIG_RSP, Channel.WAIT_CONTROL_IND):
-                self.state == Channel.WAIT_CONFIG_RSP
-                or self.state == Channel.WAIT_CONTROL_IND
-            ):
                 self.change_state(Channel.OPEN)
                 if self.connection_result:
                     self.connection_result.set_result(None)
@@ -897,14 +918,15 @@ class Channel(EventEmitter):
         else:
             logger.warning(
                 color(
-                    f'!!! configuration rejected: {L2CAP_Configure_Response.result_name(response.result)}',
+                    '!!! configuration rejected: '
+                    f'{L2CAP_Configure_Response.result_name(response.result)}',
                     'red',
                 )
             )
             # TODO: decide how to fail gracefully
 
     def on_disconnection_request(self, request):
-        if self.state == Channel.OPEN or self.state == Channel.WAIT_DISCONNECT:
+        if self.state in (Channel.OPEN, Channel.WAIT_DISCONNECT):
             self.send_control_frame(
                 L2CAP_Disconnection_Response(
                     identifier=request.identifier,
@@ -938,7 +960,12 @@ class Channel(EventEmitter):
         self.manager.on_channel_closed(self)
 
     def __str__(self):
-        return f'Channel({self.source_cid}->{self.destination_cid}, PSM={self.psm}, MTU={self.mtu}, state={Channel.STATE_NAMES[self.state]})'
+        return (
+            f'Channel({self.source_cid}->{self.destination_cid}, '
+            f'PSM={self.psm}, '
+            f'MTU={self.mtu}, '
+            f'state={Channel.STATE_NAMES[self.state]})'
+        )
 
 
 # -----------------------------------------------------------------------------
@@ -976,7 +1003,7 @@ class LeConnectionOrientedChannel(EventEmitter):
         destination_cid,
         mtu,
         mps,
-        credits,
+        credits,  # pylint: disable=redefined-builtin
         peer_mtu,
         peer_mps,
         peer_credits,
@@ -1001,6 +1028,7 @@ class LeConnectionOrientedChannel(EventEmitter):
         self.out_queue = deque()
         self.out_sdu = None
         self.sink = None
+        self.connected = False
         self.connection_result = None
         self.disconnection_result = None
         self.drained = asyncio.Event()
@@ -1072,7 +1100,8 @@ class LeConnectionOrientedChannel(EventEmitter):
             )
         )
 
-        # Create a future to wait for the state machine to get to a success or error state
+        # Create a future to wait for the state machine to get to a success or error
+        # state
         self.disconnection_result = asyncio.get_running_loop().create_future()
         return await self.disconnection_result
 
@@ -1110,7 +1139,8 @@ class LeConnectionOrientedChannel(EventEmitter):
 
         # Check if the SDU is complete
         if self.in_sdu_length == 0:
-            # We don't know the size yet, check if we have received the header to compute it
+            # We don't know the size yet, check if we have received the header to
+            # compute it
             if len(self.in_sdu) >= 2:
                 self.in_sdu_length = struct.unpack_from('<H', self.in_sdu, 0)[0]
         if self.in_sdu_length == 0:
@@ -1125,7 +1155,8 @@ class LeConnectionOrientedChannel(EventEmitter):
         if len(self.in_sdu) != 2 + self.in_sdu_length:
             # Overflow
             logger.warning(
-                f'SDU overflow: sdu_length={self.in_sdu_length}, received {len(self.in_sdu) - 2}'
+                f'SDU overflow: sdu_length={self.in_sdu_length}, '
+                f'received {len(self.in_sdu) - 2}'
             )
             # TODO: we should disconnect
             self.in_sdu = None
@@ -1134,7 +1165,7 @@ class LeConnectionOrientedChannel(EventEmitter):
 
         # Send the SDU to the sink
         logger.debug(f'SDU complete: 2+{len(self.in_sdu) - 2} bytes')
-        self.sink(self.in_sdu[2:])
+        self.sink(self.in_sdu[2:])  # pylint: disable=not-callable
 
         # Prepare for a new SDU
         self.in_sdu = None
@@ -1174,7 +1205,7 @@ class LeConnectionOrientedChannel(EventEmitter):
         # Cleanup
         self.connection_result = None
 
-    def on_credits(self, credits):
+    def on_credits(self, credits):  # pylint: disable=redefined-builtin
         self.credits += credits
         logger.debug(f'received {credits} credits, total = {self.credits}')
 
@@ -1228,7 +1259,8 @@ class LeConnectionOrientedChannel(EventEmitter):
                     # Keep what's still left to send
                     self.out_sdu = self.out_sdu[len(packet) :]
                 continue
-            elif self.out_queue:
+
+            if self.out_queue:
                 # Create the next SDU (2 bytes header plus up to MTU bytes payload)
                 logger.debug(
                     f'assembling SDU from {len(self.out_queue)} packets in output queue'
@@ -1282,13 +1314,20 @@ class LeConnectionOrientedChannel(EventEmitter):
         pass
 
     def __str__(self):
-        return f'CoC({self.source_cid}->{self.destination_cid}, State={self.state_name(self.state)}, PSM={self.le_psm}, MTU={self.mtu}/{self.peer_mtu}, MPS={self.mps}/{self.peer_mps}, credits={self.credits}/{self.peer_credits})'
+        return (
+            f'CoC({self.source_cid}->{self.destination_cid}, '
+            f'State={self.state_name(self.state)}, '
+            f'PSM={self.le_psm}, '
+            f'MTU={self.mtu}/{self.peer_mtu}, '
+            f'MPS={self.mps}/{self.peer_mps}, '
+            f'credits={self.credits}/{self.peer_credits})'
+        )
 
 
 # -----------------------------------------------------------------------------
 class ChannelManager:
     def __init__(
-        self, extended_features=[], connectionless_mtu=L2CAP_DEFAULT_CONNECTIONLESS_MTU
+        self, extended_features=(), connectionless_mtu=L2CAP_DEFAULT_CONNECTIONLESS_MTU
     ):
         self._host = None
         self.identifiers = {}  # Incrementing identifier values by connection
@@ -1322,10 +1361,14 @@ class ChannelManager:
         if connection_channels := self.channels.get(connection_handle):
             return connection_channels.get(cid)
 
+        return None
+
     def find_le_coc_channel(self, connection_handle, cid):
         if connection_channels := self.le_coc_channels.get(connection_handle):
             return connection_channels.get(cid)
 
+        return None
+
     @staticmethod
     def find_free_br_edr_cid(channels):
         # Pick the smallest valid CID that's not already in the list
@@ -1337,6 +1380,8 @@ class ChannelManager:
             if cid not in channels:
                 return cid
 
+        raise RuntimeError('no free CID available')
+
     @staticmethod
     def find_free_le_cid(channels):
         # Pick the smallest valid CID that's not already in the list
@@ -1348,6 +1393,8 @@ class ChannelManager:
             if cid not in channels:
                 return cid
 
+        raise RuntimeError('no free CID')
+
     @staticmethod
     def check_le_coc_parameters(max_credits, mtu, mps):
         if (
@@ -1442,7 +1489,7 @@ class ChannelManager:
 
         return psm
 
-    def on_disconnection(self, connection_handle, reason):
+    def on_disconnection(self, connection_handle, _reason):
         logger.debug(f'disconnection from {connection_handle}, cleaning up channels')
         if connection_handle in self.channels:
             del self.channels[connection_handle]
@@ -1452,14 +1499,16 @@ class ChannelManager:
             del self.identifiers[connection_handle]
 
     def send_pdu(self, connection, cid, pdu):
-        pdu_str = pdu.hex() if type(pdu) is bytes else str(pdu)
+        pdu_str = pdu.hex() if isinstance(pdu, bytes) else str(pdu)
         logger.debug(
-            f'{color(">>> Sending L2CAP PDU", "blue")} on connection [0x{connection.handle:04X}] (CID={cid}) {connection.peer_address}: {pdu_str}'
+            f'{color(">>> Sending L2CAP PDU", "blue")} '
+            f'on connection [0x{connection.handle:04X}] (CID={cid}) '
+            f'{connection.peer_address}: {pdu_str}'
         )
         self.host.send_l2cap_pdu(connection.handle, cid, bytes(pdu))
 
     def on_pdu(self, connection, cid, pdu):
-        if cid == L2CAP_SIGNALING_CID or cid == L2CAP_LE_SIGNALING_CID:
+        if cid in (L2CAP_SIGNALING_CID, L2CAP_LE_SIGNALING_CID):
             # Parse the L2CAP payload into a Control Frame object
             control_frame = L2CAP_Control_Frame.from_bytes(pdu)
 
@@ -1479,13 +1528,17 @@ class ChannelManager:
 
     def send_control_frame(self, connection, cid, control_frame):
         logger.debug(
-            f'{color(">>> Sending L2CAP Signaling Control Frame", "blue")} on connection [0x{connection.handle:04X}] (CID={cid}) {connection.peer_address}:\n{control_frame}'
+            f'{color(">>> Sending L2CAP Signaling Control Frame", "blue")} '
+            f'on connection [0x{connection.handle:04X}] (CID={cid}) '
+            f'{connection.peer_address}:\n{control_frame}'
         )
         self.host.send_l2cap_pdu(connection.handle, cid, bytes(control_frame))
 
     def on_control_frame(self, connection, cid, control_frame):
         logger.debug(
-            f'{color("<<< Received L2CAP Signaling Control Frame", "green")} on connection [0x{connection.handle:04X}] (CID={cid}) {connection.peer_address}:\n{control_frame}'
+            f'{color("<<< Received L2CAP Signaling Control Frame", "green")} '
+            f'on connection [0x{connection.handle:04X}] (CID={cid}) '
+            f'{connection.peer_address}:\n{control_frame}'
         )
 
         # Find the handler method
@@ -1518,7 +1571,7 @@ class ChannelManager:
                 ),
             )
 
-    def on_l2cap_command_reject(self, connection, cid, packet):
+    def on_l2cap_command_reject(self, _connection, _cid, packet):
         logger.warning(f'{color("!!! Command rejected:", "red")} {packet.reason}')
 
     def on_l2cap_connection_request(self, connection, cid, request):
@@ -1536,6 +1589,7 @@ class ChannelManager:
                         identifier=request.identifier,
                         destination_cid=request.source_cid,
                         source_cid=0,
+                        # pylint: disable=line-too-long
                         result=L2CAP_Connection_Response.CONNECTION_REFUSED_NO_RESOURCES_AVAILABLE,
                         status=0x0000,
                     ),
@@ -1556,7 +1610,8 @@ class ChannelManager:
             channel.on_connection_request(request)
         else:
             logger.warning(
-                f'No server for connection 0x{connection.handle:04X} on PSM {request.psm}'
+                f'No server for connection 0x{connection.handle:04X} '
+                f'on PSM {request.psm}'
             )
             self.send_control_frame(
                 connection,
@@ -1565,7 +1620,8 @@ class ChannelManager:
                     identifier=request.identifier,
                     destination_cid=request.source_cid,
                     source_cid=0,
-                    result=L2CAP_Connection_Response.CONNECTION_REFUSED_LE_PSM_NOT_SUPPORTED,
+                    # pylint: disable=line-too-long
+                    result=L2CAP_Connection_Response.CONNECTION_REFUSED_PSM_NOT_SUPPORTED,
                     status=0x0000,
                 ),
             )
@@ -1576,7 +1632,8 @@ class ChannelManager:
         ) is None:
             logger.warning(
                 color(
-                    f'channel {response.source_cid} not found for 0x{connection.handle:04X}:{cid}',
+                    f'channel {response.source_cid} not found for '
+                    f'0x{connection.handle:04X}:{cid}',
                     'red',
                 )
             )
@@ -1590,7 +1647,8 @@ class ChannelManager:
         ) is None:
             logger.warning(
                 color(
-                    f'channel {request.destination_cid} not found for 0x{connection.handle:04X}:{cid}',
+                    f'channel {request.destination_cid} not found for '
+                    f'0x{connection.handle:04X}:{cid}',
                     'red',
                 )
             )
@@ -1604,7 +1662,8 @@ class ChannelManager:
         ) is None:
             logger.warning(
                 color(
-                    f'channel {response.source_cid} not found for 0x{connection.handle:04X}:{cid}',
+                    f'channel {response.source_cid} not found for '
+                    f'0x{connection.handle:04X}:{cid}',
                     'red',
                 )
             )
@@ -1618,7 +1677,8 @@ class ChannelManager:
         ) is None:
             logger.warning(
                 color(
-                    f'channel {request.destination_cid} not found for 0x{connection.handle:04X}:{cid}',
+                    f'channel {request.destination_cid} not found for '
+                    f'0x{connection.handle:04X}:{cid}',
                     'red',
                 )
             )
@@ -1632,7 +1692,8 @@ class ChannelManager:
         ) is None:
             logger.warning(
                 color(
-                    f'channel {response.source_cid} not found for 0x{connection.handle:04X}:{cid}',
+                    f'channel {response.source_cid} not found for '
+                    f'0x{connection.handle:04X}:{cid}',
                     'red',
                 )
             )
@@ -1648,7 +1709,7 @@ class ChannelManager:
             L2CAP_Echo_Response(identifier=request.identifier, data=request.data),
         )
 
-    def on_l2cap_echo_response(self, connection, cid, response):
+    def on_l2cap_echo_response(self, _connection, _cid, response):
         logger.debug(f'<<< Echo response: data={response.data.hex()}')
         # TODO notify listeners
 
@@ -1663,7 +1724,7 @@ class ChannelManager:
             result = L2CAP_Information_Response.SUCCESS
             data = sum(1 << cid for cid in self.fixed_channels).to_bytes(8, 'little')
         else:
-            result = L2CAP_Information_Request.NO_SUPPORTED
+            result = L2CAP_Information_Response.NOT_SUPPORTED
 
         self.send_control_frame(
             connection,
@@ -1730,6 +1791,7 @@ class ChannelManager:
                         mtu=mtu,
                         mps=mps,
                         initial_credits=0,
+                        # pylint: disable=line-too-long
                         result=L2CAP_LE_Credit_Based_Connection_Response.CONNECTION_REFUSED_SOURCE_CID_ALREADY_ALLOCATED,
                     ),
                 )
@@ -1748,6 +1810,7 @@ class ChannelManager:
                         mtu=mtu,
                         mps=mps,
                         initial_credits=0,
+                        # pylint: disable=line-too-long
                         result=L2CAP_LE_Credit_Based_Connection_Response.CONNECTION_REFUSED_NO_RESOURCES_AVAILABLE,
                     ),
                 )
@@ -1755,7 +1818,8 @@ class ChannelManager:
 
             # Create a new channel
             logger.debug(
-                f'creating LE CoC server channel with cid={source_cid} for psm {request.le_psm}'
+                f'creating LE CoC server channel with cid={source_cid} for psm '
+                f'{request.le_psm}'
             )
             channel = LeConnectionOrientedChannel(
                 self,
@@ -1784,6 +1848,7 @@ class ChannelManager:
                     mtu=mtu,
                     mps=mps,
                     initial_credits=max_credits,
+                    # pylint: disable=line-too-long
                     result=L2CAP_LE_Credit_Based_Connection_Response.CONNECTION_SUCCESSFUL,
                 ),
             )
@@ -1792,7 +1857,8 @@ class ChannelManager:
             server(channel)
         else:
             logger.info(
-                f'No LE server for connection 0x{connection.handle:04X} on PSM {request.le_psm}'
+                f'No LE server for connection 0x{connection.handle:04X} '
+                f'on PSM {request.le_psm}'
             )
             self.send_control_frame(
                 connection,
@@ -1803,11 +1869,12 @@ class ChannelManager:
                     mtu=L2CAP_LE_CREDIT_BASED_CONNECTION_DEFAULT_MTU,
                     mps=L2CAP_LE_CREDIT_BASED_CONNECTION_DEFAULT_MPS,
                     initial_credits=0,
+                    # pylint: disable=line-too-long
                     result=L2CAP_LE_Credit_Based_Connection_Response.CONNECTION_REFUSED_LE_PSM_NOT_SUPPORTED,
                 ),
             )
 
-    def on_l2cap_le_credit_based_connection_response(self, connection, cid, response):
+    def on_l2cap_le_credit_based_connection_response(self, connection, _cid, response):
         # Find the pending request by identifier
         request = self.le_coc_requests.get(response.identifier)
         if request is None:
@@ -1820,7 +1887,8 @@ class ChannelManager:
         if channel is None:
             logger.warning(
                 color(
-                    f'received connection response for an unknown channel (cid={request.source_cid})',
+                    'received connection response for an unknown channel '
+                    f'(cid={request.source_cid})',
                     'red',
                 )
             )
@@ -1829,7 +1897,7 @@ class ChannelManager:
         # Process the response
         channel.on_connection_response(response)
 
-    def on_l2cap_le_flow_control_credit(self, connection, cid, credit):
+    def on_l2cap_le_flow_control_credit(self, connection, _cid, credit):
         channel = self.find_le_coc_channel(connection.handle, credit.cid)
         if channel is None:
             logger.warning(f'received credits for an unknown channel (cid={credit.cid}')

bumble/link.py

@@ -17,9 +17,10 @@
 # -----------------------------------------------------------------------------
 import logging
 import asyncio
-import websockets
 from functools import partial
+
 from colors import color
+import websockets
 
 from bumble.hci import (
     Address,
@@ -47,7 +48,8 @@ def parse_parameters(params_str):
 
 
 # -----------------------------------------------------------------------------
-# TODO: add more support for various LL exchanges (see Vol 6, Part B - 2.4 DATA CHANNEL PDU)
+# TODO: add more support for various LL exchanges
+# (see Vol 6, Part B - 2.4 DATA CHANNEL PDU)
 # -----------------------------------------------------------------------------
 class LocalLink:
     '''
@@ -119,7 +121,8 @@ class LocalLink:
 
     def connect(self, central_address, le_create_connection_command):
         logger.debug(
-            f'$$$ CONNECTION {central_address} -> {le_create_connection_command.peer_address}'
+            f'$$$ CONNECTION {central_address} -> '
+            f'{le_create_connection_command.peer_address}'
         )
         self.pending_connection = (central_address, le_create_connection_command)
         asyncio.get_running_loop().call_soon(self.on_connection_complete)
@@ -144,11 +147,13 @@ class LocalLink:
 
     def disconnect(self, central_address, peripheral_address, disconnect_command):
         logger.debug(
-            f'$$$ DISCONNECTION {central_address} -> {peripheral_address}: reason = {disconnect_command.reason}'
+            f'$$$ DISCONNECTION {central_address} -> '
+            f'{peripheral_address}: reason = {disconnect_command.reason}'
         )
         args = [central_address, peripheral_address, disconnect_command]
         asyncio.get_running_loop().call_soon(self.on_disconnection_complete, *args)
 
+    # pylint: disable=too-many-arguments
     def on_connection_encrypted(
         self, central_address, peripheral_address, rand, ediv, ltk
     ):
@@ -217,6 +222,7 @@ class RemoteLink:
     async def run_connection(self):
         # Connect to the relay
         logger.debug(f'connecting to {self.uri}')
+        # pylint: disable-next=no-member
         websocket = await websockets.connect(self.uri)
         self.websocket.set_result(websocket)
         logger.debug(f'connected to {self.uri}')
@@ -287,11 +293,11 @@ class RemoteLink:
         self.controller.on_link_central_connected(Address(sender))
 
         # Accept the connection by responding to it
-        await self.send_targetted_message(sender, 'connected')
+        await self.send_targeted_message(sender, 'connected')
 
     async def on_connected_message_received(self, sender, _):
         if not self.pending_connection:
-            logger.warn('received a connection ack, but no connection is pending')
+            logger.warning('received a connection ack, but no connection is pending')
             return
 
         # Remember the connection
@@ -313,7 +319,7 @@ class RemoteLink:
         if sender in self.peripheral_connections:
             self.peripheral_connections.remove(sender)
 
-    async def on_encrypted_message_received(self, sender, message):
+    async def on_encrypted_message_received(self, sender, _):
         # TODO parse params to get real args
         self.controller.on_link_encrypted(Address(sender), bytes(8), 0, bytes(16))
 
@@ -335,7 +341,7 @@ class RemoteLink:
 
         # TODO: parse the result
 
-    async def send_targetted_message(self, target, message):
+    async def send_targeted_message(self, target, message):
         # Ensure we have a connection
         websocket = await self.websocket
 
@@ -352,23 +358,23 @@ class RemoteLink:
         self.execute(self.notify_address_changed)
 
     async def send_advertising_data_to_relay(self, data):
-        await self.send_targetted_message('*', f'advertisement:{data.hex()}')
+        await self.send_targeted_message('*', f'advertisement:{data.hex()}')
 
-    def send_advertising_data(self, sender_address, data):
+    def send_advertising_data(self, _, data):
         self.execute(partial(self.send_advertising_data_to_relay, data))
 
     async def send_acl_data_to_relay(self, peer_address, data):
-        await self.send_targetted_message(peer_address, f'acl:{data.hex()}')
+        await self.send_targeted_message(peer_address, f'acl:{data.hex()}')
 
-    def send_acl_data(self, sender_address, peer_address, data):
+    def send_acl_data(self, _, peer_address, data):
         self.execute(partial(self.send_acl_data_to_relay, peer_address, data))
 
     async def send_connection_request_to_relay(self, peer_address):
-        await self.send_targetted_message(peer_address, 'connect')
+        await self.send_targeted_message(peer_address, 'connect')
 
-    def connect(self, central_address, le_create_connection_command):
+    def connect(self, _, le_create_connection_command):
         if self.pending_connection:
-            logger.warn('connection already pending')
+            logger.warning('connection already pending')
             return
         self.pending_connection = le_create_connection_command
         self.execute(
@@ -385,11 +391,12 @@ class RemoteLink:
 
     def disconnect(self, central_address, peripheral_address, disconnect_command):
         logger.debug(
-            f'disconnect {central_address} -> {peripheral_address}: reason = {disconnect_command.reason}'
+            f'disconnect {central_address} -> '
+            f'{peripheral_address}: reason = {disconnect_command.reason}'
         )
         self.execute(
             partial(
-                self.send_targetted_message,
+                self.send_targeted_message,
                 peripheral_address,
                 f'disconnect:reason={disconnect_command.reason}',
             )
@@ -398,15 +405,13 @@ class RemoteLink:
             self.on_disconnection_complete, disconnect_command
         )
 
-    def on_connection_encrypted(
+    def on_connection_encrypted(self, _, peripheral_address, rand, ediv, ltk):
-        self, central_address, peripheral_address, rand, ediv, ltk
-    ):
         asyncio.get_running_loop().call_soon(
             self.controller.on_link_encrypted, peripheral_address, rand, ediv, ltk
         )
         self.execute(
             partial(
-                self.send_targetted_message,
+                self.send_targeted_message,
                 peripheral_address,
                 f'encrypted:ltk={ltk.hex()}',
             )

bumble/profiles/asha_service.py

@@ -18,6 +18,7 @@
 # -----------------------------------------------------------------------------
 import struct
 import logging
+from typing import List
 from ..core import AdvertisingData
 from ..gatt import (
     GATT_ASHA_SERVICE,
@@ -29,8 +30,8 @@ from ..gatt import (
     TemplateService,
     Characteristic,
     CharacteristicValue,
-    PackedCharacteristicAdapter,
 )
+from ..device import Device
 
 # -----------------------------------------------------------------------------
 # Logging
@@ -50,23 +51,30 @@ class AshaService(TemplateService):
     SUPPORTED_CODEC_ID = [0x02, 0x01]  # Codec IDs [G.722 at 16 kHz]
     RENDER_DELAY = [00, 00]
 
-    def __init__(self, capability: int, hisyncid: [int]):
+    def __init__(self, capability: int, hisyncid: List[int], device: Device, psm=0):
         self.hisyncid = hisyncid
         self.capability = capability  # Device Capabilities [Left, Monaural]
+        self.device = device
+        self.emitted_data_name = 'ASHA_data_' + str(self.capability)
+        self.audio_out_data = b''
+        self.psm = psm  # a non-zero psm is mainly for testing purpose
 
         # Handler for volume control
-        def on_volume_write(connection, value):
+        def on_volume_write(_connection, value):
             logger.info(f'--- VOLUME Write:{value[0]}')
 
         # Handler for audio control commands
-        def on_audio_control_point_write(connection, value):
+        def on_audio_control_point_write(_connection, value):
             logger.info(f'--- AUDIO CONTROL POINT Write:{value.hex()}')
             opcode = value[0]
             if opcode == AshaService.OPCODE_START:
                 # Start
                 audio_type = ('Unknown', 'Ringtone', 'Phone Call', 'Media')[value[2]]
                 logger.info(
-                    f'### START: codec={value[1]}, audio_type={audio_type}, volume={value[3]}, otherstate={value[4]}'
+                    f'### START: codec={value[1]}, '
+                    f'audio_type={audio_type}, '
+                    f'volume={value[3]}, '
+                    f'otherstate={value[4]}'
                 )
             elif opcode == AshaService.OPCODE_STOP:
                 logger.info('### STOP')
@@ -74,7 +82,8 @@ class AshaService(TemplateService):
                 logger.info(f'### STATUS: connected={value[1]}')
 
             # TODO Respond with a status
-            # asyncio.create_task(device.notify_subscribers(audio_status_characteristic, force=True))
+            # asyncio.create_task(device.notify_subscribers(audio_status_characteristic,
+            # force=True))
 
         self.read_only_properties_characteristic = Characteristic(
             GATT_ASHA_READ_ONLY_PROPERTIES_CHARACTERISTIC,
@@ -112,9 +121,18 @@ class AshaService(TemplateService):
             CharacteristicValue(write=on_volume_write),
         )
 
-        # TODO add real psm value
+        # Register an L2CAP CoC server
-        self.psm = 0x0080
+        def on_coc(channel):
-        # self.psm = device.register_l2cap_channel_server(0, on_coc, 8)
+            def on_data(data):
+                logging.debug(f'<<< data received:{data}')
+
+                self.emit(self.emitted_data_name, data)
+                self.audio_out_data += data
+
+            channel.sink = on_data
+
+        # let the server find a free PSM
+        self.psm = self.device.register_l2cap_channel_server(self.psm, on_coc, 8)
         self.le_psm_out_characteristic = Characteristic(
             GATT_ASHA_LE_PSM_OUT_CHARACTERISTIC,
             Characteristic.READ,
@@ -137,10 +155,6 @@ class AshaService(TemplateService):
         return bytes(
             AdvertisingData(
                 [
-                    (
-                        AdvertisingData.INCOMPLETE_LIST_OF_16_BIT_SERVICE_CLASS_UUIDS,
-                        bytes(GATT_ASHA_SERVICE),
-                    ),
                     (
                         AdvertisingData.SERVICE_DATA_16_BIT_UUID,
                         bytes(GATT_ASHA_SERVICE)

bumble/profiles/battery_service.py

@@ -40,7 +40,7 @@ class BatteryService(TemplateService):
                 Characteristic.READABLE,
                 CharacteristicValue(read=read_battery_level),
             ),
-            format=BatteryService.BATTERY_LEVEL_FORMAT,
+            pack_format=BatteryService.BATTERY_LEVEL_FORMAT,
         )
         super().__init__([self.battery_level_characteristic])
 
@@ -56,7 +56,7 @@ class BatteryServiceProxy(ProfileServiceProxy):
             GATT_BATTERY_LEVEL_CHARACTERISTIC
         ):
             self.battery_level = PackedCharacteristicAdapter(
-                characteristics[0], format=BatteryService.BATTERY_LEVEL_FORMAT
+                characteristics[0], pack_format=BatteryService.BATTERY_LEVEL_FORMAT
             )
         else:
             self.battery_level = None

bumble/profiles/device_information_service.py

@@ -17,7 +17,7 @@
 # Imports
 # -----------------------------------------------------------------------------
 import struct
-from typing import Tuple
+from typing import Optional, Tuple
 
 from ..gatt_client import ProfileServiceProxy
 from ..gatt import (
@@ -52,14 +52,14 @@ class DeviceInformationService(TemplateService):
 
     def __init__(
         self,
-        manufacturer_name: str = None,
+        manufacturer_name: Optional[str] = None,
-        model_number: str = None,
+        model_number: Optional[str] = None,
-        serial_number: str = None,
+        serial_number: Optional[str] = None,
-        hardware_revision: str = None,
+        hardware_revision: Optional[str] = None,
-        firmware_revision: str = None,
+        firmware_revision: Optional[str] = None,
-        software_revision: str = None,
+        software_revision: Optional[str] = None,
-        system_id: Tuple[int, int] = None,  # (OUI, Manufacturer ID)
+        system_id: Optional[Tuple[int, int]] = None,  # (OUI, Manufacturer ID)
-        ieee_regulatory_certification_data_list: bytes = None
+        ieee_regulatory_certification_data_list: Optional[bytes] = None
         # TODO: pnp_id
     ):
         characteristics = [

bumble/profiles/heart_rate_service.py

@@ -156,6 +156,7 @@ class HeartRateService(TemplateService):
                 0,
                 CharacteristicValue(read=read_heart_rate_measurement),
             ),
+            # pylint: disable=unnecessary-lambda
             encode=lambda value: bytes(value),
         )
         characteristics = [self.heart_rate_measurement_characteristic]
@@ -185,7 +186,7 @@ class HeartRateService(TemplateService):
                     Characteristic.WRITEABLE,
                     CharacteristicValue(write=write_heart_rate_control_point_value),
                 ),
-                format=HeartRateService.HEART_RATE_CONTROL_POINT_FORMAT,
+                pack_format=HeartRateService.HEART_RATE_CONTROL_POINT_FORMAT,
             )
             characteristics.append(self.heart_rate_control_point_characteristic)
 
@@ -224,7 +225,7 @@ class HeartRateServiceProxy(ProfileServiceProxy):
         ):
             self.heart_rate_control_point = PackedCharacteristicAdapter(
                 characteristics[0],
-                format=HeartRateService.HEART_RATE_CONTROL_POINT_FORMAT,
+                pack_format=HeartRateService.HEART_RATE_CONTROL_POINT_FORMAT,
             )
         else:
             self.heart_rate_control_point = None

bumble/rfcomm.py

@@ -21,7 +21,8 @@ import asyncio
 from colors import color
 from pyee import EventEmitter
 
-from .core import BT_BR_EDR_TRANSPORT, InvalidStateError, ProtocolError, ConnectionError
+from . import core
+from .core import BT_BR_EDR_TRANSPORT, InvalidStateError, ProtocolError
 
 # -----------------------------------------------------------------------------
 # Logging
@@ -104,17 +105,17 @@ RFCOMM_DYNAMIC_CHANNEL_NUMBER_END   = 30
 
 
 # -----------------------------------------------------------------------------
-def fcs(buffer):
+def compute_fcs(buffer):
-    fcs = 0xFF
+    result = 0xFF
     for byte in buffer:
-        fcs = CRC_TABLE[fcs ^ byte]
+        result = CRC_TABLE[result ^ byte]
-    return 0xFF - fcs
+    return 0xFF - result
 
 
 # -----------------------------------------------------------------------------
 class RFCOMM_Frame:
-    def __init__(self, type, c_r, dlci, p_f, information=b'', with_credits=False):
+    def __init__(self, frame_type, c_r, dlci, p_f, information=b'', with_credits=False):
-        self.type = type
+        self.type = frame_type
         self.c_r = c_r
         self.dlci = dlci
         self.p_f = p_f
@@ -129,18 +130,18 @@ class RFCOMM_Frame:
             # 1-byte length indicator
             self.length = bytes([(length << 1) | 1])
         self.address = (dlci << 2) | (c_r << 1) | 1
-        self.control = type | (p_f << 4)
+        self.control = frame_type | (p_f << 4)
-        if type == RFCOMM_UIH_FRAME:
+        if frame_type == RFCOMM_UIH_FRAME:
-            self.fcs = fcs(bytes([self.address, self.control]))
+            self.fcs = compute_fcs(bytes([self.address, self.control]))
         else:
-            self.fcs = fcs(bytes([self.address, self.control]) + self.length)
+            self.fcs = compute_fcs(bytes([self.address, self.control]) + self.length)
 
     def type_name(self):
         return RFCOMM_FRAME_TYPE_NAMES[self.type]
 
     @staticmethod
     def parse_mcc(data):
-        type = data[0] >> 2
+        mcc_type = data[0] >> 2
         c_r = (data[0] >> 1) & 1
         length = data[1]
         if data[1] & 1:
@@ -150,12 +151,12 @@ class RFCOMM_Frame:
             length = (data[3] << 7) & (length >> 1)
             value = data[3 : 3 + length]
 
-        return (type, c_r, value)
+        return (mcc_type, c_r, value)
 
     @staticmethod
-    def make_mcc(type, c_r, data):
+    def make_mcc(mcc_type, c_r, data):
         return (
-            bytes([(type << 2 | c_r << 1 | 1) & 0xFF, (len(data) & 0x7F) << 1 | 1])
+            bytes([(mcc_type << 2 | c_r << 1 | 1) & 0xFF, (len(data) & 0x7F) << 1 | 1])
             + data
         )
 
@@ -186,7 +187,7 @@ class RFCOMM_Frame:
         # Extract fields
         dlci = (data[0] >> 2) & 0x3F
         c_r = (data[0] >> 1) & 0x01
-        type = data[1] & 0xEF
+        frame_type = data[1] & 0xEF
         p_f = (data[1] >> 4) & 0x01
         length = data[2]
         if length & 0x01:
@@ -198,9 +199,9 @@ class RFCOMM_Frame:
         fcs = data[-1]
 
         # Construct the frame and check the CRC
-        frame = RFCOMM_Frame(type, c_r, dlci, p_f, information)
+        frame = RFCOMM_Frame(frame_type, c_r, dlci, p_f, information)
         if frame.fcs != fcs:
-            logger.warn(f'FCS mismatch: got {fcs:02X}, expected {frame.fcs:02X}')
+            logger.warning(f'FCS mismatch: got {fcs:02X}, expected {frame.fcs:02X}')
             raise ValueError('fcs mismatch')
 
         return frame
@@ -214,7 +215,14 @@ class RFCOMM_Frame:
         )
 
     def __str__(self):
-        return f'{color(self.type_name(), "yellow")}(c/r={self.c_r},dlci={self.dlci},p/f={self.p_f},length={len(self.information)},fcs=0x{self.fcs:02X})'
+        return (
+            f'{color(self.type_name(), "yellow")}'
+            f'(c/r={self.c_r},'
+            f'dlci={self.dlci},'
+            f'p/f={self.p_f},'
+            f'length={len(self.information)},'
+            f'fcs=0x{self.fcs:02X})'
+        )
 
 
 # -----------------------------------------------------------------------------
@@ -264,7 +272,15 @@ class RFCOMM_MCC_PN:
         )
 
     def __str__(self):
-        return f'PN(dlci={self.dlci},cl={self.cl},priority={self.priority},ack_timer={self.ack_timer},max_frame_size={self.max_frame_size},max_retransmissions={self.max_retransmissions},window_size={self.window_size})'
+        return (
+            f'PN(dlci={self.dlci},'
+            f'cl={self.cl},'
+            f'priority={self.priority},'
+            f'ack_timer={self.ack_timer},'
+            f'max_frame_size={self.max_frame_size},'
+            f'max_retransmissions={self.max_retransmissions},'
+            f'window_size={self.window_size})'
+        )
 
 
 # -----------------------------------------------------------------------------
@@ -302,7 +318,14 @@ class RFCOMM_MCC_MSC:
         )
 
     def __str__(self):
-        return f'MSC(dlci={self.dlci},fc={self.fc},rtc={self.rtc},rtr={self.rtr},ic={self.ic},dv={self.dv})'
+        return (
+            f'MSC(dlci={self.dlci},'
+            f'fc={self.fc},'
+            f'rtc={self.rtc},'
+            f'rtr={self.rtr},'
+            f'ic={self.ic},'
+            f'dv={self.dv})'
+        )
 
 
 # -----------------------------------------------------------------------------
@@ -336,6 +359,7 @@ class DLC(EventEmitter):
         self.role = multiplexer.role
         self.c_r = 1 if self.role == Multiplexer.INITIATOR else 0
         self.sink = None
+        self.connection_result = None
 
         # Compute the MTU
         max_overhead = 4 + 1  # header with 2-byte length + fcs
@@ -360,30 +384,38 @@ class DLC(EventEmitter):
         handler = getattr(self, f'on_{frame.type_name()}_frame'.lower())
         handler(frame)
 
-    def on_sabm_frame(self, frame):
+    def on_sabm_frame(self, _frame):
         if self.state != DLC.CONNECTING:
-            logger.warn(color('!!! received SABM when not in CONNECTING state', 'red'))
+            logger.warning(
+                color('!!! received SABM when not in CONNECTING state', 'red')
+            )
             return
 
         self.send_frame(RFCOMM_Frame.ua(c_r=1 - self.c_r, dlci=self.dlci))
 
         # Exchange the modem status with the peer
         msc = RFCOMM_MCC_MSC(dlci=self.dlci, fc=0, rtc=1, rtr=1, ic=0, dv=1)
-        mcc = RFCOMM_Frame.make_mcc(type=RFCOMM_MCC_MSC_TYPE, c_r=1, data=bytes(msc))
+        mcc = RFCOMM_Frame.make_mcc(
+            mcc_type=RFCOMM_MCC_MSC_TYPE, c_r=1, data=bytes(msc)
+        )
         logger.debug(f'>>> MCC MSC Command: {msc}')
         self.send_frame(RFCOMM_Frame.uih(c_r=self.c_r, dlci=0, information=mcc))
 
         self.change_state(DLC.CONNECTED)
         self.emit('open')
 
-    def on_ua_frame(self, frame):
+    def on_ua_frame(self, _frame):
         if self.state != DLC.CONNECTING:
-            logger.warn(color('!!! received SABM when not in CONNECTING state', 'red'))
+            logger.warning(
+                color('!!! received SABM when not in CONNECTING state', 'red')
+            )
             return
 
         # Exchange the modem status with the peer
         msc = RFCOMM_MCC_MSC(dlci=self.dlci, fc=0, rtc=1, rtr=1, ic=0, dv=1)
-        mcc = RFCOMM_Frame.make_mcc(type=RFCOMM_MCC_MSC_TYPE, c_r=1, data=bytes(msc))
+        mcc = RFCOMM_Frame.make_mcc(
+            mcc_type=RFCOMM_MCC_MSC_TYPE, c_r=1, data=bytes(msc)
+        )
         logger.debug(f'>>> MCC MSC Command: {msc}')
         self.send_frame(RFCOMM_Frame.uih(c_r=self.c_r, dlci=0, information=mcc))
 
@@ -394,7 +426,7 @@ class DLC(EventEmitter):
         # TODO: handle all states
         pass
 
-    def on_disc_frame(self, frame):
+    def on_disc_frame(self, _frame):
         # TODO: handle all states
         self.send_frame(RFCOMM_Frame.ua(c_r=1 - self.c_r, dlci=self.dlci))
 
@@ -402,25 +434,28 @@ class DLC(EventEmitter):
         data = frame.information
         if frame.p_f == 1:
             # With credits
-            credits = frame.information[0]
+            received_credits = frame.information[0]
-            self.tx_credits += credits
+            self.tx_credits += received_credits
 
             logger.debug(
-                f'<<< Credits [{self.dlci}]: received {credits}, total={self.tx_credits}'
+                f'<<< Credits [{self.dlci}]: '
+                f'received {credits}, total={self.tx_credits}'
             )
             data = data[1:]
 
         logger.debug(
-            f'{color("<<< Data", "yellow")} [{self.dlci}] {len(data)} bytes, rx_credits={self.rx_credits}: {data.hex()}'
+            f'{color("<<< Data", "yellow")} '
+            f'[{self.dlci}] {len(data)} bytes, '
+            f'rx_credits={self.rx_credits}: {data.hex()}'
         )
         if len(data) and self.sink:
-            self.sink(data)
+            self.sink(data)  # pylint: disable=not-callable
 
         # Update the credits
         if self.rx_credits > 0:
             self.rx_credits -= 1
         else:
-            logger.warn(color('!!! received frame with no rx credits', 'red'))
+            logger.warning(color('!!! received frame with no rx credits', 'red'))
 
         # Check if there's anything to send (including credits)
         self.process_tx()
@@ -434,7 +469,7 @@ class DLC(EventEmitter):
             logger.debug(f'<<< MCC MSC Command: {msc}')
             msc = RFCOMM_MCC_MSC(dlci=self.dlci, fc=0, rtc=1, rtr=1, ic=0, dv=1)
             mcc = RFCOMM_Frame.make_mcc(
-                type=RFCOMM_MCC_MSC_TYPE, c_r=0, data=bytes(msc)
+                mcc_type=RFCOMM_MCC_MSC_TYPE, c_r=0, data=bytes(msc)
             )
             logger.debug(f'>>> MCC MSC Response: {msc}')
             self.send_frame(RFCOMM_Frame.uih(c_r=self.c_r, dlci=0, information=mcc))
@@ -443,7 +478,7 @@ class DLC(EventEmitter):
             logger.debug(f'<<< MCC MSC Response: {msc}')
 
     def connect(self):
-        if not self.state == DLC.INIT:
+        if self.state != DLC.INIT:
             raise InvalidStateError('invalid state')
 
         self.change_state(DLC.CONNECTING)
@@ -451,7 +486,7 @@ class DLC(EventEmitter):
         self.send_frame(RFCOMM_Frame.sabm(c_r=self.c_r, dlci=self.dlci))
 
     def accept(self):
-        if not self.state == DLC.INIT:
+        if self.state != DLC.INIT:
             raise InvalidStateError('invalid state')
 
         pn = RFCOMM_MCC_PN(
@@ -463,7 +498,7 @@ class DLC(EventEmitter):
             max_retransmissions=0,
             window_size=RFCOMM_DEFAULT_INITIAL_RX_CREDITS,
         )
-        mcc = RFCOMM_Frame.make_mcc(type=RFCOMM_MCC_PN_TYPE, c_r=0, data=bytes(pn))
+        mcc = RFCOMM_Frame.make_mcc(mcc_type=RFCOMM_MCC_PN_TYPE, c_r=0, data=bytes(pn))
         logger.debug(f'>>> PN Response: {pn}')
         self.send_frame(RFCOMM_Frame.uih(c_r=self.c_r, dlci=0, information=mcc))
         self.change_state(DLC.CONNECTING)
@@ -471,8 +506,8 @@ class DLC(EventEmitter):
     def rx_credits_needed(self):
         if self.rx_credits <= self.rx_threshold:
             return RFCOMM_DEFAULT_INITIAL_RX_CREDITS - self.rx_credits
-        else:
+
-            return 0
+        return 0
 
     def process_tx(self):
         # Send anything we can (or an empty frame if we need to send rx credits)
@@ -496,7 +531,9 @@ class DLC(EventEmitter):
 
             # Send the frame
             logger.debug(
-                f'>>> sending {len(chunk)} bytes with {rx_credits_needed} credits, rx_credits={self.rx_credits}, tx_credits={self.tx_credits}'
+                f'>>> sending {len(chunk)} bytes with {rx_credits_needed} credits, '
+                f'rx_credits={self.rx_credits}, '
+                f'tx_credits={self.tx_credits}'
             )
             self.send_frame(
                 RFCOMM_Frame.uih(
@@ -512,8 +549,8 @@ class DLC(EventEmitter):
     # Stream protocol
     def write(self, data):
         # We can only send bytes
-        if type(data) != bytes:
+        if not isinstance(data, bytes):
-            if type(data) == str:
+            if isinstance(data, str):
                 # Automatically convert strings to bytes using UTF-8
                 data = data.encode('utf-8')
             else:
@@ -592,14 +629,14 @@ class Multiplexer(EventEmitter):
             self.on_frame(frame)
         else:
             if frame.type == RFCOMM_DM_FRAME:
-                # DM responses are for a DLCI, but since we only create the dlc when we receive
+                # DM responses are for a DLCI, but since we only create the dlc when we
-                # a PN response (because we need the parameters), we handle DM frames at the Multiplexer
+                # receive a PN response (because we need the parameters), we handle DM
-                # level
+                # frames at the Multiplexer level
                 self.on_dm_frame(frame)
             else:
                 dlc = self.dlcs.get(frame.dlci)
                 if dlc is None:
-                    logger.warn(f'no dlc for DLCI {frame.dlci}')
+                    logger.warning(f'no dlc for DLCI {frame.dlci}')
                     return
                 dlc.on_frame(frame)
 
@@ -607,14 +644,14 @@ class Multiplexer(EventEmitter):
         handler = getattr(self, f'on_{frame.type_name()}_frame'.lower())
         handler(frame)
 
-    def on_sabm_frame(self, frame):
+    def on_sabm_frame(self, _frame):
         if self.state != Multiplexer.INIT:
             logger.debug('not in INIT state, ignoring SABM')
             return
         self.change_state(Multiplexer.CONNECTED)
         self.send_frame(RFCOMM_Frame.ua(c_r=1, dlci=0))
 
-    def on_ua_frame(self, frame):
+    def on_ua_frame(self, _frame):
         if self.state == Multiplexer.CONNECTING:
             self.change_state(Multiplexer.CONNECTED)
             if self.connection_result:
@@ -626,34 +663,34 @@ class Multiplexer(EventEmitter):
                 self.disconnection_result.set_result(None)
                 self.disconnection_result = None
 
-    def on_dm_frame(self, frame):
+    def on_dm_frame(self, _frame):
         if self.state == Multiplexer.OPENING:
             self.change_state(Multiplexer.CONNECTED)
             if self.open_result:
                 self.open_result.set_exception(
-                    ConnectionError(
+                    core.ConnectionError(
-                        ConnectionError.CONNECTION_REFUSED,
+                        core.ConnectionError.CONNECTION_REFUSED,
                         BT_BR_EDR_TRANSPORT,
                         self.l2cap_channel.connection.peer_address,
                         'rfcomm',
                     )
                 )
         else:
-            logger.warn(f'unexpected state for DM: {self}')
+            logger.warning(f'unexpected state for DM: {self}')
 
-    def on_disc_frame(self, frame):
+    def on_disc_frame(self, _frame):
         self.change_state(Multiplexer.DISCONNECTED)
         self.send_frame(
             RFCOMM_Frame.ua(c_r=0 if self.role == Multiplexer.INITIATOR else 1, dlci=0)
         )
 
     def on_uih_frame(self, frame):
-        (type, c_r, value) = RFCOMM_Frame.parse_mcc(frame.information)
+        (mcc_type, c_r, value) = RFCOMM_Frame.parse_mcc(frame.information)
 
-        if type == RFCOMM_MCC_PN_TYPE:
+        if mcc_type == RFCOMM_MCC_PN_TYPE:
             pn = RFCOMM_MCC_PN.from_bytes(value)
             self.on_mcc_pn(c_r, pn)
-        elif type == RFCOMM_MCC_MSC_TYPE:
+        elif mcc_type == RFCOMM_MCC_MSC_TYPE:
             mcs = RFCOMM_MCC_MSC.from_bytes(value)
             self.on_mcc_msc(c_r, mcs)
 
@@ -669,7 +706,7 @@ class Multiplexer(EventEmitter):
             if pn.dlci & 1:
                 # Not expected, this is an initiator-side number
                 # TODO: error out
-                logger.warn(f'invalid DLCI: {pn.dlci}')
+                logger.warning(f'invalid DLCI: {pn.dlci}')
             else:
                 if self.acceptor:
                     channel_number = pn.dlci >> 1
@@ -688,7 +725,7 @@ class Multiplexer(EventEmitter):
                         self.send_frame(RFCOMM_Frame.dm(c_r=1, dlci=pn.dlci))
                 else:
                     # No acceptor?? shouldn't happen
-                    logger.warn(color('!!! no acceptor registered', 'red'))
+                    logger.warning(color('!!! no acceptor registered', 'red'))
         else:
             # Response
             logger.debug(f'>>> PN Response: {pn}')
@@ -697,12 +734,12 @@ class Multiplexer(EventEmitter):
                 self.dlcs[pn.dlci] = dlc
                 dlc.connect()
             else:
-                logger.warn('ignoring PN response')
+                logger.warning('ignoring PN response')
 
     def on_mcc_msc(self, c_r, msc):
         dlc = self.dlcs.get(msc.dlci)
         if dlc is None:
-            logger.warn(f'no dlc for DLCI {msc.dlci}')
+            logger.warning(f'no dlc for DLCI {msc.dlci}')
             return
         dlc.on_mcc_msc(c_r, msc)
 
@@ -732,8 +769,8 @@ class Multiplexer(EventEmitter):
         if self.state != Multiplexer.CONNECTED:
             if self.state == Multiplexer.OPENING:
                 raise InvalidStateError('open already in progress')
-            else:
+
-                raise InvalidStateError('not connected')
+            raise InvalidStateError('not connected')
 
         pn = RFCOMM_MCC_PN(
             dlci=channel << 1,
@@ -744,7 +781,7 @@ class Multiplexer(EventEmitter):
             max_retransmissions=0,
             window_size=RFCOMM_DEFAULT_INITIAL_RX_CREDITS,
         )
-        mcc = RFCOMM_Frame.make_mcc(type=RFCOMM_MCC_PN_TYPE, c_r=1, data=bytes(pn))
+        mcc = RFCOMM_Frame.make_mcc(mcc_type=RFCOMM_MCC_PN_TYPE, c_r=1, data=bytes(pn))
         logger.debug(f'>>> Sending MCC: {pn}')
         self.open_result = asyncio.get_running_loop().create_future()
         self.change_state(Multiplexer.OPENING)
@@ -784,7 +821,7 @@ class Client:
                 self.connection, RFCOMM_PSM
             )
         except ProtocolError as error:
-            logger.warn(f'L2CAP connection failed: {error}')
+            logger.warning(f'L2CAP connection failed: {error}')
             raise
 
         # Create a mutliplexer to manage DLCs with the server

bumble/sdp.py

@@ -15,10 +15,12 @@
 # -----------------------------------------------------------------------------
 # Imports
 # -----------------------------------------------------------------------------
+from __future__ import annotations
 import logging
 import struct
 from colors import color
 import colors
+from typing import Dict, List, Type
 
 from . import core
 from .core import InvalidStateError
@@ -34,6 +36,7 @@ logger = logging.getLogger(__name__)
 # Constants
 # -----------------------------------------------------------------------------
 # fmt: off
+# pylint: disable=line-too-long
 
 SDP_CONTINUATION_WATCHDOG = 64  # Maximum number of continuations we're willing to do
 
@@ -115,6 +118,8 @@ SDP_PUBLIC_BROWSE_ROOT = core.UUID.from_16_bits(0x1002, 'PublicBrowseRoot')
 SDP_ALL_ATTRIBUTES_RANGE = (0x0000FFFF, 4)  # Express this as tuple so we can convey the desired encoding size
 
 # fmt: on
+# pylint: enable=line-too-long
+# pylint: disable=invalid-name
 
 
 # -----------------------------------------------------------------------------
@@ -167,100 +172,107 @@ class DataElement:
         URL: lambda x: DataElement(DataElement.URL, x.decode('utf8')),
     }
 
-    def __init__(self, type, value, value_size=None):
+    def __init__(self, element_type, value, value_size=None):
-        self.type = type
+        self.type = element_type
         self.value = value
         self.value_size = value_size
-        self.bytes = None  # Used a cache when parsing from bytes so we can emit a byte-for-byte replica
+        # Used as a cache when parsing from bytes so we can emit a byte-for-byte replica
-        if type == DataElement.UNSIGNED_INTEGER or type == DataElement.SIGNED_INTEGER:
+        self.bytes = None
+        if element_type in (DataElement.UNSIGNED_INTEGER, DataElement.SIGNED_INTEGER):
             if value_size is None:
                 raise ValueError('integer types must have a value size specified')
 
     @staticmethod
-    def nil():
+    def nil() -> DataElement:
         return DataElement(DataElement.NIL, None)
 
     @staticmethod
-    def unsigned_integer(value, value_size):
+    def unsigned_integer(value: int, value_size: int) -> DataElement:
         return DataElement(DataElement.UNSIGNED_INTEGER, value, value_size)
 
     @staticmethod
-    def unsigned_integer_8(value):
+    def unsigned_integer_8(value: int) -> DataElement:
         return DataElement(DataElement.UNSIGNED_INTEGER, value, value_size=1)
 
     @staticmethod
-    def unsigned_integer_16(value):
+    def unsigned_integer_16(value: int) -> DataElement:
         return DataElement(DataElement.UNSIGNED_INTEGER, value, value_size=2)
 
     @staticmethod
-    def unsigned_integer_32(value):
+    def unsigned_integer_32(value: int) -> DataElement:
         return DataElement(DataElement.UNSIGNED_INTEGER, value, value_size=4)
 
     @staticmethod
-    def signed_integer(value, value_size):
+    def signed_integer(value: int, value_size: int) -> DataElement:
         return DataElement(DataElement.SIGNED_INTEGER, value, value_size)
 
     @staticmethod
-    def signed_integer_8(value):
+    def signed_integer_8(value: int) -> DataElement:
         return DataElement(DataElement.SIGNED_INTEGER, value, value_size=1)
 
     @staticmethod
-    def signed_integer_16(value):
+    def signed_integer_16(value: int) -> DataElement:
         return DataElement(DataElement.SIGNED_INTEGER, value, value_size=2)
 
     @staticmethod
-    def signed_integer_32(value):
+    def signed_integer_32(value: int) -> DataElement:
         return DataElement(DataElement.SIGNED_INTEGER, value, value_size=4)
 
     @staticmethod
-    def uuid(value):
+    def uuid(value: core.UUID) -> DataElement:
         return DataElement(DataElement.UUID, value)
 
     @staticmethod
-    def text_string(value):
+    def text_string(value: str) -> DataElement:
         return DataElement(DataElement.TEXT_STRING, value)
 
     @staticmethod
-    def boolean(value):
+    def boolean(value: bool) -> DataElement:
         return DataElement(DataElement.BOOLEAN, value)
 
     @staticmethod
-    def sequence(value):
+    def sequence(value: List[DataElement]) -> DataElement:
         return DataElement(DataElement.SEQUENCE, value)
 
     @staticmethod
-    def alternative(value):
+    def alternative(value: List[DataElement]) -> DataElement:
         return DataElement(DataElement.ALTERNATIVE, value)
 
     @staticmethod
-    def url(value):
+    def url(value: str) -> DataElement:
         return DataElement(DataElement.URL, value)
 
     @staticmethod
     def unsigned_integer_from_bytes(data):
         if len(data) == 1:
             return data[0]
-        elif len(data) == 2:
+
+        if len(data) == 2:
             return struct.unpack('>H', data)[0]
-        elif len(data) == 4:
+
+        if len(data) == 4:
             return struct.unpack('>I', data)[0]
-        elif len(data) == 8:
+
+        if len(data) == 8:
             return struct.unpack('>Q', data)[0]
-        else:
+
-            raise ValueError(f'invalid integer length {len(data)}')
+        raise ValueError(f'invalid integer length {len(data)}')
 
     @staticmethod
     def signed_integer_from_bytes(data):
         if len(data) == 1:
             return struct.unpack('b', data)[0]
-        elif len(data) == 2:
+
+        if len(data) == 2:
             return struct.unpack('>h', data)[0]
-        elif len(data) == 4:
+
+        if len(data) == 4:
             return struct.unpack('>i', data)[0]
-        elif len(data) == 8:
+
+        if len(data) == 8:
             return struct.unpack('>q', data)[0]
-        else:
+
-            raise ValueError(f'invalid integer length {len(data)}')
+        raise ValueError(f'invalid integer length {len(data)}')
 
     @staticmethod
     def list_from_bytes(data):
@@ -278,11 +290,11 @@ class DataElement:
 
     @staticmethod
     def from_bytes(data):
-        type = data[0] >> 3
+        element_type = data[0] >> 3
         size_index = data[0] & 7
         value_offset = 0
         if size_index == 0:
-            if type == DataElement.NIL:
+            if element_type == DataElement.NIL:
                 value_size = 0
             else:
                 value_size = 1
@@ -305,17 +317,17 @@ class DataElement:
             value_offset = 4
 
         value_data = data[1 + value_offset : 1 + value_offset + value_size]
-        constructor = DataElement.type_constructors.get(type)
+        constructor = DataElement.type_constructors.get(element_type)
         if constructor:
-            if (
+            if element_type in (
-                type == DataElement.UNSIGNED_INTEGER
+                DataElement.UNSIGNED_INTEGER,
-                or type == DataElement.SIGNED_INTEGER
+                DataElement.SIGNED_INTEGER,
             ):
                 result = constructor(value_data, value_size)
             else:
                 result = constructor(value_data)
         else:
-            result = DataElement(type, value_data)
+            result = DataElement(element_type, value_data)
         result.bytes = data[
             : 1 + value_offset + value_size
         ]  # Keep a copy so we can re-serialize to an exact replica
@@ -334,7 +346,8 @@ class DataElement:
         elif self.type == DataElement.UNSIGNED_INTEGER:
             if self.value < 0:
                 raise ValueError('UNSIGNED_INTEGER cannot be negative')
-            elif self.value_size == 1:
+
+            if self.value_size == 1:
                 data = struct.pack('B', self.value)
             elif self.value_size == 2:
                 data = struct.pack('>H', self.value)
@@ -357,11 +370,11 @@ class DataElement:
                 raise ValueError('invalid value_size')
         elif self.type == DataElement.UUID:
             data = bytes(reversed(bytes(self.value)))
-        elif self.type == DataElement.TEXT_STRING or self.type == DataElement.URL:
+        elif self.type in (DataElement.TEXT_STRING, DataElement.URL):
             data = self.value.encode('utf8')
         elif self.type == DataElement.BOOLEAN:
             data = bytes([1 if self.value else 0])
-        elif self.type == DataElement.SEQUENCE or self.type == DataElement.ALTERNATIVE:
+        elif self.type in (DataElement.SEQUENCE, DataElement.ALTERNATIVE):
             data = b''.join([bytes(element) for element in self.value])
         else:
             data = self.value
@@ -372,10 +385,10 @@ class DataElement:
             if size != 0:
                 raise ValueError('NIL must be empty')
             size_index = 0
-        elif (
+        elif self.type in (
-            self.type == DataElement.UNSIGNED_INTEGER
+            DataElement.UNSIGNED_INTEGER,
-            or self.type == DataElement.SIGNED_INTEGER
+            DataElement.SIGNED_INTEGER,
-            or self.type == DataElement.UUID
+            DataElement.UUID,
         ):
             if size <= 1:
                 size_index = 0
@@ -389,11 +402,11 @@ class DataElement:
                 size_index = 4
             else:
                 raise ValueError('invalid data size')
-        elif (
+        elif self.type in (
-            self.type == DataElement.TEXT_STRING
+            DataElement.TEXT_STRING,
-            or self.type == DataElement.SEQUENCE
+            DataElement.SEQUENCE,
-            or self.type == DataElement.ALTERNATIVE
+            DataElement.ALTERNATIVE,
-            or self.type == DataElement.URL
+            DataElement.URL,
         ):
             if size <= 0xFF:
                 size_index = 5
@@ -419,14 +432,19 @@ class DataElement:
         type_name = name_or_number(self.TYPE_NAMES, self.type)
         if self.type == DataElement.NIL:
             value_string = ''
-        elif self.type == DataElement.SEQUENCE or self.type == DataElement.ALTERNATIVE:
+        elif self.type in (DataElement.SEQUENCE, DataElement.ALTERNATIVE):
             container_separator = '\n' if pretty else ''
             element_separator = '\n' if pretty else ','
-            value_string = f'[{container_separator}{element_separator.join([element.to_string(pretty, indentation + 1 if pretty else 0) for element in self.value])}{container_separator}{prefix}]'
+            elements = [
-        elif (
+                element.to_string(pretty, indentation + 1 if pretty else 0)
-            self.type == DataElement.UNSIGNED_INTEGER
+                for element in self.value
-            or self.type == DataElement.SIGNED_INTEGER
+            ]
-        ):
+            value_string = (
+                f'[{container_separator}'
+                f'{element_separator.join(elements)}'
+                f'{container_separator}{prefix}]'
+            )
+        elif self.type in (DataElement.UNSIGNED_INTEGER, DataElement.SIGNED_INTEGER):
             value_string = f'{self.value}#{self.value_size}'
         elif isinstance(self.value, DataElement):
             value_string = self.value.to_string(pretty, indentation)
@@ -440,8 +458,8 @@ class DataElement:
 
 # -----------------------------------------------------------------------------
 class ServiceAttribute:
-    def __init__(self, id, value):
+    def __init__(self, attribute_id: int, value: DataElement) -> None:
-        self.id = id
+        self.id = attribute_id
         self.value = value
 
     @staticmethod
@@ -450,7 +468,7 @@ class ServiceAttribute:
         for i in range(0, len(elements) // 2):
             attribute_id, attribute_value = elements[2 * i : 2 * (i + 1)]
             if attribute_id.type != DataElement.UNSIGNED_INTEGER:
-                logger.warn('attribute ID element is not an integer')
+                logger.warning('attribute ID element is not an integer')
                 continue
             attribute_list.append(ServiceAttribute(attribute_id.value, attribute_value))
 
@@ -468,27 +486,31 @@ class ServiceAttribute:
         )
 
     @staticmethod
-    def id_name(id):
+    def id_name(id_code):
-        return name_or_number(SDP_ATTRIBUTE_ID_NAMES, id)
+        return name_or_number(SDP_ATTRIBUTE_ID_NAMES, id_code)
 
     @staticmethod
     def is_uuid_in_value(uuid, value):
         # Find if a uuid matches a value, either directly or recursing into sequences
         if value.type == DataElement.UUID:
             return value.value == uuid
-        elif value.type == DataElement.SEQUENCE:
+
+        if value.type == DataElement.SEQUENCE:
             for element in value.value:
                 if ServiceAttribute.is_uuid_in_value(uuid, element):
                     return True
             return False
-        else:
-            return False
 
-    def to_string(self, color=False):
+        return False
-        if color:
+
-            return f'Attribute(id={colors.color(self.id_name(self.id),"magenta")},value={self.value})'
+    def to_string(self, with_colors=False):
-        else:
+        if with_colors:
-            return f'Attribute(id={self.id_name(self.id)},value={self.value})'
+            return (
+                f'Attribute(id={colors.color(self.id_name(self.id),"magenta")},'
+                f'value={self.value})'
+            )
+
+        return f'Attribute(id={self.id_name(self.id)},value={self.value})'
 
     def __str__(self):
         return self.to_string()
@@ -500,11 +522,13 @@ class SDP_PDU:
     See Bluetooth spec @ Vol 3, Part B - 4.2 PROTOCOL DATA UNIT FORMAT
     '''
 
-    sdp_pdu_classes = {}
+    sdp_pdu_classes: Dict[int, Type[SDP_PDU]] = {}
+    name = None
+    pdu_id = 0
 
     @staticmethod
     def from_bytes(pdu):
-        pdu_id, transaction_id, parameters_length = struct.unpack_from('>BHH', pdu, 0)
+        pdu_id, transaction_id, _parameters_length = struct.unpack_from('>BHH', pdu, 0)
 
         cls = SDP_PDU.sdp_pdu_classes.get(pdu_id)
         if cls is None:
@@ -755,7 +779,7 @@ class Client:
                 DataElement.unsigned_integer(
                     attribute_id[0], value_size=attribute_id[1]
                 )
-                if type(attribute_id) is tuple
+                if isinstance(attribute_id, tuple)
                 else DataElement.unsigned_integer_16(attribute_id)
                 for attribute_id in attribute_ids
             ]
@@ -787,7 +811,7 @@ class Client:
         # Parse the result into attribute lists
         attribute_lists_sequences = DataElement.from_bytes(accumulator)
         if attribute_lists_sequences.type != DataElement.SEQUENCE:
-            logger.warn('unexpected data type')
+            logger.warning('unexpected data type')
             return []
 
         return [
@@ -805,7 +829,7 @@ class Client:
                 DataElement.unsigned_integer(
                     attribute_id[0], value_size=attribute_id[1]
                 )
-                if type(attribute_id) is tuple
+                if isinstance(attribute_id, tuple)
                 else DataElement.unsigned_integer_16(attribute_id)
                 for attribute_id in attribute_ids
             ]
@@ -837,7 +861,7 @@ class Client:
         # Parse the result into a list of attributes
         attribute_list_sequence = DataElement.from_bytes(accumulator)
         if attribute_list_sequence.type != DataElement.SEQUENCE:
-            logger.warn('unexpected data type')
+            logger.warning('unexpected data type')
             return []
 
         return ServiceAttribute.list_from_data_elements(attribute_list_sequence.value)
@@ -850,6 +874,7 @@ class Server:
     def __init__(self, device):
         self.device = device
         self.service_records = {}  # Service records maps, by record handle
+        self.channel = None
         self.current_response = None
 
     def register(self, l2cap_channel_manager):
@@ -884,7 +909,7 @@ class Server:
         try:
             sdp_pdu = SDP_PDU.from_bytes(pdu)
         except Exception as error:
-            logger.warn(color(f'failed to parse SDP Request PDU: {error}', 'red'))
+            logger.warning(color(f'failed to parse SDP Request PDU: {error}', 'red'))
             self.send_response(
                 SDP_ErrorResponse(
                     transaction_id=0, error_code=SDP_INVALID_REQUEST_SYNTAX_ERROR
@@ -945,7 +970,7 @@ class Server:
                 if attribute.id >= id_range_start and attribute.id <= id_range_end
             ]
 
-        # Return the maching attributes, sorted by attribute id
+        # Return the matching attributes, sorted by attribute id
         attributes.sort(key=lambda x: x.id)
         attribute_list = DataElement.sequence([])
         for attribute in attributes:

bumble/smp.py

@@ -22,14 +22,23 @@
 # -----------------------------------------------------------------------------
 # Imports
 # -----------------------------------------------------------------------------
+from __future__ import annotations
 import logging
 import asyncio
 import secrets
+from typing import Dict, Optional, Type
+
 from pyee import EventEmitter
 from colors import color
 
-from .core import *
+from .hci import Address, HCI_LE_Enable_Encryption_Command, HCI_Object, key_with_value
-from .hci import *
+from .core import (
+    BT_BR_EDR_TRANSPORT,
+    BT_CENTRAL_ROLE,
+    BT_LE_TRANSPORT,
+    ProtocolError,
+    name_or_number,
+)
 from .keys import PairingKeys
 from . import crypto
 
@@ -44,6 +53,7 @@ logger = logging.getLogger(__name__)
 # Constants
 # -----------------------------------------------------------------------------
 # fmt: off
+# pylint: disable=line-too-long
 
 SMP_CID = 0x06
 SMP_BR_CID = 0x07
@@ -158,6 +168,8 @@ SMP_CTKD_H7_LEBR_SALT = bytes.fromhex('00000000000000000000000000000000746D7031'
 SMP_CTKD_H7_BRLE_SALT = bytes.fromhex('00000000000000000000000000000000746D7032')
 
 # fmt: on
+# pylint: enable=line-too-long
+# pylint: disable=invalid-name
 
 
 # -----------------------------------------------------------------------------
@@ -175,8 +187,9 @@ class SMP_Command:
     See Bluetooth spec @ Vol 3, Part H - 3 SECURITY MANAGER PROTOCOL
     '''
 
-    smp_classes = {}
+    smp_classes: Dict[int, Type[SMP_Command]] = {}
     code = 0
+    name = ''
 
     @staticmethod
     def from_bytes(pdu):
@@ -206,7 +219,10 @@ class SMP_Command:
         keypress = (value >> 4) & 1
         ct2 = (value >> 5) & 1
 
-        return f'bonding_flags={bonding_flags}, MITM={mitm}, sc={sc}, keypress={keypress}, ct2={ct2}'
+        return (
+            f'bonding_flags={bonding_flags}, '
+            f'MITM={mitm}, sc={sc}, keypress={keypress}, ct2={ct2}'
+        )
 
     @staticmethod
     def io_capability_name(io_capability):
@@ -458,11 +474,11 @@ class AddressResolver:
 
     def resolve(self, address):
         address_bytes = bytes(address)
-        hash = address_bytes[0:3]
+        hash_part = address_bytes[0:3]
         prand = address_bytes[3:6]
         for (irk, resolved_address) in self.resolving_keys:
             local_hash = crypto.ah(irk, prand)
-            if local_hash == hash:
+            if local_hash == hash_part:
                 # Match!
                 if resolved_address.address_type == Address.PUBLIC_DEVICE_ADDRESS:
                     resolved_address_type = Address.PUBLIC_IDENTITY_ADDRESS
@@ -472,6 +488,8 @@ class AddressResolver:
                     address=str(resolved_address), address_type=resolved_address_type
                 )
 
+        return None
+
 
 # -----------------------------------------------------------------------------
 class PairingDelegate:
@@ -486,27 +504,27 @@ class PairingDelegate:
 
     def __init__(
         self,
-        io_capability=NO_OUTPUT_NO_INPUT,
+        io_capability: int = NO_OUTPUT_NO_INPUT,
-        local_initiator_key_distribution=DEFAULT_KEY_DISTRIBUTION,
+        local_initiator_key_distribution: int = DEFAULT_KEY_DISTRIBUTION,
-        local_responder_key_distribution=DEFAULT_KEY_DISTRIBUTION,
+        local_responder_key_distribution: int = DEFAULT_KEY_DISTRIBUTION,
-    ):
+    ) -> None:
         self.io_capability = io_capability
         self.local_initiator_key_distribution = local_initiator_key_distribution
         self.local_responder_key_distribution = local_responder_key_distribution
 
-    async def accept(self):
+    async def accept(self) -> bool:
         return True
 
-    async def confirm(self):
+    async def confirm(self) -> bool:
         return True
 
-    async def compare_numbers(self, number, digits=6):
+    async def compare_numbers(self, _number: int, _digits: int = 6) -> bool:
         return True
 
-    async def get_number(self):
+    async def get_number(self) -> int:
         return 0
 
-    async def display_number(self, number, digits=6):
+    async def display_number(self, _number: int, _digits: int = 6) -> None:
         pass
 
     async def key_distribution_response(
@@ -520,7 +538,13 @@ class PairingDelegate:
 
 # -----------------------------------------------------------------------------
 class PairingConfig:
-    def __init__(self, sc=True, mitm=True, bonding=True, delegate=None):
+    def __init__(
+        self,
+        sc: bool = True,
+        mitm: bool = True,
+        bonding: bool = True,
+        delegate: Optional[PairingDelegate] = None,
+    ) -> None:
         self.sc = sc
         self.mitm = mitm
         self.bonding = bonding
@@ -528,7 +552,11 @@ class PairingConfig:
 
     def __str__(self):
         io_capability_str = SMP_Command.io_capability_name(self.delegate.io_capability)
-        return f'PairingConfig(sc={self.sc}, mitm={self.mitm}, bonding={self.bonding}, delegate[{io_capability_str}])'
+        return (
+            f'PairingConfig(sc={self.sc}, '
+            f'mitm={self.mitm}, bonding={self.bonding}, '
+            f'delegate[{io_capability_str}])'
+        )
 
 
 # -----------------------------------------------------------------------------
@@ -548,14 +576,16 @@ class Session:
 
     # I/O Capability to pairing method decision matrix
     #
-    # See Bluetooth spec @ Vol 3, part H - Table 2.8: Mapping of IO Capabilities to Key Generation Method
+    # See Bluetooth spec @ Vol 3, part H - Table 2.8: Mapping of IO Capabilities to Key
+    # Generation Method
     #
     # Map: initiator -> responder -> <method>
-    # where <method> may be a simple entry or a 2-element tuple, with the first element for legacy
+    # where <method> may be a simple entry or a 2-element tuple, with the first element
-    # pairing and the second  for secure connections, when the two are different.
+    # for legacy pairing and the second  for secure connections, when the two are
-    # Each entry is either a method name, or, for PASSKEY, a tuple:
+    # different. Each entry is either a method name, or, for PASSKEY, a tuple:
     # (method, initiator_displays, responder_displays)
-    # to specify if the initiator and responder should display (True) or input a code (False).
+    # to specify if the initiator and responder should display (True) or input a code
+    # (False).
     PAIRING_METHODS = {
         SMP_DISPLAY_ONLY_IO_CAPABILITY: {
             SMP_DISPLAY_ONLY_IO_CAPABILITY: JUST_WORKS,
@@ -606,6 +636,10 @@ class Session:
     def __init__(self, manager, connection, pairing_config):
         self.manager = manager
         self.connection = connection
+        self.preq = None
+        self.pres = None
+        self.ea = None
+        self.eb = None
         self.tk = bytes(16)
         self.r = bytes(16)
         self.stk = None
@@ -626,6 +660,7 @@ class Session:
         self.peer_signature_key = None
         self.peer_expected_distributions = []
         self.dh_key = None
+        self.confirm_value = None
         self.passkey = 0
         self.passkey_step = 0
         self.passkey_display = False
@@ -726,6 +761,8 @@ class Session:
         else:
             return self.ltk
 
+        return None
+
     def decide_pairing_method(
         self, auth_req, initiator_io_capability, responder_io_capability
     ):
@@ -734,10 +771,10 @@ class Session:
             return
 
         details = self.PAIRING_METHODS[initiator_io_capability][responder_io_capability]
-        if type(details) is tuple and len(details) == 2:
+        if isinstance(details, tuple) and len(details) == 2:
             # One entry for legacy pairing and one for secure connections
             details = details[1 if self.sc else 0]
-        if type(details) is int:
+        if isinstance(details, int):
             # Just a method ID
             self.pairing_method = details
         else:
@@ -762,11 +799,11 @@ class Session:
                     next_steps()
                     return
             except Exception as error:
-                logger.warn(f'exception while confirm: {error}')
+                logger.warning(f'exception while confirm: {error}')
 
             self.send_pairing_failed(SMP_CONFIRM_VALUE_FAILED_ERROR)
 
-        asyncio.create_task(prompt())
+        self.connection.abort_on('disconnection', prompt())
 
     def prompt_user_for_numeric_comparison(self, code, next_steps):
         async def prompt():
@@ -779,11 +816,11 @@ class Session:
                     next_steps()
                     return
             except Exception as error:
-                logger.warn(f'exception while prompting: {error}')
+                logger.warning(f'exception while prompting: {error}')
 
             self.send_pairing_failed(SMP_CONFIRM_VALUE_FAILED_ERROR)
 
-        asyncio.create_task(prompt())
+        self.connection.abort_on('disconnection', prompt())
 
     def prompt_user_for_number(self, next_steps):
         async def prompt():
@@ -793,10 +830,10 @@ class Session:
                 logger.debug(f'user input: {passkey}')
                 next_steps(passkey)
             except Exception as error:
-                logger.warn(f'exception while prompting: {error}')
+                logger.warning(f'exception while prompting: {error}')
                 self.send_pairing_failed(SMP_PASSKEY_ENTRY_FAILED_ERROR)
 
-        asyncio.create_task(prompt())
+        self.connection.abort_on('disconnection', prompt())
 
     def display_passkey(self):
         # Generate random Passkey/PIN code
@@ -808,8 +845,9 @@ class Session:
             self.tk = self.passkey.to_bytes(16, byteorder='little')
             logger.debug(f'TK from passkey = {self.tk.hex()}')
 
-        asyncio.create_task(
+        self.connection.abort_on(
-            self.pairing_config.delegate.display_number(self.passkey, digits=6)
+            'disconnection',
+            self.pairing_config.delegate.display_number(self.passkey, digits=6),
         )
 
     def input_passkey(self, next_steps=None):
@@ -872,10 +910,7 @@ class Session:
         logger.debug(f'generated random: {self.r.hex()}')
 
         if self.sc:
-            if (
+            if self.pairing_method in (self.JUST_WORKS, self.NUMERIC_COMPARISON):
-                self.pairing_method == self.JUST_WORKS
-                or self.pairing_method == self.NUMERIC_COMPARISON
-            ):
                 z = 0
             elif self.pairing_method == self.PASSKEY:
                 z = 0x80 + ((self.passkey >> self.passkey_step) & 1)
@@ -921,14 +956,12 @@ class Session:
     def start_encryption(self, key):
         # We can now encrypt the connection with the short term key, so that we can
         # distribute the long term and/or other keys over an encrypted connection
-        asyncio.create_task(
+        self.manager.device.host.send_command_sync(
-            self.manager.device.host.send_command(
+            HCI_LE_Enable_Encryption_Command(
-                HCI_LE_Enable_Encryption_Command(
+                connection_handle=self.connection.handle,
-                    connection_handle=self.connection.handle,
+                random_number=bytes(8),
-                    random_number=bytes(8),
+                encrypted_diversifier=0,
-                    encrypted_diversifier=0,
+                long_term_key=key,
-                    long_term_key=key,
-                )
             )
         )
 
@@ -950,7 +983,9 @@ class Session:
                 self.connection.transport == BT_BR_EDR_TRANSPORT
                 and self.initiator_key_distribution & SMP_ENC_KEY_DISTRIBUTION_FLAG
             ):
-                self.ctkd_task = asyncio.create_task(self.derive_ltk())
+                self.ctkd_task = self.connection.abort_on(
+                    'disconnection', self.derive_ltk()
+                )
             elif not self.sc:
                 # Distribute the LTK, EDIV and RAND
                 if self.initiator_key_distribution & SMP_ENC_KEY_DISTRIBUTION_FLAG:
@@ -997,7 +1032,9 @@ class Session:
                 self.connection.transport == BT_BR_EDR_TRANSPORT
                 and self.responder_key_distribution & SMP_ENC_KEY_DISTRIBUTION_FLAG
             ):
-                self.ctkd_task = asyncio.create_task(self.derive_ltk())
+                self.ctkd_task = self.connection.abort_on(
+                    'disconnection', self.derive_ltk()
+                )
             # Distribute the LTK, EDIV and RAND
             elif not self.sc:
                 if self.responder_key_distribution & SMP_ENC_KEY_DISTRIBUTION_FLAG:
@@ -1057,13 +1094,14 @@ class Session:
         if key_distribution_flags & SMP_SIGN_KEY_DISTRIBUTION_FLAG != 0:
             self.peer_expected_distributions.append(SMP_Signing_Information_Command)
         logger.debug(
-            f'expecting distributions: {[c.__name__ for c in self.peer_expected_distributions]}'
+            'expecting distributions: '
+            f'{[c.__name__ for c in self.peer_expected_distributions]}'
         )
 
     def check_key_distribution(self, command_class):
         # First, check that the connection is encrypted
         if not self.connection.is_encrypted:
-            logger.warn(
+            logger.warning(
                 color('received key distribution on a non-encrypted connection', 'red')
             )
             self.send_pairing_failed(SMP_UNSPECIFIED_REASON_ERROR)
@@ -1073,14 +1111,16 @@ class Session:
         if command_class in self.peer_expected_distributions:
             self.peer_expected_distributions.remove(command_class)
             logger.debug(
-                f'remaining distributions: {[c.__name__ for c in self.peer_expected_distributions]}'
+                'remaining distributions: '
+                f'{[c.__name__ for c in self.peer_expected_distributions]}'
             )
             if not self.peer_expected_distributions:
                 self.on_peer_key_distribution_complete()
         else:
-            logger.warn(
+            logger.warning(
                 color(
-                    f'!!! unexpected key distribution command: {command_class.__name__}',
+                    '!!! unexpected key distribution command: '
+                    f'{command_class.__name__}',
                     'red',
                 )
             )
@@ -1094,9 +1134,9 @@ class Session:
         self.send_pairing_request_command()
 
         # Wait for the pairing process to finish
-        await self.pairing_result
+        await self.connection.abort_on('disconnection', self.pairing_result)
 
-    def on_disconnection(self, reason):
+    def on_disconnection(self, _):
         self.connection.remove_listener('disconnection', self.on_disconnection)
         self.connection.remove_listener(
             'connection_encryption_change', self.on_connection_encryption_change
@@ -1112,7 +1152,7 @@ class Session:
         if self.is_initiator:
             self.distribute_keys()
 
-        asyncio.create_task(self.on_pairing())
+        self.connection.abort_on('disconnection', self.on_pairing())
 
     def on_connection_encryption_change(self):
         if self.connection.is_encrypted:
@@ -1133,8 +1173,8 @@ class Session:
 
         if self.completed:
             return
-        else:
+
-            self.completed = True
+        self.completed = True
 
         if self.pairing_result is not None and not self.pairing_result.done():
             self.pairing_result.set_result(None)
@@ -1194,8 +1234,8 @@ class Session:
 
         if self.completed:
             return
-        else:
+
-            self.completed = True
+        self.completed = True
 
         error = ProtocolError(reason, 'smp', error_name(reason))
         if self.pairing_result is not None and not self.pairing_result.done():
@@ -1219,7 +1259,9 @@ class Session:
             logger.error(color('SMP command not handled???', 'red'))
 
     def on_smp_pairing_request_command(self, command):
-        asyncio.create_task(self.on_smp_pairing_request_command_async(command))
+        self.connection.abort_on(
+            'disconnection', self.on_smp_pairing_request_command_async(command)
+        )
 
     async def on_smp_pairing_request_command_async(self, command):
         # Check if the request should proceed
@@ -1239,7 +1281,7 @@ class Session:
 
         # Check for OOB
         if command.oob_data_flag != 0:
-            self.terminate(SMP_OOB_NOT_AVAILABLE_ERROR)
+            self.send_pairing_failed(SMP_OOB_NOT_AVAILABLE_ERROR)
             return
 
         # Decide which pairing method to use
@@ -1283,7 +1325,7 @@ class Session:
 
     def on_smp_pairing_response_command(self, command):
         if self.is_responder:
-            logger.warn(color('received pairing response as a responder', 'red'))
+            logger.warning(color('received pairing response as a responder', 'red'))
             return
 
         # Save the response
@@ -1332,7 +1374,7 @@ class Session:
             else:
                 self.send_pairing_confirm_command()
 
-    def on_smp_pairing_confirm_command_legacy(self, command):
+    def on_smp_pairing_confirm_command_legacy(self, _):
         if self.is_initiator:
             self.send_pairing_random_command()
         else:
@@ -1342,11 +1384,8 @@ class Session:
             else:
                 self.send_pairing_confirm_command()
 
-    def on_smp_pairing_confirm_command_secure_connections(self, command):
+    def on_smp_pairing_confirm_command_secure_connections(self, _):
-        if (
+        if self.pairing_method in (self.JUST_WORKS, self.NUMERIC_COMPARISON):
-            self.pairing_method == self.JUST_WORKS
-            or self.pairing_method == self.NUMERIC_COMPARISON
-        ):
             if self.is_initiator:
                 self.r = crypto.r()
                 self.send_pairing_random_command()
@@ -1399,11 +1438,9 @@ class Session:
             self.send_pairing_random_command()
 
     def on_smp_pairing_random_command_secure_connections(self, command):
+        # pylint: disable=too-many-return-statements
         if self.is_initiator:
-            if (
+            if self.pairing_method in (self.JUST_WORKS, self.NUMERIC_COMPARISON):
-                self.pairing_method == self.JUST_WORKS
-                or self.pairing_method == self.NUMERIC_COMPARISON
-            ):
                 # Check that the random value matches what was committed to earlier
                 confirm_verifier = crypto.f4(
                     self.pkb, self.pka, command.random_value, bytes([0])
@@ -1434,10 +1471,7 @@ class Session:
             else:
                 return
         else:
-            if (
+            if self.pairing_method in (self.JUST_WORKS, self.NUMERIC_COMPARISON):
-                self.pairing_method == self.JUST_WORKS
-                or self.pairing_method == self.NUMERIC_COMPARISON
-            ):
                 self.send_pairing_random_command()
             elif self.pairing_method == self.PASSKEY:
                 # Check that the random value matches what was committed to earlier
@@ -1469,10 +1503,7 @@ class Session:
         (mac_key, self.ltk) = crypto.f5(self.dh_key, self.na, self.nb, a, b)
 
         # Compute the DH Key checks
-        if (
+        if self.pairing_method in (self.JUST_WORKS, self.NUMERIC_COMPARISON):
-            self.pairing_method == self.JUST_WORKS
-            or self.pairing_method == self.NUMERIC_COMPARISON
-        ):
             ra = bytes(16)
             rb = ra
         elif self.pairing_method == self.PASSKEY:
@@ -1497,10 +1528,7 @@ class Session:
                     self.wait_before_continuing.set_result(None)
 
         # Prompt the user for confirmation if needed
-        if (
+        if self.pairing_method in (self.JUST_WORKS, self.NUMERIC_COMPARISON):
-            self.pairing_method == self.JUST_WORKS
-            or self.pairing_method == self.NUMERIC_COMPARISON
-        ):
             # Compute the 6-digit code
             code = crypto.g2(self.pka, self.pkb, self.na, self.nb) % 1000000
 
@@ -1549,10 +1577,7 @@ class Session:
             else:
                 self.send_public_key_command()
 
-            if (
+            if self.pairing_method in (self.JUST_WORKS, self.NUMERIC_COMPARISON):
-                self.pairing_method == self.JUST_WORKS
-                or self.pairing_method == self.NUMERIC_COMPARISON
-            ):
                 # We can now send the confirmation value
                 self.send_pairing_confirm_command()
 
@@ -1572,7 +1597,7 @@ class Session:
                     self.wait_before_continuing = None
                     self.send_pairing_dhkey_check_command()
 
-                asyncio.create_task(next_steps())
+                self.connection.abort_on('disconnection', next_steps())
             else:
                 self.send_pairing_dhkey_check_command()
         else:
@@ -1618,7 +1643,8 @@ class Manager(EventEmitter):
 
     def send_command(self, connection, command):
         logger.debug(
-            f'>>> Sending SMP Command on connection [0x{connection.handle:04X}] {connection.peer_address}: {command}'
+            f'>>> Sending SMP Command on connection [0x{connection.handle:04X}] '
+            f'{connection.peer_address}: {command}'
         )
         cid = SMP_BR_CID if connection.transport == BT_BR_EDR_TRANSPORT else SMP_CID
         connection.send_l2cap_pdu(cid, command.to_bytes())
@@ -1640,7 +1666,8 @@ class Manager(EventEmitter):
         # Parse the L2CAP payload into an SMP Command object
         command = SMP_Command.from_bytes(pdu)
         logger.debug(
-            f'<<< Received SMP Command on connection [0x{connection.handle:04X}] {connection.peer_address}: {command}'
+            f'<<< Received SMP Command on connection [0x{connection.handle:04X}] '
+            f'{connection.peer_address}: {command}'
         )
 
         # Delegate the handling of the command to the session
@@ -1686,9 +1713,9 @@ class Manager(EventEmitter):
                 try:
                     await self.device.keystore.update(str(identity_address), keys)
                 except Exception as error:
-                    logger.warn(f'!!! error while storing keys: {error}')
+                    logger.warning(f'!!! error while storing keys: {error}')
 
-            asyncio.create_task(store_keys())
+            self.device.abort_on('flush', store_keys())
 
         # Notify the device
         self.device.on_pairing(session.connection.handle, keys, session.sc)
@@ -1704,3 +1731,5 @@ class Manager(EventEmitter):
     def get_long_term_key(self, connection, rand, ediv):
         if session := self.sessions.get(connection.handle):
             return session.get_long_term_key(rand, ediv)
+
+        return None

bumble/transport/__init__.py

@@ -28,68 +28,83 @@ logger = logging.getLogger(__name__)
 
 
 # -----------------------------------------------------------------------------
-async def open_transport(name):
+async def open_transport(name: str) -> Transport:
     '''
     Open a transport by name.
     The name must be <type>:<parameters>
     Where <parameters> depend on the type (and may be empty for some types).
     The supported types are: serial,udp,tcp,pty,usb
     '''
+    # pylint: disable=import-outside-toplevel
+    # pylint: disable=too-many-return-statements
+
     scheme, *spec = name.split(':', 1)
     if scheme == 'serial' and spec:
         from .serial import open_serial_transport
 
         return await open_serial_transport(spec[0])
-    elif scheme == 'udp' and spec:
+
+    if scheme == 'udp' and spec:
         from .udp import open_udp_transport
 
         return await open_udp_transport(spec[0])
-    elif scheme == 'tcp-client' and spec:
+
+    if scheme == 'tcp-client' and spec:
         from .tcp_client import open_tcp_client_transport
 
         return await open_tcp_client_transport(spec[0])
-    elif scheme == 'tcp-server' and spec:
+
+    if scheme == 'tcp-server' and spec:
         from .tcp_server import open_tcp_server_transport
 
         return await open_tcp_server_transport(spec[0])
-    elif scheme == 'ws-client' and spec:
+
+    if scheme == 'ws-client' and spec:
         from .ws_client import open_ws_client_transport
 
         return await open_ws_client_transport(spec[0])
-    elif scheme == 'ws-server' and spec:
+
+    if scheme == 'ws-server' and spec:
         from .ws_server import open_ws_server_transport
 
         return await open_ws_server_transport(spec[0])
-    elif scheme == 'pty':
+
+    if scheme == 'pty':
         from .pty import open_pty_transport
 
         return await open_pty_transport(spec[0] if spec else None)
-    elif scheme == 'file':
+
+    if scheme == 'file':
         from .file import open_file_transport
 
         return await open_file_transport(spec[0] if spec else None)
-    elif scheme == 'vhci':
+
+    if scheme == 'vhci':
         from .vhci import open_vhci_transport
 
         return await open_vhci_transport(spec[0] if spec else None)
-    elif scheme == 'hci-socket':
+
+    if scheme == 'hci-socket':
         from .hci_socket import open_hci_socket_transport
 
         return await open_hci_socket_transport(spec[0] if spec else None)
-    elif scheme == 'usb':
+
+    if scheme == 'usb':
         from .usb import open_usb_transport
 
         return await open_usb_transport(spec[0] if spec else None)
-    elif scheme == 'pyusb':
+
+    if scheme == 'pyusb':
         from .pyusb import open_pyusb_transport
 
         return await open_pyusb_transport(spec[0] if spec else None)
-    elif scheme == 'android-emulator':
+
+    if scheme == 'android-emulator':
         from .android_emulator import open_android_emulator_transport
 
         return await open_android_emulator_transport(spec[0] if spec else None)
-    else:
+
-        raise ValueError('unknown transport scheme')
+    raise ValueError('unknown transport scheme')
 
 
 # -----------------------------------------------------------------------------
@@ -104,5 +119,5 @@ async def open_transport_or_link(name):
                 link.close()
 
         return LinkTransport(controller, AsyncPipeSink(controller))
-    else:
+
-        return await open_transport(name)
+    return await open_transport(name)

bumble/transport/android_emulator.py

@@ -1,4 +1,4 @@
-# Copyright 2021-2022 Google LLC
+# Copyright 2021-2023 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -20,9 +20,11 @@ import grpc
 
 from .common import PumpedTransport, PumpedPacketSource, PumpedPacketSink
 from .emulated_bluetooth_pb2_grpc import EmulatedBluetoothServiceStub
-from .emulated_bluetooth_packets_pb2 import HCIPacket
 from .emulated_bluetooth_vhci_pb2_grpc import VhciForwardingServiceStub
 
+# pylint: disable-next=no-name-in-module
+from .emulated_bluetooth_packets_pb2 import HCIPacket
+
 
 # -----------------------------------------------------------------------------
 # Logging

bumble/transport/common.py

@@ -65,9 +65,12 @@ class PacketPump:
 # -----------------------------------------------------------------------------
 class PacketParser:
     '''
-    In-line parser that accepts data and emits 'on_packet' when a full packet has been parsed
+    In-line parser that accepts data and emits 'on_packet' when a full packet has been
+    parsed
     '''
 
+    # pylint: disable=attribute-defined-outside-init
+
     NEED_TYPE = 0
     NEED_LENGTH = 1
     NEED_BODY = 2
@@ -256,7 +259,7 @@ class Transport:
     def __iter__(self):
         return iter((self.source, self.sink))
 
-    async def close(self):
+    async def close(self) -> None:
         self.source.close()
         self.sink.close()
 
@@ -278,7 +281,7 @@ class PumpedPacketSource(ParserSource):
                     logger.debug('source pump task done')
                     break
                 except Exception as error:
-                    logger.warn(f'exception while waiting for packet: {error}')
+                    logger.warning(f'exception while waiting for packet: {error}')
                     self.terminated.set_result(error)
                     break
 
@@ -309,7 +312,7 @@ class PumpedPacketSink:
                     logger.debug('sink pump task done')
                     break
                 except Exception as error:
-                    logger.warn(f'exception while sending packet: {error}')
+                    logger.warning(f'exception while sending packet: {error}')
                     break
 
         self.pump_task = asyncio.create_task(pump_packets())

bumble/transport/emulated_bluetooth_packets_pb2.py

@@ -1,4 +1,4 @@
-# Copyright 2021-2022 Google LLC
+# Copyright 2021-2023 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -16,10 +16,9 @@
 # Generated by the protocol buffer compiler.  DO NOT EDIT!
 # source: emulated_bluetooth_packets.proto
 """Generated protocol buffer code."""
+from google.protobuf.internal import builder as _builder
 from google.protobuf import descriptor as _descriptor
 from google.protobuf import descriptor_pool as _descriptor_pool
-from google.protobuf import message as _message
-from google.protobuf import reflection as _reflection
 from google.protobuf import symbol_database as _symbol_database
 
 # @@protoc_insertion_point(imports)
@@ -31,20 +30,10 @@ DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(
     b'\n emulated_bluetooth_packets.proto\x12\x1b\x61ndroid.emulation.bluetooth\"\xfb\x01\n\tHCIPacket\x12?\n\x04type\x18\x01 \x01(\x0e\x32\x31.android.emulation.bluetooth.HCIPacket.PacketType\x12\x0e\n\x06packet\x18\x02 \x01(\x0c\"\x9c\x01\n\nPacketType\x12\x1b\n\x17PACKET_TYPE_UNSPECIFIED\x10\x00\x12\x1b\n\x17PACKET_TYPE_HCI_COMMAND\x10\x01\x12\x13\n\x0fPACKET_TYPE_ACL\x10\x02\x12\x13\n\x0fPACKET_TYPE_SCO\x10\x03\x12\x15\n\x11PACKET_TYPE_EVENT\x10\x04\x12\x13\n\x0fPACKET_TYPE_ISO\x10\x05\x42J\n\x1f\x63om.android.emulation.bluetoothP\x01\xf8\x01\x01\xa2\x02\x03\x41\x45\x42\xaa\x02\x1b\x41ndroid.Emulation.Bluetoothb\x06proto3'
 )
 
-
+_builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, globals())
-_HCIPACKET = DESCRIPTOR.message_types_by_name['HCIPacket']
+_builder.BuildTopDescriptorsAndMessages(
-_HCIPACKET_PACKETTYPE = _HCIPACKET.enum_types_by_name['PacketType']
+    DESCRIPTOR, 'emulated_bluetooth_packets_pb2', globals()
-HCIPacket = _reflection.GeneratedProtocolMessageType(
-    'HCIPacket',
-    (_message.Message,),
-    {
-        'DESCRIPTOR': _HCIPACKET,
-        '__module__': 'emulated_bluetooth_packets_pb2'
-        # @@protoc_insertion_point(class_scope:android.emulation.bluetooth.HCIPacket)
-    },
 )
-_sym_db.RegisterMessage(HCIPacket)
-
 if _descriptor._USE_C_DESCRIPTORS == False:
 
     DESCRIPTOR._options = None

bumble/transport/emulated_bluetooth_packets_pb2.pyi

@@ -0,0 +1,41 @@
+# Copyright 2021-2023 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from google.protobuf.internal import enum_type_wrapper as _enum_type_wrapper
+from google.protobuf import descriptor as _descriptor
+from google.protobuf import message as _message
+from typing import ClassVar as _ClassVar, Optional as _Optional, Union as _Union
+
+DESCRIPTOR: _descriptor.FileDescriptor
+
+class HCIPacket(_message.Message):
+    __slots__ = ["packet", "type"]
+
+    class PacketType(int, metaclass=_enum_type_wrapper.EnumTypeWrapper):
+        __slots__ = []
+    PACKET_FIELD_NUMBER: _ClassVar[int]
+    PACKET_TYPE_ACL: HCIPacket.PacketType
+    PACKET_TYPE_EVENT: HCIPacket.PacketType
+    PACKET_TYPE_HCI_COMMAND: HCIPacket.PacketType
+    PACKET_TYPE_ISO: HCIPacket.PacketType
+    PACKET_TYPE_SCO: HCIPacket.PacketType
+    PACKET_TYPE_UNSPECIFIED: HCIPacket.PacketType
+    TYPE_FIELD_NUMBER: _ClassVar[int]
+    packet: bytes
+    type: HCIPacket.PacketType
+    def __init__(
+        self,
+        type: _Optional[_Union[HCIPacket.PacketType, str]] = ...,
+        packet: _Optional[bytes] = ...,
+    ) -> None: ...

bumble/transport/emulated_bluetooth_packets_pb2_grpc.py

@@ -0,0 +1,17 @@
+# Copyright 2021-2023 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Generated by the gRPC Python protocol compiler plugin. DO NOT EDIT!
+"""Client and server classes corresponding to protobuf-defined services."""
+import grpc

bumble/transport/emulated_bluetooth_pb2.py

@@ -1,4 +1,4 @@
-# Copyright 2021-2022 Google LLC
+# Copyright 2021-2023 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -16,10 +16,9 @@
 # Generated by the protocol buffer compiler.  DO NOT EDIT!
 # source: emulated_bluetooth.proto
 """Generated protocol buffer code."""
+from google.protobuf.internal import builder as _builder
 from google.protobuf import descriptor as _descriptor
 from google.protobuf import descriptor_pool as _descriptor_pool
-from google.protobuf import message as _message
-from google.protobuf import reflection as _reflection
 from google.protobuf import symbol_database as _symbol_database
 
 # @@protoc_insertion_point(imports)
@@ -34,20 +33,8 @@ DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(
     b'\n\x18\x65mulated_bluetooth.proto\x12\x1b\x61ndroid.emulation.bluetooth\x1a emulated_bluetooth_packets.proto\"\x19\n\x07RawData\x12\x0e\n\x06packet\x18\x01 \x01(\x0c\x32\xcb\x02\n\x18\x45mulatedBluetoothService\x12\x64\n\x12registerClassicPhy\x12$.android.emulation.bluetooth.RawData\x1a$.android.emulation.bluetooth.RawData(\x01\x30\x01\x12`\n\x0eregisterBlePhy\x12$.android.emulation.bluetooth.RawData\x1a$.android.emulation.bluetooth.RawData(\x01\x30\x01\x12g\n\x11registerHCIDevice\x12&.android.emulation.bluetooth.HCIPacket\x1a&.android.emulation.bluetooth.HCIPacket(\x01\x30\x01\x42\"\n\x1e\x63om.android.emulator.bluetoothP\x01\x62\x06proto3'
 )
 
-
+_builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, globals())
-_RAWDATA = DESCRIPTOR.message_types_by_name['RawData']
+_builder.BuildTopDescriptorsAndMessages(DESCRIPTOR, 'emulated_bluetooth_pb2', globals())
-RawData = _reflection.GeneratedProtocolMessageType(
-    'RawData',
-    (_message.Message,),
-    {
-        'DESCRIPTOR': _RAWDATA,
-        '__module__': 'emulated_bluetooth_pb2'
-        # @@protoc_insertion_point(class_scope:android.emulation.bluetooth.RawData)
-    },
-)
-_sym_db.RegisterMessage(RawData)
-
-_EMULATEDBLUETOOTHSERVICE = DESCRIPTOR.services_by_name['EmulatedBluetoothService']
 if _descriptor._USE_C_DESCRIPTORS == False:
 
     DESCRIPTOR._options = None

bumble/transport/emulated_bluetooth_pb2.pyi

@@ -0,0 +1,26 @@
+# Copyright 2021-2023 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import emulated_bluetooth_packets_pb2 as _emulated_bluetooth_packets_pb2
+from google.protobuf import descriptor as _descriptor
+from google.protobuf import message as _message
+from typing import ClassVar as _ClassVar, Optional as _Optional
+
+DESCRIPTOR: _descriptor.FileDescriptor
+
+class RawData(_message.Message):
+    __slots__ = ["packet"]
+    PACKET_FIELD_NUMBER: _ClassVar[int]
+    packet: bytes
+    def __init__(self, packet: _Optional[bytes] = ...) -> None: ...

bumble/transport/emulated_bluetooth_pb2_grpc.py

@@ -1,4 +1,4 @@
-# Copyright 2021-2022 Google LLC
+# Copyright 2021-2023 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.

bumble/transport/emulated_bluetooth_vhci_pb2.py

@@ -1,4 +1,4 @@
-# Copyright 2021-2022 Google LLC
+# Copyright 2021-2023 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -16,10 +16,9 @@
 # Generated by the protocol buffer compiler.  DO NOT EDIT!
 # source: emulated_bluetooth_vhci.proto
 """Generated protocol buffer code."""
+from google.protobuf.internal import builder as _builder
 from google.protobuf import descriptor as _descriptor
 from google.protobuf import descriptor_pool as _descriptor_pool
-from google.protobuf import message as _message
-from google.protobuf import reflection as _reflection
 from google.protobuf import symbol_database as _symbol_database
 
 # @@protoc_insertion_point(imports)
@@ -27,15 +26,17 @@ from google.protobuf import symbol_database as _symbol_database
 _sym_db = _symbol_database.Default()
 
 
-import emulated_bluetooth_packets_pb2 as emulated__bluetooth__packets__pb2
+from . import emulated_bluetooth_packets_pb2 as emulated__bluetooth__packets__pb2
 
 
 DESCRIPTOR = _descriptor_pool.Default().AddSerializedFile(
     b'\n\x1d\x65mulated_bluetooth_vhci.proto\x12\x1b\x61ndroid.emulation.bluetooth\x1a emulated_bluetooth_packets.proto2y\n\x15VhciForwardingService\x12`\n\nattachVhci\x12&.android.emulation.bluetooth.HCIPacket\x1a&.android.emulation.bluetooth.HCIPacket(\x01\x30\x01\x42J\n\x1f\x63om.android.emulation.bluetoothP\x01\xf8\x01\x01\xa2\x02\x03\x41\x45\x42\xaa\x02\x1b\x41ndroid.Emulation.Bluetoothb\x06proto3'
 )
 
-
+_builder.BuildMessageAndEnumDescriptors(DESCRIPTOR, globals())
-_VHCIFORWARDINGSERVICE = DESCRIPTOR.services_by_name['VhciForwardingService']
+_builder.BuildTopDescriptorsAndMessages(
+    DESCRIPTOR, 'emulated_bluetooth_vhci_pb2', globals()
+)
 if _descriptor._USE_C_DESCRIPTORS == False:
 
     DESCRIPTOR._options = None

bumble/transport/emulated_bluetooth_vhci_pb2.pyi

@@ -0,0 +1,19 @@
+# Copyright 2021-2023 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import emulated_bluetooth_packets_pb2 as _emulated_bluetooth_packets_pb2
+from google.protobuf import descriptor as _descriptor
+from typing import ClassVar as _ClassVar
+
+DESCRIPTOR: _descriptor.FileDescriptor

bumble/transport/emulated_bluetooth_vhci_pb2_grpc.py

@@ -1,4 +1,4 @@
-# Copyright 2021-2022 Google LLC
+# Copyright 2021-2023 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.

bumble/transport/file.py

@@ -30,8 +30,9 @@ logger = logging.getLogger(__name__)
 # -----------------------------------------------------------------------------
 async def open_file_transport(spec):
     '''
-    Open a File transport (typically not for a real file, but for a PTY or other unix virtual files).
+    Open a File transport (typically not for a real file, but for a PTY or other unix
-    The parameter string is the path of the file to open
+    virtual files).
+    The parameter string is the path of the file to open.
     '''
 
     # Open the file
@@ -39,12 +40,12 @@ async def open_file_transport(spec):
 
     # Setup reading
     read_transport, packet_source = await asyncio.get_running_loop().connect_read_pipe(
-        lambda: StreamPacketSource(), file
+        StreamPacketSource, file
     )
 
     # Setup writing
     write_transport, _ = await asyncio.get_running_loop().connect_write_pipe(
-        lambda: asyncio.BaseProtocol(), file
+        asyncio.BaseProtocol, file
     )
     packet_sink = StreamPacketSink(write_transport)
 

bumble/transport/hci_socket.py

@@ -40,7 +40,7 @@ async def open_hci_socket_transport(spec):
     or a 0-based integer to indicate the adapter number.
     '''
 
-    HCI_CHANNEL_USER = 1
+    HCI_CHANNEL_USER = 1  # pylint: disable=invalid-name
 
     # Create a raw HCI socket
     try:
@@ -49,10 +49,12 @@ async def open_hci_socket_transport(spec):
             socket.SOCK_RAW | socket.SOCK_NONBLOCK,
             socket.BTPROTO_HCI,
         )
-    except AttributeError:
+    except AttributeError as error:
         # Not supported on this platform
         logger.info("HCI sockets not supported on this platform")
-        raise Exception('Bluetooth HCI sockets not supported on this platform')
+        raise Exception(
+            'Bluetooth HCI sockets not supported on this platform'
+        ) from error
 
     # Compute the adapter index
     if spec is None:
@@ -66,13 +68,19 @@ async def open_hci_socket_transport(spec):
     try:
         ctypes.cdll.LoadLibrary('libc.so.6')
         libc = ctypes.CDLL('libc.so.6', use_errno=True)
-    except OSError:
+    except OSError as error:
         logger.info("HCI sockets not supported on this platform")
-        raise Exception('Bluetooth HCI sockets not supported on this platform')
+        raise Exception(
+            'Bluetooth HCI sockets not supported on this platform'
+        ) from error
     libc.bind.argtypes = (ctypes.c_int, ctypes.POINTER(ctypes.c_char), ctypes.c_int)
     libc.bind.restype = ctypes.c_int
     bind_address = struct.pack(
-        '<HHH', socket.AF_BLUETOOTH, adapter_index, HCI_CHANNEL_USER
+        # pylint: disable=no-member
+        '<HHH',
+        socket.AF_BLUETOOTH,
+        adapter_index,
+        HCI_CHANNEL_USER,
     )
     if (
         libc.bind(
@@ -85,11 +93,11 @@ async def open_hci_socket_transport(spec):
         raise IOError(ctypes.get_errno(), os.strerror(ctypes.get_errno()))
 
     class HciSocketSource(ParserSource):
-        def __init__(self, socket):
+        def __init__(self, hci_socket):
             super().__init__()
-            self.socket = socket
+            self.socket = hci_socket
             asyncio.get_running_loop().add_reader(
-                socket.fileno(), self.recv_until_would_block
+                self.socket.fileno(), self.recv_until_would_block
             )
 
         def recv_until_would_block(self):
@@ -107,8 +115,8 @@ async def open_hci_socket_transport(spec):
             asyncio.get_running_loop().remove_reader(self.socket.fileno())
 
     class HciSocketSink:
-        def __init__(self, socket):
+        def __init__(self, hci_socket):
-            self.socket = socket
+            self.socket = hci_socket
             self.packets = collections.deque()
             self.writer_added = False
 
@@ -127,10 +135,13 @@ async def open_hci_socket_transport(spec):
                     break
 
             if self.packets:
-                # There's still something to send, ensure that we are monitoring the socket
+                # There's still something to send, ensure that we are monitoring the
+                # socket
                 if not self.writer_added:
                     asyncio.get_running_loop().add_writer(
-                        socket.fileno(), self.send_until_would_block
+                        # pylint: disable=no-member
+                        self.socket.fileno(),
+                        self.send_until_would_block,
                     )
                     self.writer_added = True
             else:
@@ -148,9 +159,9 @@ async def open_hci_socket_transport(spec):
                 asyncio.get_running_loop().remove_writer(self.socket.fileno())
 
     class HciSocketTransport(Transport):
-        def __init__(self, socket, source, sink):
+        def __init__(self, hci_socket, source, sink):
             super().__init__(source, sink)
-            self.socket = socket
+            self.socket = hci_socket
 
         async def close(self):
             logger.debug('closing HCI socket transport')

bumble/transport/pty.py

@@ -47,11 +47,11 @@ async def open_pty_transport(spec):
     tty.setraw(replica)
 
     read_transport, packet_source = await asyncio.get_running_loop().connect_read_pipe(
-        lambda: StreamPacketSource(), io.open(primary, 'rb', closefd=False)
+        StreamPacketSource, io.open(primary, 'rb', closefd=False)
     )
 
     write_transport, _ = await asyncio.get_running_loop().connect_write_pipe(
-        lambda: asyncio.BaseProtocol(), io.open(primary, 'wb', closefd=False)
+        asyncio.BaseProtocol, io.open(primary, 'wb', closefd=False)
     )
     packet_sink = StreamPacketSink(write_transport)
 

bumble/transport/pyusb.py

@@ -17,10 +17,11 @@
 # -----------------------------------------------------------------------------
 import asyncio
 import logging
-import usb.core
-import usb.util
 import threading
 import time
+
+import usb.core
+import usb.util
 from colors import color
 
 from .common import Transport, ParserSource
@@ -48,6 +49,7 @@ async def open_pyusb_transport(spec):
     04b4:f901 --> the BT USB dongle with vendor=04b4 and product=f901
     '''
 
+    # pylint: disable=invalid-name
     USB_RECIPIENT_DEVICE = 0x00
     USB_REQUEST_TYPE_CLASS = 0x01 << 5
     USB_ENDPOINT_EVENTS_IN = 0x81
@@ -108,7 +110,7 @@ async def open_pyusb_transport(spec):
         def run(self):
             while self.stop_event is None:
                 time.sleep(1)
-            self.loop.call_soon_threadsafe(lambda: self.stop_event.set())
+            self.loop.call_soon_threadsafe(self.stop_event.set)
 
     class UsbPacketSource(asyncio.Protocol, ParserSource):
         def __init__(self, device, sco_enabled):
@@ -116,6 +118,7 @@ async def open_pyusb_transport(spec):
             self.device = device
             self.loop = asyncio.get_running_loop()
             self.queue = asyncio.Queue()
+            self.dequeue_task = None
             self.event_thread = threading.Thread(
                 target=self.run, args=(USB_ENDPOINT_EVENTS_IN, hci.HCI_EVENT_PACKET)
             )
@@ -134,8 +137,8 @@ async def open_pyusb_transport(spec):
                 )
                 self.sco_thread.stop_event = None
 
-        def data_received(self, packet):
+        def data_received(self, data):
-            self.parser.feed_data(packet)
+            self.parser.feed_data(data)
 
         def enqueue(self, packet):
             self.queue.put_nowait(packet)
@@ -179,16 +182,17 @@ async def open_pyusb_transport(spec):
                 except usb.core.USBTimeoutError:
                     continue
                 except usb.core.USBError:
-                    # Don't log this: because pyusb doesn't really support multiple threads
+                    # Don't log this: because pyusb doesn't really support multiple
-                    # reading at the same time, we can get occasional USBError(errno=5)
+                    # threads reading at the same time, we can get occasional
-                    # Input/Output errors reported, but they seem to be harmless.
+                    # USBError(errno=5) Input/Output errors reported, but they seem to
+                    # be harmless.
                     # Until support for async or multi-thread support is added to pyusb,
                     # we'll just live with this as is...
                     # logger.warning(f'USB read error: {error}')
                     time.sleep(1)  # Sleep one second to avoid busy looping
 
             stop_event = current_thread.stop_event
-            self.loop.call_soon_threadsafe(lambda: stop_event.set())
+            self.loop.call_soon_threadsafe(stop_event.set)
 
     class UsbTransport(Transport):
         def __init__(self, device, source, sink):
@@ -200,16 +204,22 @@ async def open_pyusb_transport(spec):
             await self.sink.stop()
             usb.util.release_interface(self.device, 0)
 
+    usb_find = usb.core.find
+    try:
+        import libusb_package
+    except ImportError:
+        logger.debug('libusb_package is not available')
+    else:
+        usb_find = libusb_package.find
+
     # Find the device according to the spec moniker
     if ':' in spec:
         vendor_id, product_id = spec.split(':')
-        device = usb.core.find(
+        device = usb_find(idVendor=int(vendor_id, 16), idProduct=int(product_id, 16))
-            idVendor=int(vendor_id, 16), idProduct=int(product_id, 16)
-        )
     else:
         device_index = int(spec)
         devices = list(
-            usb.core.find(
+            usb_find(
                 find_all=1,
                 bDeviceClass=USB_DEVICE_CLASS_WIRELESS_CONTROLLER,
                 bDeviceSubClass=USB_DEVICE_SUBCLASS_RF_CONTROLLER,
@@ -242,6 +252,7 @@ async def open_pyusb_transport(spec):
 
     # Select an alternate setting for SCO, if available
     sco_enabled = False
+    # pylint: disable=line-too-long
     # NOTE: this is disabled for now, because SCO with alternate settings is broken,
     # see: https://github.com/libusb/libusb/issues/36
     #

bumble/transport/serial.py

@@ -60,7 +60,7 @@ async def open_serial_transport(spec):
         device = spec
     serial_transport, packet_source = await serial_asyncio.create_serial_connection(
         asyncio.get_running_loop(),
-        lambda: StreamPacketSource(),
+        StreamPacketSource,
         device,
         baudrate=speed,
         rtscts=rtscts,

bumble/transport/tcp_client.py

@@ -37,13 +37,13 @@ async def open_tcp_client_transport(spec):
     '''
 
     class TcpPacketSource(StreamPacketSource):
-        def connection_lost(self, error):
+        def connection_lost(self, exc):
-            logger.debug(f'connection lost: {error}')
+            logger.debug(f'connection lost: {exc}')
-            self.terminated.set_result(error)
+            self.terminated.set_result(exc)
 
     remote_host, remote_port = spec.split(':')
     tcp_transport, packet_source = await asyncio.get_running_loop().create_connection(
-        lambda: TcpPacketSource(),
+        TcpPacketSource,
         host=remote_host,
         port=int(remote_port),
     )

bumble/transport/tcp_server.py

@@ -49,8 +49,8 @@ async def open_tcp_server_transport(spec):
 
         # Called when a new connection is established
         def connection_made(self, transport):
-            peername = transport.get_extra_info('peername')
+            peer_name = transport.get_extra_info('peer_name')
-            logger.debug('connection from {}'.format(peername))
+            logger.debug(f'connection from {peer_name}')
             self.packet_sink.transport = transport
 
         # Called when the client is disconnected

bumble/transport/udp.py

@@ -57,7 +57,7 @@ async def open_udp_transport(spec):
         udp_transport,
         packet_source,
     ) = await asyncio.get_running_loop().create_datagram_endpoint(
-        lambda: UdpPacketSource(),
+        UdpPacketSource,
         local_addr=(local_host, int(local_port)),
         remote_addr=(remote_host, int(remote_port)),
     )

bumble/transport/usb.py

@@ -17,9 +17,12 @@
 # -----------------------------------------------------------------------------
 import asyncio
 import logging
-import usb1
 import threading
 import collections
+import ctypes
+import platform
+
+import usb1
 from colors import color
 
 from .common import Transport, ParserSource
@@ -33,6 +36,30 @@ logger = logging.getLogger(__name__)
 
 
 # -----------------------------------------------------------------------------
+def load_libusb():
+    '''
+    Attempt to load the libusb-1.0 C library from libusb_package in site-packages.
+    If the library exists, we create a DLL object and initialize the usb1 backend.
+    This only needs to be done once, but before a usb1.USBContext is created.
+    If the library does not exists, do nothing and usb1 will search default system paths
+    when usb1.USBContext is created.
+    '''
+    try:
+        import libusb_package
+    except ImportError:
+        logger.debug('libusb_package is not available')
+    else:
+        if libusb_path := libusb_package.get_library_path():
+            logger.debug(f'loading libusb library at {libusb_path}')
+            dll_loader = (
+                ctypes.WinDLL if platform.system() == 'Windows' else ctypes.CDLL
+            )
+            libusb_dll = dll_loader(
+                str(libusb_path), use_errno=True, use_last_error=True
+            )
+            usb1.loadLibrary(libusb_dll)
+
+
 async def open_usb_transport(spec):
     '''
     Open a USB transport.
@@ -44,21 +71,26 @@ async def open_usb_transport(spec):
     With <index> as the 0-based index to select amongst all the devices that appear
     to be supporting Bluetooth HCI (0 being the first one), or
     Where <vendor> and <product> are the vendor ID and product ID in hexadecimal. The
-    /<serial-number> suffix or #<index> suffix max be specified when more than one device with
+    /<serial-number> suffix or #<index> suffix max be specified when more than one
-    the same vendor and product identifiers are present.
+    device with the same vendor and product identifiers are present.
 
-    In addition, if the moniker ends with the symbol "!", the device will be used in "forced" mode:
+    In addition, if the moniker ends with the symbol "!", the device will be used in
-    the first USB interface of the device will be used, regardless of the interface class/subclass.
+    "forced" mode:
-    This may be useful for some devices that use a custom class/subclass but may nonetheless work as-is.
+    the first USB interface of the device will be used, regardless of the interface
+    class/subclass.
+    This may be useful for some devices that use a custom class/subclass but may
+    nonetheless work as-is.
 
     Examples:
     0 --> the first BT USB dongle
     04b4:f901 --> the BT USB dongle with vendor=04b4 and product=f901
     04b4:f901#2 --> the third USB device with vendor=04b4 and product=f901
-    04b4:f901/00E04C239987 --> the BT USB dongle with vendor=04b4 and product=f901 and serial number 00E04C239987
+    04b4:f901/00E04C239987 --> the BT USB dongle with vendor=04b4 and product=f901 and
+    serial number 00E04C239987
     usb:0B05:17CB! --> the BT USB dongle vendor=0B05 and product=17CB, in "forced" mode.
     '''
 
+    # pylint: disable=invalid-name
     USB_RECIPIENT_DEVICE = 0x00
     USB_REQUEST_TYPE_CLASS = 0x01 << 5
     USB_DEVICE_CLASS_DEVICE = 0x00
@@ -109,6 +141,7 @@ async def open_usb_transport(spec):
             status = transfer.getStatus()
             # logger.debug(f'<<< USB out transfer callback: status={status}')
 
+            # pylint: disable=no-member
             if status == usb1.TRANSFER_COMPLETED:
                 self.loop.call_soon_threadsafe(self.on_packet_sent_)
             elif status == usb1.TRANSFER_CANCELLED:
@@ -149,15 +182,20 @@ async def open_usb_transport(spec):
             else:
                 logger.warning(color(f'unsupported packet type {packet_type}', 'red'))
 
-        async def close(self):
+        def close(self):
             self.closed = True
 
+        async def terminate(self):
+            if not self.closed:
+                self.close()
+
             # Empty the packet queue so that we don't send any more data
             self.packets.clear()
 
             # If we have a transfer in flight, cancel it
             if self.transfer.isSubmitted():
-                # Try to cancel the transfer, but that may fail because it may have already completed
+                # Try to cancel the transfer, but that may fail because it may have
+                # already completed
                 try:
                     self.transfer.cancel()
 
@@ -176,12 +214,15 @@ async def open_usb_transport(spec):
             self.events_in = events_in
             self.loop = asyncio.get_running_loop()
             self.queue = asyncio.Queue()
+            self.dequeue_task = None
             self.closed = False
             self.event_loop_done = self.loop.create_future()
             self.cancel_done = {
                 hci.HCI_EVENT_PACKET: self.loop.create_future(),
                 hci.HCI_ACL_DATA_PACKET: self.loop.create_future(),
             }
+            self.events_in_transfer = None
+            self.acl_in_transfer = None
 
             # Create a thread to process events
             self.event_thread = threading.Thread(target=self.run)
@@ -212,8 +253,13 @@ async def open_usb_transport(spec):
         def on_packet_received(self, transfer):
             packet_type = transfer.getUserData()
             status = transfer.getStatus()
-            # logger.debug(f'<<< USB IN transfer callback: status={status} packet_type={packet_type} length={transfer.getActualLength()}')
+            # logger.debug(
+            #     f'<<< USB IN transfer callback: status={status} '
+            #     f'packet_type={packet_type} '
+            #     f'length={transfer.getActualLength()}'
+            # )
 
+            # pylint: disable=no-member
             if status == usb1.TRANSFER_COMPLETED:
                 packet = (
                     bytes([packet_type])
@@ -247,6 +293,7 @@ async def open_usb_transport(spec):
                 self.events_in_transfer.isSubmitted()
                 or self.acl_in_transfer.isSubmitted()
             ):
+                # pylint: disable=no-member
                 try:
                     self.context.handleEvents()
                 except usb1.USBErrorInterrupted:
@@ -255,19 +302,26 @@ async def open_usb_transport(spec):
             logger.debug('USB event loop done')
             self.loop.call_soon_threadsafe(self.event_loop_done.set_result, None)
 
-        async def close(self):
+        def close(self):
             self.closed = True
+
+        async def terminate(self):
+            if not self.closed:
+                self.close()
+
             self.dequeue_task.cancel()
 
             # Cancel the transfers
             for transfer in (self.events_in_transfer, self.acl_in_transfer):
                 if transfer.isSubmitted():
-                    # Try to cancel the transfer, but that may fail because it may have already completed
+                    # Try to cancel the transfer, but that may fail because it may have
+                    # already completed
                     packet_type = transfer.getUserData()
                     try:
                         transfer.cancel()
                         logger.debug(
-                            f'waiting for IN[{packet_type}] transfer cancellation to be done...'
+                            f'waiting for IN[{packet_type}] transfer cancellation '
+                            'to be done...'
                         )
                         await self.cancel_done[packet_type]
                         logger.debug(f'IN[{packet_type}] transfer cancellation done')
@@ -298,13 +352,16 @@ async def open_usb_transport(spec):
             sink.start()
 
         async def close(self):
-            await self.source.close()
+            self.source.close()
-            await self.sink.close()
+            self.sink.close()
+            await self.source.terminate()
+            await self.sink.terminate()
             self.device.releaseInterface(self.interface)
             self.device.close()
             self.context.close()
 
     # Find the device according to the spec moniker
+    load_libusb()
     context = usb1.USBContext()
     context.open()
     try:
@@ -383,6 +440,7 @@ async def open_usb_transport(spec):
 
         # Look for the first interface with the right class and endpoints
         def find_endpoints(device):
+            # pylint: disable-next=too-many-nested-blocks
             for (configuration_index, configuration) in enumerate(device):
                 interface = None
                 for interface in configuration:
@@ -431,10 +489,13 @@ async def open_usb_transport(spec):
                                 acl_out,
                                 events_in,
                             )
-                        else:
+
-                            logger.debug(
+                        logger.debug(
-                                f'skipping configuration {configuration_index + 1} / interface {setting.getNumber()}'
+                            f'skipping configuration {configuration_index + 1} / '
-                            )
+                            f'interface {setting.getNumber()}'
+                        )
+
+            return None
 
         endpoints = find_endpoints(found)
         if endpoints is None:
@@ -452,6 +513,7 @@ async def open_usb_transport(spec):
         device = found.open()
 
         # Auto-detach the kernel driver if supported
+        # pylint: disable=no-member
         if usb1.hasCapability(usb1.CAP_SUPPORTS_DETACH_KERNEL_DRIVER):
             try:
                 logger.debug('auto-detaching kernel driver')

bumble/transport/ws_server.py

@@ -44,11 +44,13 @@ async def open_ws_server_transport(spec):
             source = ParserSource()
             sink = PumpedPacketSink(self.send_packet)
             self.connection = asyncio.get_running_loop().create_future()
+            self.server = None
 
             super().__init__(source, sink)
 
         async def serve(self, local_host, local_port):
             self.sink.start()
+            # pylint: disable-next=no-member
             self.server = await websockets.serve(
                 ws_handler=self.on_connection,
                 host=local_host if local_host != '_' else None,
@@ -58,15 +60,17 @@ async def open_ws_server_transport(spec):
 
         async def on_connection(self, connection):
             logger.debug(
-                f'new connection on {connection.local_address} from {connection.remote_address}'
+                f'new connection on {connection.local_address} '
+                f'from {connection.remote_address}'
             )
             self.connection.set_result(connection)
+            # pylint: disable=no-member
             try:
                 async for packet in connection:
-                    if type(packet) is bytes:
+                    if isinstance(packet, bytes):
                         self.source.parser.feed_data(packet)
                     else:
-                        logger.warn('discarding packet: not a BINARY frame')
+                        logger.warning('discarding packet: not a BINARY frame')
             except websockets.WebSocketException as error:
                 logger.debug(f'exception while receiving packet: {error}')
 

bumble/utils.py

@@ -19,6 +19,8 @@ import asyncio
 import logging
 import traceback
 import collections
+import sys
+from typing import Awaitable, TypeVar
 from functools import wraps
 from colors import color
 from pyee import EventEmitter
@@ -45,6 +47,7 @@ def composite_listener(cls):
     registers/deregisters all methods named `on_<event_name>` as a listener for
     the <event_name> event with an emitter.
     """
+    # pylint: disable=protected-access
 
     def register(self, emitter):
         for method_name in dir(cls):
@@ -62,7 +65,39 @@ def composite_listener(cls):
 
 
 # -----------------------------------------------------------------------------
-class CompositeEventEmitter(EventEmitter):
+_T = TypeVar('_T')
+
+
+class AbortableEventEmitter(EventEmitter):
+    def abort_on(self, event: str, awaitable: Awaitable[_T]) -> Awaitable[_T]:
+        """
+        Set a coroutine or future to abort when an event occur.
+        """
+        future = asyncio.ensure_future(awaitable)
+        if future.done():
+            return future
+
+        def on_event(*_):
+            msg = f'abort: {event} event occurred.'
+            if isinstance(future, asyncio.Task):
+                # python < 3.9 does not support passing a message on `Task.cancel`
+                if sys.version_info < (3, 9, 0):
+                    future.cancel()
+                else:
+                    future.cancel(msg)
+            else:
+                future.set_exception(asyncio.CancelledError(msg))
+
+        def on_done(_):
+            self.remove_listener(event, on_event)
+
+        self.on(event, on_event)
+        future.add_done_callback(on_done)
+        return future
+
+
+# -----------------------------------------------------------------------------
+class CompositeEventEmitter(AbortableEventEmitter):
     def __init__(self):
         super().__init__()
         self._listener = None
@@ -73,6 +108,7 @@ class CompositeEventEmitter(EventEmitter):
 
     @listener.setter
     def listener(self, listener):
+        # pylint: disable=protected-access
         if self._listener:
             # Call the deregistration methods for each base class that has them
             for cls in self._listener.__class__.mro():
@@ -136,7 +172,8 @@ class AsyncRunner:
                             await coroutine
                         except Exception:
                             logger.warning(
-                                f'{color("!!! Exception in wrapper:", "red")} {traceback.format_exc()}'
+                                f'{color("!!! Exception in wrapper:", "red")} '
+                                f'{traceback.format_exc()}'
                             )
 
                     asyncio.create_task(run())

docs/README.md

@@ -2,7 +2,7 @@ Bumble Documentation
 ====================
 
 The documentation consists of a collection of markdown text files, with the root of the file
-hierarchy at `docs/mkdocs/src`, starting with `docs/mkdocs/src/index.md`. 
+hierarchy at `docs/mkdocs/src`, starting with `docs/mkdocs/src/index.md`.
 You can read the documentation as text, with any text viewer or your favorite markdown viewer,
 or generate a static HTML "site" using `mkdocs`, which you can then open with any browser.
 
@@ -14,9 +14,9 @@ The `mkdocs` directory contains all the data (actual documentation) and metadata
 `mkdocs/mkdocs.yml` contains the site configuration.
 `mkdocs/src/` is the directory where the actual documentation text, in markdown format, is located.
 
-To build, from the project's root directory:  
+To build, from the project's root directory:
 ```
-$ mkdocs build -f docs/mkdocs/mkdocs.yml 
+$ mkdocs build -f docs/mkdocs/mkdocs.yml
 ```
 
 You can then open `docs/mkdocs/site/index.html` with any web browser.

docs/images/logo.vectornator/Document.json

@@ -1 +1 @@
-{"date":644900643.85054696,"appVersion":"4.1.5","drawing":{"modificationDate":644894800.328192,"activeArtboardIndex":0,"settings":{"outlineMode":false,"isolateActiveLayer":false,"snapToEdges":false,"snapToPoints":false,"guidesVisible":true,"snapToGrid":false,"units":"Pixels","dimensionsVisible":true,"dynamicGuides":false,"isCMYKColorPreviewEnabled":false,"undoHistoryDisabled":false,"snapToGuides":true,"drawOnlyUsingPencil":false,"whiteBackground":false,"rulersVisible":true,"isTimeLapseWatermarkDisabled":false},"artboardPaths":["Artboard0.json"],"documentVersion":"unknown"}}
+{"date":644900643.85054696,"appVersion":"4.1.5","drawing":{"modificationDate":644894800.328192,"activeArtboardIndex":0,"settings":{"outlineMode":false,"isolateActiveLayer":false,"snapToEdges":false,"snapToPoints":false,"guidesVisible":true,"snapToGrid":false,"units":"Pixels","dimensionsVisible":true,"dynamicGuides":false,"isCMYKColorPreviewEnabled":false,"undoHistoryDisabled":false,"snapToGuides":true,"drawOnlyUsingPencil":false,"whiteBackground":false,"rulersVisible":true,"isTimeLapseWatermarkDisabled":false},"artboardPaths":["Artboard0.json"],"documentVersion":"unknown"}}

docs/images/logo.vectornator/Manifest.json

@@ -1 +1 @@
-{"documentJSONFilename":"Document.json","undoHistoryJSONFilename":"UndoHistory.json","fileFormatVersion":0,"thumbnailImageFilename":"Thumbnail.png"}
+{"documentJSONFilename":"Document.json","undoHistoryJSONFilename":"UndoHistory.json","fileFormatVersion":0,"thumbnailImageFilename":"Thumbnail.png"}

docs/images/logo_framed.vectornator/Document.json

@@ -1 +1 @@
-{"date":644900741.09290397,"appVersion":"4.1.5","drawing":{"modificationDate":644894800.328192,"activeArtboardIndex":0,"settings":{"outlineMode":false,"isolateActiveLayer":false,"snapToEdges":false,"snapToPoints":false,"guidesVisible":true,"snapToGrid":false,"units":"Pixels","dimensionsVisible":true,"dynamicGuides":false,"isCMYKColorPreviewEnabled":false,"undoHistoryDisabled":false,"snapToGuides":true,"drawOnlyUsingPencil":false,"whiteBackground":false,"rulersVisible":true,"isTimeLapseWatermarkDisabled":false},"artboardPaths":["Artboard0.json"],"documentVersion":"unknown"}}
+{"date":644900741.09290397,"appVersion":"4.1.5","drawing":{"modificationDate":644894800.328192,"activeArtboardIndex":0,"settings":{"outlineMode":false,"isolateActiveLayer":false,"snapToEdges":false,"snapToPoints":false,"guidesVisible":true,"snapToGrid":false,"units":"Pixels","dimensionsVisible":true,"dynamicGuides":false,"isCMYKColorPreviewEnabled":false,"undoHistoryDisabled":false,"snapToGuides":true,"drawOnlyUsingPencil":false,"whiteBackground":false,"rulersVisible":true,"isTimeLapseWatermarkDisabled":false},"artboardPaths":["Artboard0.json"],"documentVersion":"unknown"}}

docs/images/logo_framed.vectornator/Manifest.json

@@ -1 +1 @@
-{"documentJSONFilename":"Document.json","undoHistoryJSONFilename":"UndoHistory.json","fileFormatVersion":0,"thumbnailImageFilename":"Thumbnail.png"}
+{"documentJSONFilename":"Document.json","undoHistoryJSONFilename":"UndoHistory.json","fileFormatVersion":0,"thumbnailImageFilename":"Thumbnail.png"}

docs/mkdocs/mkdocs.yml

@@ -7,6 +7,8 @@ nav:
   - Getting Started: getting_started.md
   - Development:
     - Python Environments: development/python_environments.md
+    - Contributing: development/contributing.md
+    - Code Style: development/code_style.md
   - Use Cases:
     - Overview: use_cases/index.md
     - Use Case 1: use_cases/use_case_1.md

docs/mkdocs/requirements.txt

@@ -3,4 +3,4 @@ mkdocs == 1.4.0
 mkdocs-material == 8.5.6
 mkdocs-material-extensions == 1.0.3
 pymdown-extensions == 9.6
-mkdocstrings-python == 0.7.1
+mkdocstrings-python == 0.7.1

docs/mkdocs/src/api/examples.md

@@ -1,2 +1,2 @@
 API EXAMPLES
-============
+============

docs/mkdocs/src/api/guide.md

@@ -1,2 +1,2 @@
 API DEVELOPER GUIDE
-===================
+===================

docs/mkdocs/src/api/reference.md

@@ -16,4 +16,3 @@ Bumble Python API
 
 ### HCI_Disconnect_Command
 ::: bumble.hci.HCI_Disconnect_Command
-

docs/mkdocs/src/apps_and_tools/gg_bridge.md

@@ -1,2 +1,2 @@
 GOLDEN GATE BRIDGE
-==================
+==================

docs/mkdocs/src/apps_and_tools/hci_bridge.md

@@ -28,5 +28,3 @@ a host that send custom HCI commands that the controller may not understand.
     (through which the communication with other virtual controllers will be mediated).
 
     NOTE: this assumes you're running a Link Relay on port `10723`.
-
-

docs/mkdocs/src/apps_and_tools/index.md

@@ -11,4 +11,3 @@ These include:
   * [Golden Gate Bridge](gg_bridge.md) - a bridge between GATT and UDP to use with the Golden Gate "stack tool"
   * [Show](show.md) - Parse a file with HCI packets and print the details of each packet in a human readable form
   * [Link Relay](link_relay.md) - WebSocket relay for virtual RemoteLink instances to communicate with each other.
-

docs/mkdocs/src/apps_and_tools/link_relay.md

@@ -31,4 +31,3 @@ The WebSocket path used by a connecting client indicates which virtual "chat roo
     It is possible to connect to a "chat room" in a relay as an observer, rather than a virtual controller. In this case, a text-based console can be used to observe what is going on in the "chat room". Tools like [`wscat`](https://github.com/websockets/wscat#readme) or [`websocat`](https://github.com/vi/websocat) can be used for that.
 
     Example: `wscat --connect ws://localhost:10723/test`
-

docs/mkdocs/src/apps_and_tools/usb_probe.md

@@ -3,8 +3,8 @@ USB PROBE TOOL
 
 This tool lists all the USB devices, with details about each device.
 For each device, the different possible Bumble transport strings that can
-refer to it are listed. 
+refer to it are listed.
-If the device is known to be a Bluetooth HCI device, its identifier is printed 
+If the device is known to be a Bluetooth HCI device, its identifier is printed
 in reverse colors, and the transport names in cyan color.
 For other devices, regardless of their type, the transport names are printed
 in red. Whether that device is actually a Bluetooth device or not depends on
@@ -30,7 +30,7 @@ When running from the source distribution:
 $ python3 apps/usb-probe.py
 ```
 
-or 
+or
 
 ```
 $ python3 apps/usb-probe.py --verbose
@@ -38,7 +38,7 @@ $ python3 apps/usb-probe.py --verbose
 
 !!! example
     ```
-    $ python3 apps/usb_probe.py 
+    $ python3 apps/usb_probe.py
 
     ID 0A12:0001
     Bumble Transport Names: usb:0 or usb:0A12:0001
@@ -47,4 +47,4 @@ $ python3 apps/usb-probe.py --verbose
     Subclass/Protocol:      1/1 [Bluetooth]
     Manufacturer:           None
     Product:                USB2.0-BT
-    ```
+    ```

docs/mkdocs/src/components/controller.md

@@ -1,2 +1,2 @@
 CONTROLLER
-==========
+==========

docs/mkdocs/src/components/gatt.md

@@ -1,2 +1,2 @@
 GATT
-====
+====

docs/mkdocs/src/components/host.md

@@ -1,2 +1,2 @@
 HOST
-====
+====

docs/mkdocs/src/components/security_manager.md

@@ -1,2 +1,2 @@
 SECURITY MANAGER
-================
+================

docs/mkdocs/src/development/code_style.md

@@ -0,0 +1,43 @@
+CODE STYLE
+==========
+
+The Python code style used in this project follows the [Black code style](https://black.readthedocs.io/en/stable/the_black_code_style/current_style.html). 
+
+# Formatting
+
+For now, we are configuring the `black` formatter with the option to leave quotes unchanged.
+The preferred quote style is single quotes, which isn't a configurable option for `Black`, so we are not enforcing it. This may change in the future. 
+
+## Ignoring Commit for Git Blame
+
+The adoption of `Black` as a formatter came in late in the project, with already a large code base. As a result, a large number of files were changed in a single commit, which gets in the way of tracing authorship with `git blame`. The file `git-blame-ignore-revs` contains the commit hash of when that mass-formatting event occurred, which you can use to skip it in a `git blame` analysis:
+
+!!! example "Ignoring a commit with `git blame`"
+    ```
+    $ git blame --ignore-revs-file .git-blame-ignore-revs
+    ```
+
+# Linting
+
+The project includes a `pylint` configuration (see the `pyproject.toml` file for details). 
+The `pre-commit` checks only enforce that there are no errors. But we strongly recommend that you run the linter with warnings enabled at least, and possibly the "Refactor" ('R') and "Convention" ('C') categories as well. 
+To run the linter, use the `project.lint` invoke command. 
+
+!!! example "Running the linter with default options"
+    With the default settings, Errors and Warnings are enabled, but Refactor and Convention categories are not.
+    ```
+    $ invoke project.lint
+    ```
+
+!!! example "Running the linter with all categories"
+    ```
+    $ invoke project.lint --disable=""
+    ```
+
+# Editor/IDE Integration
+
+## Visual Studio Code
+
+The project includes a `.vscode/settings.json` file that specifies the `black` formatter and enables an editor ruler at 88 columns. 
+You may want to configure your own environment to "format on save" with `black` if you find that useful. We are not making that choice at the workspace level.
+

docs/mkdocs/src/development/contributing.md

@@ -0,0 +1,11 @@
+CONTRIBUTING TO THE PROJECT
+===========================
+
+To contribute some code to the project, you will need to submit a GitHub Pull Request (a.k.a PR). Please familiarize yourself with how that works (see [GitHub Pull Requests](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/about-pull-requests))
+
+You should follow the project's [code style](code_style.md), and pre-check your code before submitting a PR. The GitHub project is set up with some [Actions](https://github.com/features/actions) that will check that a PR passes at least the basic tests and complies with the coding style, but it is still recommended to check that for yourself before submitting a PR. 
+To run the basic checks (essentially: running the tests, the linter, and the formatter), use the `project.pre-commit` `invoke` command, and address any issues found:
+
+```
+$ invoke project.pre-commit
+```

docs/mkdocs/src/development/python_environments.md

@@ -1,11 +1,11 @@
 PYTHON ENVIRONMENTS
 ===================
 
-When you don't want to install Bumble in your main/default python environment, 
+When you don't want to install Bumble in your main/default python environment,
 using a virtual environment, where the package and its dependencies can be
 installed, isolated from the rest, may be useful.
 
-There are many flavors of python environments and dependency managers. 
+There are many flavors of python environments and dependency managers.
 This page describes a few of the most common ones.
 
 
@@ -16,7 +16,7 @@ Visit the [`venv` documentation](https://docs.python.org/3/library/venv.html) pa
 
 ## Pyenv
 
-`pyenv` lets you easily switch between multiple versions of Python. It's simple, unobtrusive, and follows the UNIX tradition of single-purpose tools that do one thing well.  
+`pyenv` lets you easily switch between multiple versions of Python. It's simple, unobtrusive, and follows the UNIX tradition of single-purpose tools that do one thing well.
 Visit the [`pyenv` site](https://github.com/pyenv/pyenv) for instructions on how to install
 and use `pyenv`
 
@@ -25,10 +25,10 @@ and use `pyenv`
 Conda is a convenient package manager and virtual environment.
 The file `environment.yml` is a Conda environment file that you can use to create
 a new Conda environment. Once created, you can simply activate this environment when
-working with Bumble.  
+working with Bumble.
 Visit the [Conda site](https://docs.conda.io/en/latest/) for instructions on how to install
 and use Conda.
-A few useful commands:  
+A few useful commands:
 
 ### Create a new `bumble` Conda environment
 ```

docs/mkdocs/src/examples/index.md

@@ -69,4 +69,4 @@ An app that connects to an RFComm server and bridges the RFComm channel to a loc
 An app that implements an RFComm server and, when a connection is received, bridges the channel to a local TCP socket
 
 ## `run_scanner.py`
-An app that scan for BLE devices and print the advertisements received.
+An app that scan for BLE devices and print the advertisements received.

docs/mkdocs/src/getting_started.md

@@ -5,18 +5,18 @@ GETTING STARTED WITH BUMBLE
 
 You need Python 3.8 or above. Python >= 3.9 is recommended, but 3.8 should be sufficient if
 necessary (there may be some optional functionality that will not work on some platforms with
-python 3.8).  
+python 3.8).
 Visit the [Python site](https://www.python.org/) for instructions on how to install Python
-for your platform.  
+for your platform.
 Throughout the documentation, when shell commands are shown, it is assumed that you can
 invoke Python as
 ```
 $ python
 ```
-If invoking python is different on your platform (it may be `python3` for example, or just `py` or `py.exe`), 
+If invoking python is different on your platform (it may be `python3` for example, or just `py` or `py.exe`),
 adjust accordingly.
 
-You may be simply using Bumble as a module for your own application or as a dependency to your own 
+You may be simply using Bumble as a module for your own application or as a dependency to your own
 module, or you may be working on modifying or contributing to the Bumble module or example code
 itself.
 
@@ -65,15 +65,17 @@ $ python -m pip install git+https://github.com/google/bumble.git@27c0551
 
 # Working On The Bumble Code
 When you work on the Bumble code itself, and run some of the tests or example apps, or import the
-module in your own code, you typically either install the package from source in "development mode" as described above, or you may choose to skip the install phase. 
+module in your own code, you typically either install the package from source in "development mode" as described above, or you may choose to skip the install phase.
+
+If you plan on contributing to the project, please read the [contributing](development/contributing.md) section.
 
 ## Without Installing
-If you prefer not to install the package (even in development mode), you can load the module directly from its location in the project. 
+If you prefer not to install the package (even in development mode), you can load the module directly from its location in the project.
 A simple way to do that is to set your `PYTHONPATH` to
 point to the root project directory, where the `bumble` subdirectory is located. You may set
 `PYTHONPATH` globally, or locally with each command line execution (on Unix-like systems).
 
-Example with a global `PYTHONPATH`, from a unix shell, when the working directory is the root 
+Example with a global `PYTHONPATH`, from a unix shell, when the working directory is the root
 directory of the project.
 
 ```bash
@@ -96,11 +98,11 @@ $ PYTHONPATH=. python examples/run_advertiser.py examples/device1.json serial:/d
 ```
 
 # Where To Go Next
-Once you've installed or downloaded Bumble, you can either start using some of the 
+Once you've installed or downloaded Bumble, you can either start using some of the
 [Bundled apps and tools](apps_and_tools/index.md), or look at the [examples](examples/index.md)
 to get a feel for how to use the APIs, and start writing your own applications.
 
 Depending on the use case you're interested in exploring, you may need to use a physical Bluetooth
 controller, like a USB dongle or a board with a Bluetooth radio. Visit the [Hardware page](hardware/index.md)
-for more information on using a physical radio, and/or the [Transports page](transports/index.md) for more 
+for more information on using a physical radio, and/or the [Transports page](transports/index.md) for more
 details on interfacing with either hardware modules or virtual controllers over various transports.

docs/mkdocs/src/hardware/index.md

@@ -1,18 +1,18 @@
 HARDWARE
 ========
 
-The Bumble Host connects to a controller over an [HCI Transport](../transports/index.md). 
+The Bumble Host connects to a controller over an [HCI Transport](../transports/index.md).
-To use a hardware controller attached to the host on which the host application is running, the transport is typically either [HCI over UART](../transports/serial.md) or [HCI over USB](../transports/usb.md). 
+To use a hardware controller attached to the host on which the host application is running, the transport is typically either [HCI over UART](../transports/serial.md) or [HCI over USB](../transports/usb.md).
-On Linux, the [VHCI Transport](../transports/vhci.md) can be used to communicate with any controller hardware managed by the operating system. Alternatively, a remote controller (a phyiscal controller attached to a remote host) can be used by connecting one of the networked transports (such as the [TCP Client transport](../transports/tcp_client.md), the [TCP Server transport](../transports/tcp_server.md) or the [UDP Transport](../transports/udp.md)) to an [HCI Bridge](../apps_and_tools/hci_bridge) bridging the network transport to a physical controller on a remote host. 
+On Linux, the [VHCI Transport](../transports/vhci.md) can be used to communicate with any controller hardware managed by the operating system. Alternatively, a remote controller (a phyiscal controller attached to a remote host) can be used by connecting one of the networked transports (such as the [TCP Client transport](../transports/tcp_client.md), the [TCP Server transport](../transports/tcp_server.md) or the [UDP Transport](../transports/udp.md)) to an [HCI Bridge](../apps_and_tools/hci_bridge) bridging the network transport to a physical controller on a remote host.
 
-In theory, any controller that is compliant with the HCI over UART or HCI over USB protocols can be used. 
+In theory, any controller that is compliant with the HCI over UART or HCI over USB protocols can be used.
 
-HCI over USB is very common, implemented by a number of commercial Bluetooth dongles. 
+HCI over USB is very common, implemented by a number of commercial Bluetooth dongles.
 
 It is also possible to use an embedded development board, running a specialized application, such as the [`HCI UART`](https://docs.zephyrproject.org/latest/samples/bluetooth/hci_uart/README.html) and [`HCI USB`](https://docs.zephyrproject.org/latest/samples/bluetooth/hci_usb/README.html) demo applications from the [Zephyr project](https://www.zephyrproject.org/), or the [`blehci`](https://mynewt.apache.org/latest/tutorials/ble/blehci_project.html) application from [mynewt/nimble](https://mynewt.apache.org/)
 
 Some specific USB dongles and embedded boards that are known to work include:
-  
+
   * [Nordic nRF52840 DK board](https://www.nordicsemi.com/Products/Development-hardware/nrf52840-dk) with the Zephyr `HCI UART` application
   * [Nordic nRF52840 DK board](https://www.nordicsemi.com/Products/Development-hardware/nrf52840-dk) with the mynewt `blehci` application
   * [Nordic nrf52840 dongle](https://www.nordicsemi.com/Products/Development-hardware/nRF52840-Dongle) with the Zephyr `HCI USB` application