Merge pull request #473 from wnagele/BLE_support

BLE Support

Author: thebentern

.vscode/launch.json

@@ -10,7 +10,7 @@
       "request": "launch",
       "module": "meshtastic",
       "justMyCode": false,
-      "args": ["--debug", "--ble", "--device", "24:62:AB:DD:DF:3A"]
+      "args": ["--debug", "--ble", "24:62:AB:DD:DF:3A"]
     },
     {
       "name": "meshtastic admin",

TODO.md

@@ -5,7 +5,6 @@ Basic functionality is complete now.
 ## Eventual tasks
 
 - Improve documentation on properties/fields
-- change back to Bleak for BLE support - now that they fixed https://github.com/hbldh/bleak/issues/139#event-3499535304
 - include more examples: textchat.py, replymessage.py all as one little demo
 
 - possibly use tk to make a multiwindow test console: https://stackoverflow.com/questions/12351786/how-to-redirect-print-statements-to-tkinter-text-widget
@@ -17,11 +16,8 @@ Basic functionality is complete now.
 
 ## Bluetooth support
 
-(Pre-alpha level feature - you probably don't want this one yet)
-
-- This library supports connecting to Meshtastic devices over either USB (serial) or Bluetooth. Before connecting to the device you must [pair](https://docs.ubuntu.com/core/en/stacks/bluetooth/bluez/docs/reference/pairing/outbound.html) your PC with it.
-- We use the pip3 install "pygatt[GATTTOOL]"
-- ./bin/run.sh --debug --ble --device 24:62:AB:DD:DF:3A
+- ./bin/run.sh --ble-scan # To look for Meshtastic devices
+- ./bin/run.sh --ble 24:62:AB:DD:DF:3A --info
 
 ## Done
 

meshtastic/__main__.py

@@ -945,7 +945,17 @@ def common():
                 our_globals.set_logfile(logfile)
 
             subscribe()
-            if args.ble:
+            if args.ble_scan:
+                logging.debug("BLE scan starting")
+                client = BLEInterface(None, debugOut=logfile, noProto=args.noproto)
+                try:
+                    for x in client.scan():
+                        print(f"Found: name='{x[1].local_name}' address='{x[0].address}'")
+                finally:
+                    client.close()
+                meshtastic.util.our_exit("BLE scan finished", 0)
+                return
+            elif args.ble:
                 client = BLEInterface(args.ble, debugOut=logfile, noProto=args.noproto)
             elif args.host:
                 try:
@@ -1310,9 +1320,14 @@ def initParser():
 
     parser.add_argument(
         "--ble",
-        help="BLE mac address to connect to (BLE is not yet supported for this tool)",
+        help="BLE device address or name to connect to",
         default=None,
     )
+    parser.add_argument(
+        "--ble-scan",
+        help="Scan for Meshtastic BLE devices",
+        action="store_true",
+    )
 
     parser.add_argument(
         "--noproto",

meshtastic/ble.py

@@ -1,66 +1,224 @@
 """Bluetooth interface
 """
 import logging
-import platform
-
+import time
+import struct
+from threading import Thread, Event
 from meshtastic.mesh_interface import MeshInterface
 from meshtastic.util import our_exit
-
-if platform.system() == "Linux":
-    # pylint: disable=E0401
-    import pygatt
+from bleak import BleakScanner, BleakClient
+import asyncio
 
 
-# Our standard BLE characteristics
+SERVICE_UUID = "6ba1b218-15a8-461f-9fa8-5dcae273eafd"
 TORADIO_UUID = "f75c76d2-129e-4dad-a1dd-7866124401e7"
-FROMRADIO_UUID = "8ba2bcc2-ee02-4a55-a531-c525c5e454d5"
+FROMRADIO_UUID = "2c55e69e-4993-11ed-b878-0242ac120002"
 FROMNUM_UUID = "ed9da18c-a800-4f66-a670-aa7547e34453"
 
 
 class BLEInterface(MeshInterface):
-    """A not quite ready - FIXME - BLE interface to devices"""
-
-    def __init__(self, address, noProto=False, debugOut=None):
-        if platform.system() != "Linux":
-            our_exit("Linux is the only platform with experimental BLE support.", 1)
-        self.address = address
-        if not noProto:
-            self.adapter = pygatt.GATTToolBackend()  # BGAPIBackend()
-            self.adapter.start()
-            logging.debug(f"Connecting to {self.address}")
-            self.device = self.adapter.connect(address)
-        else:
-            self.adapter = None
-            self.device = None
-        logging.debug("Connected to device")
-        # fromradio = self.device.char_read(FROMRADIO_UUID)
-        MeshInterface.__init__(self, debugOut=debugOut, noProto=noProto)
-
-        self._readFromRadio()  # read the initial responses
-
-        def handle_data(handle, data):  # pylint: disable=W0613
-            self._handleFromRadio(data)
-
-        if self.device:
-            self.device.subscribe(FROMNUM_UUID, callback=handle_data)
+    class BLEError(Exception):
+        def __init__(self, message):
+            self.message = message
+            super().__init__(self.message)
+
+
+    class BLEState():
+        THREADS = False
+        BLE = False
+        MESH = False
+
+
+    def __init__(self, address, noProto = False, debugOut = None):
+        self.state = BLEInterface.BLEState()
+
+        if not address:
+            return
+
+        self.should_read = False
+
+        logging.debug("Threads starting")
+        self._receiveThread = Thread(target = self._receiveFromRadioImpl)
+        self._receiveThread_started = Event()
+        self._receiveThread_stopped = Event()
+        self._receiveThread.start()
+        self._receiveThread_started.wait(1)
+        self.state.THREADS = True
+        logging.debug("Threads running")
+
+        try:
+            logging.debug(f"BLE connecting to: {address}")
+            self.client = self.connect(address)
+            self.state.BLE = True
+            logging.debug("BLE connected")
+        except BLEInterface.BLEError as e:
+            self.close()
+            our_exit(e.message, 1)
+            return
+
+        logging.debug("Mesh init starting")
+        MeshInterface.__init__(self, debugOut = debugOut, noProto = noProto)
+        self._startConfig()
+        if not self.noProto:
+            self._waitConnected()
+            self.waitForConfig()
+        self.state.MESH = True
+        logging.debug("Mesh init finished")
+
+        logging.debug("Register FROMNUM notify callback")
+        self.client.start_notify(FROMNUM_UUID, self.from_num_handler)
+
+
+    async def from_num_handler(self, _, b):
+        from_num = struct.unpack('<I', bytes(b))[0]
+        logging.debug(f"FROMNUM notify: {from_num}")
+        self.should_read = True
+
+
+    def scan(self):
+        with BLEClient() as client:
+            return [
+                (x[0], x[1]) for x in (client.discover(
+                    return_adv = True,
+                    service_uuids = [ SERVICE_UUID ]
+                )).values()
+            ]
+
+
+    def find_device(self, address):
+        meshtastic_devices = self.scan()
+
+        addressed_devices = list(filter(lambda x: address == x[1].local_name or address == x[0].name, meshtastic_devices))
+        # If nothing is found try on the address
+        if len(addressed_devices) == 0:
+            addressed_devices = list(filter(lambda x: BLEInterface._sanitize_address(address) == BLEInterface._sanitize_address(x[0].address), meshtastic_devices))
+
+        if len(addressed_devices) == 0:
+            raise BLEInterface.BLEError(f"No Meshtastic BLE peripheral with identifier or address '{address}' found. Try --ble-scan to find it.")
+        if len(addressed_devices) > 1:
+            raise BLEInterface.BLEError(f"More than one Meshtastic BLE peripheral with identifier or address '{address}' found.")
+        return addressed_devices[0][0]
+
+    def _sanitize_address(address):
+        return address \
+            .replace("-", "") \
+            .replace("_", "") \
+            .replace(":", "") \
+            .lower()
+
+    def connect(self, address):
+        device = self.find_device(address)
+        client = BLEClient(device.address)
+        client.connect()
+        try:
+            client.pair()
+        except NotImplementedError:
+            # Some bluetooth backends do not require explicit pairing.
+            # See Bleak docs for details on this.
+            pass
+        return client
+
+
+    def _receiveFromRadioImpl(self):
+        self._receiveThread_started.set()
+        while self._receiveThread_started.is_set():
+            if self.should_read:
+                self.should_read = False
+                while True:
+                    b = bytes(self.client.read_gatt_char(FROMRADIO_UUID))
+                    if not b:
+                        break
+                    logging.debug(f"FROMRADIO read: {b.hex()}")
+                    self._handleFromRadio(b)
+            else:
+                time.sleep(0.1)
+        self._receiveThread_stopped.set()
 
     def _sendToRadioImpl(self, toRadio):
-        """Send a ToRadio protobuf to the device"""
-        # logging.debug(f"Sending: {stripnl(toRadio)}")
         b = toRadio.SerializeToString()
-        self.device.char_write(TORADIO_UUID, b)
+        if b:
+            logging.debug(f"TORADIO write: {b.hex()}")
+            self.client.write_gatt_char(TORADIO_UUID, b, response = True)
+            # Allow to propagate and then make sure we read
+            time.sleep(0.1)
+            self.should_read = True
+
 
     def close(self):
-        MeshInterface.close(self)
-        if self.adapter:
-            self.adapter.stop()
+        if self.state.MESH:
+            MeshInterface.close(self)
 
-    def _readFromRadio(self):
-        if not self.noProto:
-            wasEmpty = False
-            while not wasEmpty:
-                if self.device:
-                    b = self.device.char_read(FROMRADIO_UUID)
-                    wasEmpty = len(b) == 0
-                    if not wasEmpty:
-                        self._handleFromRadio(b)
+        if self.state.THREADS:
+            self._receiveThread_started.clear()
+            self._receiveThread_stopped.wait(5)
+        
+        if self.state.BLE:
+            self.client.disconnect()
+            self.client.close()
+
+
+class BLEClient():
+    def __init__(self, address = None, **kwargs):
+        self._eventThread = Thread(target = self._run_event_loop)
+        self._eventThread_started = Event()
+        self._eventThread_stopped = Event()
+        self._eventThread.start()
+        self._eventThread_started.wait(1)
+
+        if not address:
+            logging.debug("No address provided - only discover method will work.")
+            return
+
+        self.bleak_client = BleakClient(address, **kwargs)
+
+
+    def discover(self, **kwargs):
+        return self.async_await(BleakScanner.discover(**kwargs))
+
+    def pair(self, **kwargs):
+        return self.async_await(self.bleak_client.pair(**kwargs))
+
+    def connect(self, **kwargs):
+        return self.async_await(self.bleak_client.connect(**kwargs))
+
+    def disconnect(self, **kwargs):
+        self.async_await(self.bleak_client.disconnect(**kwargs))
+
+    def read_gatt_char(self, *args, **kwargs):
+        return self.async_await(self.bleak_client.read_gatt_char(*args, **kwargs))
+
+    def write_gatt_char(self, *args, **kwargs):
+        self.async_await(self.bleak_client.write_gatt_char(*args, **kwargs))
+
+    def start_notify(self, *args, **kwargs):
+        self.async_await(self.bleak_client.start_notify(*args, **kwargs))
+
+
+    def close(self):
+        self.async_run(self._stop_event_loop())
+        self._eventThread_stopped.wait(5)
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, type, value, traceback):
+        self.close()
+
+
+    def async_await(self, coro, timeout = None):
+        return self.async_run(coro).result(timeout)
+
+    def async_run(self, coro):
+        return asyncio.run_coroutine_threadsafe(coro, self._eventLoop)
+
+    def _run_event_loop(self):
+        self._eventLoop = asyncio.new_event_loop()
+        self._eventThread_started.set()
+        try:
+            self._eventLoop.run_forever()
+        finally:
+            self._eventLoop.close()
+        self._eventThread_stopped.set()
+
+    async def _stop_event_loop(self):
+        self._eventLoop.stop()

meshtastic/ble_interface.py

@@ -283,26 +283,6 @@ def mock_showInfo():
         mo.assert_called()
 
 
-# TODO: comment out ble (for now)
-# @pytest.mark.unit
-# def test_main_info_with_ble_interface(capsys):
-#    """Test --info"""
-#    sys.argv = ['', '--info', '--ble', 'foo']
-#    Globals.getInstance().set_args(sys.argv)
-#
-#    iface = MagicMock(autospec=BLEInterface)
-#    def mock_showInfo():
-#        print('inside mocked showInfo')
-#    iface.showInfo.side_effect = mock_showInfo
-#    with patch('meshtastic.ble_interface.BLEInterface', return_value=iface) as mo:
-#        main()
-#        out, err = capsys.readouterr()
-#        assert re.search(r'Connected to radio', out, re.MULTILINE)
-#        assert re.search(r'inside mocked showInfo', out, re.MULTILINE)
-#        assert err == ''
-#        mo.assert_called()
-
-
 @pytest.mark.unit
 @pytest.mark.usefixtures("reset_globals")
 def test_main_no_proto(capsys):

meshtastic/tests/test_ble_interface.py

@@ -18,4 +18,4 @@ pyyaml
 pytap2
 pdoc3
 pypubsub
-pygatt; platform_system == "Linux"
+bleak

meshtastic/tests/test_main.py

@@ -43,7 +43,7 @@
         "tabulate>=0.8.9",
         "timeago>=1.0.15",
         "pyyaml",
-        "pygatt>=4.0.5 ; platform_system=='Linux'",
+        "bleak>=0.21.1",
     ],
     extras_require={"tunnel": ["pytap2>=2.0.0"]},
     python_requires=">=3.7",