new adapter classes

examples/heart_rate_server.py

@@ -102,7 +102,6 @@ async def main() -> None:
         )
 
         # Notify subscribers of the current value as soon as they subscribe
-        @heart_rate_service.heart_rate_measurement_characteristic.on('subscription')
         def on_subscription(connection, notify_enabled, indicate_enabled):
             if notify_enabled or indicate_enabled:
                 AsyncRunner.spawn(
@@ -112,6 +111,10 @@ async def main() -> None:
                     )
                 )
 
+        heart_rate_service.heart_rate_measurement_characteristic.on(
+            'subscription', on_subscription
+        )
+
         # Go!
         await device.power_on()
         await device.start_advertising(auto_restart=True)

examples/run_gatt_client_and_server.py

@@ -70,13 +70,13 @@ async def main() -> None:
     descriptor = Descriptor(
         GATT_CHARACTERISTIC_USER_DESCRIPTION_DESCRIPTOR,
         Descriptor.READABLE,
-        'My Description',
+        'My Description'.encode(),
     )
-    manufacturer_name_characteristic = Characteristic(
+    manufacturer_name_characteristic = Characteristic[bytes](
         GATT_MANUFACTURER_NAME_STRING_CHARACTERISTIC,
         Characteristic.Properties.READ,
         Characteristic.READABLE,
-        "Fitbit",
+        "Fitbit".encode(),
         [descriptor],
     )
     device_info_service = Service(

examples/run_gatt_server.py

@@ -94,13 +94,13 @@ async def main() -> None:
         descriptor = Descriptor(
             GATT_CHARACTERISTIC_USER_DESCRIPTION_DESCRIPTOR,
             Descriptor.READABLE,
-            'My Description',
+            'My Description'.encode(),
         )
         manufacturer_name_characteristic = Characteristic(
             GATT_MANUFACTURER_NAME_STRING_CHARACTERISTIC,
             Characteristic.Properties.READ,
             Characteristic.READABLE,
-            'Fitbit',
+            'Fitbit'.encode(),
             [descriptor],
         )
         device_info_service = Service(

examples/run_gatt_with_adapters.py

@@ -1,4 +1,4 @@
-# Copyright 2024 Google LLC
+# Copyright 2025 Google LLC
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -18,6 +18,8 @@
 from __future__ import annotations
 import asyncio
 import dataclasses
+import functools
+import enum
 import logging
 import os
 import random
@@ -28,6 +30,8 @@ from typing import Any, List, Union
 from bumble.device import Device, Peer
 from bumble import transport
 from bumble import gatt
+from bumble import gatt_adapters
+from bumble import gatt_client
 from bumble import hci
 from bumble import core
 
@@ -36,6 +40,9 @@ from bumble import core
 SERVICE_UUID = core.UUID("50DB505C-8AC4-4738-8448-3B1D9CC09CC5")
 CHARACTERISTIC_UUID_BASE = "D901B45B-4916-412E-ACCA-0000000000"
 
+DEFAULT_CLIENT_ADDRESS = "F0:F1:F2:F3:F4:F5"
+DEFAULT_SERVER_ADDRESS = "F1:F2:F3:F4:F5:F6"
+
 
 # -----------------------------------------------------------------------------
 @dataclasses.dataclass
@@ -65,6 +72,12 @@ class CustomClass:
         return struct.pack(">II", self.a, self.b)
 
 
+# -----------------------------------------------------------------------------
+class CustomEnum(enum.IntEnum):
+    FOO = 1234
+    BAR = 5678
+
+
 # -----------------------------------------------------------------------------
 async def client(device: Device, address: hci.Address) -> None:
     print(f'=== Connecting to {address}...')
@@ -78,8 +91,8 @@ async def client(device: Device, address: hci.Address) -> None:
     print("*** Discovery complete")
 
     service = peer.get_services_by_uuid(SERVICE_UUID)[0]
-    characteristics = []
-    for index in range(1, 9):
+    characteristics: list[gatt_client.CharacteristicProxy] = []
+    for index in range(1, 10):
         characteristics.append(
             service.get_characteristics_by_uuid(
                 core.UUID(CHARACTERISTIC_UUID_BASE + f"{index:02X}")
@@ -91,59 +104,92 @@ async def client(device: Device, address: hci.Address) -> None:
         value = await characteristic.read_value()
         print(f"### {characteristic} = {value!r} ({value.hex()})")
 
+    # Subscribe to all characteristics as a raw bytes listener.
+    def on_raw_characteristic_update(characteristic, value):
+        print(f"^^^ Update[RAW] {characteristic.uuid} value = {value.hex()}")
+
+    for characteristic in characteristics:
+        await characteristic.subscribe(
+            functools.partial(on_raw_characteristic_update, characteristic)
+        )
+
+    # Function to subscribe to adapted characteristics
+    def on_adapted_characteristic_update(characteristic, value):
+        print(
+            f"^^^ Update[ADAPTED] {characteristic.uuid} value = {value!r}, "
+            f"type={type(value)}"
+        )
+
     # Static characteristic with a bytes value.
     c1 = characteristics[0]
     c1_value = await c1.read_value()
     print(f"@@@ C1 {c1} value = {c1_value!r} (type={type(c1_value)})")
     await c1.write_value("happy π day".encode("utf-8"))
+    await c1.subscribe(functools.partial(on_adapted_characteristic_update, c1))
 
     # Static characteristic with a string value.
-    c2 = gatt.UTF8CharacteristicAdapter(characteristics[1])
+    c2 = gatt_adapters.UTF8CharacteristicProxyAdapter(characteristics[1])
     c2_value = await c2.read_value()
     print(f"@@@ C2 {c2} value = {c2_value} (type={type(c2_value)})")
     await c2.write_value("happy π day")
+    await c2.subscribe(functools.partial(on_adapted_characteristic_update, c2))
 
     # Static characteristic with a tuple value.
-    c3 = gatt.PackedCharacteristicAdapter(characteristics[2], ">III")
+    c3 = gatt_adapters.PackedCharacteristicProxyAdapter(characteristics[2], ">III")
     c3_value = await c3.read_value()
     print(f"@@@ C3 {c3} value = {c3_value} (type={type(c3_value)})")
     await c3.write_value((2001, 2002, 2003))
+    await c3.subscribe(functools.partial(on_adapted_characteristic_update, c3))
 
     # Static characteristic with a named tuple value.
-    c4 = gatt.MappedCharacteristicAdapter(
+    c4 = gatt_adapters.MappedCharacteristicProxyAdapter(
         characteristics[3], ">III", ["f1", "f2", "f3"]
     )
     c4_value = await c4.read_value()
     print(f"@@@ C4 {c4} value = {c4_value} (type={type(c4_value)})")
     await c4.write_value({"f1": 4001, "f2": 4002, "f3": 4003})
+    await c4.subscribe(functools.partial(on_adapted_characteristic_update, c4))
 
     # Static characteristic with a serializable value.
-    c5 = gatt.SerializableCharacteristicAdapter(
+    c5 = gatt_adapters.SerializableCharacteristicProxyAdapter(
         characteristics[4], CustomSerializableClass
     )
     c5_value = await c5.read_value()
     print(f"@@@ C5 {c5} value = {c5_value} (type={type(c5_value)})")
     await c5.write_value(CustomSerializableClass(56, 57))
+    await c5.subscribe(functools.partial(on_adapted_characteristic_update, c5))
 
     # Static characteristic with a delegated value.
-    c6 = gatt.DelegatedCharacteristicAdapter(
+    c6 = gatt_adapters.DelegatedCharacteristicProxyAdapter(
         characteristics[5], encode=CustomClass.encode, decode=CustomClass.decode
     )
     c6_value = await c6.read_value()
     print(f"@@@ C6 {c6} value = {c6_value} (type={type(c6_value)})")
     await c6.write_value(CustomClass(6, 7))
+    await c6.subscribe(functools.partial(on_adapted_characteristic_update, c6))
 
     # Dynamic characteristic with a bytes value.
     c7 = characteristics[6]
     c7_value = await c7.read_value()
     print(f"@@@ C7 {c7} value = {c7_value!r} (type={type(c7_value)})")
     await c7.write_value(bytes.fromhex("01020304"))
+    await c7.subscribe(functools.partial(on_adapted_characteristic_update, c7))
 
     # Dynamic characteristic with a string value.
-    c8 = gatt.UTF8CharacteristicAdapter(characteristics[7])
+    c8 = gatt_adapters.UTF8CharacteristicProxyAdapter(characteristics[7])
     c8_value = await c8.read_value()
     print(f"@@@ C8 {c8} value = {c8_value} (type={type(c8_value)})")
     await c8.write_value("howdy")
+    await c8.subscribe(functools.partial(on_adapted_characteristic_update, c8))
+
+    # Static characteristic with an enum value
+    c9 = gatt_adapters.EnumCharacteristicProxyAdapter(
+        characteristics[8], CustomEnum, 3, 'big'
+    )
+    c9_value = await c9.read_value()
+    print(f"@@@ C9 {c9} value = {c9_value.name} (type={type(c9_value)})")
+    await c9.write_value(CustomEnum.BAR)
+    await c9.subscribe(functools.partial(on_adapted_characteristic_update, c9))
 
 
 # -----------------------------------------------------------------------------
@@ -175,142 +221,213 @@ def on_characteristic_write(characteristic: gatt.Characteristic, value: Any) ->
     print(f"<<< WRITE: {characteristic} <- {value}  ({type(value)})")
 
 
+# -----------------------------------------------------------------------------
+async def server(device: Device) -> None:
+    # Static characteristic with a bytes value.
+    c1 = gatt.Characteristic(
+        CHARACTERISTIC_UUID_BASE + "01",
+        gatt.Characteristic.Properties.READ
+        | gatt.Characteristic.Properties.WRITE
+        | gatt.Characteristic.Properties.NOTIFY,
+        gatt.Characteristic.READABLE | gatt.Characteristic.WRITEABLE,
+        b'hello',
+    )
+
+    # Static characteristic with a string value.
+    c2 = gatt_adapters.UTF8CharacteristicAdapter(
+        gatt.Characteristic(
+            CHARACTERISTIC_UUID_BASE + "02",
+            gatt.Characteristic.Properties.READ
+            | gatt.Characteristic.Properties.WRITE
+            | gatt.Characteristic.Properties.NOTIFY,
+            gatt.Characteristic.READABLE | gatt.Characteristic.WRITEABLE,
+            'hello',
+        )
+    )
+
+    # Static characteristic with a tuple value.
+    c3 = gatt_adapters.PackedCharacteristicAdapter(
+        gatt.Characteristic(
+            CHARACTERISTIC_UUID_BASE + "03",
+            gatt.Characteristic.Properties.READ
+            | gatt.Characteristic.Properties.WRITE
+            | gatt.Characteristic.Properties.NOTIFY,
+            gatt.Characteristic.READABLE | gatt.Characteristic.WRITEABLE,
+            (1007, 1008, 1009),
+        ),
+        ">III",
+    )
+
+    # Static characteristic with a named tuple value.
+    c4 = gatt_adapters.MappedCharacteristicAdapter(
+        gatt.Characteristic(
+            CHARACTERISTIC_UUID_BASE + "04",
+            gatt.Characteristic.Properties.READ
+            | gatt.Characteristic.Properties.WRITE
+            | gatt.Characteristic.Properties.NOTIFY,
+            gatt.Characteristic.READABLE | gatt.Characteristic.WRITEABLE,
+            {"f1": 3007, "f2": 3008, "f3": 3009},
+        ),
+        ">III",
+        ["f1", "f2", "f3"],
+    )
+
+    # Static characteristic with a serializable value.
+    c5 = gatt_adapters.SerializableCharacteristicAdapter(
+        gatt.Characteristic(
+            CHARACTERISTIC_UUID_BASE + "05",
+            gatt.Characteristic.Properties.READ
+            | gatt.Characteristic.Properties.WRITE
+            | gatt.Characteristic.Properties.NOTIFY,
+            gatt.Characteristic.READABLE | gatt.Characteristic.WRITEABLE,
+            CustomSerializableClass(11, 12),
+        ),
+        CustomSerializableClass,
+    )
+
+    # Static characteristic with a delegated value.
+    c6 = gatt_adapters.DelegatedCharacteristicAdapter(
+        gatt.Characteristic(
+            CHARACTERISTIC_UUID_BASE + "06",
+            gatt.Characteristic.Properties.READ
+            | gatt.Characteristic.Properties.WRITE
+            | gatt.Characteristic.Properties.NOTIFY,
+            gatt.Characteristic.READABLE | gatt.Characteristic.WRITEABLE,
+            CustomClass(1, 2),
+        ),
+        encode=CustomClass.encode,
+        decode=CustomClass.decode,
+    )
+
+    # Dynamic characteristic with a bytes value.
+    c7 = gatt.Characteristic(
+        CHARACTERISTIC_UUID_BASE + "07",
+        gatt.Characteristic.Properties.READ
+        | gatt.Characteristic.Properties.WRITE
+        | gatt.Characteristic.Properties.NOTIFY,
+        gatt.Characteristic.READABLE | gatt.Characteristic.WRITEABLE,
+        gatt.CharacteristicValue(
+            read=lambda connection: dynamic_read("bytes"),
+            write=lambda connection, value: dynamic_write("bytes", value),
+        ),
+    )
+
+    # Dynamic characteristic with a string value.
+    c8 = gatt_adapters.UTF8CharacteristicAdapter(
+        gatt.Characteristic(
+            CHARACTERISTIC_UUID_BASE + "08",
+            gatt.Characteristic.Properties.READ
+            | gatt.Characteristic.Properties.WRITE
+            | gatt.Characteristic.Properties.NOTIFY,
+            gatt.Characteristic.READABLE | gatt.Characteristic.WRITEABLE,
+            gatt.CharacteristicValue(
+                read=lambda connection: dynamic_read("string"),
+                write=lambda connection, value: dynamic_write("string", value),
+            ),
+        )
+    )
+
+    # Static characteristic with an enum value
+    c9 = gatt_adapters.EnumCharacteristicAdapter(
+        gatt.Characteristic(
+            CHARACTERISTIC_UUID_BASE + "09",
+            gatt.Characteristic.Properties.READ
+            | gatt.Characteristic.Properties.WRITE
+            | gatt.Characteristic.Properties.NOTIFY,
+            gatt.Characteristic.READABLE | gatt.Characteristic.WRITEABLE,
+            CustomEnum.FOO,
+        ),
+        cls=CustomEnum,
+        length=3,
+        byteorder='big',
+    )
+
+    characteristics: List[gatt.Characteristic] = [
+        c1,
+        c2,
+        c3,
+        c4,
+        c5,
+        c6,
+        c7,
+        c8,
+        c9,
+    ]
+
+    # Listen for read and write events.
+    for characteristic in characteristics:
+        characteristic.on(
+            "read",
+            lambda _, value, c=characteristic: on_characteristic_read(c, value),
+        )
+        characteristic.on(
+            "write",
+            lambda _, value, c=characteristic: on_characteristic_write(c, value),
+        )
+
+    device.add_service(gatt.Service(SERVICE_UUID, characteristics))
+
+    # Notify every 3 seconds
+    i = 0
+    while True:
+        await asyncio.sleep(3)
+
+        # Notifying can be done with the characteristic's current value, or
+        # by explicitly passing a value to notify with. Both variants are used
+        # here: for c1..c4 we set the value and then notify, for c4..c9 we notify
+        # with an explicit value.
+        c1.value = f'hello c1 {i}'.encode()
+        await device.notify_subscribers(c1)
+        c2.value = f'hello c2 {i}'
+        await device.notify_subscribers(c2)
+        c3.value = (1000 + i, 2000 + i, 3000 + i)
+        await device.notify_subscribers(c3)
+        c4.value = {"f1": 4000 + i, "f2": 5000 + i, "f3": 6000 + i}
+        await device.notify_subscribers(c4)
+        await device.notify_subscribers(c5, CustomSerializableClass(1000 + i, 2000 + i))
+        await device.notify_subscribers(c6, CustomClass(3000 + i, 4000 + i))
+        await device.notify_subscribers(c7, bytes([1, 2, 3, i % 256]))
+        await device.notify_subscribers(c8, f'hello c8 {i}')
+        await device.notify_subscribers(
+            c9, CustomEnum.FOO if i % 2 == 0 else CustomEnum.BAR
+        )
+
+        i += 1
+
+
 # -----------------------------------------------------------------------------
 async def main() -> None:
     if len(sys.argv) < 2:
-        print("Usage: run_gatt_with_adapters.py <transport-spec> [<bluetooth-address>]")
-        print("example: run_gatt_with_adapters.py usb:0 E1:CA:72:48:C4:E8")
+        print("Usage: run_gatt_with_adapters.py <transport-spec> client|server")
+        print("example: run_gatt_with_adapters.py usb:0 F0:F1:F2:F3:F4:F5")
         return
 
     async with await transport.open_transport(sys.argv[1]) as hci_transport:
+        is_client = sys.argv[2] == "client"
+
         # Create a device to manage the host
         device = Device.with_hci(
             "Bumble",
-            hci.Address("F0:F1:F2:F3:F4:F5"),
+            hci.Address(
+                DEFAULT_CLIENT_ADDRESS if is_client else DEFAULT_SERVER_ADDRESS
+            ),
             hci_transport.source,
             hci_transport.sink,
         )
 
-        # Static characteristic with a bytes value.
-        c1 = gatt.Characteristic(
-            CHARACTERISTIC_UUID_BASE + "01",
-            gatt.Characteristic.Properties.READ | gatt.Characteristic.Properties.WRITE,
-            gatt.Characteristic.READABLE | gatt.Characteristic.WRITEABLE,
-            b'hello',
-        )
-
-        # Static characteristic with a string value.
-        c2 = gatt.UTF8CharacteristicAdapter(
-            gatt.Characteristic(
-                CHARACTERISTIC_UUID_BASE + "02",
-                gatt.Characteristic.Properties.READ
-                | gatt.Characteristic.Properties.WRITE,
-                gatt.Characteristic.READABLE | gatt.Characteristic.WRITEABLE,
-                'hello',
-            )
-        )
-
-        # Static characteristic with a tuple value.
-        c3 = gatt.PackedCharacteristicAdapter(
-            gatt.Characteristic(
-                CHARACTERISTIC_UUID_BASE + "03",
-                gatt.Characteristic.Properties.READ
-                | gatt.Characteristic.Properties.WRITE,
-                gatt.Characteristic.READABLE | gatt.Characteristic.WRITEABLE,
-                (1007, 1008, 1009),
-            ),
-            ">III",
-        )
-
-        # Static characteristic with a named tuple value.
-        c4 = gatt.MappedCharacteristicAdapter(
-            gatt.Characteristic(
-                CHARACTERISTIC_UUID_BASE + "04",
-                gatt.Characteristic.Properties.READ
-                | gatt.Characteristic.Properties.WRITE,
-                gatt.Characteristic.READABLE | gatt.Characteristic.WRITEABLE,
-                {"f1": 3007, "f2": 3008, "f3": 3009},
-            ),
-            ">III",
-            ["f1", "f2", "f3"],
-        )
-
-        # Static characteristic with a serializable value.
-        c5 = gatt.SerializableCharacteristicAdapter(
-            gatt.Characteristic(
-                CHARACTERISTIC_UUID_BASE + "05",
-                gatt.Characteristic.Properties.READ
-                | gatt.Characteristic.Properties.WRITE,
-                gatt.Characteristic.READABLE | gatt.Characteristic.WRITEABLE,
-                CustomSerializableClass(11, 12),
-            ),
-            CustomSerializableClass,
-        )
-
-        # Static characteristic with a delegated value.
-        c6 = gatt.DelegatedCharacteristicAdapter(
-            gatt.Characteristic(
-                CHARACTERISTIC_UUID_BASE + "06",
-                gatt.Characteristic.Properties.READ
-                | gatt.Characteristic.Properties.WRITE,
-                gatt.Characteristic.READABLE | gatt.Characteristic.WRITEABLE,
-                CustomClass(1, 2),
-            ),
-            encode=CustomClass.encode,
-            decode=CustomClass.decode,
-        )
-
-        # Dynamic characteristic with a bytes value.
-        c7 = gatt.Characteristic(
-            CHARACTERISTIC_UUID_BASE + "07",
-            gatt.Characteristic.Properties.READ | gatt.Characteristic.Properties.WRITE,
-            gatt.Characteristic.READABLE | gatt.Characteristic.WRITEABLE,
-            gatt.CharacteristicValue(
-                read=lambda connection: dynamic_read("bytes"),
-                write=lambda connection, value: dynamic_write("bytes", value),
-            ),
-        )
-
-        # Dynamic characteristic with a string value.
-        c8 = gatt.UTF8CharacteristicAdapter(
-            gatt.Characteristic(
-                CHARACTERISTIC_UUID_BASE + "08",
-                gatt.Characteristic.Properties.READ
-                | gatt.Characteristic.Properties.WRITE,
-                gatt.Characteristic.READABLE | gatt.Characteristic.WRITEABLE,
-                gatt.CharacteristicValue(
-                    read=lambda connection: dynamic_read("string"),
-                    write=lambda connection, value: dynamic_write("string", value),
-                ),
-            )
-        )
-
-        characteristics: List[
-            Union[gatt.Characteristic, gatt.CharacteristicAdapter]
-        ] = [c1, c2, c3, c4, c5, c6, c7, c8]
-
-        # Listen for read and write events.
-        for characteristic in characteristics:
-            characteristic.on(
-                "read",
-                lambda _, value, c=characteristic: on_characteristic_read(c, value),
-            )
-            characteristic.on(
-                "write",
-                lambda _, value, c=characteristic: on_characteristic_write(c, value),
-            )
-
-        device.add_service(gatt.Service(SERVICE_UUID, characteristics))  # type: ignore
-
         # Get things going
         await device.power_on()
 
-        # Connect to a peer
-        if len(sys.argv) > 2:
-            await client(device, hci.Address(sys.argv[2]))
+        if is_client:
+            # Connect a client to a peer
+            await client(device, hci.Address(DEFAULT_SERVER_ADDRESS))
         else:
+            # Advertise so a peer can connect
             await device.start_advertising(auto_restart=True)
 
+            # Setup a server
+            await server(device)
+
         await hci_transport.source.wait_for_termination()