Merge pull request #13 from google/gbg/standard-profiles

support for type adapters and framework for standard GATT profiles

tests/gatt_test.py

@@ -18,6 +18,7 @@
 import asyncio
 import logging
 import os
+import struct
 import pytest
 
 from bumble.controller import Controller
@@ -25,6 +26,12 @@ from bumble.link import LocalLink
 from bumble.device import Device, Peer
 from bumble.host import Host
 from bumble.gatt import (
+    GATT_BATTERY_LEVEL_CHARACTERISTIC,
+    CharacteristicAdapter,
+    DelegatedCharacteristicAdapter,
+    PackedCharacteristicAdapter,
+    MappedCharacteristicAdapter,
+    UTF8CharacteristicAdapter,
     Service,
     Characteristic,
     CharacteristicValue
@@ -91,6 +98,96 @@ def test_ATT_Read_By_Group_Type_Request():
     basic_check(pdu)
 
 
+# -----------------------------------------------------------------------------
+def test_CharacteristicAdapter():
+    # Check that the CharacteristicAdapter base class is transparent
+    v = bytes([1, 2, 3])
+    c = Characteristic(GATT_BATTERY_LEVEL_CHARACTERISTIC, Characteristic.READ, Characteristic.READABLE, v)
+    a = CharacteristicAdapter(c)
+
+    value = a.read_value(None)
+    assert(value == v)
+
+    v = bytes([3, 4, 5])
+    a.write_value(None, v)
+    assert(c.value == v)
+
+    # Simple delegated adapter
+    a = DelegatedCharacteristicAdapter(c, lambda x: bytes(reversed(x)), lambda x: bytes(reversed(x)))
+
+    value = a.read_value(None)
+    assert(value == bytes(reversed(v)))
+
+    v = bytes([3, 4, 5])
+    a.write_value(None, v)
+    assert(a.value == bytes(reversed(v)))
+
+    # Packed adapter with single element format
+    v = 1234
+    pv = struct.pack('>H', v)
+    c.value = v
+    a = PackedCharacteristicAdapter(c, '>H')
+
+    value = a.read_value(None)
+    assert(value == pv)
+    c.value = None
+    a.write_value(None, pv)
+    assert(a.value == v)
+
+    # Packed adapter with multi-element format
+    v1 = 1234
+    v2 = 5678
+    pv = struct.pack('>HH', v1, v2)
+    c.value = (v1, v2)
+    a = PackedCharacteristicAdapter(c, '>HH')
+
+    value = a.read_value(None)
+    assert(value == pv)
+    c.value = None
+    a.write_value(None, pv)
+    assert(a.value == (v1, v2))
+
+    # Mapped adapter
+    v1 = 1234
+    v2 = 5678
+    pv = struct.pack('>HH', v1, v2)
+    mapped = {'v1': v1, 'v2': v2}
+    c.value = mapped
+    a = MappedCharacteristicAdapter(c, '>HH', ('v1', 'v2'))
+
+    value = a.read_value(None)
+    assert(value == pv)
+    c.value = None
+    a.write_value(None, pv)
+    assert(a.value == mapped)
+
+    # UTF-8 adapter
+    v = 'Hello π'
+    ev = v.encode('utf-8')
+    c.value = v
+    a = UTF8CharacteristicAdapter(c)
+
+    value = a.read_value(None)
+    assert(value == ev)
+    c.value = None
+    a.write_value(None, ev)
+    assert(a.value == v)
+
+
+# -----------------------------------------------------------------------------
+def test_CharacteristicValue():
+    b = bytes([1, 2, 3])
+    c = CharacteristicValue(read=lambda _: b)
+    x = c.read(None)
+    assert(x == b)
+
+    result = []
+    c = CharacteristicValue(write=lambda connection, value: result.append((connection, value)))
+    z = object()
+    c.write(z, b)
+    assert(result == [(z, b)])
+
+
 # -----------------------------------------------------------------------------
 class TwoDevices:
     def __init__(self):
@@ -199,6 +296,56 @@ async def test_read_write():
     assert(characteristic2._last_value[1] == b)
 
 
+# -----------------------------------------------------------------------------
+@pytest.mark.asyncio
+async def test_read_write2():
+    [client, server] = TwoDevices().devices
+
+    v = bytes([0x11, 0x22, 0x33, 0x44])
+    characteristic1 = Characteristic(
+        'FDB159DB-036C-49E3-B3DB-6325AC750806',
+        Characteristic.READ | Characteristic.WRITE,
+        Characteristic.READABLE | Characteristic.WRITEABLE,
+        value=v
+    )
+
+    service1 = Service(
+        '3A657F47-D34F-46B3-B1EC-698E29B6B829',
+        [
+            characteristic1
+        ]
+    )
+    server.add_services([service1])
+
+    await client.power_on()
+    await server.power_on()
+    connection = await client.connect(server.random_address)
+    peer = Peer(connection)
+
+    await peer.discover_services()
+    c = peer.get_services_by_uuid(service1.uuid)
+    assert(len(c) == 1)
+    s = c[0]
+    await s.discover_characteristics()
+    c = s.get_characteristics_by_uuid(characteristic1.uuid)
+    assert(len(c) == 1)
+    c1 = c[0]
+
+    v1 = await c1.read_value()
+    assert(v1 == v)
+
+    a1 = PackedCharacteristicAdapter(c1, '>I')
+    v1 = await a1.read_value()
+    assert(v1 == struct.unpack('>I', v)[0])
+
+    b = bytes([0x55, 0x66, 0x77, 0x88])
+    await a1.write_value(struct.unpack('>I', b)[0])
+    await async_barrier()
+    assert(characteristic1.value == b)
+    v1 = await a1.read_value()
+    assert(v1 == struct.unpack('>I', b)[0])
+
+
 # -----------------------------------------------------------------------------
 @pytest.mark.asyncio
 async def test_subscribe_notify():
@@ -330,6 +477,7 @@ async def test_subscribe_notify():
 # -----------------------------------------------------------------------------
 async def async_main():
     await test_read_write()
+    await test_read_write2()
     await test_subscribe_notify()
 
 # -----------------------------------------------------------------------------
@@ -338,4 +486,6 @@ if __name__ == '__main__':
     test_UUID()
     test_ATT_Error_Response()
     test_ATT_Read_By_Group_Type_Request()
+    test_CharacteristicValue()
+    test_CharacteristicAdapter()
     asyncio.run(async_main())