Discovery filter

bleak/backends/scanner.py

@@ -61,6 +61,11 @@ def __repr__(self) -> str:
     Optional[Awaitable[None]],
 ]
 
+AdvertisementDataFilter = Callable[
+    [BLEDevice, Optional[AdvertisementData]],
+    bool,
+]
+
 
 class BaseBleakScanner(abc.ABC):
     """Interface for Bleak Bluetooth LE Scanners"""
@@ -195,10 +200,29 @@ async def find_device_by_address(
 
         """
         device_identifier = device_identifier.lower()
+        return await cls.find_device_by_filter(lambda d, ad : d.address.lower() == device_identifier)
+
+    @classmethod
+    async def find_device_by_filter(
+        cls, filterfunc: AdvertisementDataFilter, timeout: float = 10.0, **kwargs
+    ) -> Optional[BLEDevice]:
+        """A convenience method for obtaining a ``BLEDevice`` object specified by a filter function.
+
+        Args:
+            filterfunc (AdvertisementDataFilter): A function that is called for every BLEDevice found. It should return True only for the wanted device.
+            timeout (float): Optional timeout to wait for detection of specified peripheral before giving up. Defaults to 10.0 seconds.
+
+        Keyword Args:
+            adapter (str): Bluetooth adapter to use for discovery.
+
+        Returns:
+            The ``BLEDevice`` sought or ``None`` if not detected.
+
+        """
         stop_scanning_event = asyncio.Event()
 
         def stop_if_detected(d: BLEDevice, ad: AdvertisementData):
-            if d.address.lower() == device_identifier:
+            if filterfunc(d, ad):
                 stop_scanning_event.set()
 
         async with cls(
@@ -211,5 +235,5 @@ def stop_if_detected(d: BLEDevice, ad: AdvertisementData):
             return next(
                 d
                 for d in scanner.discovered_devices
-                if d.address.lower() == device_identifier
+                if filterfunc(d, None)
             )

examples/scanner.py

@@ -10,6 +10,7 @@
 
 import asyncio
 import platform
+import sys
 
 from bleak import BleakScanner
 
@@ -19,6 +20,8 @@
     if platform.system() != "Darwin"
     else "B9EA5233-37EF-4DD6-87A8-2A875E821C46"  # <--- Change to your device's address here if you are using macOS
 )
+if len(sys.argv) == 2:
+    address = sys.argv[1]
 
 
 async def run():

examples/scanner_byname.py

@@ -0,0 +1,30 @@
+"""
+Bleak Scanner
+-------------
+
+
+
+Updated on 2020-08-12 by hbldh <henrik.blidh@nedomkull.com>
+
+"""
+
+import asyncio
+import platform
+import sys
+
+from bleak import BleakScanner
+
+
+if len(sys.argv) != 2:
+    print(f'Usage: {sys.argv[0]} name')
+    sys.exit(1)
+wanted_name = sys.argv[1].lower()
+
+
+async def run():
+    device = await BleakScanner.find_device_by_filter(lambda d, ad : d.name and d.name.lower() == wanted_name)
+    print(device)
+
+
+loop = asyncio.get_event_loop()
+loop.run_until_complete(run())