Remove corebluetooth global central manager.

This removes the global Application() class in the corebluetooth
backend. Instead, a new central manager is created for each scanner
object.

Since an instance of the `Application()` was created on module import,
it could interfere with other code like introspection tools that don't
actually want to run `bleak`.

This also fixes running `bleak` in threads (hbldh#206).

bleak/backends/corebluetooth/__init__.py

@@ -6,22 +6,6 @@
 
 """
 
-import asyncio
-from .CentralManagerDelegate import CentralManagerDelegate
 import objc
 
 objc.options.verbose = True
-
-
-class Application:
-    """
-    This is a temporary application class responsible for running the NSRunLoop
-    so that events within CoreBluetooth are appropriately handled
-    """
-    def __init__(self):
-        self.central_manager_delegate = CentralManagerDelegate.alloc().init()
-
-
-# Restructure this later: Global isn't the prettiest way of doing this...
-global CBAPP
-CBAPP = Application()

bleak/backends/corebluetooth/client.py

@@ -13,7 +13,6 @@
 from CoreBluetooth import CBCharacteristicWriteWithResponse, CBCharacteristicWriteWithoutResponse
 
 from bleak.backends.client import BaseBleakClient
-from bleak.backends.corebluetooth import CBAPP as cbapp
 from bleak.backends.corebluetooth.characteristic import (
     BleakGATTCharacteristicCoreBluetooth
 )
@@ -76,7 +75,8 @@ async def connect(self, **kwargs) -> bool:
 
         logger.debug("Connecting to BLE device @ {}".format(self.address))
 
-        await cbapp.central_manager_delegate.connect_(sought_device[0].details)
+        manager = self._device_info.manager().delegate()
+        await manager.connect_(sought_device[0].details)
 
         # Now get services
         await self.get_services()
@@ -85,12 +85,14 @@ async def connect(self, **kwargs) -> bool:
 
     async def disconnect(self) -> bool:
         """Disconnect from the peripheral device"""
-        await cbapp.central_manager_delegate.disconnect()
+        manager = self._device_info.manager().delegate()
+        await manager.disconnect()
         return True
 
     async def is_connected(self) -> bool:
         """Checks for current active connection"""
-        return cbapp.central_manager_delegate.isConnected
+        manager = self._device_info.manager().delegate()
+        return manager.isConnected
 
     def set_disconnected_callback(
         self, callback: Callable[[BaseBleakClient], None], **kwargs
@@ -100,8 +102,9 @@ def set_disconnected_callback(
             callback: callback to be called on disconnection.
 
         """
+        manager = self._device_info.manager().delegate()
         self._disconnected_callback = callback
-        cbapp.central_manager_delegate.disconnected_callback = self._disconnect_callback_client
+        manager.disconnected_callback = self._disconnect_callback_client
 
     def _disconnect_callback_client(self):
         """
@@ -124,16 +127,17 @@ async def get_services(self) -> BleakGATTServiceCollection:
             return self._services
 
         logger.debug("Retrieving services...")
+        manager = self._device_info.manager().delegate()
         services = (
-            await cbapp.central_manager_delegate.connected_peripheral_delegate.discoverServices()
+            await manager.connected_peripheral_delegate.discoverServices()
         )
 
         for service in services:
             serviceUUID = service.UUID().UUIDString()
             logger.debug(
                 "Retrieving characteristics for service {}".format(serviceUUID)
             )
-            characteristics = await cbapp.central_manager_delegate.connected_peripheral_delegate.discoverCharacteristics_(
+            characteristics = await manager.connected_peripheral_delegate.discoverCharacteristics_(
                 service
             )
 
@@ -144,7 +148,7 @@ async def get_services(self) -> BleakGATTServiceCollection:
                 logger.debug(
                     "Retrieving descriptors for characteristic {}".format(cUUID)
                 )
-                descriptors = await cbapp.central_manager_delegate.connected_peripheral_delegate.discoverDescriptors_(
+                descriptors = await manager.connected_peripheral_delegate.discoverDescriptors_(
                     characteristic
                 )
 
@@ -173,12 +177,13 @@ async def read_gatt_char(self, _uuid: Union[str, uuid.UUID], use_cached=False, *
             (bytearray) The read data.
 
         """
+        manager = self._device_info.manager().delegate()
         _uuid = await self.get_appropriate_uuid(str(_uuid))
         characteristic = self.services.get_characteristic(str(_uuid))
         if not characteristic:
             raise BleakError("Characteristic {} was not found!".format(_uuid))
 
-        output = await cbapp.central_manager_delegate.connected_peripheral_delegate.readCharacteristic_(
+        output = await manager.connected_peripheral_delegate.readCharacteristic_(
             characteristic.obj, use_cached=use_cached
         )
         value = bytearray(output)
@@ -198,11 +203,12 @@ async def read_gatt_descriptor(
         Returns:
             (bytearray) The read data.
         """
+        manager = self._device_info.manager().delegate()
         descriptor = self.services.get_descriptor(handle)
         if not descriptor:
             raise BleakError("Descriptor {} was not found!".format(handle))
 
-        output = await cbapp.central_manager_delegate.connected_peripheral_delegate.readDescriptor_(
+        output = await manager.connected_peripheral_delegate.readDescriptor_(
             descriptor.obj, use_cached=use_cached
         )
         if isinstance(
@@ -225,13 +231,14 @@ async def write_gatt_char(
             response (bool): If write-with-response operation should be done. Defaults to `False`.
 
         """
+        manager = self._device_info.manager().delegate()
         _uuid = await self.get_appropriate_uuid(str(_uuid))
         characteristic = self.services.get_characteristic(str(_uuid))
         if not characteristic:
             raise BleakError("Characteristic {} was not found!".format(_uuid))
 
         value = NSData.alloc().initWithBytes_length_(data, len(data))
-        success = await cbapp.central_manager_delegate.connected_peripheral_delegate.writeCharacteristic_value_type_(
+        success = await manager.connected_peripheral_delegate.writeCharacteristic_value_type_(
             characteristic.obj,
             value,
             CBCharacteristicWriteWithResponse if response else CBCharacteristicWriteWithoutResponse
@@ -253,12 +260,13 @@ async def write_gatt_descriptor(self, handle: int, data: bytearray) -> None:
             data (bytes or bytearray): The data to send.
 
         """
+        manager = self._device_info.manager().delegate()
         descriptor = self.services.get_descriptor(handle)
         if not descriptor:
             raise BleakError("Descriptor {} was not found!".format(handle))
 
         value = NSData.alloc().initWithBytes_length_(data, len(data))
-        success = await cbapp.central_manager_delegate.connected_peripheral_delegate.writeDescriptor_value_(
+        success = await manager.connected_peripheral_delegate.writeDescriptor_value_(
             descriptor.obj, value
         )
         if success:
@@ -289,12 +297,13 @@ def callback(sender, data):
             callback (function): The function to be called on notification.
 
         """
+        manager = self._device_info.manager().delegate()
         _uuid = await self.get_appropriate_uuid(str(_uuid))
         characteristic = self.services.get_characteristic(str(_uuid))
         if not characteristic:
             raise BleakError("Characteristic {0} not found!".format(_uuid))
 
-        success = await cbapp.central_manager_delegate.connected_peripheral_delegate.startNotify_cb_(
+        success = await manager.connected_peripheral_delegate.startNotify_cb_(
             characteristic.obj, callback
         )
         if not success:
@@ -311,12 +320,13 @@ async def stop_notify(self, _uuid: Union[str, uuid.UUID]) -> None:
             _uuid: The characteristic to stop notifying/indicating on.
 
         """
+        manager = self._device_info.manager().delegate()
         _uuid = await self.get_appropriate_uuid(str(_uuid))
         characteristic = self.services.get_characteristic(str(_uuid))
         if not characteristic:
             raise BleakError("Characteristic {} not found!".format(_uuid))
 
-        success = await cbapp.central_manager_delegate.connected_peripheral_delegate.stopNotify_(
+        success = await manager.connected_peripheral_delegate.stopNotify_(
             characteristic.obj
         )
         if not success:

bleak/backends/corebluetooth/discovery.py

@@ -11,7 +11,7 @@
 from asyncio.events import AbstractEventLoop
 from typing import List
 
-from bleak.backends.corebluetooth import CBAPP as cbapp
+from bleak.backends.corebluetooth.CentralManagerDelegate import CentralManagerDelegate
 from bleak.backends.device import BLEDevice
 from bleak.exc import BleakError
 
@@ -27,21 +27,21 @@ async def discover(
     """
     loop = loop if loop else asyncio.get_event_loop()
 
+    manager = CentralManagerDelegate.alloc().init()
     try:
-        await cbapp.central_manager_delegate.wait_for_powered_on(0.1)
+        await manager.wait_for_powered_on(0.1)
     except asyncio.TimeoutError:
         raise BleakError("Bluetooth device is turned off")
 
     scan_options = {"timeout": timeout}
 
-    await cbapp.central_manager_delegate.scanForPeripherals_(scan_options)
+    await manager.scanForPeripherals_(scan_options)
 
     # CoreBluetooth doesn't explicitly use MAC addresses to identify peripheral
     # devices because private devices may obscure their MAC addresses. To cope
     # with this, CoreBluetooth utilizes UUIDs for each peripheral. We'll use
     # this for the BLEDevice address on macOS
 
-
-    devices = cbapp.central_manager_delegate.devices
+    devices = manager.devices
     return list(devices.values())
 

bleak/backends/corebluetooth/scanner.py

@@ -5,7 +5,7 @@
 from asyncio.events import AbstractEventLoop
 from typing import Callable, Any, Union, List
 
-from bleak.backends.corebluetooth import CBAPP as cbapp
+from bleak.backends.corebluetooth.CentralManagerDelegate import CentralManagerDelegate
 from bleak.backends.device import BLEDevice
 from bleak.exc import BleakError
 from bleak.backends.scanner import BaseBleakScanner
@@ -41,6 +41,7 @@ def __init__(self, **kwargs):
         super(BleakScannerCoreBluetooth, self).__init__(**kwargs)
         self._callback = None
         self._identifiers = None
+        self._manager = CentralManagerDelegate.alloc().init()
         self._timeout = kwargs.get("timeout", 5.0)
 
     async def start(self):