Merge pull request #193 from dhalbert/deinit-characteristic-buffers

Deinit UARTService CharacteristicBuffers on disconnect

Author: dhalbert

adafruit_ble/__init__.py

@@ -145,6 +145,9 @@ def pair(self, *, bond: bool = True) -> None:
     def disconnect(self) -> None:
         """Disconnect from peer."""
         self._bleio_connection.disconnect()
+        # Clean up any services that need explicit cleanup.
+        for service in self._constructed_services.values():
+            service.deinit()
 
 
 class BLERadio:

adafruit_ble/characteristics/stream.py

@@ -69,7 +69,9 @@ def __init__(
             uuid=uuid, properties=properties, read_perm=read_perm, write_perm=write_perm
         )
 
-    def bind(self, service: Service) -> Union[_bleio.Characteristic, BoundWriteStream]:
+    def bind(
+        self, service: Service
+    ) -> Union[_bleio.CharacteristicBuffer, BoundWriteStream]:
         """Binds the characteristic to the given Service."""
         bound_characteristic = super().bind(service)
         # If we're given a remote service then we're the client and need to buffer in.

adafruit_ble/services/__init__.py

@@ -82,6 +82,9 @@ def __init__(
                 else:
                     getattr(self, class_attr)
 
+    def deinit(self):
+        """Override this method to do any explicit cleanup necessary on connection close."""
+
     @property
     def remote(self) -> bool:
         """True if the service is provided by a peer and accessed remotely."""

adafruit_ble/services/nordic.py

@@ -62,6 +62,14 @@ def __init__(self, service: Optional[_bleio.Service] = None) -> None:
             self._tx = self._server_rx
             self._rx = self._server_tx
 
+    def deinit(self):
+        """The characteristic buffers must be deinitialized when no longer needed.
+        Otherwise they will leak storage.
+        """
+        for obj in (self._tx, self._rx):
+            if hasattr(obj, "deinit"):
+                obj.deinit()
+
     def read(self, nbytes: Optional[int] = None) -> Optional[bytes]:
         """
         Read characters. If ``nbytes`` is specified then read at most that many bytes.