Fix a bug to correctly cleanup after sending "Stop App" message. This allows a server to correctly handle the next client

Author: dieriver

simulaqron/netqasm_backend/qnodeos.py

@@ -3,9 +3,10 @@
 from typing import Optional, Dict, Callable, Generator, Any, List, Type
 
 from netqasm.backend.executor import Executor
-from netqasm.backend.messages import MsgDoneMessage, Message, MessageType
+from netqasm.backend.messages import MsgDoneMessage, Message, MessageType, StopAppMessage
 from netqasm.backend.qnodeos import QNodeController
 from netqasm.lang.instr import Flavour
+from netqasm.sdk.shared_memory import SharedMemoryManager
 from twisted.internet.defer import inlineCallbacks
 from twisted.internet.protocol import Protocol
 
@@ -173,6 +174,11 @@ def _return_qubit_state(self, qubit_id: int, real_part: List[List[float]], imag_
         qubit_state_message = ReturnQubitStateMessage(qubit_id, real_part, imag_part)
         self._return_msg(msg=qubit_state_message)
 
+    def _handle_stop_app(self, msg: StopAppMessage) -> Generator[Any, None, None]:
+        yield from super()._handle_stop_app(msg)
+        # Clear the shared memory registries occupied in the QNodeOS backend
+        SharedMemoryManager.reset_memories()
+
     # We override the _get_message_handlers method so we can also handle the "get qubit state" message
     def _get_message_handlers(self) -> Dict[NewMessageType | MessageType, Callable]:
         return {

simulaqron/sdk/connection.py

@@ -152,6 +152,28 @@ def try_connection(
             retry_time=-1.0,
         )
 
+    def close(
+        self,
+        clear_app: bool = True,
+        stop_backend: bool = False,
+        exception: bool = False,
+    ) -> None:
+        """
+        Closes the SimulaQron connection. It also sends the corresponding messages
+        to the backend to clean up the states associated with the connection.
+        This leaves the quantum backend ready to be used with a new client.
+
+        :param clear_app: Clear the application before closing the connection.
+        :type clear_app: bool
+        :param stop_backend: Stop the backend when closing the connection.
+        :type stop_backend: bool
+        :param exception: Whether the app is stopping due to an exception or not.
+        :type exception: bool
+        """
+        super().close(clear_app, stop_backend, exception)
+        # Clear the shared memories occupied by this connection
+        SharedMemoryManager.reset_memories()
+
     @staticmethod
     def _create_socket(
             name: str,