Properly close streams on exception

src/replit_river/client_session.py

@@ -99,17 +99,22 @@ async def serve(self) -> None:
             try:
                 await self._handle_messages_from_ws()
             except ConnectionClosed:
+                if self._should_abort_streams_after_transport_failure():
+                    self._abort_all_streams()
                 if self._retry_connection_callback:
                     self._task_manager.create_task(self._retry_connection_callback())
 
                 await self._begin_close_session_countdown()
                 logger.debug("ConnectionClosed while serving", exc_info=True)
             except FailedSendingMessageException:
                 # Expected error if the connection is closed.
+                if self._should_abort_streams_after_transport_failure():
+                    self._abort_all_streams()
                 logger.debug(
                     "FailedSendingMessageException while serving", exc_info=True
                 )
             except Exception:
+                self._abort_all_streams()
                 logger.exception("caught exception at message iterator")
         except ExceptionGroup as eg:
             _, unhandled = eg.split(lambda e: isinstance(e, ConnectionClosed))

src/replit_river/server_session.py

@@ -87,6 +87,8 @@ async def serve(self) -> None:
                 try:
                     await self._handle_messages_from_ws(tg)
                 except ConnectionClosed:
+                    if self._should_abort_streams_after_transport_failure():
+                        self._abort_all_streams()
                     if self._retry_connection_callback:
                         self._task_manager.create_task(
                             self._retry_connection_callback()
@@ -96,10 +98,13 @@ async def serve(self) -> None:
                     logger.debug("ConnectionClosed while serving", exc_info=True)
                 except FailedSendingMessageException:
                     # Expected error if the connection is closed.
+                    if self._should_abort_streams_after_transport_failure():
+                        self._abort_all_streams()
                     logger.debug(
                         "FailedSendingMessageException while serving", exc_info=True
                     )
                 except Exception:
+                    self._abort_all_streams()
                     logger.exception("caught exception at message iterator")
         except ExceptionGroup as eg:
             _, unhandled = eg.split(lambda e: isinstance(e, ConnectionClosed))

src/replit_river/server_transport.py

@@ -153,18 +153,35 @@ async def _get_or_create_session(
                         close_session_callback=self._delete_session,
                     )
                 else:
-                    # If the instance id is the same, we reuse the session and assign
-                    # a new websocket to it.
-                    logger.debug(
-                        'Reuse old session with "%s" using new ws: %s',
-                        to_id,
-                        websocket.id,
-                    )
-                    try:
-                        await old_session.replace_with_new_websocket(websocket)
-                        new_session = old_session
-                    except FailedSendingMessageException as e:
-                        raise e
+                    if not await old_session.is_session_open():
+                        logger.info(
+                            'Session "%s" is not active, creating replacement '
+                            "session %s instead of reusing",
+                            to_id,
+                            session_id,
+                        )
+                        new_session = ServerSession(
+                            transport_id,
+                            to_id,
+                            session_id,
+                            websocket,
+                            self._transport_options,
+                            self._handlers,
+                            close_session_callback=self._delete_session,
+                        )
+                    else:
+                        # If the instance id is the same, we reuse the session and assign
+                        # a new websocket to it.
+                        logger.debug(
+                            'Reuse old session with "%s" using new ws: %s',
+                            to_id,
+                            websocket.id,
+                        )
+                        try:
+                            await old_session.replace_with_new_websocket(websocket)
+                            new_session = old_session
+                        except FailedSendingMessageException as e:
+                            raise e
 
             self._sessions[new_session._to_id] = new_session
 
@@ -311,5 +328,6 @@ async def _establish_handshake(
 
     async def _delete_session(self, session: Session) -> None:
         async with self._session_lock:
-            if session._to_id in self._sessions:
+            existing_session = self._sessions.get(session._to_id)
+            if existing_session is session:
                 del self._sessions[session._to_id]

src/replit_river/session.py

@@ -286,6 +286,17 @@ async def close_websocket(
         if should_retry and self._retry_connection_callback:
             self._task_manager.create_task(self._retry_connection_callback())
 
+    def _should_abort_streams_after_transport_failure(self) -> bool:
+        return self._retry_connection_callback is None
+
+    def _abort_all_streams(self) -> None:
+        """Close all active stream channels, notifying any waiting consumers."""
+        if not self._streams:
+            return
+        for stream in self._streams.values():
+            stream.close()
+        self._streams.clear()
+
     async def close(self) -> None:
         """Close the session and all associated streams."""
         logger.info(
@@ -310,9 +321,7 @@ async def close(self) -> None:
 
             # TODO: unexpected_close should close stream differently here to
             # throw exception correctly.
-            for stream in self._streams.values():
-                stream.close()
-            self._streams.clear()
+            self._abort_all_streams()
 
             self._state = SessionState.CLOSED