The error messages you are encountering indicate that there are unclosed client sessions and connectors in your application. This typically happens when resources like HTTP sessions or WebSocket connections are not properly closed. Below are some best practices and patterns to address this issue: • HTTP Session Cleanup: Ensure that HTTP sessions are properly closed using a centralized cleanup function. For example:

async def _close_http_ctx() -> None:
    val = _ContextVar.get(None)
    if val is not None:
        logger.debug("http_session(): closing the httpclient ctx")
        await val().close()
        _ContextVar.set(None)

• WebSocket Connection Cleanup: Always close WebSocket connections in a

finally

block to ensure cleanup even if exceptions occur. For example:

finally:
    if ws is not None:
        await ws.close()

• Graceful Task Cancellation: Use utility functions like

utils.aio.gracefully_cancel()

to properly cancel tasks and clean up resources. For example:

finally:
    await utils.aio.gracefully_cancel(*tasks, wait_reconnect_task)
    tasks_group.cancel()
    tasks_group.exception()  # retrieve the exception

• Session Management: Centralize session management and ensure active sessions are closed properly. For example:

async def _close_active_session(self) -> None:
    async with self._session_lock:
        if self._active_session:
            try:
                await self._active_session.close()
            except Exception as e:
                logger.warning(f"error closing session: {e}")
            finally:
                self._active_session = None

• Key Principles: ◦ Always use

finally

blocks for cleanup. ◦ Check for

None

before closing resources. ◦ Handle exceptions during cleanup to avoid masking original errors. Implementing these patterns should help prevent unclosed client session and connector errors. If you need further assistance or have specific implementation questions, feel free to provide additional details about your setup. Sources: livekit-plugins/livekit-plugins-azure/livekit/plugins/azure/stt.py