[Python] Rosbridge Reconnection not succesfull

I have a service that is using roslibpy

class RosConnectorService(AbstractConnectorService):
def __init__(self):
self._ros_client = None
self._ros_connection_task: tasks.Task | None = None
self._ros_connected_event: asyncio.Event = asyncio.Event()


async def connect(self):
logger.debug(f"Attempting to connect to RosBridge")
retry_count = 5
self._ros_client = roslibpy.Ros(
host="localhost",
port="9090",
)

if self._ros_connected_event.is_set():
self._ros_client.close()

while True:
try:
if not self._ros_client.is_connected:
self._ros_client.on_ready(self._on_open)
self._ros_client.connect()
self._ros_connection_task = asyncio.create_task(run_in_threadpool(self._ros_client.run_forever))

await asyncio.wait_for(self._ros_connected_event.wait(), timeout=5)
break
except asyncio.TimeoutError as e:
loguru.logger.critical(f"Timeout while connecting: {e}")
retry_count = self._handle_exception(retry_count)
if retry_count <= 0:
if self._ros_connection_task and not self._ros_connection_task.cancelled():
self._ros_connection_task.cancel()
return
logger.debug(f"Retrying to connect... {retry_count} retries left.")
except ReactorAlreadyRunning:
logger.debug("Reactor already running. Skipping start.")
if not self._ros_client.is_connected:
self._ros_connected_event.set()
except Exception as e:
raise Exception(
f"Disconnected from Rosbridge. Error: {e}")

def _handle_exception(self, retry_count: int) -> int:
retry_count -= 1
loguru.logger.error(
f"Failed to connect to Rosbridge. "
f"Retry in 5 seconds")

if retry_count == 0:
raise Exception(
f"Failed to connect to Rosbridge after {retry_count} attempts."
f"Please check your internet connection")
return retry_count

def _on_open(self) -> None:
logger.debug("Connection to ROSBridge successfully established.")
self._ros_connected_event.set()

async def disconnect(self):
logger.debug("Disconnecting from ROSBridge.")

if self._ros_connection_task:
if not self._ros_connection_task.done():
self._ros_connection_task.cancel()
try:
await self._ros_connection_task
except asyncio.CancelledError:
logger.debug("ROS connection task successfully cancelled.")

if self._ros_client:
self._ros_client.close()
self._ros_client = None

self._ros_connected_event.clear()
self._ros_connected_event = asyncio.Event()


This service is injected in another service and is called when starting a certain process

class TestService(AbstractTestService):
def __init__(self, ros_connector_service: AbstractConnectorService):
self.ros_connector_service: AbstractConnectorService = ros_connector_service
self.thread: Thread | None = None
self.stop_event: Event = Event()
self.lock: Lock = Lock()
self.status: str = "idle"

def start(self):
if self.thread and self.thread.is_alive():
logger.warning("Resource busy.")
return

with self.lock:
self.status = "running"
self.stop_event.clear()
self.thread = Thread(target=self._run_async_task)
self.thread.start()

def _run_async_task(self):
asyncio.run(self._start_host())

async def _start_host(self) -> None:
await self.ros_connector_service.connect()

try:
await self.ros_connector_service.toggle_topic(True)

except Exception as e:
raise Exception(detail=f"Error during process: {e}")

finally:
with self.lock:
self.status = "idle"
await self.ros_connector_service.toggle_topic(False)
await self.ros_connector_service.disconnect()


When I start the app and run my start function in the ping service, everything is working fine. However, when i terminate the process and restart a new process, im getting this error:

Task exception was never retrieved
future: <Task finished name='Task-16' coro=<run_in_threadpool() done, defined at /home/user/projectPython/.venv/lib/python3.10/site-packages/starlette/concurrency.py:35> exception=ReactorAlreadyRunning()>
Traceback (most recent call last):
File "/home/user/projectPython/.venv/lib/python3.10/site-packages/starlette/concurrency.py", line 39, in run_in_threadpool
return await anyio.to_thread.run_sync(func, *args)
File "/home/user/projectPython/.venv/lib/python3.10/site-packages/anyio/to_thread.py", line 56, in run_sync
return await get_async_backend().run_sync_in_worker_thread(
File "/home/user/projectPython/.venv/lib/python3.10/site-packages/anyio/_backends/_asyncio.py", line 2461, in run_sync_in_worker_thread
return await future
File "/home/user/projectPython/.venv/lib/python3.10/site-packages/anyio/_backends/_asyncio.py", line 962, in run
result = context.run(func, *args)
File "/home/user/projectPython/.venv/lib/python3.10/site-packages/roslibpy/ros.py", line 114, in run_forever
self.factory.manager.run_forever()
File "/home/user/projectPython/.venv/lib/python3.10/site-packages/roslibpy/comm/comm_autobahn.py", line 190, in run_forever
reactor.run()
File "/home/user/projectPython/.venv/lib/python3.10/site-packages/twisted/internet/base.py", line 695, in run
self.startRunning(installSignalHandlers=installSignalHandlers)
File "/home/user/projectPython/.venv/lib/python3.10/site-packages/twisted/internet/base.py", line 924, in startRunning
raise error.ReactorAlreadyRunning()
twisted.internet.error.ReactorAlreadyRunning


And then this one if i try to reconnect again

2025-03-19 12:32:57.081 | ERROR | core.application.services.ros_connector_service:connect:64 - Disconnected from Rosbridge. Error: <asyncio.locks.Event object at 0x70ce46bc4f40 [unset]> is bound to a different event loop
Traceback (most recent call last):
File "/home/user/projectPython/src/core/application/services/ros_connector_service.py", line 49, in connect
await asyncio.wait_for(self._ros_connected_event.wait(), timeout=constants.CONNECTOR_DELAY_CONNECTION)
File "/usr/lib/python3.10/asyncio/tasks.py", line 445, in wait_for
return fut.result()
File "/usr/lib/python3.10/asyncio/locks.py", line 211, in wait
fut = self._get_loop().create_future()
File "/usr/lib/python3.10/asyncio/mixins.py", line 30, in _get_loop
raise RuntimeError(f'{self!r} is bound to a different event loop')
RuntimeError: <asyncio.locks.Event object at 0x70ce46bc4f40 [unset]> is bound to a different event loop
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/usr/lib/python3.10/threading.py", line 953, in run
self._target(*self._args, **self._kwargs)
File "/home/user/projectPython/src/core/application/services/ping_service.py", line 64, in _run_async_task
asyncio.run(self._ping_host(host_ip))
File "/usr/lib/python3.10/asyncio/runners.py", line 44, in run
return loop.run_until_complete(main)
File "/usr/lib/python3.10/asyncio/base_events.py", line 649, in run_until_complete
return future.result()
File "/home/user/projectPython/src/core/application/services/ping_service.py", line 93, in _ping_host
await self.ros_connector_service.connect()
File "/home/user/projectPython/src/core/application/services/ros_connector_service.py", line 68, in connect
raise DisconnectionFromWebsocketException(
core.domain.exceptions.base_exceptions: Disconnected from Rosbridge. Error: <asyncio.locks.Event object at 0x70ce46bc4f40 [unset]> is bound to a different event loop
Exception in thread Thread-7 (_run_async_task):
Traceback (most recent call last):
File "/home/user/projectPython/src/core/application/services/ros_connector_service.py", line 49, in connect
await asyncio.wait_for(self._ros_connected_event.wait(), timeout=constants.CONNECTOR_DELAY_CONNECTION)
File "/usr/lib/python3.10/asyncio/tasks.py", line 445, in wait_for
return fut.result()
File "/usr/lib/python3.10/asyncio/locks.py", line 211, in wait
fut = self._get_loop().create_future()
File "/usr/lib/python3.10/asyncio/mixins.py", line 30, in _get_loop
raise RuntimeError(f'{self!r} is bound to a different event loop')
RuntimeError: <asyncio.locks.Event object at 0x70ce46bc4f40 [unset]> is bound to a different event loop
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "/usr/lib/python3.10/threading.py", line 1016, in _bootstrap_inner
self.run()
File "/usr/lib/python3.10/threading.py", line 953, in run
self._target(*self._args, **self._kwargs)
File "/home/user/projectPython/src/core/application/services/ping_service.py", line 64, in _run_async_task
asyncio.run(self._ping_host(host_ip))
File "/usr/lib/python3.10/asyncio/runners.py", line 44, in run
return loop.run_until_complete(main)
File "/usr/lib/python3.10/asyncio/base_events.py", line 649, in run_until_complete
return future.result()
File "/home/user/projectPython/src/core/application/services/ping_service.py", line 93, in _ping_host
await self.ros_connector_service.connect()
Disconnected from Rosbridge. Error: <asyncio.locks.Event object at 0x70ce46bc4f40 [unset]> is bound to a different event loop

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