AttributeError: 'NoneType' object has no attribute 'cancel'

[julien-duponchelle]

https://sentry.io/gns3/gns3-server/issues/235755086/

AttributeError: 'NoneType' object has no attribute 'cancel'
(2 additional frame(s) were not displayed)
...
  File "gns3server/controller/compute.py", line 580, in forward
    res = yield from self.http_query(method, "/{}/{}".format(type, path), data=data, timeout=None)
  File "gns3server/controller/compute.py", line 361, in http_query
    response = yield from self._run_http_query(method, path, data=data, **kwargs)
  File "gns3server/controller/compute.py", line 502, in _run_http_query
    response = yield from self._session().request(method, url, headers=headers, data=data, auth=self._auth, chunked=chunked, timeout=timeout)
  File "aiohttp/client.py", line 583, in __iter__
    resp = yield from self._coro
  File "aiohttp/client.py", line 279, in _request
    resp.connection.add_callback(handle.cancel)

AttributeError: 'NoneType' object has no attribute 'cancel'

[julien-duponchelle]

Need deep debug, seem an issue inside aiohttp

[julien-duponchelle]

It's an aiohttp issue they will release a fix:
aio-libs/aiohttp#1720