problems on updating from polling to websocket

[ReimarBauer]

Something blocks our server to upgrade the protocoll for socketIO

/socket.io/?transport=polling  HTTP/1.1" 200 97
/socket.io/?transport=websocket HTTP/1.1" None 0
/socket.io/?transport=websocket HTTP/1.1" 500 0

When it is solved it needs documetations.

[ReimarBauer]

    raise value
  File "/home/mss-mscolab/mambaforge/envs/mssenv/lib/python3.9/site-packages/gunicorn/workers/sync.py", line 184, in handle_request
    resp.write(item)
  File "/home/mss-mscolab/mambaforge/envs/mssenv/lib/python3.9/site-packages/gunicorn/http/wsgi.py", line 326, in write
    self.send_headers()
  File "/home/mss-mscolab/mambaforge/envs/mssenv/lib/python3.9/site-packages/gunicorn/http/wsgi.py", line 322, in send_headers
    util.write(self.sock, util.to_bytestring(header_str, "latin-1"))
  File "/home/mss-mscolab/mambaforge/envs/mssenv/lib/python3.9/site-packages/gunicorn/util.py", line 299, in write
    sock.sendall(data)
OSError: [Errno 9] Bad file descriptor

sound similiar https://github.com/benoitc/gunicorn/issues/3025

[ReimarBauer]

We have to verify if we can use this as workaround https://github.com/benoitc/gunicorn/issues/3058

[ReimarBauer]

gunicorn had a new release