我使用示例应用程序（https://github.com/miguelgrinberg/Flask-SocketIO/tree/master/example），它在本地Windows上启动正常，但在服务器CentOS上它失败并出现错误400。我使用Gunicorn + Nginx + Eventlet 。
日志：
2019-12-19 16:20:41,694 - INFO: 30bd9dce92f245698ae73dfec9fc0197: Sending packet MESSAGE data 0 - [in /home/venv/py37sio/lib/python3.7/site-packages/engineio/socket.py:95]
2019-12-19 16:20:41,730 - INFO: 30bd9dce92f245698ae73dfec9fc0197: Received packet MESSAGE data 0/test, - [in /home/venv/py37sio/lib/python3.7/site-packages/engineio/socket.py:52]
2019-12-19 16:20:41,731 - INFO: 30bd9dce92f245698ae73dfec9fc0197: Sending packet MESSAGE data 2/test,["my_response",{"data":"Connected","count":0}] - [in /home/venv/py37sio/lib/python3.7/site-packages/engineio/socket.py:95]
2019-12-19 16:20:41,731 - INFO: 30bd9dce92f245698ae73dfec9fc0197: Sending packet MESSAGE data 0/test - [in /home/venv/py37sio/lib/python3.7/site-packages/engineio/socket.py:95]
2019-12-19 16:20:41,732 - INFO: 30bd9dce92f245698ae73dfec9fc0197: Received request to upgrade to websocket - [in /home/venv/py37sio/lib/python3.7/site-packages/engineio/socket.py:105]
2019-12-19 16:21:12,524 - WARNING: Invalid …