I'm trying to run a client an server in python using flask_socketio, socketIO_client and SOCKET.IO in a raspberry pi 4 but I'm getting the following error:

The client is using an unsupported version of the Socket.IO or Engine.IO protocols (further occurrences of this error will be logged with level INFO)
192.168.1.80 - - [05/Feb/2021 18:30:41] "GET /socket.io/?EIO=3&transport=polling&t=NTpTT-L HTTP/1.1" 400 219 0.000618

These are my current versions:

pi@raspberrypi:~/Desktop/EDAdataLogger $ npm list socket.io EDAdataLogger@ /home/pi/Desktop/EDAdataLogger └── socket.io@3.1.1

pi@raspberrypi:~/Desktop/EDAdataLogger $ npm list socket.io-client EDAdataLogger@ /home/pi/Desktop/EDAdataLogger └── socket.io-client@3.1.1

python-engineio==4.0.0
python-socketio==5.0.4
Flask==1.1.2
Flask-Session==0.3.2
Flask-SocketIO==5.0.1

How can I define JavaScript Socket.IO version and Socket.IO protocol revision so everything matches according to (https://pypi.org/project/python-socketio/) ?

How can I fix this? Thank you

There appears to be some backward compatibility issues with SocketIO. You can uninstall python-engineio, python-socketio (and Flask-SocketIO just to be on the safe side) and reinstall lower versions.

The combination that worked for me was:

Flask-SocketIO==4.3.1
python-engineio==3.13.2
python-socketio==4.6.0