- Python sockjs server setup $virtualenv testenv $source testenv/bin/activate $pip install twisted==15.0.0 txsockjs $python twisted-sockjs.py - Sockjs client setup $npm install $node server.js - Test Open http://localhost:9999 in a web browser(e.g. chrome), and input some message into the input box, and type Enter. The server will echo the message received. - In the python virtual environment, upgrade twisted (to 16.5.0 or 16.6.0), and restart the sockjs server $pip install twisted==16.5.0 $python twisted-sockjs.py - Problem Server can not receive the messages from the client, and can not echo the messages. - Conclusion The txsockjs package is not compatible with the latest twisted version, the server can send messages to the clients, but can not receive messages from the clients.