Task runner with real time progress messages - figuring it all out

[dirkroorda]

How to let the webserver start a shell command in the background and collect the output in real time and let the user kill such a process?

This should be doable in Flask-SocketIO, and it is, but it takes a fair amount of research.

These things are far from trivial:

1. if you let flask-socketio spawn shell command in the background with pythons subprocess module, how can I collect the output in real time without blocking?
2. how can I collect both stderr and stdin in real time?
3. how can I kill such a task from the controlling website?

I put the answers, plus a working example in this repo.

[miguelgrinberg]

Nice! Thank you so much for sharing it. This is indeed a common request, and I never got around to creating a working example.