I’m a very new Dash user.
I’d working on an etude that uploads files and displays a table of the results.
I’m cribbing/stealing blatantly from the Dash upload docs and other example (e.g. from docs.faculty.ai). The full source is over here at this gist.
It works, but every once in a while when I upload something I’ll get a pop-up in the browser window that says “Failed to fetch”, e.g.
I’m also seeing this in the console:
I’m running the app as python upload.py
and the invoking the app object in upload.py
like so:
app.run_server(debug=True, port=8888, host="172.16.193.97")
I can’t figure out a pattern, it doesn’t seem to be related to size or name or … It’s more likely to happen when I upload multiple files, but not necessarily. Also seems more like just after the page is refreshed.
Perhaps I need to be running multiple processes in the backend, or checking some status/ready flag?
While I’d love to figure out what’s going on, I’d also love to learn more about how to debug these types of errors?
- What does this error actually mean?
- Is there a way to dig into it from either the browser or backend?
- Is there a Debugging manual somewhere that I’ve overlooked?
- Often when I get errors they end up cascading and rolling off the top of the screen, particularly if I’ve killed the server. Is there a way to stop the event loop [SIC] that’s firing in the browser?