⚠️ ui.upload File upload stops at 99.9%

[adarshpunj]

Description

I checked a previous issue related to this which was closed. However, I'm still facing this issue.

Interestingly, it's working normally on my Mac. Though, it stops at 99.9% on a Linux VM. Note that I'm using Docker image in both cases.

Version - 1.4.22

I'm able to reproduce this on both Firefox on Chrome.

I didn't encounter this issue with file size < 1 MB. I tested two files 5 MB and 29 MB, where the upload fails (or passes) at 99.9%

Attaching my code if that helps:

ui.upload(
       on_upload=lambda e: self.fn(e=e),
       label="",
       auto_upload=True,
       multiple=False,
    ).props("accept=.csv")

The function self.fn

def _handle_file_upload(e: events.UploadEventArguments):
    file = e.content
    global df
    df = pd.read_csv(filepath_or_buffer=file, encoding="latin")

    _table.refresh(...)

[falkoschindler]

Thanks, @adarshpunj!

So I assume we can boil it down to this reproduction:

ui.upload(on_upload=lambda e: ui.notify(f'{len(e.content.read())} bytes'), auto_upload=True)

Unfortunately I can't reproduce it on my Mac. Can anyone else help?

[adarshpunj]

@falkoschindler - The culprit here is nginx.

So whenever you upload a file bigger than 1 MB (which is max limit for nginx by default), nginx doesn't allow it on the server and NiceGUI hangs at 99.9%.

I was able to solve it by changing the client_max_body_size in nginx config.

I believe this can be troublesome in production environments, hence an error message from NiceGUI end will be helpful.

[falkoschindler]

Oh wow, thanks for the update, @adarshpunj!
Do you have an idea how NiceGUI could check for this limitation? We'd love to show a warning or error message, but I'm not sure how to trigger it.

[adarshpunj]

Sure, I'm looking into it, will update once I have some info.