Jupyterhub can not download large file(>100MB) with download button

Hello!

Apparently, the problem is in the web server limitation ‘tornado>=6.2’. To bypass the 100 megabyte limit, you can change the line in the iostream.py file (located in the virtual environment libraries)

can be found via:

find your_virtual_environment/ | grep ‘tornado/iostream.py’

The line found:
self.max_buffer_size = max_buffer_size or 104857600

we will change it to:
self.max_buffer_size = 1073741824 #1Gb

So, after changing the value in the iostream.py file and restarting the jupyterhub service, I started downloading files up to 1 gigabyte in size normally.

I hope this will help someone else too.

PS, I did not find how to change this value via jupyterhub_config.py, perhaps in new versions this is not available at all.