If you want to share a volume with Jupyterlab, this is unfortunately not enough. Each user gets their own Jupyterlab container from a notebook image. By default, this is jupyter/datascience-notebook. However, no media group is created in this container. There is also no user cloudron.
Since I created my own image, I could simply create the group media and add the user Jovyan. Now it works.

Great! Thanks a lot @girish

@balticpenguin this one https://docs.cloudron.io/apps/#log-viewer

Great, thanks @girish, it's working now.

Sounds interesting - from the article:

Later I will create an article where you can use any kind of PDF files

You can test the image like this:

root@my:~# docker run -ti joamatab/gdsfactory:latest /bin/bash (base) jovyan@9b8a75ecc913:~$ jupyterhub-singleuser --ip=0.0.0.0 Traceback (most recent call last): File "/opt/conda/bin/jupyterhub-singleuser", line 7, in <module> from jupyterhub.singleuser import main File "/opt/conda/lib/python3.8/site-packages/jupyterhub/singleuser/__init__.py", line 5, in <module> from .app import main File "/opt/conda/lib/python3.8/site-packages/jupyterhub/singleuser/app.py", line 10, in <module> from .mixins import make_singleuser_app File "/opt/conda/lib/python3.8/site-packages/jupyterhub/singleuser/mixins.py", line 22, in <module> from jinja2 import ChoiceLoader File "/opt/conda/lib/python3.8/site-packages/jinja2/__init__.py", line 12, in <module> from .environment import Environment File "/opt/conda/lib/python3.8/site-packages/jinja2/environment.py", line 25, in <module> from .defaults import BLOCK_END_STRING File "/opt/conda/lib/python3.8/site-packages/jinja2/defaults.py", line 3, in <module> from .filters import FILTERS as DEFAULT_FILTERS # noqa: F401 File "/opt/conda/lib/python3.8/site-packages/jinja2/filters.py", line 13, in <module> from markupsafe import soft_unicode ImportError: cannot import name 'soft_unicode' from 'markupsafe' (/opt/conda/lib/python3.8/site-packages/markupsafe/__init__.py)

Adding the following to /app/data/customconfig.py worked for me:

c.Spawner.args = ['--collaborative']

You also need to run /app/code/remove_notebook_containers.py after making changes.

For a list of parameters check out: https://jupyterhub.readthedocs.io/en/stable/api/spawner.html

@girish said in Installing JupyterHub extensions:

@infogulch OK, I tried this quickly now and it looks like 1GB is not enough for those webpack builds. I just put it to 4GB and that worked out. Maybe 2GB will suffice too...

I tried several different memory settings. In my use case 4G was the minimum needed for rebuilding.

@girish Thanks for the answer. Having one and only one environment per user is quite the inconvenience 😞