Whether the preferred-dir parameter can accept relative paths

[xuoutput]

Problem

➜   jupyter --version
Selected Jupyter core packages...
IPython          : 7.30.1
ipykernel        : 5.5.5
ipywidgets       : not installed
jupyter_client   : 7.1.0
jupyter_core     : 4.9.1
jupyter_server   : 1.13.1
jupyterlab       : 3.2.5
nbclient         : 0.5.9
nbconvert        : 6.3.0
nbformat         : 5.1.3
notebook         : 6.4.6
qtconsole        : not installed
traitlets        : 5.1.1

tree /home

/home/
├── other_user
│   └── hi.txt
└── user
    └── getting_started.ipynb

When I do not start jupyterlab in the /home path

jupyter lab --notebook-dir='/home' --preferred-dir='other_user'
# or
jupyter lab --notebook-dir='/home' --preferred-dir='./other_user'

[C 2021-12-22 22:16:22.818 ServerApp] Bad config encountered during initialization: No such preferred dir: ''/other_user''
# or
[C 2021-12-22 22:11:45.671 ServerApp] Bad config encountered during initialization: preferred_dir must be equal or a subdir of root_dir: ''/user''

When I start jupyterlab in the /home path, it is normal

solution

➜   jupyter lab  --notebook-dir='/home' --preferred-dir='/home/other_user'

Proposed Solution

Whether the preferred-dir parameter can accept relative paths

Additional context

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[krassowski]

Hi @xuoutput I think that this was fixed in https://github.com/jupyterlab/jupyterlab_server/pull/233. You can test it after upgrading to latest jupyterlab_server with pip install -U jupyterlab-server (or conda/mamba equivalent).