cannot access Lab directly (ignoring Spawner.default_url)

I tried to test jupyterhub + dockerspawner with JupyterLab .

I can access Lab page if I type the URL (such that /user/%U/lab) but I cannot access directly from Login Screen.

And I can access Lab directly when I don’t use dockerspawner.

There are no logs to GET /lab or /user/%U/lab on the logs of jupyterhub and docker container. I’m wondering if dockerspawner ignores or overwrites Spawner.default_url setting.

I use jupyterhub 0.6.1 (installed by conda) dockerspawner 0.5.0

The Dockerfile when I tried to build image is here.

FROM jupyterhub/singleuser:latest

USER root
RUN echo "dash dash/sh boolean false" | debconf-set-selections
RUN DEBIAN_FRONTEND=noninteractive dpkg-reconfigure dash
RUN apt-get update -y
RUN apt-get upgrade -y
RUN apt-get install -y htop
RUN conda update --all -c defaults --yes
RUN conda config --set channel_priority false
RUN conda install -c conda-forge jupyterlab --yes
RUN jupyter serverextension enable --py jupyterlab --sys-prefix

And extract from my jupyterhub_config.py is here.

c.JupyterHub.spawner_class = 'dockerspawner.DockerSpawner'
c.DockerSpawner.hub_ip_connect = '172.17.0.1'
c.JupyterHub.hub_ip = '172.17.0.1'
c.DockerSpawner.container_image = "oooooooooo"
c.Spawner.default_url = '/lab'

[harapekoaomushi]

@steverweber Great!! I can access /lab directly when the following parameters are set on Dockerfile equal to your recommended arguments. Thank you very much.

CMD ["sh", "/srv/singleuser/singleuser.sh", "--SingleUserNotebookApp.default_url=/lab", "--SingleUserNotebookApp.disable_user_config=True"]

[steverweber]

perhaps use

    --SingleUserNotebookApp.default_url=/lab \

like.
sudo -E -u $USER jupyterhub-singleuser \
    --debug \
    --port=8888 \
    --ip=0.0.0.0 \
    --user=$JPY_USER \
    --cookie-name=$JPY_COOKIE_NAME \
    --base-url=$JPY_BASE_URL \
    --hub-prefix=$JPY_HUB_PREFIX \
    --hub-api-url=$JPY_HUB_API_URL \
    --SingleUserNotebookApp.default_url=/lab \
    --SingleUserNotebookApp.disable_user_config=True \
...