The Littlest JupyterHub: Share data with existing users

tljh-share-data.sh

#!/bin/bash

# The official tutorial describes how to create shared folders for new users:
# https://tljh.jupyter.org/en/latest/howto/content/share-data.html

# But it still doesn't reflect how to propagate any new shared folders to existing users.
# This script features an example for the missing task.

if [[ $(id -u) -ne 0 ]]
then
        echo "Please run me as root again..."
        exit 1
fi

# Shared folder names:
INBOX=Inbox
OUTBOX=Outbox

# Shared folder permissions:
# INBOX  -> teacher (w) students (r)
# OUTBOX -> teacher (r) students (w)

create() {
  # Creates shared folders and sets desired permissions

  mkdir -vp /srv/data/${INBOX}
  mkdir -vp /srv/data/${OUTBOX}

  chown -v root:jupyterhub-admins /srv/data/${INBOX}
  chown -v root:jupyterhub-users /srv/data/${OUTBOX}

  chmod -v u=rwx,g=rwxs,o=rx /srv/data/${INBOX}
  chmod -v u=rwx,g=rwxs,o=rx /srv/data/${OUTBOX}

  rm -vrf /etc/skel/${INBOX}
  rm -vrf /etc/skel/${OUTBOX}

  ln -vs /srv/data/${INBOX} /etc/skel/${INBOX}
  ln -vs /srv/data/${OUTBOX} /etc/skel/${OUTBOX}
}

link() {
  # Links shared folders in existing user account

  USER=$(basename "${1}")

  rm -vrf /home/${USER}/${INBOX}
  rm -vrf /home/${USER}/${OUTBOX}

  su - ${USER} -c "ln -vs /srv/data/${INBOX} /home/${USER}/${INBOX}"
  su - ${USER} -c "ln -vs /srv/data/${OUTBOX} /home/${USER}/${OUTBOX}"
}

create

find /home -type d -name 'jupyter-*' -prune | while read USER
do
  echo
  link ${USER}
done