CoreOS Toolbox by DigitalOcean

toolbox.sh

#!/bin/bash

TOOLBOX_DOCKER_IMAGE=fedora
TOOLBOX_DOCKER_TAG=latest
TOOLBOX_USER=root

toolboxrc="${HOME}"/.toolboxrc

if [ -f "${toolboxrc}" ]; then
    source "${toolboxrc}"
fi

machinename=$(echo "${USER}-${TOOLBOX_DOCKER_IMAGE}-${TOOLBOX_DOCKER_TAG}" | sed -r 's/[^a-zA-Z0-9_.-]/_/g')
machinepath="/var/lib/toolbox/${machinename}"
osrelease="${machinepath}/etc/os-release"
if [ ! -f ${osrelease} ] || systemctl is-failed -q ${machinename} ; then
    sudo mkdir -p "${machinepath}"
    sudo chown ${USER}: "${machinepath}"

    docker pull "${TOOLBOX_DOCKER_IMAGE}:${TOOLBOX_DOCKER_TAG}"
    docker run --name=${machinename} "${TOOLBOX_DOCKER_IMAGE}:${TOOLBOX_DOCKER_TAG}" /bin/true
    docker export ${machinename} | sudo tar -x -C "${machinepath}" -f -
    docker rm ${machinename}
    sudo touch ${osrelease}
fi

sudo systemd-nspawn -D "${machinepath}" --share-system --bind=/:/media/root --bind=/usr:/media/root/usr --user="${TOOLBOX_USER}" "$@"