docker-shell

#!/bin/sh
#
# Copyright (c) 2017 Gaël PORTAY <gael.portay@savoirfairelinux.com>
#
# This program is free software: you can redistribute it and/or modify it under
# the terms of the MIT License.
#

set -e

usage() {
	cat <<EOF
Usage: ${0##*/} [OPTIONS] [--] [COMMAND] [ARG...]
       ${0##*/} [OPTIONS]  -c   COMMAND  [ARG...]

Run a shell as user in a new container and bind mount cwd

Options:
      --help                    Print usage
EOF
}

docker_build() {
	cat "$1" - <<EOF | docker build --tag "$2" -
RUN groupadd --non-unique --gid $GROUPS $USER
RUN useradd  --non-unique --gid $GROUPS --uid $UID --create-home --home-dir /home/$USER --shell $SHELL $USER
EOF
}

opts="--rm --volume $PWD:/home/$USER"
while [ "$#" -ne 0 ]; do
	if [ "$1" = "-h" ] || [ "$1" = "--help" ]; then
		usage
		exit 0
	elif [ "$1" = "-c" ] || [ "$1" = "--" ]; then
		shift
		break
	else
		break
	fi
	shift

done

hash="$(realpath "Dockerfile" | sha256sum - | cut -d' ' -f1)"
tag="dsh-$hash"
docker_build "Dockerfile" "$tag" >&2

if [ "$#" -eq 0 ]; then
	opts+=" --tty"
	opts+=" --interactive"
	set -- su -l $USER
else
	set -- su -l $USER -c "$*"
fi

exec docker run $opts "$tag" "$@"