Script to create system users to run docker apps

create-docker-user.sh

#!/usr/bin/env bash

set -e

# create system users to be run docker apps
# put this file in your /sbin dir and chmod +x it

# this script:
# - create users without pass
# - and them to the docker group
# - generate key and print public key (to be used as deploy key)

die () {
    echo >&2 "$@"
    exit 1
}

[ "$#" -eq 1 ] || die "1 argument required, $# provided"

adduser --disabled-password --gecos "" $1
usermod -G docker $1

sudo \
  --set-home \
  -u $1 \
  bash -c 'ssh-keygen -t rsa -b 4096 -q -N "" -f ~/.ssh/id_rsa -C "$(whoami)@$(hostname)"'

sudo \
  --set-home \
  -u $1 \
  bash -c 'cat ~/.ssh/id_rsa.pub'

echo -e "\nuser '$1' created."