prepare-vps.sh

#!/bin/bash

# Make sure only root can run our script
if [[ "$(id -u)" -ne 0 ]]
 then
   echo "This script must be run as root" 1>&2
   exit 1
fi

upgrade()
{
  echo -n "Upgrade the system? (y/N) "
  read -r touche </dev/tty
  if [[ "$touche" = "y" || "$touche" = "o" ]]
   then
    apt-get update && apt-get -y upgrade
  fi
}

timezone()
{
  echo -n "Update timezone? (y/N) "
  read -r touche </dev/tty
  if [[ "$touche" = "y" || "$touche" = "o" ]]
  then
    apt-get install ntp ntpdate </dev/tty
    if dpkg -l tzdata; then
      apt-get install -y tzdata
    else
      dpkg-reconfigure tzdata
    fi
  fi
}

password()
{
  echo -n "Define / change the root password (usefull for recovery mode)? (y/N) "
  read -r touche </dev/tty
  if [[ "$touche" = "y" || "$touche" = "o" ]]
  then
    passwd </dev/tty
  fi
}

force_rsa()
{
  echo -n "Disable root login using password? (only rsa key) (y/N) "
  read -r touche </dev/tty
  if [[ "$touche" = "y" || "$touche" = "o" ]]
  then
    sed -i 's/#PasswordAuthentication yes/PasswordAuthentication no/g' /etc/ssh/sshd_config
    /etc/init.d/ssh restart
  fi
}

add_swap()
{
  free -h
  echo -n "Add swap? (highly recommended) (y/N) "
  read -r touche </dev/tty
  if [[ "$touche" = "y" || "$touche" = "o" ]]
  then
    read -rp "What's the size (in GB)? Please input a number between 1 and 4: " swap_value </dev/tty
    echo "creating ${swap_value}G swap file"
    fallocate -l "${swap_value}G" /swapfile
    chmod 600 /swapfile
    mkswap /swapfile
    swapon /swapfile
    echo '/swapfile none swap sw 0 0' | tee -a /etc/fstab
    echo 'vm.swappiness = 10' >> /etc/sysctl.conf
    echo 'vm.vfs_cache_pressure=50' >> /etc/sysctl.conf
  fi
}

mount_vol()
{
  echo -n "Mount a volume (like /dev/vdx)? (y/N) "
  read -r touche </dev/tty
  if [[ "$touche" = "y" || "$touche" = "o" ]]
  then
    fdisk -l
    read -rp "Specify volume name (eg. vdb): " volume_name </dev/tty
    read -rp "Specify destination path (eg. /apps): " path_name < /dev/tty
    read -rp "Do you really want to format and mount the volume /dev/${volume_name} on ${path_name} ? (y/n) : " touche </dev/tty
    if [[ "$touche" = "y" || "$touche" = "o" ]]
    then
      mkfs -t ext4 "/dev/${volume_name}"
      mkdir -p ${path_name}
      mount "/dev/${volume_name}" ${path_name}
      uuid_value=$(blkid -o value -s UUID /dev/${volume_name})
      echo "UUID=\"${uuid_value}\" ${path_name} ext4 defaults,nofail 0 2" >> /etc/fstab
    fi
  fi
}

install_docker()
{
  echo -n "Install Docker from docker-ce repository? (y/N) "
  read -r touche </dev/tty
  if [[ "$touche" = "y" || "$touche" = "o" ]]
  then
    apt-get install --yes apt-transport-https ca-certificates curl gnupg lsb-release
    local os=$(lsb_release -is | tr "[:upper:]" "[:lower:]")
    curl -fsSL "https://download.docker.com/linux/$os/gpg" | gpg --dearmor -o /usr/share/keyrings/docker-archive-keyring.gpg
    echo \
      "deb [arch=$(dpkg --print-architecture) signed-by=/usr/share/keyrings/docker-archive-keyring.gpg] https://download.docker.com/linux/$os \
      $(lsb_release -cs) stable" | tee /etc/apt/sources.list.d/docker.list > /dev/null
    apt update
    apt-cache policy docker-ce
    apt-get install --yes docker-ce docker-ce-cli containerd.io
    systemctl status docker
  fi
}

install_docker_compose()
{
  echo -n "Install Docker Compose from docker-ce repository? (y/N) "
  read -r touche </dev/tty
  if [[ "$touche" = "y" || "$touche" = "o" ]]
  then
    apt-get install --yes docker-compose-plugin bash-completion
    docker compose version
  fi
}

function trap_ctrlc()
{
  echo "Ctrl^C, exiting..."
  exit 2
}


vps_prepare()
{
  trap "trap_ctrlc" 2 # SIGINT
  upgrade
  timezone
  password
  force_rsa
  add_swap
  mount_vol
  install_docker
  install_docker_compose
}

vps_prepare "$@"