Create Swap on Raspberry Pi (Nodejs)

create_swap.sh

#!/bin/bash

# Check if root
if [[ $EUID -ne 0 ]]; then
   echo "This script must be run as root" 
   exit 1
fi

# Check if dphys-swapfile installed. If not, install it
if ! dpkg --get-selections | grep -q "^dphys-swapfile\(:.*\)\?[[:space:]]*install$" >/dev/null; then
  apt-get install dphys-swapfile -y
fi

# https://stackoverflow.com/questions/26193654/node-js-catch-enomem-error-thrown-after-spawn
script_file="$(cat<<'EOF'

MNT_POINT=/media/storage/
UUID=$(blkid | grep ZoneMinder | sed -n 's/.*UUID="\(.*\)".*/\1/p')
BLOCK_DEV=$(blkid | grep ZoneMinder | awk '{print $1}' | awk -F: '{print $1}')

if ! test -z "$UUID"; then
  if ! test -e $MNT_POINT; then
    mkdir -p $MNT_POINT
  fi

  if mount $BLOCK_DEV $MNT_POINT > /dev/null 2>&1; then
    dphys-swapfile swapon
  fi
fi
EOF
)"

nl=$'\n'
bsnl=$'\\\n'
parsed_script=${script_file//\\/\\\\}
packaged_script=${parsed_script//$nl/$bsnl}

# Prepend script to rc.local
sed -i '/^exit 0$/i'"$packaged_script" /etc/rc.local

# Modify /etc/dphys-swapfile config file
if ! grep "^CONF_SWAPFILE=" /etc/dphys-swapfile > /dev/null 2>&1; then 
  echo -e "CONF_SWAPFILE=/media/storage/swapfile\nCONF_MAXSWAP=2048" | tee -a /etc/dphys-swapfile
fi

# Execute script
sh /etc/rc.local