DigitalOcean refresh domain data

do_ip.sh

#!/bin/bash
# Simple IP address update with DigitalOcean API
# https://gist.github.com/icetee/85739d374380d15ebfec271f41e8bfbe
#
# Run every 15 minutes? Use `crontab -e` and paste this
# */15 * * * * /home/pi/ip.sh >/dev/null 2>&1
# -----------------------------------------------------------------------------

# Variables
API="https://api.digitalocean.com/v2"
ID="__ID__"
TOKEN="__TOKEN__"
DOMAIN="__DOMAIN__"
MDNAME=".iphash"
IP1="https://l2.io/ip"
IP2="https://api.ipify.org"

# Logic
IP=$(curl -s $IP1)
if ! [[ $IP =~ ^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}$ ]]; then
    IP=$(curl -s $IP2)
fi

CURR_MD="$(echo $IP | md5sum | cut -d' ' -f1)"
FILE_MD="$(echo | cat $MDNAME | head -1 | cut -d' ' -f1)"

if [ "$CURR_MD" != "$FILE_MD" ]; then
    echo $IP | md5sum > "$MDNAME"

    DATA='{"id": "'$ID'", "data": "'$IP'"}'

    RESPONSE=$(curl -X PUT \
         -H "Content-Type: application/json" \
         -H "Authorization: Bearer $TOKEN" \
         -d "$DATA" \
         "$API/domains/$DOMAIN/records/$ID")
else
    exit;
fi