linode update dns with APIV4

linode-dns.sh

#!/bin/sh

TOKEN=""
DOMAIN_ID=""
RECORD_ID=""
WAN_IP=`curl -s ipecho.net/plain`;
OLD_WAN_IP=`cat /tmp/CURRENT_WAN_IP.txt`

func_go () {
  curl -H "Content-Type: application/json" \
  -H "Authorization: Bearer $TOKEN" \
  -X PUT -d "{
    \"name\": \"$SUB_NAME\",
    \"target\": \"$WAN_IP\"
  }" \
  "https://api.linode.com/v4/domains/$DOMAIN_ID/records/$RECORD_ID"
}

if [ "$WAN_IP" = "$OLD_WAN_IP" ]; then
  echo "IP Unchanged"
else
  echo $WAN_IP > /tmp/CURRENT_WAN_IP.txt
  func_go;
fi