Cloudflare IP update script

#!/bin/bash

CF_DEBUG=0
CF_TEMP_FILE="<OUTPUT LOG FILE>"

CF_API_TOKEN="<API KEY SCOPED TO UPDATE RECORDS>"
CF_ZONE_ID="<DNS ZONE / DOMAIN ID>"
CF_RECORD_ID="<DNS RECORD ID FOR A RECORD FROM CLOUDFLARE>"


if [ -e ${CF_TEMP_FILE} ]; then
  rm ${CF_TEMP_FILE}
fi

DATE=`date`
echo "=============================="
echo "Start update at ${DATE}"

CUR_EXT_IPV4=`wget -qO - ipv4.icanhazip.com`
if [ ${#CUR_EXT_IPV4} -gt 6 ]; then
  # A valid v4 IP address must be in the form X.X.X.X
  echo "Valid IP found: ${CUR_EXT_IPV4}"

  # See if we need to update
  CUR_IPV4_CHECK="\"content\":\"${CUR_EXT_IPV4}\""
  CURL_GET_REQUEST="$(curl -s -H "Authorization: Bearer ${CF_API_TOKEN}" -H "Content-Type: application/json" \
                          -X GET "https://api.cloudflare.com/client/v4/zones/${CF_ZONE_ID}/dns_records/${CF_RECORD_ID}")"

  if [[ $CURL_GET_REQUEST == *"$CUR_IPV4_CHECK"* ]]; then
    echo "No update neccessary; IP on Cloudflare already matches!"
  else
    echo "Updating Cloudflare..."

    # Proceed to update using curl
    CURL_UPDATE_REQUEST="$(curl -s --write-out "%{http_code}\n" --output ${CF_TEMP_FILE} -H "Authorization: Bearer ${CF_API_TOKEN}" -H "Content-Type: application/json" \
                            -d '{"type":"A","name":"trenzalore.ninearches.net","content":"'"${CUR_EXT_IPV4}"'"}' \
                            -X PUT "https://api.cloudflare.com/client/v4/zones/${CF_ZONE_ID}/dns_records/${CF_RECORD_ID}")"

    if [ $CURL_UPDATE_REQUEST -eq 200 ]; then
      echo "Update completed successfully."
    else
      echo "Update could not be completed: ${CURL_UPDATE_REQUEST}"
    fi

    if [ $CF_DEBUG -eq 1 ]; then
      cat ${CF_TEMP_FILE}
    fi

  fi
else
  echo "Could not get a valid IP."
fi

echo "End update at ${DATE}"
echo ""
echo ""

# End