Change cloudflare dns record for dynamic IP address

.dynamic-dns-cloudflare

Script to update dns record for dynamic ip

cloudflare-update-record.sh

#!/bin/bash
# Load env.txt
if [ -f env.txt ]; then
    export $(cat env.txt | xargs)
else
    echo "env.txt file not found"
    exit 0
fi

# Read from .env
auth_email=${AUTH_EMAIL}
auth_key=${DNS_EDIT_KEY}
zone_name=${ZONE_NAME}
record_name=${RECORD_NAME}

# MAYBE CHANGE THESE
ip=$(curl -s http://ipv4.icanhazip.com)
ip_file="ip.txt"
log_file="log.txt"

# LOGGER
log() {
    if [ "$1" ]; then
        echo -e "[$(date)] - $1" >> $log_file
    fi
}

# SCRIPT START
log "Check Initiated"

if [ -f $ip_file ]; then
    old_ip=$(cat $ip_file)
    if [ $ip == $old_ip ]; then
        log "IP has not changed."
        echo "IP has not changed."
        exit 0
    fi
fi

zone_identifier=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones?name=$zone_name" -H "X-Auth-Email: $auth_email" -H "Authorization: Bearer $auth_key" -H "Content-Type: application/json" | grep -Po '(?<="id":")[^"]*' | head -1 )
record_identifier=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones/$zone_identifier/dns_records?name=$record_name" -H "X-Auth-Email: $auth_email" -H "Authorization: Bearer $auth_key" -H "Content-Type: application/json"  | grep -Po '(?<="id":")[^"]*')
update=$(curl -s -X PUT "https://api.cloudflare.com/client/v4/zones/$zone_identifier/dns_records/$record_identifier" -H "X-Auth-Email: $auth_email" -H "Authorization: Bearer $auth_key" -H "Content-Type: application/json" --data "{\"id\":\"$zone_identifier\",\"type\":\"A\",\"name\":\"$record_name\",\"content\":\"$ip\"}")

if [[ $update == *"\"success\":true"* ]]; then
    message="IP changed to: $ip"
    echo "$ip" > $ip_file
    log "$message"
    echo "$message"
else
    message="API UPDATE FAILED. DUMPING RESULTS:\n$update"
    log "$message"
    echo "$message"
fi

env.txt

AUTH_EMAIL=cloudflare_email  
DNS_EDIT_KEY=cloudflare_zone_dns_edit_key  
ZONE_NAME=sample.com
RECORD_NAME=.sample.com