#!/usr/bin/env bash # vim: set filetype=sh set -euo pipefail api_host="https://api.digitalocean.com/v2" sleep_interval=${SLEEP_INTERVAL:-300} remove_duplicates=${REMOVE_DUPLICATES:-"false"} # Only services with ipv6 supported are listed here. # And are not using cloudflare or similar services # that may block requests from this script. services=( "ifconfig.io" ) info() { echo "$1" >/dev/stdout } warn() { echo "$1" >/dev/stderr } error() { warn "$1" exit 1 } test -f "${DIGITALOCEAN_TOKEN_FILE:-}" && DIGITALOCEAN_TOKEN="$(cat "$DIGITALOCEAN_TOKEN_FILE")" test -z "$DIGITALOCEAN_TOKEN" && error "DIGITALOCEAN_TOKEN not set!" test -z "${DOMAIN}" && error "DOMAIN not set!" test -z "${NAME}" && error "NAME not set!" dns_list="$api_host/domains/$DOMAIN/records" configure_record() { # disable glob expansion set -f ip=$1 type=$2 for sub in ${NAME//;/ }; do record_id=$(echo "$domain_records" | jq ".domain_records[] | select(.type == \"$type\" and .name == \"$sub\") | .id") record_data=$(echo "$domain_records" | jq -r ".domain_records[] | select(.type == \"$type\" and .name == \"$sub\") | .data") if [ "$(echo "$record_id" | wc -l)" -ge 2 ]; then if [[ "${remove_duplicates}" == "true" ]]; then echo "'$sub' domain name has duplicate DNS records, removing duplicates" record_id_to_delete=$(echo "$record_id" | tail -n +2) record_id=$(echo "$record_id" | head -1) record_data=$(echo "$record_data" | head -1) while IFS= read -r line; do curl -s -X DELETE \ -H "Content-Type: application/json" \ -H "Authorization: Bearer $DIGITALOCEAN_TOKEN" \ "$dns_list/$line" &>/dev/null done <<<"$record_id_to_delete" else warn "Unable to update '$sub' domain name as it has duplicate DNS records. Set REMOVE_DUPLICATES='true' to remove them." continue fi fi # re-enable glob expansion set +f data="{\"type\": \"$type\", \"name\": \"$sub\", \"data\": \"$ip\"}" url="$dns_list/$record_id" if [[ -z $record_id ]]; then info "No record found with '$sub' domain name. Creating record, sending data=$data to url=$url" new_record=$(curl -s -X POST \ -H "Content-Type: application/json" \ -H "Authorization: Bearer $DIGITALOCEAN_TOKEN" \ -d "$data" \ "$url") record_data=$(echo "$new_record" | jq -r ".data") fi if [[ "$ip" != "$record_data" ]]; then info "existing DNS record address ($record_data) doesn't match current IP ($ip), sending data=$data to url=$url" curl -s -X PUT \ -H "Content-Type: application/json" \ -H "Authorization: Bearer $DIGITALOCEAN_TOKEN" \ -d "$data" \ "$url" &>/dev/null else info "existing DNS record address ($record_data) did not need updating" fi done } while (true); do domain_records=$(curl -s -X GET \ -H "Content-Type: application/json" \ -H "Authorization: Bearer $DIGITALOCEAN_TOKEN" \ "$dns_list?per_page=200") for service in "${services[@]}"; do info "Trying with $service..." ipv4="$(curl -4 -s -f --connect-timeout 2 "$service" || echo "")" ipv6="$(curl -6 -s -f --connect-timeout 2 "$service" || echo "")" if [[ -n "$ipv4$ipv6" ]]; then break else warn "Failed to retrieve IP from $service" fi done if [[ -z $ipv4 ]]; then warn "IPv4 wasn't retrieved within allowed interval. Will try $sleep_interval seconds later.." else info "Found IPv4 address $ipv4" configure_record "$ipv4" "A" fi if [[ -z $ipv6 ]]; then warn "IPv6 wasn't retrieved within allowed interval. Will try $sleep_interval seconds later.." else info "Found IPv6 address $ipv6" configure_record "$ipv6" "AAAA" fi sleep "$sleep_interval" done