#!/usr/bin/env sh echo "certbot txt record: $CERTBOT_VALIDATION" >&2 baseurl='https://www.duckdns.org/update?domains=%s&token=%s&txt=%s' result="$(printf "url=$baseurl\n" "$DUCKDNS_DOMAIN" "$DUCKDNS_TOKEN" "$CERTBOT_VALIDATION" | curl -K -)" # give some time for the record to update echo "waiting for txt record" >&2 for i in $(seq 0 60); do val="$(nslookup -type=TXT "$DUCKDNS_DOMAIN.duckdns.org" | grep "$DUCKDNS_DOMAIN.duckdns.org.*text.*=.*" | sed -n 's/.*"\([^"]*\)".*/\1/p')" echo "$val" >&2 test "$val" = "$CERTBOT_VALIDATION" && break sleep 10 done test "$result" = 'OK'