initial commit

Dockerfile

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+FROM alpine
+MAINTAINER Alper Kanat <tunix@raptiye.org>
+RUN apk --no-cache add curl jq
+COPY dyndns.sh /
+ENTRYPOINT exec /dyndns.sh

README.md

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+# Dynamic DNS using DigitalOcean's DNS Services

dyndns.sh

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+#!/bin/sh
+
+api_host="https://api.digitalocean.com/v2"
+sleep_interval=${SLEEP_INTERVAL:-300}
+
+die() {
+    echo "$1"
+    exit 1
+}
+
+test -z $DIGITALOCEAN_TOKEN && die "DIGITALOCEAN_TOKEN not set!"
+test -z $DOMAIN && die "DOMAIN not set!"
+test -z $NAME && die "NAME not set!"
+
+dns_list="$api_host/domains/$DOMAIN/records"
+domain_records=$(curl -s -X GET \
+    -H "Content-Type: application/json" \
+    -H "Authorization: Bearer $DIGITALOCEAN_TOKEN" \
+    $dns_list)
+record_id=$(echo $domain_records| jq ".domain_records[] | select(.name == \"$NAME\") | .id")
+
+test -z $record_id && die "No record found with given domain name!"
+
+while ( true ); do
+    ip="$(curl -s ipinfo.io/ip)"
+    data="{\"type\": \"A\", \"name\": \"$NAME\", \"data\": \"$ip\"}"
+    url="$dns_list/$record_id"
+
+    if [[ -n $ip ]]; then
+        echo "Sending data=$data to url=$url"
+
+        curl -s -X PUT \
+            -H "Content-Type: application/json" \
+            -H "Authorization: Bearer $DIGITALOCEAN_TOKEN" \
+            -d "$data" \
+            "$url" &> /dev/null
+    else
+        echo "IP wasn't retrieved within allowed interval. Will try $sleep_interval seconds later.."
+    fi
+
+    sleep $sleep_interval
+done