feat: dynamic DNS updater sidecar (auto-updates A + AAAA every 5min)

- update-dns.sh: detects public IPv4/IPv6, upserts CF records
- Runs on container start + every 5 minutes
- Only updates if IP actually changed (skips if unchanged)
- python:3-alpine container with curl

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

warzone/deploy/docker/update-dns.sh

@@ -0,0 +1,98 @@
+#!/bin/sh
+# Updates voip.manko.yoga DNS records with current public IPs.
+# Runs once on startup, then every 5 minutes.
+# Reads CF token from /run/secrets/cf_api_token or CF_API_TOKEN env.
+
+DOMAIN="voip.manko.yoga"
+ZONE="manko.yoga"
+INTERVAL="${DNS_UPDATE_INTERVAL:-300}"
+
+get_token() {
+  if [ -f /run/secrets/cf_api_token ]; then
+    cat /run/secrets/cf_api_token | tr -d '\n'
+  else
+    echo "$CF_API_TOKEN"
+  fi
+}
+
+get_zone_id() {
+  curl -s "https://api.cloudflare.com/client/v4/zones?name=$ZONE" \
+    -H "Authorization: Bearer $(get_token)" | \
+    python3 -c "import sys,json; print(json.load(sys.stdin)['result'][0]['id'])" 2>/dev/null
+}
+
+get_public_ipv4() {
+  curl -4 -s --connect-timeout 5 https://api.ipify.org 2>/dev/null || \
+  curl -4 -s --connect-timeout 5 https://ifconfig.me 2>/dev/null
+}
+
+get_public_ipv6() {
+  curl -6 -s --connect-timeout 5 https://api6.ipify.org 2>/dev/null || \
+  curl -6 -s --connect-timeout 5 https://ifconfig.co 2>/dev/null
+}
+
+upsert_record() {
+  local zone_id="$1" type="$2" content="$3" token
+  token=$(get_token)
+
+  # Check existing
+  local existing
+  existing=$(curl -s "https://api.cloudflare.com/client/v4/zones/$zone_id/dns_records?name=$DOMAIN&type=$type" \
+    -H "Authorization: Bearer $token")
+
+  local rec_id current
+  rec_id=$(echo "$existing" | python3 -c "import sys,json; r=json.load(sys.stdin)['result']; print(r[0]['id'] if r else '')" 2>/dev/null)
+  current=$(echo "$existing" | python3 -c "import sys,json; r=json.load(sys.stdin)['result']; print(r[0]['content'] if r else '')" 2>/dev/null)
+
+  if [ "$current" = "$content" ]; then
+    echo "  $type: $content (unchanged)"
+    return
+  fi
+
+  if [ -n "$rec_id" ]; then
+    curl -s -X PUT "https://api.cloudflare.com/client/v4/zones/$zone_id/dns_records/$rec_id" \
+      -H "Authorization: Bearer $token" \
+      -H "Content-Type: application/json" \
+      --data "{\"type\":\"$type\",\"name\":\"$DOMAIN\",\"content\":\"$content\",\"ttl\":120,\"proxied\":false}" > /dev/null
+    echo "  $type: $current -> $content (updated)"
+  else
+    curl -s -X POST "https://api.cloudflare.com/client/v4/zones/$zone_id/dns_records" \
+      -H "Authorization: Bearer $token" \
+      -H "Content-Type: application/json" \
+      --data "{\"type\":\"$type\",\"name\":\"$DOMAIN\",\"content\":\"$content\",\"ttl\":120,\"proxied\":false}" > /dev/null
+    echo "  $type: $content (created)"
+  fi
+}
+
+update() {
+  echo "[$(date -u +%H:%M:%S)] Checking DNS for $DOMAIN..."
+  local zone_id
+  zone_id=$(get_zone_id)
+  if [ -z "$zone_id" ]; then
+    echo "  ERROR: cannot get zone ID"
+    return
+  fi
+
+  local ipv4 ipv6
+  ipv4=$(get_public_ipv4)
+  ipv6=$(get_public_ipv6)
+
+  if [ -n "$ipv4" ]; then
+    upsert_record "$zone_id" "A" "$ipv4"
+  else
+    echo "  A: no IPv4 detected"
+  fi
+
+  if [ -n "$ipv6" ]; then
+    upsert_record "$zone_id" "AAAA" "$ipv6"
+  else
+    echo "  AAAA: no IPv6 detected"
+  fi
+}
+
+# Run immediately, then loop
+update
+while true; do
+  sleep "$INTERVAL"
+  update
+done