Route 53 record updater

What?

This is a small Go tool that updates an AWS Route53 A record with a dynamic public IP address.

The process has two stages:

1. Resolve the current public IP address

The tool expects an external HTTP endpoint that accepts a GET request and returns JSON in either of these forms:

{
  "ip": "127.0.0.1"
}

or:

{
  "ip_address": "127.0.0.1"
}

An example implementation of such a service can be found here.

2. Update Route53

Once the public IP is resolved, the tool sends an UPSERT request to Route53 for the configured A record.

Configuration

Configuration is provided through environment variables. If any required variable is missing, the process exits with an error.

• RESOLVER_URL: URL of the IP resolver endpoint.
• API_KEY: API key sent as the x-api-key request header.
• HOSTED_ZONE_ID: Route53 hosted zone ID.
• RECORD_SET: FQDN of the record to update.

Logging

The application logs extensively to STDOUT with UTC timestamps, including:

• startup and configuration loading (without printing secrets),
• resolver request/response metadata and IP parsing,
• Route53 client initialization and UPSERT submission,
• success/failure status and error context.

Usage

RESOLVER_URL='<AN_URL>' \
API_KEY='<AN_API_KEY>' \
HOSTED_ZONE_ID='<YOUR_ZONE_ID>' \
RECORD_SET='<YOUR_RECORD_SET>' \
go run ./main.go

Example

RESOLVER_URL='https://resolver.example.org/whatsmyip' \
API_KEY='123456' \
HOSTED_ZONE_ID='FOO' \
RECORD_SET='dynamic.example.org' \
go run ./main.go