# DynDNS Updater

A dynamic DNS updater service that automatically updates DNS records with your current IP address.

## Configuration (config.json)

The `config.json` file contains all settings for the updater. Here's a detailed explanation of each option:

### Root Level Options

#### `ip_lookup` (required)
Specifies the services used to discover your public IP addresses.

```json
"ip_lookup": {
  "ipv4": ["https://api.ipify.org", "..."],
  "ipv6": ["https://api6.ipify.org", "..."]
}
```

- **`ipv4`** (array of URLs): List of services to query for your IPv4 address. Services are tried in random order until one succeeds.
- **`ipv6`** (array of URLs): List of services to query for your IPv6 address. Services are tried in random order until one succeeds.

#### `domains` (required)
Dictionary containing the active domain configurations to update. Each key is a domain name, and each value is a domain configuration object (see below).

```json
"domains": {
  "example.com": { ... },
  "another.com": { ... }
}
```

#### `interval` (optional)
How frequently (in seconds) to check for IP changes and update domains. Defaults to `600` (10 minutes).

```json
"interval": 300
```

### Domain Configuration Format

Each entry in the `domains` dictionary has the following structure:

```json
"example.com": {
  "modes": ["ipv4", "ipv6"],
  "url": "https://api.example.com/update",
  "method": "GET",
  "params": {
    "token": "your-token",
    "domain": "${DOMAIN}",
    "ip": "${IPV4}"
  },
  "headers": {
    "Authorization": "Bearer token-value"
  }
}
```

#### Domain Options

- **`modes`** (array, optional): Which IP versions to update. Options are `"ipv4"` and/or `"ipv6"`. Defaults to `["ipv4"]`.

- **`url`** (string, required): The endpoint URL of your DNS service provider's update API.

- **`method`** (string, optional): HTTP method to use for the update request. Defaults to `"GET"`. Other options: `"POST"`, `"PUT"`, etc.

- **`params`** (object, optional): Query parameters (for GET/HEAD requests) or request body parameters to send with the update request. Supports variable substitution.

- **`headers`** (object, optional): HTTP headers to include in the request. Supports variable substitution. Use for authentication headers like `Authorization` or `X-API-Key`.

#### Variable Substitution

These variables are automatically replaced in `params` and `headers` values:

- `${DOMAIN}`: The domain name being updated
- `${IPV4}`: Your current IPv4 address
- `${IPV6}`: Your current IPv6 address

## Setup

1. Create or edit `config.json` with:
   - Configure `ip_lookup` with services to detect your public IPs
   - Add your domain configurations to the `domains` section
   - Replace placeholder values with your actual API tokens and credentials
   - Specify which IP versions to update in `modes` for each domain
   - (Optional) Adjust `interval` if needed

2. Run the updater to start keeping your DNS records current