domain-watcher

A simple HTTP daemon that watches WHOIS/RDAP responses for domains. Every response is parsed and stored. It can be used to track domains that have expired or are close to expiring.

It is intended to be used with CLI HTTP clients such as cURL on Linux or Invoke-RestMethod in Windows PowerShell. It also includes a browser UI.

The daemon is built in C# with AOT compilation. The UI is written in solidjs and compiled to a single .html file.

Features

• automatic resolution of the WHOIS/RDAP server for a given TLD

• automatic WHOIS/RDAP queries for watched domains

• generation of a watched-domain list sorted by availability, then by expiration timestamp

• daemon API designed for cURL/PowerShell as the preferred control interface

• simple single .html file UI written in solidjs

• every raw response is stored in a sqlite db for further processing

• AOT compilation: no ORM - raw System.Data is used to support AOT compilation, with a custom HTTP server written from scratch

Instruction

Docker

To build the docker container, use docker build https://github.com/malciin/domain-watcher.git -t domain-watcher:1.0

Then run docker run --rm -it -p XYZ:80 -v domain-watcher.db:/app/sqlite.db domain-watcher:1.0, where XYZ is the port number.

Starting daemon

Run ./DomainsWatcher.Cli --port XYZ, where XYZ is the port number.

If you do not want to provide --port XYZ every time, create a settings.yaml file. Check settings.Reference.yaml to see the available options.

Usage CLI examples

(assume port to be 8051)

PowerShell	cURL	Description
Invoke-RestMethod http://localhost:8051	curl localhost:8051	Gets watched domain statuses
Invoke-RestMethod http://localhost:8051/google.com	curl localhost:8051/google.com	Gets the RDAP/WHOIS response for a domain. If a recent response is available, it returns the cached one. It does not change the domain's watch status
Invoke-RestMethod http://localhost:8051/google.com/f	curl localhost:8051/google.com/f	Gets a fresh RDAP/WHOIS response for any domain. It does not change the domain's watch status
Invoke-RestMethod http://localhost:8051 -Method 'POST' -Body 'google.com'	curl -d "google.com" localhost:8051	Watches a domain and returns its status
Invoke-RestMethod http://localhost:8051 -Method 'DELETE' -Body 'google.com'	curl -X DELETE -d "google.com" localhost:8051	Stops watching a domain
Invoke-RestMethod http://localhost:8051/queue	curl localhost:8051/queue	Gets the watched-domain queue status, including when each watched domain will be queried
Invoke-RestMethod http://localhost:8051/s/*.dev	curl localhost:8051/s/*.dev	Search endpoint. Returns the status of watched domains matching the given filter. In this example, it returns all watched domains for the .dev TLD. More information is available in the Searching section

Examples:

# Example usage
~$ curl localhost:8051
| Domain                  | Status    | Expiration | Queried    |
-----------------------------------------------------------------
| some-untaken-domain.com | Available |            | 1m 17s ago |
| youtube.com             | Taken     | 1mo 5d     | 1m 23s ago |
| google.net              | Taken     | 2mo 4d     | 1m 11s ago |
| twitch.tv               | Taken     | 5mo 4h     | 2d 23h ago |
| microsoft.com           | Taken     | 1y 3mo     | 1m 6s ago  |
| google.com              | Taken     | 4y 8mo     | 1m 28s ago |


~$ curl localhost:8051/youtube.com
   Domain Name: YOUTUBE.COM
   Registry Domain ID: 142504053_DOMAIN_COM-VRSN
   Registrar WHOIS Server: whois.markmonitor.com
   Registrar URL: http://www.markmonitor.com
   Updated Date: 2023-01-14T09:25:19Z
   Creation Date: 2005-02-15T05:13:12Z
   Registry Expiry Date: 2024-02-15T05:13:12Z
   # remaining data


~$ curl localhost:8051/queue
7 domains enqueued.

Query intervals:
    Domain taken                       7d
    Domain taken but expiration hidden 2d
    Domain free                        1d
    Missing parser                     7d
    Base errror retry delay            7d

| Domain                  | Next query | Last query |
-----------------------------------------------------
| some-untaken-domain.com | 23h 55m    | 4m 49s     |
| twitch.tv               | 4d 22m     | 2d 23h     |
| google.com              | 6d 23h     | 5m         |
| youtube.com             | 6d 23h     | 4m 55s     |
| google.net              | 6d 23h     | 4m 42s     |
| microsoft.com           | 6d 23h     | 4m 38s     |


~$ curl -d "dot.net" localhost:8051
dot.net watched! Status: Taken for 1y 15d (2025-01-25 05:00)


~$ curl localhost:8051/s/*.net
| Domain     | Status | Expiration | Queried     |
--------------------------------------------------
| google.net | Taken  | 2mo 4d     | 44m 27s ago |
| dot.net    | Taken  | 1y 15d     | 11s ago     |

Usage UI

There is a simple built-in browser UI written in solidjs. Open http://localhost:8051 (or the port your daemon is listening on) in your browser to see it.

Searching

The /s/{filter} endpoint searches through watched domains. Filters can contain letters, digits, *, or +.

* means a string of any length, and + means exactly one character. If the query does not contain * or +, it matches any domain containing the query substring. Example filters:

Url	Result
localhost/s/*.dev	Domains that end with .dev
localhost/s/*.++	Domains with exactly a two-letter TLD (pl, eu, etc.)
localhost/s/*.+++	Domains with exactly a three-letter TLD
localhost/s/google.*	Google domains
localhost/s/google*	Domains that begin with the string google
localhost/s/*.***	Domains with a TLD of three or more letters
localhost/s/+++.*	3-letter domains (without TLD)
localhost/s/+++*.*	4+ letter domains (without TLD)
localhost/s/gg	any domain containing the string gg

Note

The built-in HTTP server is not intended to face untrusted network traffic.