rynDNS/README.md

<h1 align="center">rynDNS</h1>

<h4 align="center">
	A simplistic Dynamic DNS-ish server.
</h4>

`rynDNS` is a simple REST-API for `name` to `ip` resolving in the spirit of Dynamic DNS. Clients can `PUT` their `ipv4` address up to be read by other clients. Access is controlled via `api_key` and permissions (`read`, `write`, `admin`). No special client side application needed, just something to do a `POST` request like `wget`, `curl` or `httpie`. 

<p align="center">
    <strong>
        <a href="https://demo.api.pdev.dev">Demo</a> 
        • <a href="#getting-started">Getting started</a> 
        • <a href="#rest-api">Rest API</a> 
        • <a href="#configuration">Configuration</a>
        • <a href="#roadmap">Roadmap</a>
	</strong>
</p>

## Getting Started

This repo includes a [`Dockerfile`](Dockerfile) with an accompanying [`docker-compose.yml`](docker-compose.yml). To build and launch the container simply run:
```bash
docker-compose up
```
Once the container is build and running it will create a default admin account and post its randomly generated api key to the console:
```
ryndns | No admin accounts in Database, adding default: admin
ryndns | Created default admin with api_key: 3NJbP4tS.39b92576.062...
```
The API is now accessible at http://localhost:3000/rynDNS.
```bash
# using httpie
API_SERVER=http://localhost:3000/rynDNS
API_KEY=X-API-Key:3NJbP4tS.39b92576.062142e6451df545d5034ca8f6050b80ff3e9689f20d5e45d72d160fa7e1cf32

# list all clients
http get $API_SERVER/admin/clients $API_KEY

# creating a client
JSON_REQUEST_BODY='{                                      
  "name": "clientA",
  "description": "Client across the river",
  "permission": "rw",
  "public_ip": false
}'
http post $API_SERVER/admin/client $API_KEY <<< $JSON_REQUEST_BODY

# Alternatively using query strings (be sure to encode special characters in the param values)
API_KEY='X-API-Key=MdSUxrQQ.d5d40cd9.e2s1BsQEqmSE5MqyHYbDBVxGr/KY4BYIV5QkdjiCOF0='
CLIENT_PARAMS='name=clientA&description=Client+across+the+river&permission=rw&public_ip=false'
http post $API_SERVER/admin/client?$API_KEY&$CLIENT_PARAMS
```
Updating a write client's `ipv4`:
```bash
# using httpie
API_SERVER=http://localhost:3000/rynDNS
API_KEY=X-API-Key:zW3If4s5.3d6129cc.48d41d2a28b16a9a274d3f407026aee2b82cddbb3c11a5496ffe329c78e5d54b

# automatically set ip based on request itself
http put $API_SERVER/client $API_KEY

# set a custom ip for the client
JSON_REQUEST_BODY='{
  "ipv4": "115.16.0.99"
}'
http put $API_SERVER/client $API_KEY <<< $JSON_REQUEST_BODY
```
Reading a write client's `ipv4` with a read client:
```bash
# using httpie
API_SERVER=http://localhost:3000/rynDNS
API_KEY=X-API-Key:zW3If4s5.28aef5cb.d502cb94ba0802c6363f95ecb3a70de7e2e4b889779e435b7c033f2c72ed4f20
CLIENT_NAME=write_client

http get $API_SERVER/clients/$CLIENT_NAME $ API_KEY

# returns clients name and ipv4  as json
#{
#  "name": "write_client",
#  "ipv4": "115.16.0.99"
#}
```
## REST API
A detailed and interactive specification can be found in the [demo](https://demo.api.pdev.dev) which is a render of the OpenAPI specification [api.yml](api.yml) with `swager-ui`.

All requests except for `/public/*` require a valid `X-API-Key` header with appropriate permission.

**Experimental:** All parameters (including `X-API-Key`) can be passed as query string.

The following is a quick overview of the available commands.

### Admin
Permission `x`

* [`POST /admin/client`](https://demo.api.pdev.dev/#/admin/create_client) - Create or update a client and retrieve a new API key
* [`PUT /admin/client`](https://demo.api.pdev.dev/#/admin/update_client) - Update an existing client
* [`GET /admin/clients`](https://demo.api.pdev.dev/#/admin/get_all_client) - Retrieve all clients information
* [`GET /admin/clients/{client_name}`](https://demo.api.pdev.dev/#/admin/get_client) - Retrieve client information
* [`DELETE /admin/clients/{client_name}`](https://demo.api.pdev.dev/#/admin/delete_client) - Delete an existing client

### Client (write)
Permission `w`

* [`PUT /client`](https://demo.api.pdev.dev/#/client%20(write)/update_client_ip) - Update ipv4 client information based on request IP or body if present
* [`DELETE /client`](https://demo.api.pdev.dev/#/client%20(write)/delete_client_ip) - Delete the requesting client's ipv4 information

### Client (read)
Permission `r`

* [`GET /clients/{client_name}`](https://demo.api.pdev.dev/#/client%20(read)/get_client_ip) - Get ipv4 client information

### Public
Client attribute `public_ip: true`

* [`GET /public/{client_name}`](https://demo.api.pdev.dev/#/public/get_public_client_ip) - Get ipv4 client information

## Configuration

The `rynDNS` server can be configured with environment variables, these can also be set in the docker environment:

```bash
# set to run app in subdirectory [default: /]
RAILS_RELATIVE_URL_ROOT: /rynDNS
# set maximum number of clients in db [default: 250]
RAILS_MAX_CLIENTS: 250
# set custom api key prefix [default: randomly generated (saved and restored if using docker)]
API_KEY_PREFIX: zW3If4s5
# set custom header name for api key [default: X-API-Key]
API_KEY_HEADER: X-API-Key
# set to reset the admin account, this will output a new api key on the console when starting the server [default: 0]
RAILS_RESET_ADMIN: 1
# set app to run as demo [default: 0]
RAILS_API_DEMO: 1
# [DOCKER only] set cycle to reset demo data [default: 60m]
RAILS_DEMO_RESET: 60m
```

## Roadmap

* `Public Mode` - to allow for quick deployment without having to create clients/api-keys in a trusted environment (see #1)
* ~~Support Query Strings - as alternative to api key in header and json body~~ (merged 297016e799)
  * add full test coverage for query strings (considered experimental until then)
  * add query strings to `api.yml` and additional examples
* DNS Server in Docker container - resolve `client_name`s via DNS server