# NETfishing Discovery Server

An ephemeral public-room directory for NETfishing. It complements the game's existing direct ENet
transport: hosts advertise a room through HTTPS, browsers retrieve compatible rooms, and joining
still uses the authoritative host's UDP endpoint.

This first phase intentionally does not use coturn. TURN relays WebRTC traffic; NETfishing currently
uses ENet/UDP, so NAT traversal and relay transport are a separate future phase.

## Requirements

- Python 3.11 or newer
- A TLS reverse proxy for public deployment

There are no runtime Python package dependencies.

## Run locally

```bash
python3 -m netfishing_discovery
```

The default listener is `127.0.0.1:7770`.

```bash
curl http://127.0.0.1:7770/health
```

Run the focused tests with:

```bash
python3 -m unittest discover -v
```

## Configuration

Environment variables are documented in
[`deploy/netfishing-discovery.env.example`](deploy/netfishing-discovery.env.example).

The intended public topology is:

```text
NETfishing client -> HTTPS reverse proxy -> 127.0.0.1:7770 discovery service
NETfishing client -----------------------> advertised ENet/UDP host:port
```

Configure the Godot client with the reverse proxy's HTTPS origin through
`network/discovery/base_url` in `project.godot`. For local development, the
same value can be overridden without modifying the project by setting
`NETFISHING_DISCOVERY_URL` before launching the game.

The reverse proxy must preserve the client address in `X-Forwarded-For`, and
its own address must be listed in `NETFISHING_DISCOVERY_TRUSTED_PROXY_CIDRS`.
Apply ordinary request-rate limits to the write endpoints at the proxy. Do not
expose the Python listener directly to the public Internet.

Use the sample systemd unit in [`deploy/netfishing-discovery.service`](deploy/netfishing-discovery.service)
as a deployment starting point. The service keeps only active leases in memory, so it requires no
database, backups, or schema migrations.

## Connectivity boundary

Discovery makes a room findable; it does not make an unreachable ENet host
reachable. A host still needs its advertised UDP port forwarded/reachable from
the Internet. The existing coturn service cannot relay ENet packets because
TURN is a WebRTC transport component. NAT traversal or relay support therefore
remains a separate transport project and is not hidden inside the directory.

## API

See [`docs/API.md`](docs/API.md) for the versioned HTTP contract.

## Repository relationship

This is deliberately a separate repository from the Godot game. The game and service can version,
deploy, and roll back independently. The discovery API version is independent from NETfishing's
save schema and gameplay network protocol.