moq-rs/dev/README.md

# Local Development

This is a collection of helpful scripts for local development.

## Setup

### moq-relay

Unfortunately, QUIC mandates TLS and makes local development difficult.
If you have a valid certificate you can use it instead of self-signing.

Use [mkcert](https://github.com/FiloSottile/mkcert) to generate a self-signed certificate.
Unfortunately, this currently requires [Go](https://golang.org/) to be installed in order to [fork](https://github.com/FiloSottile/mkcert/pull/513) the tool.
Somebody should get that merged or make something similar in Rust...

```bash
./dev/cert
```

Unfortunately, WebTransport in Chrome currently (May 2023) doesn't verify certificates using the root CA.
The workaround is to use the `serverFingerprints` options, which requires the certificate MUST be only valid for at most **14 days**.
This is also why we're using a fork of mkcert, because it generates certificates valid for years by default.
This limitation will be removed once Chrome uses the system CA for WebTransport.

### moq-pub

You'll want some test footage to broadcast.
Anything works, but make sure the codec is supported by the player since `moq-pub` does not re-encode.

Here's a criticially acclaimed short film:

```bash
mkdir media
wget http://commondatastorage.googleapis.com/gtv-videos-bucket/sample/BigBuckBunny.mp4 -O dev/source.mp4
```

`moq-pub` uses [ffmpeg](https://ffmpeg.org/) to convert the media to fMP4.
You should have it installed already if you're a video nerd, otherwise:

```bash
brew install ffmpeg
```

### moq-api

`moq-api` uses a redis instance to store active origins for clustering.
This is not relevant for most local development and the code path is skipped by default.

However, if you want to test the clustering, you'll need either either [Docker](https://www.docker.com/) or [Podman](https://podman.io/) installed.
We run the redis instance via a container automatically as part of `dev/api`.

## Development

**tl;dr** run these commands in seperate terminals:

```bash
./dev/cert
./dev/relay
./dev/pub
```

They will each print out a URL you can use to publish/watch broadcasts.

### moq-relay

You can run the relay with the following command, automatically using the self-signed certificates generated earlier.
This listens for WebTransport connections on WebTransport `https://localhost:4443` by default.

```bash
./dev/relay
```

It will print out a URL when you can use to publish. Alternatively, you can use `dev/pub` instead.

> Publish URL: https://quic.video/publish/?server=localhost:4443

### moq-pub

The following command runs a development instance, broadcasing `dev/source.mp4` to WebTransport `https://localhost:4443`:

```bash
./dev/pub
```

It will print out a URL when you can use to watch.
This will contain a random broadcast name so the below link won't work:

> Watch URL: https://quic.video/watch/REPLACE_WITH_NAME?server=localhost:4443

### moq-api

The following commands runs an API server, listening for HTTP requests on `http://localhost:4442` by default.

```bash
./dev/api
```

Nodes can now register themselves via the API, which means you can run multiple interconnected relays.
There's two separate `dev/relay-0` and `dev/relay-1` scripts to test clustering locally:

```bash
./dev/relay-0
./dev/relay-1
```

These listen on `:4443` and `:4444` respectively, inserting themselves into the origin database as `localhost:$PORT`.

There's also a separate `dev/pub-1` script to publish to the `:4444` instance.
You can use the exisitng `dev/pub` script to publish to the `:4443` instance.

If all goes well, you would be able to publish to one relay and watch from the other.