# nginx caching reverse proxy config

This is a good-enough example configuration for a caching reverse proxy for HLS
live streams.

## See it in action

```bash
# Download and compile a local version of nginx
$ ./build.sh

# Run the example configuration
$ ./run.sh
```

Once running, check out [http://localhost:8080](http://localhost:8080). By The
example config proxies to `restream.dev`, so you should see a blank player page.
Feel free to check out the `restream.conf` file and tune it to your liking.

The build script doesn't litter your system with random junk. When you're done
you can just wipe the `./nginx` folder.

## Reverse proxying from existing nginx

If you don't wanna bother merging the config, you can just use your existing
nginx to reverse-proxy to this one. It'd look something like this:

```
         your server
         ----------------------------------
         |                                |
viewer --|--> main nginx --> this nginx --|--> upstream
         |      w/ SSL                    |
         ----------------------------------
```

You can just do something like this:

```
location / {
    proxy_pass http://127.0.0.1:8080/;
}
```

## Merging with your existing nginx

If you want to merge it with an existing nginx config, you can copy these
directives to the `http` block:

- `resolver` and `resolver_timeout` (if you plan on using a domain name for the
  upstream)
- `proxy_cache_path`
- `upstream`

And then you can copy the `server` block in too. If you want to merge it with an
existing `server`, you can just copy all the `proxy_` directives. Note that
it'll add caching to the whole `server` by default, so if you don't want that,
you can change `proxy_cache` to `off`, and then in the `location` blocks where
you do the reverse proxy, set `proxy_cache` back to `restream_cache`.

Feel free to tweak the parameters to fit your needs, but generally the values in
`restream.conf` should just work alright for caching live streams.

## Setting this up on a remote server

The convenience script `remote_setup.sh` can be used to ssh into a fresh remote
server, install nginx there, configure the upstream and set up SSL. This should
work on a fresh Ubuntu 20.04 server.

Run the script:

```
./remote_setup.sh \
  --domain relay1.stream.example.org \
  --upstream-server https://restream.dev:443 \
  --acme-email your.email@example.org \
  --target-server root@relay1.stream.example.org
```

**Important note**: you _must_ specify the protocol (`https://`) and the port
(`:443`) for the `--upstream-server` flag.

Once the script is done, your server should be accessible from
`https://relay1.stream.example.org` and proxying all requests to
`https://restream.dev`.

Example 2: setting up a relay for SPWN:

```
./remote_setup.sh \
    --domain relay1.stream.example.org \
    --upstream-server 'https://vod.spwn.jp:443' \
    --upstream-base '/spwn-archives/xxxxx/xxxx' \
    --acme-email acme@example.org \
    --target-server root@relay1.stream.example.org \
    --pass-header User-Agent '[user agent string]' \
    --pass-header Cookie '[redacted]' \
    --pass-header Referrer 'https://spwn.jp/'
```

**Notes**

- `--upstream-server`: Include the `https://` in front and the `:443` port
  number, and _do not_ include a trailing `/`.
- `--upstream-base`: The rest of the URL before the `index.m3u8` file. Start
  with a `/` but do not add a `/` at the end.