# proxy
This proxy is based on NGINX. The NGINX configuration is generated by a simple Node.js script which parses
the docker socket. NGINX acts as a reverse proxy server. The Node.js script reads the docker socket file to generate
a configuration for each running docker container. The base template for configuration is `nginx.conf.template`
All `*.template` files are written with [mustache-js](https://github.com/janl/mustache.js "GitHub") syntax.
The templates are assembled by the Node.js program.

## Docker Mapping
The Node.js script reads out the `/var/run/docker.sock` to get the containers of the host system via
[dockerode](https://github.com/apocas/dockerode "GitHub").

**Important:**
The proxy expects your backend containers to provide following structure:
* `stapps.version`-label of docker container to be set to a valid active version. See configuration....
* Service name for the backend container should be `backend` in docker-compose.yml. If you don't use docker-compose 
set `com.docker.compose.service`-label to `backend`.
* The proxy container to run with `--net="host"`
* A port exposed to the host machine. If you want to expose it only to the host machines internal loopback use following
syntax: `127.0.0.1:3000-3500:3000` in docker-compose or docker ports configuration. This will attach the internal 3000
port to the host's loopback on any port between 3000-3500. The proxy will see in the docker.sock which
port and ip was chosen. Internal loopback should be 127.0.0.1 tho.

## Configuration (Status Codes)
Config files can be added by multiple universities (adding files like `config/default-b-tu`) and selected via the
`NODE_APP_INSTANCE` environment variable.

- OutdatedVersions return a `HTTP 404`
- ActiveVersions return a `HTTP 503` if currently unavailable or the given code by running backend-node
- Unsupported versions (not configured as outdated or active) return a `HTTP 404`
- No version header given returns a `HTTP 300`

**NOTE:** The default configuration expects the client to set a version header: `X-StApps-Version=<version of app>`

## Logger
The proxy uses [@stapps/logger](https://gitlab.tubit.tu-berlin.de/stapps/logger). You can provide `NODE_ENV=production` 
and SMTP-Configuration via environment-variables for monitoring in production use. 

# Usage
Without ssl:
```sh
docker run --rm -v /var/run/docker.sock:/var/run/docker.sock --net="host" gitlab-registry.tubit.tu-berlin.de/stapps/proxy/master
```

With ssl:
```sh
docker run --rm --net="host" \
    -v /var/run/docker.sock:/var/run/docker.sock \
    -v <path to *.crt-file>:/etc/nginx/certs/ssl.crt \
    -v <path to *.key-file>:/etc/nginx/certs/ssl.key \
    gitlab-registry.tubit.tu-berlin.de/stapps/proxy/master
```

# Static Folder (docker run option: `-v <path to static folder>:/static`)
Der Zugriff erfolgt über: `http(s)://<url>/_static/<path-to-file>`

Beispiel Proxy auf Localhost für die Datei `static/test.json`: `http://localhost/_static/test.json`

## Bilder im Static Folder
Bilder sollten folgendermaßen abgelegt und benannt werden:

`<pfad analog zur imageURL aus der App>/<type>/<uid>-<size>.[jpg|png|gif]`

Beispiel:
`_static/images/Place/hautpmensa-thumbnail.jpg`

Aufgerufen wird das mit:
'https://server.deiner.uni.de/_static/images/Place/hauptmensa-thumbnail'

Bildgrößen sind: thumbnail, small, medium, large