path: root/README.md

db-infoscreen - App/Infoscreen for Railway Departures in Germany
---

[db-infoscreen homepage](https://finalrewind.org/projects/db-fakedisplay/)

db-infoscreen (formerly db-fakedisplay) shows departures at german train
stations, serving both as infoscreen / webapp and station board look-alike.

It aims to aggregate departure and train data from different sources and
combine them in a useful (and user-friendly) manner. It is intended both for a
quick glance at the departure board and for public transportation geeks looking
for details about specific trains.

There's a public [db-infoscreen service on
finalrewind.org](https://dbf.finalrewind.org/). You can also host your own
instance via carton/cpanminus or Docker if you like, see the Setup notes below.


Dependencies
---

 * perl >= 5.20
 * carton or cpanminus
 * build-essential
 * git

Installation
---

After installing the dependencies, clone the repository using git, e.g.

```
git clone https://git.finalrewind.org/db-fakedisplay
```

Make sure that all files (including `.git`, which is used to determine the
software version) are readable by your www user, and follow the steps in the
next sections.

Perl Dependencies
---

db-infoscreen depends on a set of Perl modules which are documented in
`cpanfile`. After installing the dependencies mentioned above, you can use
carton or cpanminus to install Perl dependencies locally.

In the project root directory (where `cpanfile` resides), run either

```
carton install
```

or

```
cpanm --installdeps .
```

and set `PERL5LIB=.../local/lib/perl5` before running index.pl or wrap it
with `carton exec hypnotoad index.pl`.

Note that you should provide imprint and privacy policy pages. Depending on
traffic volume, you may also want to increase the amount of worker processes.
See the Setup notes below.

Installation with Docker
---

A db-infoscreen image is available on Docker Hub. You can install and run it
as follows:

```
docker pull derfnull/db-fakedisplay:latest
docker run --rm -p 8000:8092 -v "$(pwd)/templates:/app/ext-templates:ro" db-fakedisplay:latest
```

This will make the web service available on port 8000.  Note that you should
provide imprint and privacy policy pages, see the Setup notes below.

Use `docker run -e DBFAKEDISPLAY_WORKERS=4 ...` and similar to pass environment
variables to the db-infoscreen service.

Setup
---

db-infoscreen respects the following environment variables:

| Variable | Default | Description |
| :------- | :------ | :---------- |
| DBFAKEDISPLAY\_LISTEN | `http://*:8092` | IP and Port for web service |
| DBFAKEDISPLAY\_STATS | _None_ | File in which the total count of backend API requests (excluding those answered from cache) is written |
| DBFAKEDISPLAY\_HAFAS\_API | `https://v5.db.transport.rest` | hafas-rest-api endpoint |
| DBFAKEDISPLAY\_HAFAS\_CACHE | `/tmp/dbf-hafas` | Directory for HAFAS cache |
| DBFAKEDISPLAY\_IRIS\_CACHE | `/tmp/dbf-iris-mian` | Directory for IRIS schedule cache |
| DBFAKEDISPLAY\_IRISRT\_CACHE | `/tmp/dbf-iris-realtime` | Directory for IRIS realtime cache |
| DBFAKEDISPLAY\_WORKERS | 2 | Number of worker processes (i.e., maximum amount of concurrent requests) |

Set these as needed, create `templates/imprint.html.ep` (imprint) and
`templates/privacy.html.ep` (privacy policy), and configure your web server to
pass requests for db-infoscreen to the appropriate port. See the
`examples` directory for imprint and privacy policy samples.

You can run the app using a Mojo::Server of your choice, e.g.  **perl
index.pl daemon -m production** (quick&dirty, does not respect all variables)
or **hypnotoad** (recommended). A systemd unit example is provided in
`examples/db-infoscreen.service`.

All code in this repository may be used under the terms of the BSD-2-Clause
(db-infoscreen, see COPYING) and MIT (jquery, jqueryui, and marquee libraries;
see the respective files) licenses.  Attribution is appreciated.

Background Data Updates
---

db-infoscreen can use <https://lib.finalrewind.org/dbdb/db_zugbildung_v0.json>
to show scheduled ICE/IC types (ICE 1/2/3/4/T, IC 1/2), wagon orders, and other
attributes. It expects the file to be provided in `share/zugbildungsplan.json`.

As this information is updated regularly, the file is not shipped as part of
this db-infoscreen distribution. It is recommended to retrieve it a few minutes
after midnight via a daily cronjob. See `examples/dbf_update_zugbildungsplan`
for a shell script.

DBF will periodically reload `share/zugbildungsplan.json`. You can use your
service supervisor (e.g. `systemctl reload db-infoscreen`) to force an
immediate reload. You may also ignore the file entirely; it is entirely
optional.

System requirements
---

Resource requirements depend on usage. For a few requests per second, about
200MB (600k inodes) cache and one or two CPU cores should be sufficient.
db-infoscreen typically needs 50MB RAM per worker process, though calculating
with 100MB per worker is recommended to leave a safety margin.

Licensing
---

This project follows the REUSE specification. The copyright of individual files
is documented in the file's header or in .reuse/dep5. The referenced licenses
are stored in the LICENSES directory.

The program code of db-infoscreen is licensed under the terms of the GNU AGPL
v3. HTML Templates and SASS/CSS layout are licensed under the terms of the
2-Clause BSD License. This means that you are free to host your own
db-infoscreen instance, both for personal/internal and public use, under the
following conditions.

* You are free to change HTML/SASS/CSS templates as you see fit (though you
  must not remove the copyright headers).
* If you make changes to the program code, that is, a file below lib/ or a
  db-infoscreen javascript file below public/static/js/, you must make those
  changes available to the public.

The easiest way of making changes available is by maintaining a public fork of
the Git repository. A tarball is also acceptable. Please change `source_url` in
`lib/DBInfoscreen.pm` to point to your Git repository / source archive if you
are using a version with custom changes.