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

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. 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 and install a caching proxy in front of DBF. See the Setup notes below.

To update your DBF installation, run git pull, ensure that all files are readable by your www user, and re-run carton install or cpanm --installdeps ..

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.

To update your Docker installation, fetch a new image from Docker Hub and re-start the container.

Setup

In hypnotoad mode (recommended), 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_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 then use a service supervisor of your choice to run hypnotoad index.pl (using Mojolicious' hypnotoad server). See examples/db-infoscreen.service for a systemd unit example.

For a quick&dirty setup on low-traffic sites you can also use morbo index.pl or perl index.pl daemon -m production. In this case, DBFAKEDISPLAY_LISTEN and DBFAKEDISPLAY_WORKERS have no effect. Morbo accepts IP and port configuration using the -l/--listen switch (default: http://*:3000); Daemon mode respects the MOJO_LISTEN environment variable (default: http://*:3000).

For public-facing installations, you may want to enable caching in the reverse proxy serving DBF. See examples/nginx-cache.conf and examples/nginx-site.conf for nginx examples.

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_v1.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; 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.

Resources

Mirrors of the db-infoscreen repository are available at