• Benjamin Kellermann
  • a lot of contributors of small code pieces


GNU AGPL v3 or higher (see file License)


  • ruby >=1.9
  • git >=1.6.5
  • ruby-gettext (for localization)
  • gettext, potool, make (optional, if you want to generate localization files)


  1. Place this application into a directory where cgi-scripts are evaluated.
  2. If you want to change some configuration, state it in the file config.rb (see config_sample.rb for help) to start with a default configuration.
  3. The webserver needs the permission to write into the directory
  4. You need .mo files in order to use localisation. You have 2 possibilities:

    1. Run this small script to fetch the files from the main server:

    sh cd $DUDLE_INSTALLATION_PATH for i in locale/??; do wget -O $i/dudle.mo https://dudle.inf.tu-dresden.de/locale/`basename $i`/dudle.mo done 2. Build them on your own. This requires gettext, ruby-gettext, potool, and make to be installed.

    sh sudo aptitude install gettext potool make make 5. In order to let access control work correctly, the webserver needs auth_digest support. It therefore may help to type:

    sh sudo a2enmod auth_digest 6. In order to get atom-feed support you need ruby-ratom to be installed. E.g.:

    sh sudo aptitude install ruby-dev libxml2-dev zlib1g-dev sudo gem install ratom 7. To make titles with umlauts working you need to check the encoding in .htaccess, e.g.

    sh SetEnv LC_ALL "en_US.UTF-8" 8. It might be the case, that you have to set some additional Variables in your .htaccess:

    sh SetEnv GIT_AUTHOR_NAME="http user" SetEnv GIT_AUTHOR_EMAIL=foo@example.org SetEnv GIT_COMMITTER_NAME="$GIT_AUTHOR_NAME" SetEnv GIT_COMMITTER_EMAIL="$GIT_AUTHOR_EMAIL" 9. If you installed dudle to a subdirectory (i.e. http://$YOUR_SERVER/$SOMEDIR/...), than you want to adopt the ErrorDocument directives in your .htaccess. (You need an absolute path here!) 10. Try to open http://$YOUR_SERVER/check.cgi to check if your config seems to work. 11. You may want to install a cronjob to cleanup dudle polls. See dudle_cleanup.sh for an example. 12. You can enable a maintenance mode if you need to change something with your installation. Using this mode, all users will see a static message and are not able to change anything. In order to enable this mode, create a file named /maintenance.html which may include a custom message. E.g.:

    sh echo "<div>We are updating the servers and expect to be online on 0 am, January 1st, 1970 (UTC).</div>" > $DUDLE_INSTALLATION_PATH/maintenance.html

Docker image

There are two docker image available * https://hub.docker.com/r/fonk/dudle/ with the code from here https://github.com/fonk/docker-dudle * https://github.com/jpkorva/dudle-docker

Pimp your Installation

  • If you want to create your own Stylesheet, you just have to put it in the folder $DUDLE_HOME_FOLDER/css/. Afterwards you may config this one to be the default Stylesheet. Examples can be found here:
    • https://dudle.inf.tu-dresden.de/css/ You can fetch the whole repo from https://github.com/kellerben/dudle-css
  • If you want to extend the functionality you might want to place a file main.rb in $DUDLE_HOME_FOLDER/extension/$YOUR_EXTENSION/main.rb Examples can be found here: https://dudle.inf.tu-dresden.de/extensions/ You can clone the whole sourcecode here:
    • https://github.com/kellerben/dudle-extensions-participate
    • https://github.com/kellerben/dudle-extensions-symcrypt
    • https://github.com/kellerben/dudle-extensions-asymcrypt
    • https://github.com/kellerben/dudle-extensions-gpgauth
    • https://github.com/kellerben/dudle-extensions-anonymous Note, that extensions are loaded in alphabetic order! The symcrypt extension e.g. needs the participate extension and therefore you need to name it “10-participate” in order to get executed first.


If you set $DUDLE_POEDIT_AUTO to your lang, poedit will launch automatically when building the application. E.g.:

git pull
make # will launch poedit if new french strings are to be translated
  • To add a new translation
  • first add a new folder for your language under $DUDLE_HOME_FOLDER/locale,
  • copy the dudle.pot file into your folder and name it dudle.po
  • translate sentences and phrases in your dudle.po file
  • add an entry for your language in dudle/dudle.rb at line 245