Community  »  Applications  »  Horde

Horde Translation Guide

Author: Jan Schneider <>
Author: Chuck Hagenbuch <>
Author: Joris Braakman <>
Contact: (for administrators)
Contact: (for translators)

1   Administrator Guide

For translator documentation see the Translator Guide below.

1.1   GNU gettext, PHP and Horde

Horde uses GNU gettext for internationalization (i18n) and localization (l10n). The manual at is biased against C and using Emacs. This is more for Horde.

There is a good explanation for PHP and gettext at:

People seem to like learning from examples better, so I have used dutch (nl_NL) as an example everywhere.

There is a command line tool written in PHP for creating and managing translations in the /usr/bin/ or horde/bin/ directory. Usage instructions can be found in the Translator Guide below as well as instructions on how to start and maintain translations.

1.2   Translations don't work

If all or some translations don't work on your system, please follow the steps described below. If you want to ask for help either on the i18n mailing list or on Horde's bug system, please explain which steps you tried and which failed.

You might also find some more information in the FAQ.

Please note that Dutch (nl_NL) is only used as an example here. If you have problems with a certain translation use this translation's language code instead. Most locales only use the language part of the locale name (the first two lowercase letters) for the actual translation directories, i.e. nl in this example. Prominent exceptions from this rule are Chinese (zh_TW, zh_CN) and Brazilian Portuguese (pt_BR).

  1. Is this locale (nl_NL) installed at all?

    locale -a should list all locales installed on your system.

    On Debian and Ubuntu not all locales may be enabled by default. On Debian edit /etc/locale.gen and run locale-gen after you changed the list of enabled locales. On Ubuntu run locale-gen nl_NL for all locales that you want to install.

  2. Do you have any .mo files?

    Usually in /usr/share/locale/ e.g. /usr/share/locale/nl/LC_MESSAGES/

  3. Does gettext even work?

    Get a string to translate:

    $ strings /bin/tar | grep Memory
    Memory exhausted
    $ (LANG=nl_NL; LANGUAGE=nl_NL; LC_MESSAGES=nl_NL; gettext tar "Memory exhausted" )
    Geheugen uitgeput
  4. Does the local Horde file work?

    Assuming that you have put the translated Horde file in /var/www/horde/locale/nl/LC_MESSAGES/

    $ TEXTDOMAINDIR=/var/www/horde/locale LANG=nl_NL.utf8 LANGUAGE=nl_NL.utf8 LC_MESSAGES=nl_NL.utf8 gettext horde "Calendar" )

    Create a file in the horde directory, langtest.php:

    setlocale(LC_MESSAGES, 'nl_NL');
    // use the tar test.
    echo dgettext('tar', 'Memory exhausted');
    echo '<br />';
    // Specify location of translation tables
    bindtextdomain('horde', './locale');
    // Choose domain
    // Print the already tested message
    echo _("Calendar");
    echo '<br />';
    // this should print the same.
    echo dgettext('horde', 'Calendar');

    Output web browser:

    Geheugen uitgeput

1.3   Solaris

Since the .mo files are binary, they are platform specific. You have to rerun make in all po directories.

On Solaris 7, you don't have the Partial Locales (SUNWploc) and Supplementary Partial Locales (SUNWploc1) packages installed if you get:

$ LANG=nl_NL
couldn't set locale correctly

On Solaris 8, you must install the local packages required for the locales you desire (for example, you may need to install SUNWweuos for Western European locales or SUNWmeaos for Middle Eastern locales). The packages are located on Software Disk 1 of 2 in the directory: sol_8_1001_sparc/s0/Solaris_8/Product

This is what it should say:

Solaris 7:

$ pkginfo | grep ploc
system      SUNWploc       Partial Locales
system      SUNWploc1      Supplementary Partial Locales

Solaris 8:

$ pkginfo | grep euo
system      SUNWceuos      Central Europe OS Support
system      SUNWceuox      Central Europe 64-bit OS Support
system      SUNWeeuos      Eastern Europe OS Support
system      SUNWeeuox      Eastern Europe 64-bit OS Support
system      SUNWneuos      Northern Europe OS Support
system      SUNWneuox      Northern Europe 64-bit OS Support
system      SUNWseuos      Southern Europe OS Support
system      SUNWseuox      Southern Europe 64-bit OS Support
system      SUNWweuos      Western Europe OS Support
system      SUNWweuox      Western Europe 64-bit OS Support

The stuff is installed in /usr/lib/locale:

$ ls /usr/lib/locale/nl

It was reported that the HTTP server has to be linked to the same file as PHP on Solaris. Also, it may be required that be loaded before libc is loaded. If you are having conflicts, you may be able to reside them by starting apache with one of the following commands:

$ apachectl start

1.4   FreeBSD

You also need UTF-8 support in FreeBSD. This is not installed by default in FreeBSD versions before 5.3, you need to install the utf8locale-without-swidth-040319 package or port in older versions.

2   Translator Guide

2.1   Translation Tool

horde-translation is a small PHP script that should help translators doing their work.

Any feedback, bug reports and feature requests should be send to the i18n mailing list. This is also the right place for new translations and general discussions of i18n and l10n questions and problems.

horde-translation is installed to your /usr/bin/ directory by default, if using PEAR to install Horde. Otherwise it's located in horde/bin/

For a list of available commands run:

horde-translation help

For detailed help on a certain command run:

horde-translation help command

Additional information about creating translations and fixing problems can be found in the Administrator Guide.

2.1.1   Prerequisites

To run this script you'll need a PHP command line executable with gettext support compiled in, and the basic PEAR libraries. The script expects your PHP executable to be in the binary search path. If your PHP executable cannot be found, either edit the first line of translation to reflect your location or call the script like:

/usr/local/bin/php translation.

You'll need the gettext package version 0.12 or greater.

You'll need the PEAR packages Console_Getopt 0.11 or greater, Console_Table and File_Find. To install all needed packages, run:

pear upgrade PEAR Console_Getopt
pear install Console_Table File_Find

or download the newest package from the PEAR server and install them manually in your PEAR directory.

2.1.2   Creating a new translation

To create a new translation you first have to extract all gettext messages from the PHP sources. There are already template files with the .pot suffix in the locale directories that you can use if you have troubles extracting the messages, though these templates might be slightly outdated. Run:

horde-translation extract

You now have to create a new PO file for your language. A locale has the form ll_CC where ll is the two letter ISO 639 code of the language and CC the two letter ISO 3166 code of the country, e.g. de_DE, en_US or pt_BR. Only some languages require to specify the complete locale name, like Chinese (zh_CN or zh_TW). If you want to provide a country-specific language variant, e.g Brazilian Portuguese (pt_BR) or Canadian French (fr_CA) you need to use the full locale too. All other languages should only use the ll part of the locale as a parameter for the translation script.

horde-translation init -l ll

Now you can start the translation by editing the created locale/ll/LC_MESSAGES/[modulename].po files. You should fill out the the complete header of the created PO file, e.g.:

# Dutch translation for Horde.
# Copyright 2004-2017 Horde LLC (
# This file is distributed under the same license as the Horde package.
# Joris Braakman <>, 2004.
msgid ""
msgstr ""
"Project-Id-Version: Horde 4.0\n"
"POT-Creation-Date: 2004-04-14 10:30+0200\n"
"PO-Revision-Date: 2004-04-14 17:17+02:00\n"
"Last-Translator: Joris Braakman <>\n"
"MIME-Version: 1.0\n"
"Content-Type: text/plain; charset=UTF-8\n"
"Content-Transfer-Encoding: 8-bit\n"

To compile the translations to a binary format run:

horde-translation make -l ll

After you created the new translation you have to add entries for this locale in the configuration file horde/config/nls.php.

If you create a new translation for a certain module but there are already translations for the same language for other modules, then you should use a compendium. This will save you a lot of time and it will make translations much more consistent.

2.1.3   Compendiums

This tool utilizes a nice feature of gettext: compendium files. A compendium is a special PO file containing a set of translations recurring in many different packages. These compendiums will be used in the background without much intervention required. But you have to create and edit a compendium before you can use it.

To create a compendium of all existing translations for a certain locale run:

horde-translation compendium -l ll

The compendium.po being created will contain all modules' translations of this locale merged into a single file. You should take a closer look at this file because you may find a lot of special marked lines where you translated certain strings differently in the various modules. It's a good idea to fix the modules' translations now so that all modules use the same translations for the same strings. You can always recreate your compendium with the above command.

If you're maintaining translations for different branches and assumed that you have all modules of the development branch in one directory and all of the stalbe branch in another, you probably want to share a compendium between these directories.

To do this, you should first create a compendium in the stable branch, review it and fix all translations until you're happy with the results. Then create a second compendium in the head branch and include your first one with the --add option. Now fix the translations in this branch. If you're ready you can remove the first compendium and for now on use the compendium in the development branch for both branches. To do so, use the -c or --compendium option to specify a path to your compendium.

If you translate directly from a git checkout, this is usually not necessary because you work with all branches in the same directory and simply switch between them with git checkout.

2.1.4   Updating translations

The process of updating translations is a cycle where you extract new gettext strings from the sources, translate those new strings or update the already translated strings and compile them after.

To update the translation for a module, run:

horde-translation update -m modulename -l ll

This extracts the new strings from the sources and tries to update them from already existing translations in the compendium. You just have to translate all untranslated strings in the modulename.po file in the locale/ll_CC/LC_MESSAGES directory of the module you updated.

If extracting new strings fails for some reason, you can use the provided .pot file instead to update your translation:

horde-translation merge -m modulename -l ll

If your compendium is in a different directory than the translation script, you can specify the path to the compendium:

horde-translation update -m modulename -l ll -c /path/to/compendium

Once this is done, you can compile the translation by calling:

horde-translation make -m modulename -l ll

2.1.5   Extending existent translations

To have your own string (e.g. that you added to config files) displayed in several languages, you have to

  1. specify your texts as gettext arguments, in English, e.g. by using the _() function or Horde_Translation methods.
  2. edit the translation files for the required national languages,
  3. compile those translation files.

Be sure to keep records of your extensions, as you will probably have to repeat steps 2 and 3 after the next update.

E.g., you plan to offer two IMAP servers to select from in the Webmail login screen:

  1. In horde/imp/config/servers.php, you specify:

    $servers['Central'] = array(
       'name' => _("Central Mail Service"),
    $servers['CompSci'] = array(
       'name' => _("Mail Service of Computer Science Dpt.")
  2. In horde/imp/locale/de/imp.po you add two entries:

    msgid "Central Mail Service"
    msgstr "Zentraler Mailserver"
    msgid "Mail Service of Computer Science Dpt."
    msgstr "Mailserver Informatik"

    Likewise, you amend the translation files for other languages, as needed.

  3. You compile the translations using the commands:

    horde-translation make --module imp --no-compendium

2.1.6   "Raw" gettext strings

Horde provides a non-standard way to define a translatable string without having that string translated in the code. By using the Horde_Translation::r() method, the string will be marked as a translatable string and extracted by the Horde translation script, but the string will not be altered in the PHP code. Example:

// For a Horde package named Horde_Foo::
$str = Horde_Translation_Foo::r("Foo");
// -OR- For a Horde application::
$str = Horde_Translation_Core::r("Foo");

echo $str; // Output: Foo
echo _($str); // Output: [Translation of 'Foo']

2.2   Access Keys

Access keys, also known as shortcut keys, allow easy access to important functions, normally by hitting the Alt/Meta key in combination with another key. This key is marked in most user interfaces by being underlined.

As the access key is part of the word representing the action being executed, it is in the translators responsibility to select an access key when he translates these words. The action is always a link in Horde. The access key of a link is selected by prefixing it with an underscore.

The help link in the menu for example is always "_Help". This means that the "H" of the link will be underlined and the help can be opened by hitting Alt+H. In the PO file this string will appear as:

#: templates/menu/
msgid "_Help"
msgstr ""

A Spanish translator might want to translate this to:

#: templates/menu/
msgid "_Help"
msgstr "_Ayuda"

Translators of multibyte languages need to do this a bit differently as only ASCII characters are allowed for access keys. A Traditional Chinese translator might want to use:

#: templates/menu/
msgid "_Help"
msgstr "_H說明"

This renders to "說明(H)" in the interface and you can access this link with "H" as the access key.

2.3   Right-to-Left Languages

Translations for languages that are written from right to left might cause unexpected behavior if parenthesis or similar characters appear inside a translated string. To fix this broken string rendering you have to insert special Unicode codepoints into the translated string.

Before such a string in parenthesis, add the U+202D codepoint. If there is more right-to-left text to come after the closing parenthesis, add the U+202E codepoint after it. If using the PO mode of the Emacs editor you can add codepoints with the "ucs-insert" command.

2.4   Help Texts

2.4.1   Organization of the help files

The help texts are available in the horde/locale/, and horde/APP/locale/, directories, where APP is any Horde application. Every available translation is kept in a file called help.xml, in a subdirectory named according to the language name. Examples:

  • Horde's original help texts are in the horde/locale/en/help.xml file.
  • IMP's Brazilian help texts are in the horde/imp/locale/pt_BR/help.xml file.

When, for any desired application and locale, there is no help.xml file available, Horde's help system will use the application's locale/en/help.xml file, instead.

The help files must be encoded in the UTF-8 character set.

There is no compilation step involved: Every modification to, or addition of, a help.xml file takes immediate effect.

2.4.2   Syntax of the help files

Each help file must consist of syntactically valid XML code.

There are no predefined entities beyond the XML standard entities:

  • &lt; (less than)
  • &gt; (greater than)
  • &amp; (ampersand)
  • &apos; (ASCII apostrophe)
  • &quot; (ASCII quotation mark)

Any character available in the language's preferred character set can be entered as a numerical character reference (based on its Unicode scalar value), such as &#160; for the No-Break Space character.

The general structure can be learned from the existing examples; of course, the XML tags must be syntactically valid, and properly nested.


A PHP error message like Undefined index: url in /var/www/horde/lib/Horde/Help.php means that you have mis-spelled, or omitted, an attribute (url, in this example).

The following tags are available:

XML-Tag Parent Attributes Purpose
help List of help texts
entry help id Help text
title entry Entry in the help index
heading entry Level 2 heading
para entry Paragraph
ref para module, entry Link into the help system
eref para url External link
href para app, url Link into a Horde application
b para Bold text
i para Italic text on new line
pre entry Example box
tip entry Tip/hint box
warn entry Warning box

The elements marked para, in the Parent column, may also be used within pre, tip, and warn elements.

The following attributes are available:

XML-Tag Attribute Purpose/Syntax
entry id Anchor
ref module Index of Horde application, see horde/config/registry.php
entry Id of help file entry, see above
eref url arbitrary URL
href app Index of Horde application, see horde/config/registry.php
url URL within Horde application


<ref module="imp" entry="compose-attachments">selecting attachments</ref>
<eref url="">
      UW-IMAP quirk</eref>
<href app="turba" url="search.php">Address search</href>

The Translation Tool will introduce additional attributes:

XML-Tag Attribute Purpose/Syntax
entry state See Finishing a translation
md5 Used internally

2.4.3   Reference from the Horde applications

The typical incantation, e.g.:

<?php echo Horde_Help::link('imp', 'compose-buttons') ?>

will yield a link, adorned with the help.png icon, to the entry marked id="compose-buttons" in the IMP help file pertaining to the user's current locale. Usually, these links are placed in the template files, next to the item to be explained by the pertinent help entry.

The Horde menu will usually contain a general help item, which is generated in lib/Horde/Menu.php.

2.4.4   Creating a new translation

If necessary, define a suitable language name. E.g., if you plan to add an Austrian translation, you would use de_AT as your language name.

For Horde, and for all relevant applications, copy the help.xml files from the locale/en/ subdirectories to the locale/ll/ subdirectories, creating them if necessary.

Translate each new locale/ll/help.xml file, leaving all tags and attributes unchanged. Just translate the text between the tags.


The id attributes must be kept unchanged, under any circumstances.

If the application is already translated and only the help files are missing, then be sure to use the same terminology as the existing translation. In any case, try to use a lucid, coherent terminology.

2.4.5   Finishing a translation

If you want to submit a translation to be included in the Horde code base, make sure that you have completed all translations. Then run:

horde-translation make-help -l ll

This will mark all entries as being up-to-date so that you or other translators can later see which entries have been changed since then.

2.4.6   Updating an existing translation


horde-translation update-help -l ll

This will merge your existing help file with all changes from the original, English help file since your last translation. Changed entries are marked with the attribute state="changed", new entries with state="new". The original entry from the English help file is added in a comment below a changed entry, so that you can easily compare them.

Translate the remaining English phrases, like discussed above. When your finished, remove any English entries and follow the steps at Finishing a translation.

2.4.7   Extending existent translations

If you feel that some feature should be better explained to the end user, then proceed as following:

  1. Determine, whether you will have to extend an existing entry, or add a new one.
  2. In the latter case, choose a suitable id for your new help entry.
  3. Edit the existing entry in, or add a new entry to, the application's en/help.xml file. Change all translations needed in your site in the same way. Be sure to use the same id everywhere.
  4. If you have added a new entry, you might want to add a link to it from a template, as explained above in Reference from the Horde applications.
  5. If you feel that your enhancement may be useful to other users, file an enhancement request at with a patch including your changes to the template and the help.xml files.
  6. In any case, keep notes of your changes, so you can apply them to later versions if necessary.