Developer Area/Language strings

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Revision as of 17:20, 29 July 2013 by Aaronw (talk | contribs) (langconfig.php)

For internationalization (i18n) and localization (l10n) reasons, all strings that are displayed to the user in Mahara are stored in "lang strings" and printed via the get_string($identifier, $section) function, rather than being placed directly in the code. This function will check to see if the user has any foreign language langpacks instealled, or any custom lang files, and will use the string from those if present. Otherwise, it will fall back to the core lang files.

How to call get_string()

The function get_string() takes these parameters:

  • identifier: The name of the lang string, unique within its section. The identifier must be acceptable as a PHP key. By convention, it's often the same as the English contents of the string, in all lowercase without spaces. Alternately, it can represent the purpose of the string rather than the exact wording of the string.
  • section: The file that the lang string lives in. This is technically optional; if left off, it will default to "mahara", a section that contains many common core strings.
  • params: (Optional) A lang string can contain one or more sprintf() params. If present in the lang string, matching param values will be expected from the get_string() call that uses the string, and will be placed in. Params are helpful for translation into languages with different word orders.

Anatomy of a lang file

A lang will be named {section}.php, where "section" is the section value to pass to get_string(). It will contain a series of lines adding keys to an array called "$string". By convention it begins with a check to prevent direct access from a browser.

defined('INTERNAL') || die();

$string['changepassworddesc'] = 'New password';
$string['changepasswordotherinterface'] = 'You may change your password through a different interface.';
$string['oldpasswordincorrect'] = 'This is not your current password.';

Where the lang files are

  • Core lang files live under $cfg->dirroot/lang/en.utf8/{section}.php
  • Plugin lang files live under $cfg->dirroot/{plugintype}/{pluginname}/lang/en.utf8/{plugintype}.{pluginname}.php
    • Note that the "section" for a plugin when invoking it in get_string(), is "{plugintype}.{pluginname}". For example: "", "import.leap2a", "blocktype.contactinfo"
    • Subplugins, such as a blocktype that belongs to an artefact, live under {$cfg->dirroot}/artefact/{pluginname}/blocktype/{blockname}/lang/en.utf8/blocktype.{blockname}.php and have "blocktype.{blockname}" as their section.
  • Foreign language langpacks are installed into your dataroot directory: $cfg->dataroot/langpacks/{langcode}
    • {langcode} will be the code for the language. For example "pt.utf8", "es.utf8", "en_US.utf8" etc
  • Local lang files live under $cfg->dirroot/local/lang/{langcode}/{section}.php


The main point of this system is to allow for Mahara to be translated. See the "langpacks" documentation for more on that. Basically, you download a langpack from, unzip it, and put it in $cfg->dataroot/langpacks/. Then, users are presented with a language selection menu at the login screen.

If a particular lang string is not present in the langpack, then the English language string from Mahara core is used, unless the language specifies a parent language and the parent language's langpack is installed.


Languages contain a small amount of configuration data. This goes in a "langconfig.php" core lang file. The following values are the most important:

  • thislanguage: The name of the language, in the language. This is displayed in the language selection menu that users see.
  • locale: A list of computer locale strings which this language matches. See the other lang packs for an idea of what these should look like.
  • parentlanguage: (Optional) If this is supplied, then for untranslated strings Mahara will attempt to find a translation in the parent language (if it's installed).
  • pluralrule and pluralfunction:
    • TODO

Custom lang strings

Many Mahara installations may wish to overwrite only a few lang strings. The easiest way to do this is to create custom lang files under the /local directory. If present, the strings in these files will take priority over strings in the core lang files or langpack lang files.

Custom lang files don't need to translate 100% of the lang file they're over-riding. They can contain as few strings as you to care to actually override.


// This file lives under /var/www/mahara/local/lang/en.utf8/mahara.php
defined('INTERNAL') || die();

$string['yes'] = 'Yessir!';
$string['login'] = 'Sign in!";

You can place foreign language files, and plugin language files under local/lang as well. These are all acceptable:

  • local/lang/en.utf8/mahara.php
  • local/lang/en.utf8/blocktype.contactinfo.php
  • local/lang/pt.utf8/