Internationalization support

General guidelines

  • All config mode packages must be fully translatable, with complete English and German texts.
  • All new expert mode packages must be fully translatable. English texts are required.
  • German translations are recommended. Other supported languages, especially French, are nice-to-have, but not required. If you don’t know a language well, rather leave the translation blank, so it is obvious that there is no proper translation yet.
  • Existing expert mode packages should be made translatable as soon as possible.
  • The “message IDs” (which are the arguments to the translate function) should be the English texts.

i18n support in Gluon

Internationalization support is available in all components (models, view and controllers) of gluon-web-based packages. Strings are translated using the translate, _translate and translatef functions (translate for static strings, translatef for printf-like formatted string; _translate works the same as translate, but will return nil instead of the original string when no translation is available).

In views, the special tags <%:...%> can be used to translate the contained string.

Example from the gluon-config-mode-geo-location package:

local share_location = s:option(Flag, "location", translate("Show node on the map"))

Note that translations are namespaced: each package will only use its own translation strings by default. For this purpose, the package name must by specified in a package’s controller. It is possible to access a different translation package using the i18n function from models and view, which is necessary when strings from the site configuration are used, or packages do not have their own controller (which is the case for config mode wizard components).

local site_i18n = i18n 'gluon-site'
local msg = site_i18n._translate('gluon-config-mode:welcome')

Adding translation templates to Gluon packages

The i18n support is based on the standard gettext system. For each translatable package, a translation template with extension .pot can be created using the i18n-scan.pl script in the contrib directory:

cd package/gluon-web-mesh-vpn-fastd
mkdir i18n
cd i18n
../../../contrib/i18n-scan.pl ../files ../luasrc > gluon-web-mesh-vpn-fastd.pot

The same command can be run again to update the template.

In addition, the Makefile must be adjusted. Instead of OpenWrt’s default package.mk, the Gluon version (../gluon.mk for core packages) must be used. The i18n files must be installed and PKG_CONFIG_DEPENDS must be added:

...
include ../gluon.mk

PKG_CONFIG_DEPENDS += $(GLUON_I18N_CONFIG)
...
define Build/Compile
  $(call GluonBuildI18N,gluon-web-mesh-vpn-fastd,i18n)
endef

define Package/gluon-web-mesh-vpn-fastd/install
  ...
  $(call GluonInstallI18N,gluon-web-mesh-vpn-fastd,$(1))
endef
...

Adding translations

A new translation file for a template can be added using the msginit command:

cd package/gluon-web-mesh-vpn-fastd/i18n
msginit -l de

This will create the file de.po in which the translations can be added.

The translation file can be updated to a new template version using the msgmerge command:

msgmerge -U de.po gluon-web-mesh-vpn-fastd.pot

After the merge, the translation file should be checked for “fuzzy matched” entries where the original English texts have changed. All entries from the translation file should be translated in the .po file (or removed from it, so the original English texts are displayed instead).

Adding support for new languages

A list of all languages supported by gluon-web can be found in package/gluon.mk. New languages just need to be added to GLUON_SUPPORTED_LANGS, and a human-readable language name must be defined.