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Node.js express connect module for i18n and l10n support
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This module abides by the user's language preferences and makes it available throughout the app.

This module abides by the Mozilla L10n way of doing things.

The module abides.


This module is under development, currently being extracted from BrowserID.


You should install Gnu gettext to get msginit, xgettext, and other tools.


npm install i18n-abide

In your app where you setup express or connect:

var i18n = require('i18n-abide');

  supported_languages: ['en-US', 'de', 'es', 'db-LB', 'it-CH'],
  default_lang: 'en-US',
  debug_lang: 'it-CH',
  translation_directory: 'i18n'

This block sets up the middleware and views with gettext support. We declare support for English, German, Spanish, and two debug locales (more on this later).

In your routes, you can use the gettext function in .js files.

exports.homepage = function(req, resp) {
  resp.render('home', {title: req.gettext("Hey, careful, man, there's a beverage here!")});

In your layout files, you can add

<!DOCTYPE html>
<html lang="<%= lang %>" dir="<%= lang_dir %>">
    <meta charset="utf-8">

In your templates files, you can use the gettext function in .ejs files:

<p><%= gettext("This will not stand, ya know, this aggression will not stand, man.") %></p>

i18n-abide also provides a format function for string interpolation.

These are both server side translations and client side translations. Server side works out of the box and is the most common use case.

If you also want to do client-side translations, i18n-abide provides lib/gettext.js and you can do the same in .js and .ejs files.

Setup Gettext

$ mkdir -p locale/templates/LC_MESSAGES
$ ./node_modules/.bin/extract-pot --locale locale .

If you look in locale/templates/LC_MESSAGES/messages.pot you will see your strings have been extracted. Edit this file and make sure charset is set to UTF-8.

If there are certain files or directories you want to exclude, use --exclude one or more times. Example:

$ extract-pot --locale locale . --exclude tests --exclude examples

Example messages.pot:

"Content-Type: text/plain; charset=UTF-8\n"
"Content-Transfer-Encoding: 8bit\n"

#: ./routes.js:81
msgid "Hey, careful, man, there's a beverage here!"
msgstr ""

#: views/404.ejs:5
msgid "This will not stand, ya know, this aggression will not stand, man."
msgstr ""

To create po files in bulk, do:

$ for l in en_US de es db_LB; do
    mkdir -p locale/${l}/LC_MESSAGES/
    msginit --input=./locale/templates/LC_MESSAGES/messages.pot \
            --output-file=./locale/${l}/LC_MESSAGES/messages.po \
            -l ${l}

If you look at locale/en_US/LC_MESSAGES/messages.po, it will be very similar to your template messages.pot file.

This creates .po files which you can give to localizers to translate your copy.

Let's put the i18n-abide tools in our path:

$ export PATH=$PATH:node_modules/i18n-abide/bin

And run a string merge:

$ ./locale

A merge takes strings from our .pot files and pushes them into our .po files. If you have podebug installed, it also automatically translates db-LB.

Debugging and Testing

db-LB is a special debug locale. To trigger it, set your Browser or Operating System language to Italian (Switzerland) which is it-CH. This fake locale db-LB will be triggered, it is David Bowie speak for the region of Labyrinth. Oh, hell ya a Dude / Bowie Mashup. That just happened.

Example: locale/db_LB/LC_MESSAGES/messages.po

"Content-Type: text/plain; charset=UTF-8\n"
"Content-Transfer-Encoding: 8bit\n"

#: routes.js:81
msgid "Hey, careful, man, there's a beverage here!"
msgstr "‮Hǝʎ´ ɔɐɹǝɟnʅ´ ɯɐu´ ʇɥǝɹǝ,s ɐ qǝʌǝɹɐƃǝ ɥǝɹǝ¡"

#: views/404.ejs:5
msgid "This will not stand, ya know, this aggression will not stand, man."
msgstr "‮⊥ɥıs ʍıʅʅ uoʇ sʇɐup´ ʎɐ ʞuoʍ´ ʇɥıs ɐƃƃɹǝssıou ʍıʅʅ uoʇ sʇɐup´ ɯɐu·"

And we will compile .po files into .mo files.

$ locale/

Now, start up your Node server and visit a page you've wrapped strings in Gettext...

See docs/ for full details.

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