i18n for node with expressJS

• key => value Style
• Deep file structure
• View helpers

var i18n_options = {}
var i18n = require('node-i18n')(i18n_options)

app.use(i18n.middleware) //call before app.use(app.router)

{
    default             : 'en'
  , enabled             : ['en']
  , dir                 : './assets/private/i18n'
  , helper_translate    : '__'
  , helper_path         : '__p'
  , helper_locale       : '__l'
}

dir is where translation files are stored. Relative to your express application file.
helper* are the avaible function in Jade templates

let's say you have a route /products where you want to implement i18n
Before implementing i18n your route would have look like so :

app.get('/products', function(req, res){
  res.end()
})

After

app.get(i18n.route('products'), function(req, res){
  res.end()
})

Note that the argument that i18n.route() takes is a RegExp, and we ommitted the / before products

Now this route will match /products and /en/products

As en is set to be the default, when making a request to /en/products you will be redirected to /products

Every translation file is JSON and must end with .json
You can have as many files as you want for each locale. This let you seperate content.
For example : en.json header_en.json footer_en.json

Each file start with the locale key.
You can now write your definition going how deep as you like in objects.

{ "en": {

  "baseline": "Welcome to my site",

  "header"  : {
    "menu"  : {
      "h1"  : "Hello {{name}} !",
      "h2"  : "What's up"
    }
  },
  
  "footer"  : {
    "who"   : "Who are we ?",
    "info"  : "Contact us by clicking {{{link|on this text}}}"
  }
  
}}

Labels are variables that you pass to your text definition and are defined in double brackets : "Hello {{name}} !"
If you call __('header.menu.h1', { name: 'Batman' }) you'll get Hello Batman

//dictionnary
{ "en": {
	"key" : "click on <a href='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/url'>this link</a>"
}}

The disadvantage of this is that you write html in your dictionnary and you don't have control of the <a/> tag in your template. This is where you want to use hooks :

//dictionnary
{ "en": {
	"key" : "click on {{{link|this link}}}"	
}}

Hooks use 3 brackets, the first paramater link is the key that will match with the object that you pass in the template and is separated with | with the second parameter wich is the translated text that you will call later on in your template like $link.

On your template you can now write :

__('key', { link: '<a href="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/url">$link</a>' })

Notice that $link refer to the translated text on the link key. You just need to add $
You will get the following :

"click on <a href="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/url">this link</a>"

Don't forget to unescape it in your jade as it's html

p= __('baseline')
p Current locale is #{__l}

div.header
   h1= __('header.menu.h1', { name: 'Batman' })
   h2= __('header.menu.h2')
   
div.footer
   a(href="#{__p('/contact')}")= __('footer.who')

   - var info = __('footer.info', { link: '<a href="mailto:[email protected]">$link</a>' })
   p !{info}

__l return current locale
__p('/contact') return given path prefixed with locale

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