I18n-js

Based on the idea of rails i18n gem, this is a JavaScript library for internationalization of strings in html5 applications.

Install

Add the following code to the section of your site:

<script type="text/javascript" src="I18n.js"></script>

Config

After including I18n.js you need to initialize it:

I18n.init(config)

Init function receives a configuration object with these options:

locales: array of available locales
translations: object containing translation objects for each locale
defaultLocale [optional]: locale used for defining translations, defaults to the first locale in locales array
initialLocale [optional]: intially selected locale, defaults to the first locale in locales array
warnForDefault [optional]: show a warning message if translation doesn't exist in default locale, defaults to true
warn [optional]: function returning a warning message string for missing locale, receives two arguments (string, locale)
pluralize [optional]: function returning pluralized translation string, receives three arguments (translations, count, locale)

Usage

I18n can be used for:

translation of raw strings
translation of strings with parameters
translation of string based on language plural rules

Example

Example initialization:

I18n.init({
  locales : ['en', 'de'],
  
  translations : {
    en : {
      "number-of-people" : {
        one : "There is 1 person in this room.",
        other : "There are :count people in this room."
      }
    },
    
    de : {
      "Good day" : "Guten tag",
      "Welcome, :name!" : "Wilkommen, :name!",
      "number-of-people" : {
        one : "Es ist 1 Person in diesem Zimmer.",
        other : "Es gibt :count Personen in diesem Zimmer."
      }
    }
  },
  
  initialLocale : 'de'
})

Example #1, raw string translation:

I18n.t("Good day") // Guten tag
I18n.setLocale('en')
I18n.t("Good day") // <div id="noTranslation">en: Good day</div>
I18n.setLocale('de')
I18n.t("Hello world") // <div id="noTranslation">de: Hello world</div>

Example #2, string with parameters:

I18n.t("Welcome, :name!", {name : "Josip"}) // Wilkommen, Josip!

Example #3, string based on language plural rules:

I18n.t("number-of-people", {count : 3}) // Es gibt 3 Personen in diesem Zimmer.
I18n.t("number-of-people", {count : 1}) // Es ist 1 Person in diesem Zimmer.

I18n.setLocale('en')
I18n.t("number-of-people", {count : 5}) // There is 5 people in this room.

Example warn function:

warn : function(string, locale) {
  return "You are missing a translation for string '" + string + "' in locale " + locale + "!";
}

Example pluralize function with support for french plural rules:

pluralize : function(translations, count, locale) {
  switch (locale) {
    case 'fr':
      return translations[count == 0 || count == 1 ? 'one' : 'other'];
    default :
      return translations[count == 1 ? 'one' : 'other'];
  }
}

Credits

Josip Bišćan, Infinum Ltd.

TODO

unit testing