i18n

lightweight translation module with dynamic json storage

npm install i18n
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i18n

Lightweight simple translation module with dynamic json storage. Supports plain vanilla node.js apps and should work with any framework (like express, restify and probably more) that exposes an app.use() method passing in res and req objects. Uses common __('...') syntax in app and templates. Stores language files in json files compatible to webtranslateit json format. Adds new strings on-the-fly when first used in your app. No extra parsing needed.

Build Status

Install

npm install i18n

Test

npm test

Load

// load modules
var express = require('express'),
    i18n = require("i18n");

now you are ready to use a global i18n.__('Hello'). Global assumes you share a common state of localization in any time and any part of your app. This is usually fine in cli-style scripts. When serving responses to http requests you'll need to make sure that scope is NOT shared globally but attached to your request object.

Configure

Minimal example, just setup two locales

i18n.configure({
    locales:['en', 'de']
});

list of configuration options

i18n.configure({
    // setup some locales - other locales default to en silently
    locales:['en', 'de'],

    // you may alter a site wide default locale
    defaultLocale: 'de',

    // sets a custom cookie name to parse locale settings from  - defaults to NULL
    cookie: 'yourcookiename',

    // where to store json files - defaults to './locales'
    directory: './mylocales',

    // whether to write new locale information to disk - defaults to true
    updateFiles: false,

    // what to use as the indentation unit - defaults to "\t"
    indent: "\t",

    // setting extension of json files - defaults to '.json' (you might want to set this to '.js' according to webtranslateit)
    extension: '.js',
});

Example usage in gobal scope

In your app, when not registered to a specific object:

var greeting = i18n.__('Hello');

Example usage in express.js

In an express app, you might use i18n.init to gather language settings of your visitors and also bind your helpers to response object honoring request objects locale, ie:

// Configuration
app.configure(function() {

    [...]

    // default: using 'accept-language' header to guess language settings
    app.use(i18n.init);

    [...]
});

in your apps methods:

app.get('/de', function(req, res){
  var greeting = res.__('Hello');
});

in your templates (depending on your template engine)

<%= __('Hello') %>

${__('Hello')}

Examples for common setups

API

__()

Translates a single phrase and adds it to locales if unknown. Returns translated parsed and substituted string.

// template and global (this.locale == 'de')
__('Hello'); // Hallo
__('Hello %s', 'Marcus'); // Hallo Marcus

// scoped via req object (req.locale == 'de')
req.__('Hello'); // Hallo
req.__('Hello %s', 'Marcus'); // Hallo Marcus

// passing specific locale
__({phrase: 'Hello', locale: 'fr'}); // Salut
__({phrase: 'Hello %s', locale: 'fr'}, 'Marcus'); // Salut Marcus

__n()

Plurals translation of a single phrase. Singular and plural forms will get added to locales if unknown. Returns translated parsed and substituted string based on count parameter.

// template and global (this.locale == 'de')
__n("%s cat", "%s cats", 1); // 1 Katze
__n("%s cat", "%s cats", 3); // 3 Katzen

// scoped via req object (req.locale == 'de')
req.__n("%s cat", "%s cats", 1); // 1 Katze
req.__n("%s cat", "%s cats", 3); // 3 Katzen

// passing specific locale
__n({singular: "%s cat", plural: "%s cats", locale: "fr"}, 1); // 1 chat
__n({singular: "%s cat", plural: "%s cats", locale: "fr"}, 3); // 3 chat

__n({singular: "%s cat", plural: "%s cats", locale: "fr", count: 1}); // 1 chat
__n({singular: "%s cat", plural: "%s cats", locale: "fr", count: 3}); // 3 chat

setLocale()

Setting the current locale (ie.: en) globally or in current scope.

setLocale('de');
setLocale(req, 'de');
req.setLocale('de');

getLocale()

Getting the current locale (ie.: en) from current scope or globally.

getLocale(); // --> de
getLocale(req); // --> de
req.getLocale(); // --> de

getCatalog()

Returns a whole catalog optionally based on current scope and locale.

getCatalog(); // returns all locales
getCatalog('de'); // returns just 'de'

getCatalog(req); // returns all locales
getCatalog(req, 'de'); // returns just 'de'

req.getCatalog(); // returns all locales
req.getCatalog('de'); // returns just 'de'

Optionally manual attaching helpers for different template engines

In general i18n has to be attached to the response object to let it's public api get accessible in your templates and methods. As of 0.4.0 i18n tries to do so internally via i18n.init, as if you were doing it in app.configure on your own:

app.use(function(req, res, next) {
    // express helper for natively supported engines
    res.locals.__ = res.__ = function() {
        return i18n.__.apply(req, arguments);
    };

    [...]

    next();
});

Different engines need different implementations, so yours might miss or not work with the current default helpers. This one showing an example for mustache in express:

// register helper as a locals function wrapped as mustache expects
app.use(function (req, res, next) {
    // mustache helper
    res.locals.__ = function () {
      return function (text, render) {
        return i18n.__.apply(req, arguments);
      };
    };        

    [...]

    next();
});

You could still setup your own implementation. Please refer to Examples below, post an issue or contribute your setup.

Output parsing of expressions

As inspired by gettext there is currently support for sprintf-style expressions. Named parameters are on roadmap.

sprintf support

var greeting = __('Hello %s, how are you today?', 'Marcus');

this puts Hello Marcus, how are you today?. You might add endless arguments and even nest it.

var greeting = __('Hello %s, how are you today? How was your %s.', 'Marcus', __('weekend'));

which puts Hello Marcus, how are you today? How was your weekend.

variable support

you might even use dynamic variables as they get interpreted on the fly. Better make sure no user input finds it's way to that point as they all get added to the en.js file if not yet existing.

var greetings = ['Hi', 'Hello', 'Howdy'];        
for (var i=0; i < greetings.length; i++) {
    console.log( __(greetings[i]) );
};

which puts

Hi
Hello
Howdy

basic plural support

two different plural forms are supported as response to count:

var singular = __n('%s cat', '%s cats', 1);
var plural = __n('%s cat', '%s cats', 3);

this puts 1 cat or 3 cats and again these could get nested:

var singular = __n('There is one monkey in the %%s', 'There are %d monkeys in the %%s', 1, 'tree');
var plural = __n('There is one monkey in the %%s', 'There are %d monkeys in the %%s', 3, 'tree');

putting There is one monkey in the tree or There are 3 monkeys in the tree

Storage

Will get modular support for different storage engines, currently just json files are stored in filesystem.

json file

the above will automatically generate a en.json by default inside ./locales/ which looks like

{
    "Hello": "Hello",
    "Hello %s, how are you today?": "Hello %s, how are you today?",
    "weekend": "weekend",
    "Hello %s, how are you today? How was your %s.": "Hello %s, how are you today? How was your %s.",
    "Hi": "Hi",
    "Howdy": "Howdy",
    "%s cat": {
        "one": "%s cat",
        "other": "%s cats"
    },
    "There is one monkey in the %%s": {
        "one": "There is one monkey in the %%s",
        "other": "There are %d monkeys in the %%s"
    },
    "tree": "tree"
}

that file can be edited or just uploaded to webtranslateit for any kind of collaborative translation workflow:

{
    "Hello": "Hallo",
    "Hello %s, how are you today?": "Hallo %s, wie geht es dir heute?",
    "weekend": "Wochenende",
    "Hello %s, how are you today? How was your %s.": "Hallo %s, wie geht es dir heute? Wie war dein %s.",
    "Hi": "Hi",
    "Howdy": "Hallöchen",
    "%s cat": {
        "one": "%s Katze",
        "other": "%s Katzen"
    },
    "There is one monkey in the %%s": {
        "one": "Im %%s sitzt ein Affe",
        "other": "Im %%s sitzen %d Affen"
    },
    "tree": "Baum"
}

Logging & Debugging

Logging any kind of output is moved to debug module. To let i18n output anything run your app with DEBUG env set like so:

$ DEBUG=i18n:* node app.js

i18n exposes three log-levels:

  • i18n:debug
  • i18n:warn
  • i18n:error

if you only want to get errors and warnings reported start your node server like so:

$ DEBUG=i18n:warn,i18n:error node app.js

Combine those settings with you existing application if any of you other modules or libs also uses debug

Changelog

  • 0.4.1: stable release; merged/closed: #57, #60, #67 typo fixes; added more examples and new features: #53, #65, #66 - and some more api reference
  • 0.4.0: stable release; closed: #22, #24, #4, #10, #54; added examples, clarified concurrency usage in different template engines, added i18n.getCatalog
  • 0.3.9: express.js usage, named api, jscoverage + more test, refactored configure, closed: #51, #20, #16, #49
  • 0.3.8: fixed: #44, #49; merged: #47, #45, #50; added: #33; updated: README
  • 0.3.7: tests by mocha.js, added this.locale to __ and __n
  • 0.3.6: travisCI, writeFileSync, devDependencies, jslint, MIT, fixed: #29, #9, merged: #25, #30, #43
  • 0.3.5: fixed some issues, prepared refactoring, prepared publishing to npm finally
  • 0.3.4: merged pull request #13 from Fuitad/master and updated README
  • 0.3.3: merged pull request from codders/master and modified for backward compatibility. Usage and tests pending
  • 0.3.2: merged pull request #7 from carlptr/master and added tests, modified fswrite to do sync writes
  • 0.3.0: added configure and init with express support (calling guessLanguage() via 'accept-language')
  • 0.2.0: added plurals
  • 0.1.0: added tests
  • 0.0.1: start

Licensed under MIT

Copyright (c) 2011-2013 Marcus Spiegel marcus.spiegel@gmail.com

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

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