i18n

What is i18n?

The i18n npm package is a lightweight internationalization library for Node.js applications. It provides a simple way to manage translations and localization for your application, supporting multiple languages and locales.

What are i18n's main functionalities?

Basic Setup

This code demonstrates how to set up the i18n package in a Node.js application. It configures the locales and the directory where translation files are stored, and initializes i18n middleware for use in an Express app.

const i18n = require('i18n');

// Configure i18n
i18n.configure({
  locales: ['en', 'es'],
  directory: __dirname + '/locales'
});

// Initialize i18n
app.use(i18n.init);

Translation

This feature allows you to translate strings based on the current locale. You can also include variables in the translation strings.

i18n.__('Hello'); // Returns 'Hello' in the current locale

// With variables
i18n.__('Hello %s', 'John'); // Returns 'Hello John' in the current locale

Changing Locale

This code demonstrates how to change the current locale dynamically. After setting the locale to 'es' (Spanish), the translation for 'Hello' will be returned in Spanish.

i18n.setLocale('es');
i18n.__('Hello'); // Returns 'Hola' if the Spanish translation is available

Using in Templates

This feature shows how to use i18n translations within template engines like EJS. The translated string is passed to the template as a variable.

app.get('/', function(req, res) {
  res.render('index', { title: res.__('Hello') });
});

Other packages similar to i18n

i18next

i18next is a powerful internationalization framework for JavaScript, including both client-side and server-side support. It offers more advanced features compared to i18n, such as nested translations, pluralization, and context-based translations.

polyglot

Polyglot.js is a small i18n helper library that provides a simple way to manage translations. It is less feature-rich than i18n but is very lightweight and easy to integrate into small projects.

node-polyglot

Node-Polyglot is a Node.js version of Polyglot.js, offering similar functionality for server-side applications. It is a good alternative for projects that require a minimalistic approach to internationalization.

README

i18n

Lightweight simple translation module with dynamic json storage. 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.

Install

npm install i18n

Usage

load and configure with express

in your app.js

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

// register helpers for use in templates
app.helpers({
  __: i18n.__
});

// or even a global for use in your app.js
var __= i18n.__;

simple usage

in your app

var greeting = __('Hello');

in your template (depending on your template compiler)

<%= __('Hello') %>

${__('Hello')}

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.

json file

the above will automatically generate a en.js 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."
}

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