Lingua CSS - snapshot version 01

A CSS based internationalization tool

Lingua CSS takes advantage of the CSS pseudo class lang, and changes the language based on it, which makes it work as an interesting internationalization tool.

So, let's say we want to translate a 'title' key in English, Spanish and Portuguese, so we provide a JSON structured language bundle file and lingua-css will output the following CSS:

/*Default language*/
.title:after {
    content: "Greetings!";
}

/*Portuguese*/
.title:lang(pt)::after {
    content: "Bem vindo!";
}

/*Spanish*/
.title:lang(es)::after {
    content: "Hola";
}

Installation

Use npm to install Lingua CSS (recommended):

$ npm install linguacss

Or, install it globally:

$ npm install -g linguacss

Usage

Command line

1. You can run lingua-css by providing an input language bundle file and the result will be output in stdout:

    $ lingua-css ./language-bundle.json

2. You can also pass an output file as a second option:

    $ lingua-css ./language-bundle.json ./css/i18n.css

3. A more sofisticated way is using flag options:

    $ lingua-css -i ./language-bundle.json -o ./css/i18n.css -t [data-language=\"{value}\"]

   The flag options are straightforward, however it's worth explaining them:

   • -i is the input file path and filename
   • -o is the output file path and filename
   • -t is the template value for the CSS selector. You must provide {value} to be replaced by the correct value. The default is a CSS class. eg? .title

4. Using Lingua CSS as an npm script. This is the most recommended way, as you don't have to install it globally.

   In your package.json, add the following entry to scripts:

     "scripts": {
       "linguacss": "linguacss ./language_bundle.json ./result.css"
     },

5. You can also import the library, and use it as a method. For example:

   var linguacss = require('linguacss');
      
   linguacss({
     filename: __dirname + '/bundle.json', 
     callback: buffer => { console.log(buffer); }
   });

Function options

When using Lingua CSS as an imported library into your project code, you must provide an options object. The following attributes are available in the options:

filename

This option is mandatory, as it is the input language bundle used to generate the i18n CSS. The value must be a string containing a filename, including its path.

callback

A callback function who will be called with the generated CSS style as the only argument.

valueTemplate

A string containing the CSS selector to be used for each text key.

It must contain the reserved expression {value} which will be replaced by the corresponding key. eg: [data-language="{value}"] with key 'message' will be converted to [data-language="message"].

By default, Lingua CSS will use a CSS class a selector

Language Bundle File Structure

The language bundle file must be a JSON following this structure displayed below. Each language must start with the language acronym, with the exception of the default language, whose name must be "default", as follows:

{
    "default": {
        "title": "Greetings!",
        "name": "name",
        "message": "This is a simple test at how to use lingua"
    },

    "pt": {
        "title": "Bem vindo!",
        "name": "nome",
        "message": "Este é um teste simples com o lingua"
    },

    "es": {
        "title": "Hola",
        "name": "nombre",
        "message": "Esta es una prueba sencilla en la forma de utilizar lingua"
    }
}

How it works?

Once you have built your CSS file, import it to your HTML page and add the CSS selectors to the elements you want the text to be displayed. For example:

    <div id="content">
        <h4 class="title"></h4>
        <p class="message"></p>
    </div>

The CSS language bundle will apply the classes title and message by adding the texts according to the default language, like this:

    <div id="content">
        <h4 class="title">Greetings</h4>
        <p class="message">This is a simple test at how to use lingua</p>
    </div>

Then, if you want to change language, simply change the attribute lang from your <body> tag:

    document.body.lang = 'pt';

This will automatically change the CSS classes (or whatever selector you decided to use) and the text will be updated:

    <div id="content">
        <h4 class="title">Bem vindo!</h4>
        <p class="message">Este é um teste simples com o lingua</p>
    </div>