simplin.js

A simple, tiny Node.js module providing a basic multi-language system — dependency-free.

Aim of the project

A primary goal of this project is to provide bare-basic solution for multi-language feature (app localization), mainly for purposes within smaller Node.js projects. Conventional libraries might not be easy to learn and use, or they are just way too complex for a little hobby projects.

Installation

npm i simplin.js

How to start

1. Prepare en-US.json, that will serve both as default source of strings for your app, and as a template for the translators of your project.

   {
    "MSG_HELLO_WORLD": "Hello, world!",
    "MSG_NEW_MESSAGE": {
                         "zero": "You have no new message.",
                         "one": "You have %i new message.",
                         "other": "You have {0} new messages."
                       }
   }

   NOTICE: %i, %s, %0, {0} are just placeholders to be filled-up by your app dynamically and can be combined freely. However, if you are intending to pass multiple variables to a single string, you should stick with form %0…%9 or {0}…{9}. Translator can move them freely within the sentence, e.g. {2} alpha beta {0} gamma {1} delta, i.e. they don't have to be in ascending order.

   ZERO: Zero-forms are not used in some languages. Input argument 0 normally returns other string, unless you explicitely define special 0-case, on top of standard.

2. Where you are initializing your application, add

   const { StringProvider } = require("simplin.js");
   ...
   class MyApp {
    constructor() {
        this.locales = StringProvider
                       .load(path.resolve(__dirname, "../resources/locales")) //__dirname is pre-defined by your environment, similar to "pwd"
                       .setDefault("cs"); // you can omit setDefault(), in that case it's defaulted to 'en-US'
    }
   }

3. Anywhere in your app simply

   const { _ } = require("simplin.js");
   ...
   console.log(_("MSG_HELLO_WORLD"));
   console.log(_("MSG_NEW_MESSAGE", 3)); // 3 new messages

   Or, alternatively (without require() by referencing the previously initialized object)

   console.log(MyApp.locales.get("MSG_HELLO_WORLD");

4. Let translators to translate your project. Put all files to the same folder as en-US.json, they will be loaded automatically.

Getting a string in every language

You may need to get a string for each locale within a single object.

const { _A_ } = require("simplin.js");
...
const [localizedStrings, defaultLocaleString] = _A_("MSG_HELLO_WORLD");
////////////////////////////////////
console.log(localizedStrings)
=> {
     cs: "Ahoj, světe!",
     fr: "Bonjour le monde!"
   }
////////////////////////////////////
console.log(defaultLocaleString)
=> "Hello world!"

In case you'd need to concatenate the default language

localizedStrings[StringProvider.defaultLocale] = defaultLocaleString;