langjs

langjs is a lightweight multi-language support package for TypeScript/JavaScript projects. It allows developers to define their own translation files in JSON format, switch between languages dynamically, and fetch localized strings for their applications.

Features

• Dynamically load translation files (JSON format).
• Easily switch between multiple languages.
• Simple API to retrieve translations for any key.
• TypeScript support for type safety.

Installation

You can install langjs from npm:

npm install @alirezakeshvari/langjs

Or using Yarn:

yarn add @alirezakeshvari/langjs

Usage

1. Setting up your translation files

Define your translations in JSON files for each language. For example, create en.json and fa.json like this:

• en.json

{
  "hello": "Hello",
  "goodbye": "Goodbye"
}

• fa.json

{
  "hello": "سلام",
  "goodbye": "خداحافظ"
}

2. Providing the paths to your translation files

In your project, use the setTranslations function to provide the paths to your translation files:

import { setTranslations, setLocale, _ } from "langjs";

// Set paths to your translation files
setTranslations({
  en: "./path/to/en.json",
  fa: "./path/to/fa.json",
});

3. Switching between locales

Use the setLocale function to switch between languages:

// Set locale to English
setLocale("en");
console.log(_("hello")); // Outputs: Hello

// Set locale to Farsi
setLocale("fa");
console.log(_("hello")); // Outputs: سلام

4. Fetching translations

Use the _ function to get translations based on the current locale:

console.log(_("goodbye")); // Outputs the translation for the current locale

If a translation key is not found, the key itself will be returned:

console.log(_("nonexistent_key")); // Outputs: nonexistent_key

API

setTranslations(localeFiles: { [locale: string]: string }): void

Sets the paths to your translation files. The object keys represent the locale code (e.g., en, fa), and the values represent the file paths to the respective JSON files.

• localeFiles: An object where the key is the locale (e.g., "en", "fa") and the value is the file path to the JSON file.

setLocale(locale: string): void

Sets the active locale for translations. This locale will be used to fetch translations when calling _.

• locale: The locale to switch to (e.g., "en", "fa").

_ (key: string): string

Fetches the translation for the given key from the currently set locale. If the key does not exist, it returns the key itself.

• key: The key for which to get the translation (e.g., "hello").

Example Project Setup

import { setTranslations, setLocale, _ } from "langjs";

// Set the translation files for English and Farsi
setTranslations({
  en: "./translations/en.json",
  fa: "./translations/fa.json",
});

// Switch to English
setLocale("en");
console.log(_("hello")); // Outputs: Hello

// Switch to Farsi
setLocale("fa");
console.log(_("hello")); // Outputs: سلام

Running Tests

You can run the unit tests with Jest. First, ensure that you've set up your project with the required development dependencies:

npm install

Then, run the tests:

npm test

License

This project is licensed under the MIT License.