I18nService

This file defines the I18nService class, which provides internationalization (i18n) support for the @sodacore/core framework. It is responsible for loading translation files, managing available translations, and providing methods for translating strings and querying available languages.

---

Features

• Translation File Loading: Automatically loads all JSON translation files from a configurable directory.
• Translation Lookup: Translates keys to localized strings for a given language code, with fallback support.
• Language Management: Tracks available languages and provides a method to list them.
• Error Handling: Logs errors for missing translation files or failed loads.
• Configurable Paths: Supports custom translation directories via configuration.

---

Usage

import I18nService from './service/i18n';

const i18nService = new I18nService();
await i18nService.init();

const greeting = i18nService.translate('hello.world', 'fr', 'Hello, world!');
const availableLanguages = i18nService.getAvailableLanguages();

---

API

Properties

• config: Optional i18n configuration, injected via DI.
• translationsPath: Path to the directory containing translation files.
• _hasTranslations: Boolean indicating if any translations are loaded.
• translations: Record of loaded translations, keyed by language code.

Methods

async init(): Promise<void>

Initializes the service:

• Resolves the translations directory.
• Loads all translation files.
• Populates the translations property.

hasTranslations(): boolean

Returns true if translations have been loaded, otherwise false.

translate(query: string, languageCode: string, fallback?: string): string

Translates a key for the specified language code. Returns the translation, the fallback, or the original query if not found.

getAvailableLanguages(lower?: boolean): string[]

Returns an array of available language codes, including the default language.

private async getFilePaths(): Promise<string[] | null>

Scans the translations directory for .json files and returns their absolute paths.

private async loadTranslations(filePaths: string[]): Promise<Record<string, ITranslation>>

Loads and parses translation files, building the translations record.

---

How It Works

1. Initialization:

   • Determines the translations directory from config or defaults to ./translations.
   • Scans for all .json files in the directory.
   • Loads each file, extracting the language code from the filename (e.g., en-GB.json).
   • Populates the translations object with the loaded data.

2. Translation:

   • Looks up the translation for a given key and language code.
   • Returns the translation if found, otherwise returns the fallback or the original key.

3. Language Listing:

   • Returns all available language codes, including the default language.

---

Notes

• Translation files must be named using the format lang-COUNTRY.json (e.g., en-GB.json).
• Each translation file should export a JSON object mapping keys to translated strings.
• The service logs errors for missing or malformed translation files.
• Designed for use with the Sodacore dependency injection and service lifecycle.