🎯 NowaraJS - Singleton Manager

Managing singletons in TypeScript shouldn't require boilerplate everywhere. I built this package to have a single, centralized registry for all my singleton instances, no more scattered getInstance() patterns or global variables.

Why this package?

The goal is simple: One registry to rule them all.

Instead of implementing the singleton pattern in every class, you register instances once and retrieve them anywhere. Type-safe, predictable, and easy to test.

📌 Table of Contents

• Features
• Installation
• Usage
• API Reference
• License
• Contact

✨ Features

• 🔒 Type-Safe: Full TypeScript support with generics, no any casting.
• 🎯 Centralized: One place to manage all your singletons.
• ⚡ Lightweight: Minimal overhead, zero dependencies.

🔧 Installation

bun add @nowarajs/singleton-manager @nowarajs/error

⚙️ Usage

Registering Singletons

Register your instances once at startup. They'll be available everywhere.

import { SingletonManager } from '@nowarajs/singleton-manager';

class DatabaseConnection {
	private _isConnected = false;

	public constructor() {
		console.log('Database connection created');
		this._isConnected = true;
	}

	public query(sql: string): string[] {
		return ['result1', 'result2'];
	}
}

class ApiClient {
	public constructor(
		private readonly _baseUrl: string,
		private readonly _apiKey: string
	) {}

	public get baseUrl(): string {
		return this._baseUrl;
	}
}

// Register with any constructor signature
SingletonManager.register('DatabaseConnection', new DatabaseConnection());
SingletonManager.register('ApiClient', new ApiClient('https://api.example.com', 'key'));

Retrieving Instances

Same instance, every time. TypeScript knows the type.

const db1 = SingletonManager.get<DatabaseConnection>('DatabaseConnection');
const db2 = SingletonManager.get<DatabaseConnection>('DatabaseConnection');

console.log(db1 === db2); // true — same reference

db1.query('SELECT * FROM users'); // ✅ Type-safe

Checking & Unregistering

if (SingletonManager.has('ApiClient')) {
	const client = SingletonManager.get<ApiClient>('ApiClient');
	console.log(client.baseUrl);
}

// Need to swap an instance? Unregister first.
SingletonManager.unregister('DatabaseConnection');
SingletonManager.register('DatabaseConnection', new DatabaseConnection());

📚 API Reference

Full docs: nowarajs.github.io/singleton-manager

⚖️ License

MIT — Feel free to use it.

📧 Contact

• Mail: [email protected]
• GitHub: NowaraJS