@j2blasco/ts-auth

A TypeScript authentication abstraction library that eliminates vendor lock-in and provides mock-free testing for both frontend and backend authentication systems.

🎯 Why This Library?

Problem: Authentication providers (Firebase, Auth0, AWS Cognito) lock you into their specific APIs, making switching providers painful and testing complex.

Solution: A simple abstraction layer with complete testing implementations that work with any authentication provider.

🚀 Key Features

• 🔓 Vendor Independence: Switch between Firebase, Auth0, AWS Cognito, or any provider without changing business logic
• 🎭 No More Mocks: Real testing implementations instead of fragile mocks
• 🔄 Frontend + Backend: Separate interfaces for client and server concerns
• ✅ Contract Testing: Comprehensive test suites ensure implementations work correctly
• 📦 TypeScript First: Full type safety with Result types for error handling
• 🧩 Minimal API: Simple interfaces focusing on common authentication operations

📦 Installation

1npm install @j2blasco/ts-auth

🏗️ Architecture

The library provides separate interfaces for frontend and backend concerns:

Frontend Components

• IAuthFrontend: Client-side operations (login, signup, password reset)
• AuthFrontendTesting: Complete frontend testing implementation
• testAuthFrontend: Test suite for validating frontend implementations

Backend Components

• IAuthBackend: Server-side operations (token validation, user management)
• AuthBackendTesting: Complete backend testing implementation
• testAuthBackend: Test suite for validating backend implementations

🔧 Quick Start

Frontend Usage

1import { IAuthFrontend, AuthFrontendTesting } from '@j2blasco/ts-auth';
2
3// In your tests - no mocks needed!
4const auth = new AuthFrontendTesting();
5auth.addTestUser('test@example.com', 'password123');
6
7await auth.signInWithEmailAndPassword({
8  email: 'test@example.com',
9  password: 'password123',
10  persistent: true
11});
12
13// In production - implement the interface for your provider
14class FirebaseAuthFrontend implements IAuthFrontend {
15  // Implement all methods...
16}

Backend Usage

1import { IAuthBackend, AuthBackendTesting } from '@j2blasco/ts-auth';
2
3// In your tests
4const backendAuth = new AuthBackendTesting();
5
6const result = await backendAuth.signUpWithEmailPassword({
7  email: 'user@example.com',
8  password: 'password123'
9});
10
11const uid = result.unwrap().uid;
12
13// In production - implement for your provider
14class FirebaseAuthBackend implements IAuthBackend {
15  // Implement all methods...
16}

Testing Your Implementations

1import { testAuthFrontend, testAuthBackend } from '@j2blasco/ts-auth';
2
3describe('My Auth Implementation', () => {
4  // Frontend tests - comprehensive suite
5  testAuthFrontend(() => new MyFirebaseAuthFrontend());
6  
7  // Backend tests - comprehensive suite  
8  testAuthBackend(new MyFirebaseAuthBackend());
9});

🔍 Repository Structure

src/
├── frontend/
│   ├── core/
│   │   ├── auth-frontend.interface.ts          # Frontend interface definition
│   │   └── auth-frontend.generic.test.ts       # Generic test suite
│   └── providers/
│       └── testing/
│           ├── auth-frontend.testing.ts        # Testing implementation
│           └── auth-frontend.testing.test.ts   # Implementation tests
├── backend/
│   ├── core/
│   │   ├── auth-backend.interface.ts           # Backend interface definition
│   │   └── auth-backend.generic.test.ts        # Generic test suite
│   └── providers/
│       └── testing/
│           ├── auth-backend.testing.ts         # Testing implementation
│           └── auth-backend.testing.test.ts    # Implementation tests
└── index.ts                                    # Public exports

📋 Interface Overview

Frontend Interface (IAuthFrontend)

User-facing authentication operations:

• authState$ - Observable authentication state
• signInWithEmailAndPassword() - User login
• signUp() - User registration
• signOut() - User logout
• getIdToken() - Get current user token
• isEmailAvailable() - Check email availability
• changeEmail() - Update user email
• deleteAccount() - Delete user account
• triggerResetPasswordFlow() - Initiate password reset
• requestChangePassword() - Complete password change

Backend Interface (IAuthBackend)

Server-side authentication operations:

• onUserCreated$ / onUserDeleted$ - User lifecycle events
• getUidFromIdToken() - Validate and extract UID from token
• signInWithEmailAndPassword() - Administrative signin
• signInWithRefreshToken() - Token refresh
• signUpWithEmailPassword() - Administrative user creation
• changeEmail() - Administrative email change
• changePassword() - Administrative password change
• deleteUser() - Administrative user deletion
• getUidByEmail() - Lookup user by email

🧪 Testing Philosophy

This library follows Test-Driven Development principles:

1. Interface-First: Define the contract before implementation
2. Real Objects Over Mocks: Use complete implementations instead of mocks
3. Contract Testing: Generic test suites validate any implementation
4. Fail Fast: Comprehensive error handling with Result types

🔧 Development

Prerequisites

• Node.js 18+
• npm

Setup

1git clone https://github.com/j2blasco/ts-auth.git
2cd ts-auth
3npm install

Running Tests

1# Run all tests
2npm test
3
4# Run frontend tests only
5npm test -- src/frontend
6
7# Run backend tests only  
8npm test -- src/backend

Building

1npm run build

🤝 Contributing

1. Fork the repository
2. Create a feature branch: git checkout -b feature/your-feature
3. Write tests first (TDD approach)
4. Implement your feature
5. Ensure all tests pass: npm test
6. Submit a pull request

🛠️ Example Implementations

Want to see real implementations? Check out these examples:

• Firebase Implementation (coming soon)
• Auth0 Implementation (coming soon)
• AWS Cognito Implementation (coming soon)

📄 License

MIT License - see LICENSE file for details.

🙋 Support

• Issues: GitHub Issues
• Discussions: GitHub Discussions

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