SaaS Guard Backend

Centralized permission and entitlement engine for SaaS applications.

Tech Stack

• Node.js (>=18.0.0)
• Express.js
• PostgreSQL
• Drizzle ORM
• Redis (Upstash)
• Clerk Auth
• JavaScript (ES Modules)

Setup

1. Install dependencies:

npm install

2. Create .env file from .env.example:

cp .env.example .env

3. Update .env with your configuration:
   • DATABASE_URL: PostgreSQL connection string
   • REDIS_URL: Redis connection string
   • CLERK_SECRET_KEY: Your Clerk secret key (required for authentication)

Development

Run the development server with nodemon:

npm run dev

The server will start on port 3000 (or the port specified in your .env file).

Health Check

Once the server is running, you can check the health endpoint:

curl http://localhost:3000/health

Project Structure

├── config/           # Configuration files (env, db)
├── constants/        # Application constants
├── controllers/      # Route controllers (use asyncHandler)
├── db/              # Database schemas and migrations
├── middlewares/     # Express middlewares (auth, error-handler, etc.)
├── models/          # Data models
├── routes/          # Route definitions
├── services/        # Business logic services
├── utilities/       # Utility functions (logger, errors, validators, async-handler)
└── index.js         # Application entry point

Key Features

Async Handler

All controllers use the asyncHandler wrapper to automatically handle errors. No need for try-catch blocks:

import asyncHandler from '../utilities/async-handler.js';

export const getUsers = asyncHandler(async (req, res) => {
  const users = await usersService.getAll();
  res.json({ success: true, data: users });
});

Clerk Authentication

• Uses @clerk/express package for authentication
• Clerk user IDs are strings, not integers
• Access user via req.userId or req.user (set by auth middleware)
• See controllers/example.controller.js for usage examples

Error Handling

• Custom error classes in utilities/errors.js
• Global error handler middleware catches all errors
• Consistent error response format

Scripts

• npm run dev - Start development server with nodemon
• npm start - Start production server
• npm run db:generate - Generate database migrations
• npm run db:migrate - Run database migrations
• npm run db:push - Push schema changes to database
• npm run db:studio - Open Drizzle Studio

License

ISC