Express Auto Catch Router

Express Auto Catch Router is an enhanced Express router that automatically wraps asynchronous route handlers. This allows you to write cleaner code without worrying about wrapping every async function with try/catch blocks to forward errors to Express's error-handling middleware.

Features

• Automatic Error Handling: Wraps async/await route handlers so that any unhandled errors or promise rejections are automatically caught and passed to next().
• Broad Method Coverage: Supports all HTTP methods (GET, POST, PUT, DELETE, etc.) as well as use, all, and param.
• Easy Integration: Works seamlessly with your existing Express application without requiring modifications to your route handler signatures.
• Robust Async Detection: Uses a reliable method to detect async functions ensuring only those functions are wrapped.
• Router Options Support: Accepts all standard Express router options like caseSensitive, strict, and mergeParams.

Installation

Install via npm:

npm install @tumblewader/express-auto-catch-router

Or with yarn:

yarn add @tumblewader/express-auto-catch-router

Note: This package is compatible with Express 4.x versions only.

Usage

Replace your existing Express router with the enhanced router. For example:

const express = require('express');
const AsyncRouter = require('@tumblewader/express-auto-catch-router');

// Create an instance of the enhanced router
const router = new AsyncRouter().getRouter();

// Or with router options
const routerWithOptions = new AsyncRouter({
  caseSensitive: true,
  strict: true,
  mergeParams: true
}).getRouter();

// Define a route without manual try/catch handling:
router.get('/user/:id', async (req, res) => {
  // Any error thrown here will be automatically caught and passed to next()
  const user = await User.findById(req.params.id);
  if (!user) {
    throw new Error('User not found');
  }
  res.json(user);
});

// In your main app file
const app = express();
app.use('/api', router);

// Standard error-handling middleware
app.use((err, req, res, next) => {
  console.error(err);
  res.status(500).json({ error: err.message });
});

app.listen(3000, () => console.log('Server running on port 3000'));

API

AsyncRouter

constructor(options)

Creates a new instance of the enhanced router and automatically patches methods for async error handling.

Parameters:

• options (Object, optional): Router options object that will be passed to Express's Router.
  • caseSensitive (Boolean): Enable case sensitivity, default: false
  • strict (Boolean): Enable strict routing, default: false
  • mergeParams (Boolean): Preserve req.params values from parent router, default: false

getRouter()

Returns the underlying Express router instance with async error handling automatically applied to all route methods.

Contributing

Contributions are welcome! If you encounter any issues or have suggestions for improvements, please open an issue or submit a pull request.

License

This project is licensed under the MIT License. See the LICENSE file for details.

Repository

GitHub: https://github.com/tumblewader/express-auto-catch-router