Proper error handling prevents crashes and improves debugging. Here's how to handle errors effectively in Node.js.
Custom Error Classes#
Async Error Handling#
Promise Error Handling#
Centralized Error Handler#
Unhandled Errors#
Service Layer Error Handling#
Try-Catch Patterns#
Logging Errors#
Testing Error Handling#
Best Practices#
Error Design:
✓ Use custom error classes
✓ Include error codes
✓ Separate operational from programmer errors
✓ Provide helpful messages
Handling:
✓ Always use try-catch with async/await
✓ Handle errors at appropriate level
✓ Clean up resources on failure
✓ Log errors with context
Response:
✓ Don't expose internal errors in production
✓ Use consistent error format
✓ Include request ID for debugging
✓ Return appropriate status codes
Monitoring:
✓ Log all errors
✓ Track error rates
✓ Alert on critical errors
✓ Review error logs regularly
Conclusion#
Robust error handling improves application reliability and debugging. Use custom error classes, centralized error handlers, and proper logging. Always catch async errors, handle cleanup on failure, and test error paths thoroughly.