Building Scalable APIs with Node.js and Express

Building scalable APIs requires careful consideration of architecture, performance, and maintainability. This guide covers essential practices for creating robust Node.js APIs.

## Architecture Best Practices

1. **Modular Structure**

• - Separate routes, controllers, and services
• - Implement dependency injection
• - Use middleware for cross-cutting concerns

2. **Error Handling**

• - Create custom error classes
• - Implement global error handling middleware
• - Proper error logging and monitoring

## Performance Optimization

1. **Caching Strategies**

• - Implement Redis for frequently accessed data
• - Use in-memory caching where appropriate
• - Implement proper cache invalidation

2. **Database Optimization**

• - Use proper indexing
• - Implement connection pooling
• - Optimize queries for performance

## Security Measures

1. **Authentication & Authorization**

• - Implement JWT authentication
• - Role-based access control
• - Rate limiting and API throttling

2. **Data Validation**

• - Input sanitization
• - Request validation middleware
• - Schema validation using libraries like Joi

## Code Example