Middleware functions are essential for processing requests and responses in Server-Side APIs. They:
- Handle Authentication: Validate user credentials before proceeding.
- Log Requests: Track and log API activity for debugging or auditing.
- Modify Responses: Add headers or transform data before sending it to the client.
- Error Handling: Capture and process errors to provide meaningful feedback.
- Performance Optimization: Apply rate limiting or caching at intermediate steps.
Middleware layers enhance API functionality, modularity, and security.