Guards, Pipes, and Interceptors in NestJS

Some logic belongs to every request: authentication, input validation, response shaping. NestJS gives you dedicated mechanisms for each.

Guards for access control

Guards decide whether a request may proceed. Put authentication and role checks here to protect routes or whole controllers.

Pipes for transformation

Pipes validate and transform incoming data before it reaches your handler. Combine them with DTOs for type-safe, validated input.

Interceptors for cross-cutting work

Interceptors wrap handler execution for logging, caching, and response transformation. They can also handle timing and error observation.

Wrapping up

Using the right NestJS primitive keeps repeated concerns centralised and your handlers focused purely on business logic.