Middleware, Pipes, Guards & Interceptors — Chapter Quiz

Question 1

1

Which pipeline component decides whether a request may continue?

APipeBGuardCInterceptorDFilter

Guards implement CanActivate and return true/false (or a Promise of one) to allow or block the request.

Question 2

2

What does ParseIntPipe do?

AHashes the valueBConverts a string to an integer or throws BadRequestExceptionCAdds CORS headersDValidates a UUID

ParseIntPipe parses the raw param/query string; on failure it throws a 400.

Question 3

3

Which decorator marks an exception filter?

A@Catch()B@Filter()C@Throws()D@OnError()

@Catch(...) declares which exception types the filter handles.

Question 4

4

Where does middleware get registered?

AIn the @Module() decorator optionsBIn a module's configure(consumer) methodCOn the @Controller() decoratorDIn main.ts via NestFactory

A module implements NestModule and exposes configure(consumer) where it calls consumer.apply(Middleware).forRoutes(...).

Question 5

5

What is the role of an interceptor?

AValidate incoming payloadsBWrap the handler with before/after logic and transform responsesCAuthenticate the userDCatch thrown exceptions

Interceptors implement intercept(ctx, next) and can run logic before and after the handler, including transforming the result.

Question 6

6

HttpException is the base class for Nest's built-in HTTP error classes like NotFoundException.

TTrueFFalse

BadRequestException, NotFoundException, UnauthorizedException, etc. all extend HttpException.

Question 7

7

To read custom decorator metadata inside a guard, you inject the Nest helper ___.

Reflector.get/getAllAndOverride read metadata set via SetMetadata or custom decorators.

Question 8

8

Which of these run on every request that reaches a handler?

Select all that apply.

AGlobal guardsBGlobal pipesCGlobal interceptorsDThe @Module decorator

Globally registered guards, pipes, and interceptors execute on every request. @Module is a build-time decorator — it does not run per request.

Test what you learned.