Chapter quiz · Middleware-Style Plugins

Test what you learned.

8 questions on Middleware-Style Plugins. Pass 70% to clear the chapter.

Quiz

Middleware-Style Plugins — Chapter Quiz

Eight questions on helmet, CORS, rate limit, multipart, static, compress, formbody, proxy, circuit breakers, and caching.

0/ 9

Question 1
1
What does @fastify/helmet do?
ASets a set of security-related HTTP response headers (CSP, X-Frame-Options, etc.)BAdds rate limitingCImplements TLS for the appDSanitizes incoming JSON payloads
Helmet sets headers like Content-Security-Policy, Strict-Transport-Security, X-Frame-Options, and others. It doesn't sanitize inputs or terminate TLS.
Question 2
2
Which plugin handles file uploads via multipart/form-data?
A@fastify/formbodyB@fastify/multipartC@fastify/staticD@fastify/compress
@fastify/multipart parses multipart streams. @fastify/formbody handles application/x-www-form-urlencoded bodies.
Question 3
3
@fastify/cors must be registered **before** routes are added for it to handle preflight requests for those routes.
TTrueFFalse
Plugin order matters in Fastify — CORS hooks must be registered before the routes they protect, so the OPTIONS preflight handler is wired correctly.
Question 4
4
To allow at most 100 requests per minute per IP with @fastify/rate-limit, set max: 100 and timeWindow to one ____.
timeWindow accepts a human-readable string like '1 minute', '1 hour', or a millisecond number.
Question 5
5
What does this route serve?
```
await app.register(import('@fastify/static'), {
  root: '/srv/public',
});
// GET /logo.png
```
A/srv/public/logo.pngB/public/logo.pngC404 — there is no prefixDThe file at the URL path joined to the project root
Without a prefix, @fastify/static serves files directly off root. A request for /logo.png resolves to /srv/public/logo.png.
Question 6
6
What does @fastify/compress do?
ACompresses incoming request bodiesBNegotiates and applies gzip/brotli/deflate to outgoing responsesCMinifies your JS bundles at build timeDCompresses log lines
It content-negotiates an encoding (Accept-Encoding) and pipes the response through gzip / brotli / deflate. It also handles decompression of incoming bodies when configured.
Question 7
7
When is a circuit breaker useful?
AWhen a downstream dependency keeps failing — stop hammering it for a whileBWhen you want to enforce CORSCWhen testing your routesDWhen you need to deduplicate logs
Circuit breakers (e.g. @fastify/circuit-breaker) trip after repeated downstream failures and fast-fail subsequent calls for a cooldown window, protecting both you and the dependency.
Question 8
8
Which plugins are typically registered in production-facing Fastify apps?
Select all that apply.
A@fastify/helmetB@fastify/corsC@fastify/rate-limitD@fastify/compressE@fastify/dev-only-debugger
Helmet, CORS, rate limit, and compress are common in production. @fastify/dev-only-debugger is not a real plugin.