Rate limiting with throttler in NestJS - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is the purpose of rate limiting in web applications?

Rate limiting helps control how many requests a user or client can make in a certain time. It protects servers from overload and stops abuse like spamming or attacks.

beginner

In NestJS, which package is commonly used to implement rate limiting?

The @nestjs/throttler package is used to add rate limiting easily in NestJS applications.

intermediate

How do you apply rate limiting globally in a NestJS app using Throttler?

You import ThrottlerModule in your root module with settings like ttl (time to live) and limit (max requests). Then add ThrottlerGuard as a global guard to enforce limits on all routes.

beginner

What does the 'ttl' option mean in ThrottlerModule configuration?

'ttl' stands for time to live. It sets the time window in seconds during which the request count is tracked for rate limiting.

intermediate

How can you customize rate limits for specific routes in NestJS with Throttler?

You use the @Throttle(limit, ttl) decorator on controllers or methods to set custom limits per route, overriding global settings.

What does the 'limit' option in ThrottlerModule specify?

A Maximum number of requests allowed in the ttl window

B Time in seconds to wait before next request

C Number of users allowed to access the app

D Size of the request payload

The 'limit' sets how many requests a client can make within the ttl time window.

Which decorator is used to set rate limits on a specific route in NestJS?

A @Throttle()

B @RateLimit()

C @Limit()

D @Guard()

The @Throttle() decorator sets custom rate limits on controllers or methods.

What happens when a client exceeds the rate limit in NestJS Throttler?

A The server crashes

B The request is blocked and a 429 Too Many Requests error is returned

C The request is queued for later

D The client is logged out automatically

Exceeding the limit returns a 429 error to inform the client to slow down.

How do you enable ThrottlerGuard globally in a NestJS app?

A Set global: true in ThrottlerModule options

B Add @Global() decorator to ThrottlerModule

C Use app.useGlobalGuards(new ThrottlerGuard()) in main.ts

D Import ThrottlerGuard in every controller

You call app.useGlobalGuards(new ThrottlerGuard()) in the main bootstrap file.

Which of these is NOT a benefit of using rate limiting?

A Preventing server overload

B Stopping brute force attacks

C Reducing spam requests

D Improving user interface design

Rate limiting helps with security and performance, but not directly with UI design.

Explain how to set up global rate limiting in a NestJS application using the Throttler package.

Think about module imports and global guards.

Describe how you can customize rate limits for individual routes in NestJS with throttler.

Focus on decorators for route-level control.