Creating middleware in NestJS - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import the MiddlewareConsumer from NestJS.

NestJS

import { [1] } from '@nestjs/common';

Drag options to blanks, or click blank then click option'

AModule

BController

CMiddlewareConsumer

DInjectable

Attempts:

3 left

💡 Hint

Common Mistakes

Importing Controller instead of MiddlewareConsumer.

Forgetting to import MiddlewareConsumer.

The MiddlewareConsumer is imported from @nestjs/common to configure middleware in NestJS.

2fill in blank

medium

Complete the code to implement the NestJS middleware interface.

NestJS

export class LoggerMiddleware implements [1] {

Drag options to blanks, or click blank then click option'

ANestMiddleware

BPipeTransform

CExceptionFilter

DCanActivate

Attempts:

3 left

💡 Hint

Common Mistakes

Using PipeTransform instead of NestMiddleware.

Not implementing any interface.

Middleware classes in NestJS implement the NestMiddleware interface.

3fill in blank

hard

Fix the error in the middleware method signature.

NestJS

use(req: Request, res: Response, [1]) {

Drag options to blanks, or click blank then click option'

Anext: () => void

Bnext: NextFunction

Cnext: Function

Dnext: any

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect type like () => void or any.

Omitting the next parameter.

The use method in NestJS middleware receives next as a NextFunction type from Express.

4fill in blank

hard

Fill both blanks to apply middleware to all routes in a module.

NestJS

configure(consumer: [1]) {
  consumer
    .apply(LoggerMiddleware)
    .[2]('*');
}

Drag options to blanks, or click blank then click option'

AMiddlewareConsumer

BModuleRef

CforRoutes

Duse

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong parameter type in configure method.

Using 'use' instead of 'forRoutes' to apply middleware.

The configure method receives a MiddlewareConsumer to apply middleware. The forRoutes method applies it to all routes.

5fill in blank

hard

Fill all three blanks to create a middleware that logs the request method and URL, then calls next.

NestJS

export class LoggerMiddleware implements NestMiddleware {
  use(req: [1], res: [2], [3]) {
    console.log(`${req.method} ${req.url}`);
    next();
  }
}

Drag options to blanks, or click blank then click option'

ARequest

BResponse

Cnext: NextFunction

DHttpException

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect types for req or res.

Omitting the next parameter or using wrong type.

The middleware use method parameters are Request, Response, and next of type NextFunction. This allows logging and passing control to the next middleware.