Why controllers handle incoming requests in NestJS - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to define a controller that handles HTTP GET requests.

NestJS

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

@Controller('cats')
export class CatsController {
  @[1]()
  findAll() {
    return 'This action returns all cats';
  }
}

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

APost

BPut

CGet

DDelete

Attempts:

3 left

💡 Hint

Common Mistakes

Using @Post() instead of @Get() for GET requests

Forgetting to import the decorator

The @Get() decorator marks the method to handle HTTP GET requests.

2fill in blank

medium

Complete the code to inject a service into the controller constructor.

NestJS

import { Controller } from '@nestjs/common';
import { CatsService } from './cats.service';

@Controller('cats')
export class CatsController {
  constructor(private readonly [1]: CatsService) {}
}

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

AcatsService

BCatsService

CserviceCats

Dcats

Attempts:

3 left

💡 Hint

Common Mistakes

Using the class name with uppercase as parameter name

Using unrelated variable names

The injected service is usually named in camelCase, matching the class name but starting lowercase.

3fill in blank

hard

Fix the error in the controller method to correctly handle a POST request with a body.

NestJS

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

@Controller('cats')
export class CatsController {
  @Post()
  create(@[1]() createCatDto: any) {
    return 'This action adds a new cat';
  }
}

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

ABody

BParam

CQuery

DHeaders

Attempts:

3 left

💡 Hint

Common Mistakes

Using @Param() to get body data

Forgetting to import the decorator

The @Body() decorator extracts the body of the POST request.

4fill in blank

hard

Fill both blanks to create a controller method that handles GET requests with a route parameter.

NestJS

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

@Controller('cats')
export class CatsController {
  @Get(':id')
  findOne(@[2]('id') id: string) {
    return `This action returns a cat with id ${id}`;
  }
}

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

AParam

BBody

CQuery

DHeaders

Attempts:

3 left

💡 Hint

Common Mistakes

Using @Body() or @Query() for route parameters

Not importing Param decorator

The @Param() decorator is used both in import and method parameter to access route parameters.

5fill in blank

hard

Fill all three blanks to create a controller method that handles PATCH requests with a route parameter and body.

NestJS

import { Controller, Patch, [1], [2] } from '@nestjs/common';

@Controller('cats')
export class CatsController {
  @Patch(':id')
  update(@[3]('id') id: string, @[2]() updateCatDto: any) {
    return `This action updates a cat with id ${id}`;
  }
}

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

AParam

BBody

CQuery

DHeaders

Attempts:

3 left

💡 Hint

Common Mistakes

Mixing up @Param() and @Body() decorators

Not importing both decorators

The @Param() decorator is used to get the route parameter, and @Body() to get the request body.