Redirect responses in NestJS - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to send a redirect response to '/home' using NestJS.

NestJS

return response.[1]('/home');

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

Asend

Bredirect

Cjson

Dstatus

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'send' instead of 'redirect' causes the server to send data instead of redirecting.

Using 'status' alone does not perform a redirect.

In NestJS, the redirect method on the response object sends a redirect response to the client.

2fill in blank

medium

Complete the code to inject the response object in a NestJS controller method.

NestJS

import { Response } from 'express';

@Get()
handleRequest(@[1]() response: Response) {
  return response.redirect('/dashboard');
}

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

ARes

BBody

CReq

DQuery

Attempts:

3 left

💡 Hint

Common Mistakes

Using '@Req()' instead of '@Res()' injects the request, not the response.

Using '@Body()' or '@Query()' injects parts of the request, not the response.

The @Res() decorator injects the response object in NestJS controller methods.

3fill in blank

hard

Fix the error in the code to properly redirect with status 301 in NestJS.

NestJS

return response.status([1]).redirect('/new-url');

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

A301

B200

C404

D500

Attempts:

3 left

💡 Hint

Common Mistakes

Using 200 status code does not perform a redirect.

Using 404 or 500 causes errors instead of redirect.

Status code 301 means a permanent redirect. Using status(301) before redirect() sets this correctly.

4fill in blank

hard

Fill both blanks to create a redirect response with status 302 and URL '/login'.

NestJS

return response.status([1]).[2]('/login');

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

A302

Bredirect

Csend

D404

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'send' instead of 'redirect' does not redirect.

Using status 404 is not a redirect.

Status 302 means temporary redirect. Use status(302) and then redirect() to send the redirect.

5fill in blank

hard

Fill all three blanks to create a NestJS controller method that redirects to '/profile' with status 307.

NestJS

import { Controller, Get, Res } from '@nestjs/common';
import { Response } from 'express';

@Controller('user')
export class UserController {
  @Get('redirect')
  redirectToProfile(@[1]() response: Response) {
    return response.status([2]).[3]('/profile');
  }
}

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

ARes

B307

Credirect

DReq

Attempts:

3 left

💡 Hint

Common Mistakes

Using '@Req()' instead of '@Res()' injects request, not response.

Using wrong status codes like 200 or 404.

Using 'send' instead of 'redirect' method.

Use @Res() to inject response, status code 307 for temporary redirect, and redirect() method to send the redirect.

Practice

1. What is the primary purpose of using res.redirect() in a NestJS controller?

easy

A. To send the user to a different URL automatically

B. To send JSON data as a response

C. To handle database queries

D. To log user requests

Solution

1. Step 1: Understand the function of res.redirect()

   This method is used to send an HTTP redirect response to the client, telling the browser to go to a different URL.

2. Step 2: Compare with other options

   Options A, B, and C describe other unrelated tasks like logging, sending JSON, or querying databases, which are not the purpose of res.redirect().

3. Final Answer:

   To send the user to a different URL automatically -> Option A

4. Quick Check:

   Redirect means sending user to another URL [OK]

Hint: Redirect means sending user to a new URL [OK]

Common Mistakes:

• Confusing redirect with sending JSON response
• Thinking redirect handles database operations
• Assuming redirect logs requests

2. Which of the following is the correct way to inject the response object to use res.redirect() in a NestJS controller method?

easy

A. Use @Body() decorator

B. Use @Req() decorator

C. Use @Res() decorator

D. Use @Param() decorator

Solution

1. Step 1: Identify the decorator for response object

   In NestJS, @Res() is used to inject the response object to access methods like redirect().

2. Step 2: Verify other decorators

   @Req() is for request, @Body() is for request body data, and @Param() is for route parameters, none provide the response object.

3. Final Answer:

   Use @Res() decorator -> Option C

4. Quick Check:

   Response object injection = @Res() [OK]

Hint: Use @Res() to get response object for redirect [OK]

Common Mistakes:

• Using @Req() instead of @Res() for response
• Confusing @Body() with response injection
• Using @Param() which is for route params

3. Consider this NestJS controller method:

async redirectToGoogle(@Res() res) {
  res.redirect('https://google.com');
}

What will happen when this method is called?

medium

A. The user will be redirected to 'https://google.com' with status 302

B. The user will receive a JSON response with the URL

C. The server will throw an error because status code is missing

D. Nothing happens because redirect needs a status code

Solution

1. Step 1: Understand default behavior of res.redirect()

   When called with only a URL, res.redirect() sends a 302 status code by default, redirecting the user to the given URL.

2. Step 2: Check if status code is mandatory

   Status code is optional; if omitted, 302 is used automatically, so no error occurs.

3. Final Answer:

   The user will be redirected to 'https://google.com' with status 302 -> Option A

4. Quick Check:

   Redirect URL alone defaults to 302 status [OK]

Hint: Redirect without status defaults to 302 [OK]

Common Mistakes:

• Thinking status code is required for redirect
• Expecting JSON response instead of redirect
• Assuming server error without status code

4. Identify the error in this NestJS controller method:

@Get('go')
async go(@Res() res) {
  res.redirect(301, 'https://example.com');
  return 'Redirecting';
}

medium

A. Status code 301 is invalid for redirect

B. Returning a string after res.redirect() causes an error

C. Missing await before res.redirect()

D. res.redirect() must be called without parameters

Solution

1. Step 1: Understand res.redirect() behavior

   Calling res.redirect() sends the response immediately. Returning a value after sending response causes NestJS to throw an error because response is already sent.

2. Step 2: Check other options

   Status code 301 is valid for permanent redirect, no await needed as redirect is synchronous, and redirect requires parameters.

3. Final Answer:

   Returning a string after res.redirect() causes an error -> Option B

4. Quick Check:

   Don't return after sending response [OK]

Hint: Don't return after res.redirect() sends response [OK]

Common Mistakes:

• Thinking 301 is invalid status code
• Adding await unnecessarily
• Calling redirect without parameters

5. You want to create a NestJS controller method that redirects users to different URLs based on a query parameter type. If type is 'admin', redirect to '/admin/dashboard' with status 302; if 'user', redirect to '/user/home' with status 301; otherwise, redirect to '/' with status 302. Which code snippet correctly implements this?

hard

A. async redirect(@Query('type') type: string, @Res() res) {
if (type === 'admin') {
return res.redirect('/admin/dashboard');
} else if (type === 'user') {
return res.redirect(301, '/user/home');
} else {
return res.redirect('/');
}
}

B. async redirect(@Query('type') type: string, @Res() res) {
if (type === 'admin') {
res.redirect(302, '/admin/dashboard');
} else if (type === 'user') {
res.redirect('/user/home');
} else {
res.redirect(302, '/');
}
return 'Redirected';
}

C. async redirect(@Query('type') type: string, @Res() res) {
if (type === 'admin') {
return res.redirect(302, '/admin/dashboard');
} else if (type === 'user') {
return res.redirect('/user/home');
} else {
return res.redirect(302, '/');
}
}

D. async redirect(@Query('type') type: string, @Res() res) {
if (type === 'admin') {
res.redirect('/admin/dashboard');
} else if (type === 'user') {
res.redirect(301, '/user/home');
} else {
res.redirect('/');
}
}

Solution

1. Step 1: Check correct usage of res.redirect()

   Calling res.redirect() with URL only defaults to 302 status. To specify status, pass it as first argument. The method sends response immediately, so no return is needed.

2. Step 2: Analyze each option

   async redirect(@Query('type') type: string, @Res() res) { if (type === 'admin') { return res.redirect('/admin/dashboard'); } else if (type === 'user') { return res.redirect(301, '/user/home'); } else { return res.redirect('/'); } } incorrectly uses return res.redirect(), which can cause errors. async redirect(@Query('type') type: string, @Res() res) { if (type === 'admin') { res.redirect(302, '/admin/dashboard'); } else if (type === 'user') { res.redirect('/user/home'); } else { res.redirect(302, '/'); } return 'Redirected'; } returns a string after redirect, causing errors. async redirect(@Query('type') type: string, @Res() res) { if (type === 'admin') { return res.redirect(302, '/admin/dashboard'); } else if (type === 'user') { return res.redirect('/user/home'); } else { return res.redirect(302, '/'); } } mixes return and missing status codes. async redirect(@Query('type') type: string, @Res() res) { if (type === 'admin') { res.redirect('/admin/dashboard'); } else if (type === 'user') { res.redirect(301, '/user/home'); } else { res.redirect('/'); } } calls res.redirect() properly without return and uses correct status codes.

3. Final Answer:

   The code that calls res.redirect() properly without return and with correct status codes -> Option D

4. Quick Check:

   Call res.redirect() without return, specify status if needed [OK]

Hint: Call res.redirect() without return; specify status as first argument [OK]

Common Mistakes:

• Returning after res.redirect() causing errors
• Not specifying status code correctly
• Returning strings after sending response