NestJs Questions

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Score: 🔥 117

Beginner

Took 6 minutes

Programming Framework

NestJs

90%

Questions Attempted

10 / 10

Correct Answers

Incorrect Answers

Points Earned

🔥 9

Question 1

How do you access query parameters in a NestJS controller method?

Using @Body()
Using @Param()
Using @Query()
Using @Headers()

Explanation:

The @Query() decorator provides access to query parameters within a controller method. It allows you to retrieve values passed as key-value pairs in the URL's query string.

Question 2

What is the purpose of the return statement in a NestJS controller method?

To define the route path
To specify middleware for the route
To send the response to the client
To handle errors within the route

Explanation:

The value returned from a NestJS controller method forms the response sent back to the client. This can be a simple object, a string, or more complex data.

Question 3

Which decorator is used to define a custom exception filter in NestJS?

@Injectable()
@Catch()
@Controller()
@Module()

Explanation:

The @Catch() decorator is specifically designed to mark a class as an exception filter, allowing it to handle specific exception types.

Question 4

What is the role of the 'HttpException' class in NestJS exception handling?

It's a base class for creating custom exceptions with HTTP status codes.
It's a decorator for marking methods that handle HTTP exceptions.
It's a module for configuring global exception handling.
It's an interface for defining the structure of exception objects.

Explanation:

The HttpException class provides a convenient way to create custom exceptions that carry appropriate HTTP status codes, making it easy to send meaningful error responses to clients.

Question 5

What is the primary function of middleware in NestJS?

To handle database operations.
To define API routes.
To intercept and modify incoming requests and outgoing responses.
To render dynamic views on the server.

Explanation:

Middleware in NestJS acts as a bridge between incoming requests and the route handlers. It allows you to perform tasks like logging, authentication, or data transformation before the request reaches the controller.

Question 6

Which decorator allows you to access route parameters in NestJS?

@Body()
@Query()
@Param()
@Req()

Explanation:

The @Param() decorator is used to inject route parameters into controller methods. It allows you to access values from the URL path defined in your route.

Question 7

What is the purpose of the @Body() decorator?

Accesses route parameters
Accesses query parameters
Accesses the entire request body
Accesses the request headers

Explanation:

The @Body() decorator is used to access the entire request body sent by the client. It allows you to retrieve data sent in formats like JSON or form data.

Question 8

What is the primary purpose of using Interceptors in NestJS?

To handle database queries.
To define routes for API endpoints.
To intercept and modify incoming requests or outgoing responses.
To create reusable UI components.

Explanation:

Interceptors in NestJS provide a mechanism to intercept and potentially modify incoming requests before they reach route handlers or outgoing responses before they are sent back to the client.

Question 9

What is a common use case for middleware in NestJS?

Generating database queries.
Rendering HTML templates.
Implementing authentication and authorization logic.
Defining API endpoints.

Explanation:

One of the most common use cases for middleware in NestJS is to handle authentication and authorization. Middleware provides a centralized location to verify user credentials, check permissions, and control access to protected routes.

Question 10

What is the role of the 'main.ts' file in a NestJS project?

Defines the application's database schema and models
Contains unit tests for the application's logic
Creates and configures the NestJS application instance
Stores environment variables and configuration settings

Explanation:

The main.ts file is the entry point of your NestJS application. It bootstraps the NestJS application, often setting up the listening port and other core configurations.