NestJS NestJS 4

Question 1

What is the purpose of the @Module() decorator's 'exports' array in NestJS?

Accepted Answer

To make providers available to other modules that import this module

Answer

The exports array specifies which providers from the current module can be used by other modules that import it.

Question 2

How do you make a NestJS module available globally without importing it in every module?

Accepted Answer

Use the @Global() decorator on the module

Answer

The @Global() decorator marks a module as global-scope so its exported providers are available throughout the application without needing explicit imports.

Question 3

What is a Dynamic Module in NestJS?

Accepted Answer

A module that returns a DynamicModule object from a static method, allowing configuration at import time

Answer

Dynamic modules expose a static method (like register() or forRoot()) that returns a DynamicModule object, enabling customizable module configuration when imported.

Question 4

Which NestJS feature allows deferring a provider's initialization until it's first requested?

Accepted Answer

Asynchronous providers using useFactory with async/await

Answer

Asynchronous providers using useFactory with async/await defer initialization until the factory resolves, useful for database connections and external service setup.

Question 5

In NestJS, what is the purpose of the forwardRef() utility?

Accepted Answer

To resolve circular dependencies between modules or providers

Answer

forwardRef() is used to resolve circular dependencies by wrapping the class reference in a function, allowing NestJS to defer the reference resolution.

NestJS Practice Test

NestJS Practice Test

NestJS NestJS 4