NestJS NestJS Architecture & Design Patterns

Question 1

Which NestJS decorator is used to define a class as a module?

Accepted Answer

@Module()

Answer

The @Module() decorator marks a class as a NestJS module that organizes related providers, controllers, and imports.

Question 2

What is the purpose of the `providers` array in the @Module() decorator?

Accepted Answer

To register services that can be injected within the module

Answer

The `providers` array registers services (and other injectables) with the NestJS IoC container so they can be injected within that module.

Question 3

Which pattern does NestJS primarily use for organizing application logic?

Accepted Answer

Modular architecture with DI

Answer

NestJS uses a modular architecture combined with dependency injection (DI) to organize and decouple application components.

Question 4

What does the `exports` array in @Module() control?

Accepted Answer

Which providers can be used by other modules

Answer

The `exports` array specifies which providers from the current module are available for other modules that import it.

Question 5

Which NestJS concept allows a module to be shared across the entire application without re-importing?

Accepted Answer

Global Module

Answer

A Global Module decorated with @Global() makes its exported providers available everywhere without requiring explicit imports.

NestJS Practice Test