Environment-based configuration in NestJS - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to import the ConfigModule in a NestJS module.

NestJS

import { Module } from '@nestjs/common';
import { ConfigModule } from '@nestjs/config';

@Module({
  imports: [ConfigModule.[1]()],
})
export class AppModule {}

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

AforRoot

Bregister

Cinitialize

Dsetup

Attempts:

3 left

💡 Hint

Common Mistakes

Using a method name that does not exist on ConfigModule.

Forgetting to call the method as a function.

The ConfigModule.forRoot() method loads environment variables and makes them available throughout the app.

2fill in blank

medium

Complete the code to inject ConfigService into a service constructor.

NestJS

import { Injectable } from '@nestjs/common';
import { ConfigService } from '@nestjs/config';

@Injectable()
export class AppService {
  constructor(private readonly [1]: ConfigService) {}
}

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Aconfig

BconfigSrv

CserviceConfig

DconfigService

Attempts:

3 left

💡 Hint

Common Mistakes

Using a generic or unclear variable name.

Not matching the injected type with the variable name.

The common convention is to name the injected ConfigService instance configService for clarity.

3fill in blank

hard

Fix the error in accessing an environment variable using ConfigService.

NestJS

const port = this.configService.[1]('PORT');

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AgetValue

Bget

Cfetch

Dretrieve

Attempts:

3 left

💡 Hint

Common Mistakes

Using non-existent methods like getValue or fetch.

Trying to access environment variables directly without ConfigService.

The correct method to get environment variables from ConfigService is get.

4fill in blank

hard

Fill in the blank to access an environment variable with a default value fallback.

NestJS

const dbHost = this.configService.[1]('DATABASE_HOST', 'localhost');

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

Aget

Bdefault

Cundefined

Dnull

Attempts:

3 left

💡 Hint

Common Mistakes

Using incorrect method names.

Trying to use keywords like undefined or null as default values incorrectly.

The get method accepts a second argument as a default value if the environment variable is not set.

5fill in blank

hard

Fill all three blanks to define a custom configuration loader function.

NestJS

import { [1] } from '@nestjs/config';

export const customConfig = registerAs([2], () => ({
  port: parseInt(process.env.[3] || '3000', 10),
}));

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AregisterAs

Bconfig

CPORT

DConfigModule

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing import names.

Using wrong environment variable names.

Not wrapping the config in a function.

registerAs is used to create a named configuration. The function returns an object with the port read from environment variable PORT.