Why configuration management matters in NestJS - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

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

NestJS

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

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

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

ADatabaseModule

BHttpModule

CAuthModule

DConfigModule

Attempts:

3 left

💡 Hint

Common Mistakes

Importing unrelated modules like HttpModule instead of ConfigModule.

Forgetting to import ConfigModule causes configuration to not load.

The ConfigModule is the NestJS module used for configuration management. Importing it allows the app to load environment variables and config files.

2fill in blank

medium

Complete the code to access a configuration value using ConfigService.

NestJS

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

@Injectable()
export class AppService {
  constructor(private readonly configService: ConfigService) {}

  getDatabaseHost(): string {
    return this.configService.[1]('DATABASE_HOST');
  }
}

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

Aget

Bset

Cload

Dfetch

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'set' instead of 'get' which causes errors.

Trying to access config values directly without ConfigService.

The get method of ConfigService retrieves the value of a configuration key.

3fill in blank

hard

Fix the error in the code to load environment variables from a custom path.

NestJS

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

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

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

Aenv.production

B'.env.production'

C'env.production'

D.env.production

Attempts:

3 left

💡 Hint

Common Mistakes

Omitting quotes causes syntax errors.

Using variable names without quotes instead of string paths.

The envFilePath option expects a string path with quotes, like '.env.production'.

4fill in blank

hard

Fill both blanks to create a configuration object with a default value and type safety.

NestJS

import { registerAs } from '@nestjs/config';

export default registerAs('database', () => ({
  host: process.env.DB_HOST || [1],
  port: Number(process.env.DB_PORT) || [2],
}));

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A'localhost'

B5432

C3306

D'127.0.0.1'

Attempts:

3 left

💡 Hint

Common Mistakes

Using port as a string instead of a number.

Forgetting to provide default values causing undefined errors.

Default host is usually 'localhost' and default port for PostgreSQL is 5432.

5fill in blank

hard

Fill all three blanks to create a typed configuration interface and use it in a service.

NestJS

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

interface AppConfig {
  apiKey: string;
  timeout: number;
}

@Injectable()
export class ApiService {
  constructor(private configService: ConfigService) {}

  getApiKey(): string {
    return this.configService.[1]<[2]>('API_KEY');
  }

  getTimeout(): number {
    return this.configService.get<[3]>('TIMEOUT');
  }
}

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

Aget

BAppConfig

Cnumber

Dfetch

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'fetch' instead of 'get' causes errors.

Not specifying generic types loses type safety.

The get method is used with a generic type to ensure type safety. AppConfig is the interface type, and number is the type for timeout.