Hybrid applications in NestJS - Mini Project: Build & Apply

Building a Hybrid Application with NestJS

📖 Scenario: You are creating a simple NestJS application that can run both as a REST API server and as a GraphQL server. This hybrid setup allows your app to serve different types of clients easily.

🎯 Goal: Build a NestJS hybrid application that sets up both REST and GraphQL modules and starts the server with both capabilities.

📋 What You'll Learn

Create a NestJS application instance

Configure a REST controller

Configure a GraphQL module

Use the app.select() method to create a hybrid app

Start the application listening on port 3000

💡 Why This Matters

🌍 Real World

Hybrid applications let you serve different client needs from one backend, like mobile apps using REST and web apps using GraphQL.

💼 Career

Understanding hybrid apps with NestJS is useful for backend developers building flexible APIs that support multiple protocols.

1

Create the NestJS application instance

Write code to create a NestJS application instance called app using NestFactory.create(AppModule).

NestJS

// Your code here to create the NestJS app instance

Need a hint?

Use NestFactory.create(AppModule) to create the app instance.

2

Add a configuration variable for the port

Add a constant variable called port and set it to 3000.

NestJS

import { NestFactory } from '@nestjs/core';
import { AppModule } from './app.module';

async function bootstrap() {
  const app = await NestFactory.create(AppModule);
  // Define the port number
  const port = 3000;
}

bootstrap();

Need a hint?

Use const port = 3000; inside the bootstrap function.

3

Create the hybrid application with REST and GraphQL modules

Use app.select() to select AppModule and create a hybrid app instance called hybridApp.

NestJS

import { NestFactory } from '@nestjs/core';
import { AppModule } from './app.module';

async function bootstrap() {
  const app = await NestFactory.create(AppModule);
  const port = 3000;
  // Create hybrid app instance
}

bootstrap();

Need a hint?

Use const hybridApp = app.select(AppModule); to create the hybrid app.

4

Start the hybrid application listening on the port

Call hybridApp.listen(port) to start the server on port 3000.

NestJS

import { NestFactory } from '@nestjs/core';
import { AppModule } from './app.module';

async function bootstrap() {
  const app = await NestFactory.create(AppModule);
  const port = 3000;
  const hybridApp = app.select(AppModule);
  // Start the server
}

bootstrap();

Need a hint?

Use await hybridApp.listen(port); to start the server.