Unleashing the Power of NestJS and Serverless Framework: A Comprehensive Guide

As the digital world evolves, the demands on software development to deliver scalable, efficient, and fast services have never been higher. Enter the realm of NestJS and Serverless Framework, a combination that provides developers with a robust toolkit for building serverless applications with ease and precision. This article aims to guide you through the essentials of NestJS and Serverless Framework, showcasing how to leverage these technologies to build scalable applications. Whether you are a beginner or an experienced developer, this step-by-step tutorial will equip you with the knowledge to harness the full potential of NestJS and Serverless Framework in your projects.

Why NestJS with Serverless?

NestJS is a progressive Node.js framework for building efficient, reliable, and scalable server-side applications. It uses TypeScript by default (though also supports JavaScript) and is heavily inspired by Angular in terms of its architecture and design patterns. This makes it an excellent choice for developers looking for an opinionated framework that promotes best practices and code organization.

Serverless Framework, on the other hand, simplifies deploying your applications to cloud providers like AWS, Azure, and Google Cloud Platform without worrying about the underlying infrastructure. It allows developers to focus on writing code rather than managing servers, thereby significantly reducing development time and costs.

Combining NestJS’s structured approach to building applications with the Serverless Framework’s deployment capabilities creates a powerful duo for developing and deploying scalable, cloud-native applications.

Prerequisites

Before diving in, ensure you have the following installed:

• Node.js (LTS version)
• npm or yarn (as your package manager)
• Serverless Framework: Install globally via npm npm install -g serverless
• An AWS account set up with the AWS CLI configured on your machine.

Step 1: Setting Up Your NestJS Project

1. Create a new NestJS project: Run npx @nestjs/cli new serverless-nestjs-project in your terminal.
2. Navigate to your project directory: cd serverless-nestjs-project

Step 2: Integrating Serverless Framework

1. Install the Serverless Framework: If you haven’t already, install it globally via npm: npm install -g serverless.
2. Add the Serverless Framework plugin: In your project root, run npm install --save-dev serverless-offline serverless-plugin-typescript.
3. Configure Serverless: Create a serverless.yml file in your project root with the following basic configuration:

service: serverless-nestjs-project

provider:
  name: aws
  runtime: nodejs14.x
  stage: dev
  region: us-east-1
functions:
  app:
    handler: dist/lambda.handler
    events:
      - http:
          path: "{proxy+}"
          method: any

1. Modify your NestJS application for Serverless: Create a new file named lambda.ts in the src folder. This file will export your NestJS application as an AWS Lambda compatible handler.

import { NestFactory } from '@nestjs/core';
import { AppModule } from './app.module';
import { ExpressAdapter } from '@nestjs/platform-express';
import * as express from 'express';
import { Server } from 'http';

const bootstrapServer = async (): Promise<Server> => {
  const expressApp = express();
  const app = await NestFactory.create(
    AppModule,
    new ExpressAdapter(expressApp),
  );
  await app.init();
  return expressApp;
};
export const handler = bootstrapServer();

Step 3: Deploying Your Application

1. Deploy to AWS: Run serverless deploy in your terminal. This command compiles your TypeScript application, packages it, and deploys it to AWS Lambda under the configuration specified in your serverless.yml.
2. Testing Your Deployment: After deployment, Serverless Framework outputs the URLs to access your Lambda function. You can test these endpoints using tools like Postman or directly from your browser.

Best Practices and Tips

• Local Development: Use the serverless-offline plugin for local development to simulate AWS Lambda and API Gateway locally. Run serverless offline to start a local server.
• Environment Variables: Use the serverless-dotenv-plugin to manage your environment variables securely.
• Monitoring and Logging: Leverage cloud provider tools (e.g., AWS CloudWatch) or third-party services to monitor and log your application’s performance and errors.

Conclusion

Merging NestJS’s powerful architecture with the Serverless Framework’s deployment capabilities offers a streamlined path for developing and deploying scalable, serverless applications. This guide has walked you through the basics, but the journey doesn’t end here. Explore further, experiment with your projects, and leverage the vast ecosystem of plugins and modules available to both NestJS and the Serverless Framework. Happy coding!