As the complexity of my Node.js projects<\/a> increased, handling larger codebases got more difficult. The scaling process seemed sluggish and error-prone due to manual dependency wiring, fragmented structure, and a lack of robustness. Keeping clean, orderly codebases while incorporating additional libraries or services was difficult.<\/p>\n That\u2019s when I explored NestJS, and it transformed my approach. Its seamless integration of TypeScript<\/a> provided static typing and structure out of the box, making code easier to maintain. The well-organized architecture\u2014controllers, services, and modules\u2014immediately simplified my project structure.<\/p>\n The native dependency injection (DI) system was a game changer, handling external libraries and dependencies effortlessly. I no longer had to manually manage dependencies, allowing me to focus more on business logic. Unlike the manual setup required in Node.js, NestJS\u2019s opinionated, full MVC framework gave me the structure and confidence to build scalable, maintainable applications<\/a>. It became a modern, exciting alternative to my Node.js setups.<\/p>\n Server-side Node.js applications can be developed more efficiently and scalable with the help of the NestJS framework. Coders can develop programs in just JavaScript, but TypeScript is also fully supported and built-in. Because of its good library and tool integration, NestJS is a great option for both small projects and large business systems.<\/p>\n Developers using Node.js to create server side applications mostly work with Express.js, a simple web framework that offers the essential functionality for creating APIs<\/a>. However managing the codebase might get difficult as the application gets more complicated.<\/p>\n Let’s explore some of the fundamental concepts of NestJS:<\/p>\n Developing a backend in NestJS makes Node.js projects more streamlined, scalable, and easier to develop. GraphQL apps, microservices, and RESTful APIs can be quickly and simply created on a dependable and intuitive platform using NestJS. Its use of decorators, modular architecture, and integrated TypeScript support make it groundbreaking for server-side programming.<\/p>\n We are a digital technology services company providing innovative product engineering solutions to diverse industries across the globe. We design and build digital platforms<\/a> with Cloud, Data, and AI as the main pillars. Contact us<\/a> and start your transformative journey today.<\/p>\n","protected":false},"excerpt":{"rendered":" Introduction As the complexity of my Node.js projects increased, handling larger codebases got more difficult. The scaling process seemed sluggish and error-prone due to manual dependency wiring, fragmented structure, and a lack of robustness. Keeping clean, orderly codebases while incorporating additional libraries or services was difficult. That\u2019s when I explored NestJS, and it transformed my […]<\/p>\n","protected":false},"author":1400,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"iawp_total_views":15},"categories":[5876],"tags":[955,5042,55,5327,1177],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/posts\/66270"}],"collection":[{"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/users\/1400"}],"replies":[{"embeddable":true,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/comments?post=66270"}],"version-history":[{"count":39,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/posts\/66270\/revisions"}],"predecessor-version":[{"id":67628,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/posts\/66270\/revisions\/67628"}],"wp:attachment":[{"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/media?parent=66270"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/categories?post=66270"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.tothenew.com\/blog\/wp-json\/wp\/v2\/tags?post=66270"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}About NestJS<\/h3>\n
Read More: Implementing Role based Access Control in NestJS<\/a><\/h4>\n
Outstanding Features of NestJS<\/h3>\n
\n
Why Choose NestJS?<\/h3>\n
\n
\nExpress.js:<\/strong> Offers middleware and routing functions, however, developers have to manually reorganize the structure as the application expands.
\nNestJS:<\/strong> Comes with a built-in structure that fosters modularity. Large-scale applications benefit from improved maintainability as a result of the distinct division of responsibilities across controllers, services, and modules.<\/li>\n
\nExpress.js<\/strong> requires external packages for TypeScript support.
\nNestJS:<\/strong> Designed with TypeScript in mind, it has built-in support for type safety, interfaces, and decorators.<\/li>\n
\nExpress.js:<\/strong> No built-in DI system; developers need to implement their own or use external libraries.
\nNestJS:<\/strong> Provides a fully-fledged DI system, making testing easier and enabling better decoupling between different components of the application.<\/li>\n
\nExpress.js:<\/strong> Routing and middleware setup is done imperatively via methods like app.get(), app.post(), etc.
\nNestJS:<\/strong> Uses decorators like @Controller(), @Get(), @Post(), and @Put() for declarative routing, making the code more readable and aligned with modern JavaScript paradigms.<\/li>\n
\nExpress.js:<\/strong> Middleware handles logic between requests and responses.
\nNestJS:<\/strong> Introduces the concepts of interceptors (to transform response data), guards (for authorization checks), and pipes (for data validation and transformation), which offer more granular control over request\/response handling.<\/li>\n<\/ol>\nCore Concepts in NestJS<\/h3>\n
\n
\n<\/strong><\/strong>Modules are used to organize a NestJS application. Each module consists of controllers, providers, and other services organized logically within a set of code.<\/p>\nimport { Module } from '@nestjs\/common';\r\nimport { UsersController } from '.\/users.controller';\r\nimport { UsersService } from '.\/users.service';\r\n@Module({\r\n controllers: [UsersController],\r\n providers: [UsersService], \r\n})\r\nexport class UsersModule {}<\/pre>\n<\/li>\n
\n<\/strong>Controllers are responsible for handling incoming requests and returning responses to the client.<\/p>\nimport { Controller, Get } from '@nestjs\/common';\r\n@Controller('users')\r\nexport class UsersController {\r\n @Get()\r\n findAll(): string {\r\n return 'This action returns all users';\r\n }\r\n}<\/pre>\n<\/li>\n
\n<\/strong>Services handle the application’s business logic. They can be integrated into controllers or other services.<\/p>\nimport { Injectable } from '@nestjs\/common';\r\n@Injectable()\r\nexport class UsersService {\r\n getUsers(): string[] {\r\n return ['User1', 'User2', 'User3'];\r\n }\r\n}<\/pre>\n<\/li>\n
\n<\/strong>NestJS uses DI to provide services or other dependencies in controllers or services, reducing the coupling and making the application easier to maintain.<\/p>\nimport { Injectable } from '@nestjs\/common';\r\n@Injectable()\r\nexport class AppService {\r\n getHello(): string {\r\n return 'Hello World!';\r\n }\r\n}\r\n\r\nimport { Controller, Get } from '@nestjs\/common';\r\nimport { AppService } from '.\/app.service';\r\n@Controller()\r\nexport class AppController {\r\n constructor(private readonly appService: AppService) {}\r\n\r\n @Get() getHello(): string {\r\n return this.appService.getHello();\r\n }\r\n}<\/pre>\n<\/li>\n
\nMiddleware functions can be executed before a request reaches the route handler.<\/p>\nimport { Injectable, NestMiddleware } from '@nestjs\/common';\r\n\r\n@Injectable()\r\nexport class LoggerMiddleware implements NestMiddleware {\r\n use(req: Request, res: Response, next: Function) {\r\n console.log('Request...');\r\n next();\r\n }\r\n}<\/pre>\n<\/li>\n<\/ol>\nBuilding a Basic API<\/h3>\n
Step 1: Install NestJS CLI<\/strong><\/h5>\n
npm install -g @nestjs\/cli\r\nnest new my-nest-app<\/pre>\n
Step 2: Create a Users Module<\/strong><\/h5>\n
nest generate module users<\/pre>\n
Step 3: Create a Users Controller and Service<\/strong><\/h5>\n
nest generate controller users\r\nnest generate service users<\/pre>\n
Step 4: Implement CRUD in the Users Service<\/strong><\/h5>\n
import { Injectable } from '@nestjs\/common';\r\n@Injectable()\r\nexport class UsersService {\r\n private readonly users = [];\r\n create(user) {\r\n this.users.push(user);\r\n }\r\n findAll(): string[] {\r\n return this.users;\r\n }\r\n}<\/pre>\nStep 5: Handle HTTP Requests in the Users Controller<\/strong><\/h5>\n
import { Controller, Get, Post, Body } from '@nestjs\/common';\r\nimport { UsersService } from '.\/users.service';\r\n@Controller('users')\r\nexport class UsersController {\r\n constructor(private readonly usersService: UsersService) {}\r\n \r\n @Post()\r\n create(@Body() user: any) {\r\n this.usersService.create(user);\r\n }\r\n \r\n @Get()\r\n findAll(): string[] {\r\n return this.usersService.findAll();\r\n }\r\n}<\/pre>\nStep 6: Start the Application<\/strong><\/h5>\n
npm run start<\/pre>\n
Conclusion<\/h3>\n