 folder as the location where you'll place your application's source code. This arrangement adheres to Nest.js's modular architecture, promoting better organization and separation of concerns within your application. 

 file serves as the entry point of your Nest.js application. This file is responsible for bootstrapping the application, utilizing Nest.js's core function 

 to create an instance of your Nest application.

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

async function bootstrap() {
   const app = await NestFactory.create(AppModule);
   await app.listen(3000);
}
bootstrap();

 file serves as the entry point for the application and employs the core function 

 to instantiate a Nest application. In Nest.js, 

 is pivotal for bootstrapping the application, setting up the dependency injection system, and initializing modules. This follows the Nest.js principle of modular development and centralized configuration.

---
title: Project Directory Structure Explanation
description: Project directory structure
role: "INTRODUCTION"
privateVideoUrl: https://fullstack.wistia.com/medias/inrx67518j
isPublicLesson: true
---

## Project Directory structure

Nest.js designates the `src` folder as the location where you'll place your application's source code. This arrangement adheres to Nest.js's modular architecture, promoting better organization and separation of concerns within your application. 

Within the `src` folder, the `main.ts` file serves as the entry point of your Nest.js application. This file is responsible for bootstrapping the application, utilizing Nest.js's core function `NestFactory` to create an instance of your Nest application.

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

async function bootstrap() {
   const app = await NestFactory.create(AppModule);
   await app.listen(3000);
}
bootstrap();
```

The `main.ts` file serves as the entry point for the application and employs the core function `NestFactory` to instantiate a Nest application. In Nest.js, `NestFactory` is pivotal for bootstrapping the application, setting up the dependency injection system, and initializing modules. This follows the Nest.js principle of modular development and centralized configuration.

-   `app.controller.ts`: This is a basic controller file containing a single route. Controllers in Nest.js are responsible for request handling and response sending, acting as a gateway between client and server.
-   `app.controller.spec.ts`: This file contains unit tests for the controller, adhering to the Nest.js focus on test-driven development (TDD).
-   `app.module.ts`: This is the root module of the application, which imports other modules and providers. Nest.js modules act as organizational units and follow the Single Responsibility Principle.
-   `app.service.ts`: A basic service file with a single method. In Nest.js, services encapsulate business logic and can be injected into controllers, promoting Dependency Injection and the Separation of Concerns.
-   `nest-cli.json`: Utilized for Nest.js-specific configurations, this file allows customization of compiler options, assets, and other settings.
-   `.prettierrc`: This file is used for configuring Prettier, aiding in code formatting and style consistency within the Nest.js project.
-   `tsconfig.json`: This configuration file is for TypeScript and determines how the TypeScript compiler will behave. This aligns with Nest.js's use of TypeScript for strong typing and better code quality.


Haider Malik

Project Directory Structure Explanation

Let's walk through the project directory structure.

We will place our source code inside the source directory.

We will have controller, module, service and the main file.

We have only one method inside the controller.

We will place all the routes inside the controller file.

And we have only one test, I'll teach you how to do testing, how to write unit

By default, NestJS has registered app controller and the app service.

We have only single method which is getHello, m returning the string.

We will place all the data bits related to operations, thread methods inside

And we have controller, we have only single test.

I'll teach you how to write unit test, how to do unit testing.

This CLI is used to configure CLI Nest project and TS config is used for

It is used for formatting the source code.

We have already implemented it here R2 file.

And inside the packages, package.json file, we have Nest common package, NestJS

in told you it is built on the top of expressJS.

They have the express platform, this is express package, express framework

We are using RXJS and reflecting all of these all the dependencies, ES plain,

more type, just and the typing of the extra.

We will place all the tests inside the test directory.

Nest is using this directory to compile writes that into JavaScript file.

This is our entry file, this bootstrap function will create the instance of

to create the instance of NestJS application.

We got to provide the root module, which is app module.

And the nest package is a class, we have the method, which is get, it's an

And we have provided the port and finally we call the bootstrap method.

If you want to dig into the nest factory, what it is doing and how it is

the class or instantiating the NestJS application, you can find the NestJS

Here we have installed the port package inside the package.json file.

You can see we have the port package and inside the packages, I have to look

I got the Nest factory, this is the class, Nest factory static.

This is the static class, they have made the static, we don't need to instant

They just directly call the create method and you can see that we have the

Inside the Nest factory, they are registering the server configuration, doing

local configuration, initialize the module, HTTP server stuff.

Here they are instantiating the instance of actually creating the instance of

by providing the HTTP server configuration and app option.

This method is used to instantiate the microservice, this method is used to

I just want to show you the Nest factory class.

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