Chapter 1 - Initialize the project with NestJS¶

In this chapter, you will create a new NestJS project with the NestJS CLI.

You will then be able to start the application to see if it runs correctly.

Steps¶

Install NestJS CLI¶

The NestJS CLI allows to create and manage NestJS projects.

1

npm install --global @nestjs/cli

Create a NestJS project¶

Create a NestJS project in the local directory.

1

nest new --package-manager npm --strict --skip-git .

NestJS should create a project that looks like this in your working directory.

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20

.
├── node_modules # (1)!
│   └─── ...
├── src # (2)!
│   ├── app.controller.spec.ts
│   ├── app.controller.ts
│   ├── app.module.ts
│   ├── app.service.ts
│   └── main.ts
├── test
│   ├── app.e2e-spec.ts
│   └── jest-e2e.json
├── .eslintrc.js
├── .prettierrc
├── README.md
├── nest-cli.json
├── package-lock.json
├── package.json # (3)!
├── tsconfig.build.json
└── tsconfig.json

1. The node_modules directory contains all the dependencies needed to run your project.
2. The src directory contains all the source code of your project.
3. The package-lock.json file is the main file of your project. It defines the available scripts, the dependencies and some information regarding your project.

Start the NestJS application¶

1

npm run start:dev

The output of the command should look similar to this.

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12

> create-a-media-player-application@0.0.1 start:dev
> nest start --watch

[12:02:22 PM] Starting compilation in watch mode...

[12:02:32 PM] Found 0 errors. Watching for file changes.

[Nest] 14334  - 01/27/2023, 12:02:38 PM     LOG [NestFactory] Starting Nest application...
[Nest] 14334  - 01/27/2023, 12:02:38 PM     LOG [InstanceLoader] AppModule dependencies initialized +43ms
[Nest] 14334  - 01/27/2023, 12:02:38 PM     LOG [RoutesResolver] AppController {/}: +23ms
[Nest] 14334  - 01/27/2023, 12:02:38 PM     LOG [RouterExplorer] Mapped {/, GET} route +5ms
[Nest] 14334  - 01/27/2023, 12:02:38 PM     LOG [NestApplication] Nest application successfully started +4ms

Check the results¶

You can now access your NestJS application on http://localhost:3000. You should see the message Hello World!.

To stop your NestJS application, press Ctrl+C in your terminal.

Summary¶

Congrats! You have a default NestJS application running! You are now able to create NestJS projects and start/stop NestJS applications.

Go further¶

Are you able to change the message to Hello BeeScreens!? Expand the next component to see the answer!

1
2
3
4
5

// ...
getHello(): string {
	return 'Hello World!';
}
// ...

1
2
3
4
5

// ...
getHello(): string {
	return 'Hello BeeScreens!';
}
// ...