> ## Documentation Index
> Fetch the complete documentation index at: https://notes.kodekloud.com/llms.txt
> Use this file to discover all available pages before exploring further.
# NodeJS Application Overview
> This article provides an overview of setting up a minimal Node.js application and preparing for a custom GitHub Action workflow.
Node.js is a powerful, open-source JavaScript runtime built on Chrome’s V8 engine. It enables you to execute JavaScript on the server side, allowing you to use a single language across your entire stack. In this guide, we’ll explore the basics of a minimal Node.js project and prepare for creating a custom GitHub Action workflow.
Node.js runs on Windows, macOS, and most Linux distributions. Ensure you’re using a supported version for compatibility.
## Prerequisites
Verify your installed versions:
```bash theme={null}
$ node -v
v18.16.0
$ npm -v
9.8.1
```
> You should have Node.js (v14+) and npm installed.\
> If not, download them from [Node.js Official Site][nodejs].
## Project Structure
A minimal Node.js project typically includes these elements:
| Item | Description |
| -------------- | --------------------------------------------------------------------- |
| package.json | Metadata: name, version, dependencies, and custom scripts. |
| node\_modules/ | Automatically generated by `npm install`; contains all your packages. |
| index.js | Entry point for your application—your core business logic. |
| test.js | Unit tests and integration tests for your functions and endpoints. |
## Installing Dependencies
Install all required libraries listed in `package.json`:
```bash theme={null}
npm install
```
This command reads `package.json` and populates the `node_modules/` directory with every dependency.
## Running Tests
Execute your tests as defined in the `test` script of `package.json`:
```bash theme={null}
npm test
```
A successful run will output results and confirm that all test cases pass.
## Starting the Application
Launch the server using the `start` script:
```bash theme={null}
npm start
```
By default, the app listens on port 3000. Verify the endpoint:
```bash theme={null}
curl http://localhost:3000/hello
# Expected output: Hello World!
```
If port 3000 is in use, modify the port in `index.js` or set the `PORT` environment variable before starting.
***
With your Node.js application up and running, you’re now ready to integrate it into a custom GitHub Action. In the next section, we’ll build a workflow file that automates tests and deployment.
## Links and References
* [Node.js Official Site][nodejs]
* [npm Documentation][npm]
* [GitHub Actions][gh-actions]
[nodejs]: https://nodejs.org/
[npm]: https://docs.npmjs.com/
[gh-actions]: https://docs.github.com/actions/overview