Requirements to run Node Js

Question : What are the necessary software requirements to run Node.js Applications successfully?

• To build a web development project using Node.js, we need to set up the right software tools and dependencies. These are –
  • Install Node.js & NPM
    • First, download and install Node.js from their site. Node.js is required to run JavaScript as the major code on the backend, and NPM (Node Package Manager) helps install other dependencies. NPM is already included and installed with Node.js. The LTS (Long-Term Support) version is installed for stability.
    • (To check the successful installation, open the VS code Terminal/Command Prompt and run/Verify installation:

If both commands return specific version numbers, Node.js and NPM are successfully installed.)

• • Install a Code Editor (VS Code Recommended)
    • Download VS code https://code.visualstudio.com/ and install a suitable Node.js Extension Pack for better support.

  • Create and Initialize a Node.js Project

    • First of all, we create a project folder in a system drive (say E drive) or folder (such as NodeProject)

• • • Now, initialize the Node.js project by typing the command at the VS code terminal –

E:\NodeProject> npm init -y  (press enter)

This command creates a package.json file interactively that manages our project dependencies.

• • Choose and Install a Web Framework (Express.js Recommended)
    • Express.js is the most popular web framework for Node.js/backend development. Install the Express web framework properly by typing the command at VS Code terminal –

• • Choose a front-end technology to create UI

    • We can use HTML, CSS, JavaScript, or a frontend framework for creating frontend UI like:

      • React.js (npx create-react-app my-app)
      • Vue.js (npm install -g @vue/cli)
      • Angular (npm install -g @angular/cli)
  • Choose, Install, and Connect to a Database

• • • • Use MongoDB (NoSQL) → Install mongoose:
        • npm install mongoose (on VS code terminal)
      • Use MySQL (SQL) → Install mysql2 directly from the terminal or XAMPP.
        • npm install mysql2  (on VS code terminal) but better is or
        • Install XAMPP : Download and install XAMPP from https://www.apachefriends.org/, start MySQL from the XAMPP Control Panel, open the browser and type http://localhost/phpmyadmin/, and finally create a database and the required tables.
      • Use PostgreSQL (SQL) →
  • Install Additional Tools (Optional)
    •  Install and run Nodemon (To auto-restart server dynamically on browser when code changes):

• • • dotenv (for Managing environment variables):

E:\NodeProject>npm install dotenv (press enter)

• • • CORS (Enable cross-origin requests/Enable API requests from other domains):

E:\NodeProject>npm install cors (press enter)

Ques. : What are the necessary steps and structure to develop and run Node.js Applications?

A typical Project Structure are -

Create the NodeProject folder that may include following folder and files for different purposes using VS Code editor:

(A.) [Simple and Easy Method/Structure - For small projects]
(Source Code Details)
NodeProject/
│── views/
│   ├── user_registration.ejs
│── public/
│   ├── style.css and interactive.js
│── server.js
│── package.json

Here, 
  (i) views folder includes one or more frontend UI forms in the form of ejs files.
  (ii) public folder includes one or more css and js files.
  (iii) server.js file includes database(such as MySql) connectivity codes, form submission codes, back end codes, server sets up codes etc.
  (iv) The package.json file is the heart of any Node.js project. 
 - It plays a crucial role in defining the project’s metadata, dependencies, and scripts. 
 - In other words, it describes your project metadata (project name, version, description, license, author, etc.), manages your dependencies (Lists npm packages required for production (dependencies) and development (devDependencies) i.e., packages your app needs), defines scripts using custom commands you can run via npm run (like start, test, build, etc.), acts as entry point and tells Node which file to start (main) and helps share and install your project consistently. 
 - It ensures project consistency across systems, makes your project portable and installable, helps with automation through scripts, required for publishing packages to npm registry.
 - It is necessary for running, building, and deploying Node.js apps.

Package.json file:
{
  "name": "my-node-app",
  "version": "1.0.0",
  "description": "A simple Node.js app",
  "main": "server.js",
  "scripts": {
    "start": "node server.js",
    "dev": "nodemon server.js"
  },
  "dependencies": {
    "express": "^4.18.2",
    "mysql2": "^3.2.0"
  },
  "author": "Your Name",
  "license": "ISC"
}

(v) node_modules is an automatic created directory where Node.js stores all dependencies (packages/libraries) for our app needs, which are installed using npm (Node Package Manager) or yarn. When you write require('express'), Node looks in node_modules/express. The .bin/ folder contains executable files (e.g., CLI tools).

NB : To run the complete Node.js application through the this structure via terminal/command prompt - node server.js (press enter)


(B.) [Also, Simple and Organised Method/Structure - Better For large projects]

NodeProject/
│── views/
│   ├── user_registration.ejs
│── public/
├   ├──style.css and interactive.js
│── routes/
│   ├── auth.js
│── config/
│   ├── db.js
│── app.js
│── package.json

Here,
  (i) routes folder contains files where we define our application routes — which URLs (endpoints) our server should respond to and how. It organizes routing logic.It keeps route handling out of the main app.js.It is easier to scale and maintain.
  (ii) config folder stores configuration-related files—like database connection setup, environment variables, or third-party API keys. It avoids duplication across multiple files. It centralizes config settings. 
  (iii) app.js file is considered as the central controller that initializes or  starts by importing necessary modules and initializing an Express app; we define middleware here like: body-parser to handle form data, express.static for serving static files, express-session for session management; View Engine Setup when we're using EJS, Pug, or Handlebars for templating, app.js sets that up; connects to the database by importing the file; mounts routes i.e. it connects all our route files, and starts the server by listening on a port so your app is available in the browser.

NB : To run the complete Node.js application through the this structure via terminal/command prompt - node app.js (press enter)