Node.js : Day 2

Webserver in node.js, Routing in node.js, NPM and Prettier set-up

How to create web server in Node.js?

→ by using http module.

Step 1. Import http module

const http = require("http");

Step 2. Create a Server

const server = http.createServer((req,res)=>{
res.end("Hello from the server");
)

Step 3. Start a Server and listen to request

server.listen(3000, "127.0.0.1", ()=>{
    console.log("Server is running on Port 3000");
})

/*
  PORT is 3000
  localhost ip is 127.0.0.1
*/

Step 4. Requesting to server by using browser

go to any browser and type “http://127.0.0.1:3000”

Routing in Node.js

How can we check which url user is requesting:

Routing and How to send response header:

Checking for header in browser:

Intoduction to npm:

npm is actually node package manager, It is used for installing, updating, and managing dependencies in a project.

To initialize a project:

npm init

Two main types of dependencies:

1. Dependencies: These are libraries or packages that your project needs to run. These are required during production.

npm i package_name

2. Dev Dependencies:

• These are packages that are only needed during development (e.g., for testing, building, or compiling code). They are not required for the application to run in production.

npm i package_name --dev

To uninstall the packages:

npm uninstall package_name

node_modules contains all the dependency of project.

Q. What is the meaning of Tilde and Caret in package.json:

~ (Tilde): Allows patch updates but not minor or major updates.

• Example: "~4.17.1" → 4.17.x but not 4.18.x or 5.x.x.

^ (Caret): Allows minor and patch updates but not major updates.

• Example: "^4.17.1" → 4.x.x but not 5.x.x.

dotenv. eslint, image preview, prettier — code formatter

How to configure prettier?

Steps to configure Prettier using the .prettierrc file:

1. Install Prettier

First, you need to install Prettier in your project.

npm install --save-dev prettier

2. Create a .prettierrc Configuration File

• The .prettierrc file allows you to specify various settings to control how Prettier formats your code. You can create this file in the root of your project.
• The .prettierrc file can be in JSON format, YAML format, or JavaScript format. The most common and simplest is the JSON format.

1. Example of a .prettierrc file (JSON format):

{   "semi": true,   
    "singleQuote": true,  
    "trailingComma": "all",   
    "tabWidth": 2,   
    "printWidth": 80 
}

• semi: If set to true, Prettier will add a semicolon at the end of every statement. If set to false, no semicolons will be added.
• singleQuote: If set to true, Prettier will use single quotes (') instead of double quotes (") for strings.
• trailingComma: This controls when trailing commas are added. It can have the following values:
• "none": No trailing commas (default).
• "es5": Adds trailing commas where valid in ES5 (like in arrays and objects).
• "all": Adds trailing commas everywhere possible, including function parameters.
• tabWidth: Defines the number of spaces per indentation level (default is 2).
• printWidth: Specifies the line length where Prettier will wrap the code. For example, a value of 80 means the line will wrap after 80 characters.

there are other’s configuration options too, you can go through this document:

Options · Prettier

thanks…