truongductri01 / nodejs_tutorial

NODE.JS

Node.js makes JavaScript run outside of the browser (no need for HTML to see the result returned from the script)

Neither a framework or programming language

SetUp

1. Install node.js: here
2. Check if it is installed correctly. Type the code in the terminal
   node --version
npm --version

Run Code using Node

Create a javascript file, "app.js" for example Inside the app.js, put in the example code: console.log("Hello World")

Then just need to run node app in the terminal

Difference from Node.js and normal Browser Js

Browser JS:

1. Before the code run, the window object is already created
2. The code can access any element shown on the window using document.querySelector(<classname>)
3. Every thing is created on top of that existed window object

Node JS:

1. Module based: everything only exist within the code file
2. To use a module, it is needed to be exported and imported
   • Export a function call sayName:
     module.exports = sayName;
   • Import the function (the path to the file may change based on your code's order):
     const sayName = require("./sayName")

Modules covered in the code

1. Path module: provides a lot of very useful functionality to access and interact with the file system. Path module's documentation
2. url module
3. fs module
4. http module

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Should init every project with npm

Run code npm init in the terminal

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Dependecy to install

1. Nodemon: a live server for node.js nodemon app.js
   So every time the app.js file is changed, nodemon will automatically re-run