Tags | js node backend |
Most people are introduced to JavaScript in the context of a web browser. JS adds smarts to HTML and CSS.
JS is a proper programming language so it can do a whole lot more than making a web page clever. It doesn’t need to interact with a website to work. You can use it on the “back-end”. It can be used to interact with filesystems and databases and all sorts of other things.
When JS is running on the backend it’s usually referred to as Node. Node is a “runtime environment” that can execute JS code.
Here are instructions on how to install node: https://nodejs.org/en/download/
Try typing this into a terminal:
node
Now type
var greeting = "hello world";
console.log(greeting);
So you see you can execute JavaScript code right there in your terminal and it just works.
Now save the HelloWorld code above to a file named hello.js
. You can execute this whenever you want to by saying node hello.js
in a terminal. Or rather node /path/to/hello.js
if you are in a different location.
There are a few different package managers. The two main ones are npm and yarn. In this course, you’ll be using npm.
If you know how to use npm then using a different package manager will be pretty easy.
https://docs.npmjs.com/about-npm/
Install npm if you need to. Then follow the steps below:
npm_demo
npm init
. Npm will ask you a bunch of questions. You can just say yes to everything.npm install jasmine
. Jasmine is a tool used for testing your js code. When you type in this command then npm will download and install jasmine, and update a few other files in the directory. Take a look around your directory again.Super Important you’ll notice that npm creates a directory called node_modules
. This is where the downloaded code gets saved. You’ll see jasmine in there. Make sure you always gitignore your node_modules directory