Skip to main content

Welcome to Javascript

Node.js is an open source environment for Javascript.

And now that I've concluded the basics with Python, let's keep the ball rolling. I find that, even though Javascript looks a lot more complicated, I gel with it a bit easier, and I'm not sure why.

This is around the first 35 minutes of this tutorial here. I'm going to work through this and find some other resources. I've already found said resources and they look a little different in the code department than this, but it's mostly the same.

We make three things here;



  • Introduce ourselves
  • Make a small game
  • Establish classes and events





A node module is a javascript file.

My initial is appin.js, tutorial file is tut.js. You may want to open and follow along!

Javascript Separates your commands in a way instead of shoving them all into one file by calling to other files that are in the same path (./) and using const tut = require(‘./tut’)



I export classes and PI; It looks a bit ugly like this.

module.exports.PI = PI;
module.exports.Mathing = Mathing;

But we can also do it like this;

module.exports = {sum : sum, PI : PI, Mathing : Mathing}

Events module and events emitter

Event Emitters are what happens when an action - passing a control - takes place

Person is a class, and we put Mori and Hanlon in that class as two seperate objects. I modify the introduction for each name.

let Mori = new Person('Mori');
//Person extends eventemitter class
// Mori is an instance of the event emitter class
Mori.on('name',()=>{
console.log('Name is ' + Mori.name);
})
let Hanlon = new Person('Hanlon');
//Person extends eventemitter class
// Hanlon is an instance of the event emitter class
Hanlon.on('name',()=>{
console.log('And I am ' + Hanlon.name);


Finally, our little game. Variables num3 and num4 (I used num1 and num2 in tut.js, which appin.js pulled) are assigned a random number between 1 and 10 to add.

Q: How can we make the modifier random also?

else{
rl.setPrompt('No try again\n');
//the little new line bugger tripped me up
rl.prompt();
rl.on('line',(userInput)=>{ //this input will be tested
if(userInput.trim() == answer)
rl.close();
else {
rl.setPrompt(`${ userInput } is wrong \n
Try again. You can do it!\n`)
rl.prompt();
}
//it's a loop
})

Line 81 (See GitHub) says "This user input will be tested", so that random strings aren't seen as correct as opposed to the right answer.

If the user gets the question wrong, it loops until they get it correct ('answer'), then it stops the program, returning to the prompt.



Comments

Popular posts from this blog

Connecting IoT Devices to a Registration Server (Packet Tracer, Cisco)

In Packet Tracer, a demo software made by Cisco Systems. It certainly has changed a lot since 2016. It's almost an Olympic feat to even get started with it now, but it does look snazzy. This is for the new CCNA, that integrates, among other things, IoT and Automation, which I've worked on here before. Instructions here . I don't know if this is an aspect of "Let's make sure people are paying attention and not simply following blindly", or an oversight - The instructions indicate a Meraki Server, when a regular one is the working option here. I have to enable the IoT service on this server. Also, we assign the server an IPv4 address from a DHCP pool instead of giving it a static one. For something that handles our IoT business, perhaps that's safer; Getting a new IPv4 address every week or so is a minimal step against an intruder, but it is a step. There are no devices associated with this new server; In an earlier lab (not shown), I attached them to 'H

Securing Terraform and You Part 1 -- rego, Tfsec, and Terrascan

9/20: The open source version of Terraform is now  OpenTofu     Sometimes, I write articles even when things don't work. It's about showing a learning process.  Using IaC means consistency, and one thing you don't want to do is have 5 open S3 buckets on AWS that anyone on the internet can reach.  That's where tools such as Terrascan and Tfsec come in, where we can make our own policies and rules to be checked against our code before we init.  As this was contract work, I can't show you the exact code used, but I can tell you that this blog post by Cesar Rodriguez of Cloud Security Musings was quite helpful, as well as this one by Chris Ayers . The issue is using Rego; I found a cool VS Code Extension; Terrascan Rego Editor , as well as several courses on Styra Academy; Policy Authoring and Policy Essentials . The big issue was figuring out how to tell Terrascan to follow a certain policy; I made it, put it in a directory, and ran the program while in that directory

Create a Simple Network (Packet Tracer) + A Walkthrough

Again; I've done this, but now there's so many new things, I'm doing it again. The truly new portions were...everything on the right side of this diagram; The cloud needed a coax connector and a copper Ethernet connector. It's all easy to install, turn off the cloud (Weird), install the modules. Getting the Cable section of Connections was an unusual struggle - The other drop down menu had nothing within. It required going into the Ethernet options and setting the Provider Network to 'cable', which is the next step AFTER the drop-downs. The rest was typical DHCP and DNS setups, mainly on the Cisco server down there. The post is rather short - How about adding a video to it? Find out what A Record means - This site says 'Maps a name to an IP address', which is DNS. So it's another name for DNS? You can change them (presumably in a local context) to associate an IP address to another name.