Karthik Dev Articles

How I Created an Interview CLI with Node.js for self-interview preparation

Karthik — Sat, 02 Oct 2021 18:48:05 GMT

Hi Guys, In this article, we will focus on topics of Node.js, CLI, and Interview Preparation.

I have created a self-interview preparation CLI toolkit, which will show me random questions whenever I run a CLI command called "interview".

Sounds cool right.

Purpose

I felt I would require a real-time experience of attending an interview, but I wanted to have control over what I could be expecting, and still having the random unexpectedness of attending an interview.

This simple project I felt was in the right direction.

Prerequisites/Tools required.

Latest version of Node.js installed(I used v14.18.0)
Text editor - Visual Studio Code

Next, open your project folder and enter the below commands to create and initiate the node.js project setup.

mkdir interview-cli
cd interview-cli
npm init -y

Next, open the interview-cli folder and create a bin folder and an index.js file within it.

//bin/index.js
#!/usr/bin/env node

console.log("Welcome to the Mock Interview!!");

A string that begins with #! is called a “shebang”. With this string, we are explicitly stating the command line/terminal to run our script with node.

Now open the package.json file and update the main key value to the path "bin/index.js" and append a new key bin with the below code.

"bin": {
    "interview": "./bin/index.js"
 }

Make sure you add a comma(",") to the end of the previous line for the above step.

Your package.json must look like this.

{
  "name": "interview-cli",
  "version": "1.0.0",
  "description": "",
  "main": "bin/index.js",
  "scripts": {},
  "author": "",
  "license": "ISC",
  "bin": {
    "interview": "./bin/index.js"
  }
}

At this point, we can run the application like any other node application with the below command.

node .

But since our goal is to run the application from anywhere, I want to simply open my computer/laptop and hit the command line to prepare for the interview. For achieving that, we install our application globally with the below command.

npm install -g .

This installs our script globally. This means the "interview" command mentioned in the bin key section in the package.json file is made available to the command line.

Let's run our script globally with the below command

interview

Output:

Let's now create few questions for the interview in a file called mock-interview-questions.txt at the root of the project

Now let's add the script to show a random interview question when we enter "interview" in the command line.

//bin/index.js
#!/usr/bin/env node

const fs = require("fs");
const crypto = require("crypto");

try {
  let data = fs.readFileSync("mock-interview-questions.txt", "utf8");
  let questions = data.split("\r\n");

  const n = crypto.randomInt(0, questions.length);

  for (let i = 0; i < 10; i++) console.log();
  console.log(questions[n]);
  for (let i = 0; i < 10; i++) console.log();
} catch (err) {
  console.error(err);
}

For the tutorial I have kept the number of questions to 10, but in reality, I would suggest you add at least 50 questions for keeping the interview interesting and helpful for you

Final Output

Creating a Kanban Board with HTML, CSS & JavaScript

Karthik — Sun, 13 Jun 2021 07:56:29 GMT

In this article, we are building a Kanban Board with plain HTML, CSS & JavaScript. This article aims to show, how modern UX designs and functionality can also be achieved with much simpler elements of HTML, CSS & JavaScript. This is where it all started right!

What is Kanban Board? Why use it?

Kanban is a project management tool, used by many software development teams, working with agile processes.

It was designed to help visualize work, reduce work in progress tasks, and maximize the efficiency of teams.

Kanban uses visual cards, columns, and continuous improvement ideology to help teams achieve goals.

"Kanban" is the Japanese word for "visual signal." If you work in services or technology, your work is oftentimes invisible and intangible. A kanban board helps make your work visible so you can show it to others and keep everyone on the same page.

Let's Start

Kanban Board, which we are going to build, should eventually look like this

And we must be able to move tasks like this

Initial Folder Structure

HTML

HTML (HyperText Markup Language) is the most basic building block of the Web. It defines the meaning and structure of web content.

Iteration 1

Initial HTML Boilerplate & Skeleton for kanban.html

<!DOCTYPE html>
<html lang="en">
<head>
    <title>Kanban Board</title>
</head>
<body>
    <div class="container">
        <div class="kanban-heading">
            <strong class="kanban-heading-text">Kanban Board</strong>
        </div>
        <div class="kanban-board">
            <div id="todo">To Do</div>
            <div id="inprogress">In Progress</div>
            <div id="done">Done</div>
        </div>
    </div>
</body>
</html>

Output

Iteration 2

Adding properties to HTML for working better with CSS later. This means CSS can identify HTML better with these properties.

kanban.html

<body>
    <div class="container">
        <div class="kanban-heading">
            <strong class="kanban-heading-text">Kanban Board</strong>
        </div>
        <div class="kanban-board">
            <div class="kanban-block" id="todo">
                <strong>To Do</strong>
            </div>
            <div class="kanban-block" id="inprogress">
                <strong>In Progress</strong>
            </div>
            <div class="kanban-block" id="done">
                <strong>Done</strong>
            </div>
        </div>
    </div>
</body>

Output

CSS

Cascading Style Sheets is used to format & style, the layout of a page

Iteration 3

Link CSS to kanban.html

<head>
    <link rel="stylesheet" href="./kanban.css">
    <title>Kanban Board</title>
</head>

Iteration 4

Adding CSS to kanban.css

Container & Head

.container {
  width: 70%;
  min-width: 50%;
  margin: auto;
  display: flex;
  flex-direction: column;
}

.kanban-heading {
  display: flex;
  flex-direction: row;
  justify-content: center;
  font-family: sans-serif;
}

.kanban-heading-text {
  font-size: 1.8rem;
  background-color: tomato;
  padding: 0.8rem 1.7rem;
  border-radius: 0.5rem;
  margin: 1rem;
}

Output

Board sections

.kanban-board {
  display: flex;
  flex-direction: row;
  justify-content: space-between;
  font-family: sans-serif;
}

.kanban-block {
  padding: 0.6rem;
  width: 30.5%;
  min-width: 14rem;
  min-height: 4.5rem;
  border-radius: 0.3rem;
}

#todo {
  background-color: #fec6d1;
}

#inprogress {
  background-color: #ffaf00;
}

#done {
  background-color: #018b01;
}

Output

Body

body {
  background-color: black;
}

Output

As we see now, the output is much better after adding the magic of CSS to it.

Let's now complete the remaining part of adding sample tasks and it's styling to the Kanban Board

HTML

Iteration 5

Adding sample tasks to "To Do" section kanban.html

<div class="kanban-block" id="todo">
    <strong>To Do</strong>
    <div class="task-button-block">
        <button id="task-button">Create new task</span>
    </div>
    <div class="task" id="task1">
        <span>Task 1</span>
    </div>
    <div class="task" id="task2">
        <span>Task 2</span>
    </div>
    <div class="task" id="task3">
        <span>Task 3</span>
    </div>
    <div class="task" id="task4">
        <span>Task 4</span>
    </div>
    <div class="task" id="task5">
        <span>Task 5</span>
    </div>
    <div class="task" id="task6">
        <span>Task 6</span>
    </div>
</div>

Iteration 6

Adding styles for sample tasks to kanban.css

.task {
  background-color: white;
  margin: 0.2rem 0rem 0.3rem 0rem;
  border: 0.1rem solid black;
  border-radius: 0.2rem;
  padding: 0.5rem 0.2rem 0.5rem 2rem;
}

#task-button {
  margin: 0.2rem 0rem 0.1rem 0rem;
  background-color: white;
  border-radius: 0.2rem;
  width: 100%;
  border: 0.25rem solid black;
  padding: 0.5rem 2.7rem;
  border-radius: 0.3rem;
  font-size: 1rem;
}

Output

As we can see, with a structured HTML & CSS it only gets better

Javascript

JavaScript is a scripting or programming language that allows you to implement complex features on web pages

Time for some actions.

In our Kanban Board, I want to drag and drop my tasks from "To Do" to "In Progress" and "In Progress" to "Done" Status.

For this, I am going to use the HTML Drag & Drop API,

HTML Drag and Drop interfaces enable applications to use drag-and-drop features in browsers. The user may select draggable elements with a mouse, drag those elements to a droppable element, and drop them by releasing the mouse button.

Let me show you all code & deduce it step by step.

<!DOCTYPE html>
<html lang="en">
<head>
    <link rel="stylesheet" href="./kanban.css">
    <title>Kanban Board</title>
    <script>
        function drag(ev) {
            ev.dataTransfer.setData("text", ev.target.id);
        }

        function allowDrop(ev) {
            ev.preventDefault();
        }

        function drop(ev) {
            ev.preventDefault();
            var data = ev.dataTransfer.getData("text");
            ev.target.appendChild(document.getElementById(data));
        }
    </script>
</head>
<body>
    <div class="container">
        <div class="kanban-heading">
            <strong class="kanban-heading-text">Kanban Board</strong>
        </div>
        <div class="kanban-board">
            <div class="kanban-block" id="todo" ondrop="drop(event)" ondragover="allowDrop(event)">
                <strong>To Do</strong>
                <div class="task-button-block">
                    <button id="task-button">Create new task</span>
                </div>
                <div class="task" id="task1" draggable="true" ondragstart="drag(event)">
                    <span>Task 1</span>
                </div>
                <div class="task" id="task2" draggable="true" ondragstart="drag(event)">
                    <span>Task 2</span>
                </div>
                <div class="task" id="task3" draggable="true" ondragstart="drag(event)">
                    <span>Task 3</span>
                </div>
                <div class="task" id="task4" draggable="true" ondragstart="drag(event)">
                    <span>Task 4</span>
                </div>
                <div class="task" id="task5" draggable="true" ondragstart="drag(event)">
                    <span>Task 5</span>
                </div>
                <div class="task" id="task6" draggable="true" ondragstart="drag(event)">
                    <span>Task 6</span>
                </div>
            </div>
            <div class="kanban-block" id="inprogress" ondrop="drop(event)" ondragover="allowDrop(event)">
                <strong>In Progress</strong>
            </div>
            <div class="kanban-block" id="done" ondrop="drop(event)" ondragover="allowDrop(event)">
                <strong>Done</strong>
            </div>
        </div>
    </div>
</body>
</html>

Using draggable="true" property, we are identifying, what is a draggable element
Using ondragstart="drag(event)", we are mentioning what method to use when the element is dragged.
With the following function call, we are defining what data needs to be dragged, in our case, it's the HTML element.
```
function drag(ev) {
     ev.dataTransfer.setData("text", ev.target.id);
}
```
ondrop="drop(event)" specifies when data is dropped, a drop event occurs and we call the drop method

This function sets data to the target element

function drop(ev) {
     ev.preventDefault();
     var data = ev.dataTransfer.getData("text");
     ev.target.appendChild(document.getElementById(data));
}

Output

Additional Features added

Creating a new Task

Features Todo

Adding State to store information
Editing existing task information
Create tasks to other states(In Progress, Done)
Many more...

Track further changes of code here - Kanban Board

Well, is this solution perfect?

No, it isn't

I am getting some side effects like this Haha!

But definitely, worth learning as a starter.

Let me know, how this issue can be resolved.

Thanks for reading through this starter. This completes my first article.