9 Ways You Can Use React Today in 2022

In this post, we will cover 9 Ways You Can Use React in 2022 to build applications. These can range from video stream services to text editors.



1. Websites

The first obvious (but most important) one on the list are web applications. React.js is one of the most popular JavaScript libraries used in the web development community because of its ability to create dynamic and robust user interfaces in a declarative style.

The great thing about React is that it is unopinionated and because of that there is a wide range of possibilities you can do to with it in the way you want to.

In case you didn’t know of some technologies existing for your use case here is a quick list to help you get started using React today:



Static Websites

  • GatsbyJS is the most popular framework for building static websites with a strong focus on SEO. It is fast, flexible, and helps you develop web apps using React. It has been continually staying up to date with the latest technologies over the years as well as applying best practices to search engine algorithms that are constantly changing.

  • NextJS is one of the most popular framework for building hybrid static & server rendered web applications which also uses React.



2. Command Line Interface (CLI) Apps

If you ever wanted to develop your own command line application in JavaScript by using React, you can right now!

ink is a popular JavaScript library for creating component based user interfaces on the command line. To make this possible they use Yoga to build Flexbox layouts in the terminal so most of the CSS properties you would normally use is also available for use right away.

Gatsby, New York Times as well as Twilio have used ink in their projects.

It has a great set of built in components in addition to components built by the community ready to use and if you want to push further you can create your own ink component and share it with the ink community!

Here is an example of ink in use:

#!/usr/bin/env node
import React from 'react'
import meow from 'meow'
import  render  from 'ink'
import App from './App'
import store from './store'

const header = (s: string) => co.fadedBlue(s)
const flag = (s: string) => co.magenta(s)
const cli = meow(
  `
    $header('Usage')

    $header(`Options`)
      $flag(`--config`), $flag(`-c`) Sets the config for operations
`,
  
    flags: 
      config: ,
    ,
  ,
)

render(<App config=cli.config />)



3. Desktop Applications

If you ever thought about creating your own desktop application there are a couple of libraries that might be able to help you out.

Electron is one of the most widely used libraries in the NodeJS community for creating native desktop applications. When you combine react with it it becomes a powerful combination because it makes it fun and easier while still capable of building complex programs!

React NodeGUI is slowly gaining popularity for bringing react directly to the desktop development experience, powered by Qt5.

If you ever decide to go into this path it is worth mentioning some of these libraries that make a great companion to the above:

  1. react-desktop provides a set of ready-to-use react components with the goal of bringing a native desktop experience, featuring many Windows 10 and MacOS Sierra components:

Windows 10:

react-desktop-window-component-for-desktop-applications.png
react-desktop-window-button-component-for-desktop-applications.png
react-desktop-navigation-pane-navpane-react-component.png

MacOS Sierra:

mac-list-react-component
mac-window-component-react-application-macos-sierra.png

  1. react-router-dom can help route your pages using its HashRouter component for file based environments or BrowserRouter for request based environments. This is great because it allows your users to go to their previously visted steps.

  2. Blueprint is another react based component library providing optimized components for building complex data driven interfaces for desktop applications:

blueprint-react-table-component-for-desktop-application.png



4. Videos, Video Players and Streaming

You can combine GatsbyJS, NextJS, or literally any other UI framework to use react and build yourself apps that can play videos or even provide a smooth video streaming experience.

First, here are some libraries that can help with playing videos on your web pages:

  • react-player is a react component for playing videos from variety of URLs including file paths, YouTube, Facebook, DailyMotion, and others. It is a smart component that loads in the appropriate markup and external SDKs to play media from variuos sources.

  • react-video-renderer is also another react component for playing videos

  • react-video-recorder is a react component that allows you to record videos.

  • react-video-progress is a react component that can help show the duration progress of videos at their frame borders:

  • react-video-progress-demo

  • react-modal-video can help you play videos on a modal

  • twilio-video lets you add real time voice and video chat in your applications. This allows multiple people to join the same chat room and have a Zoom-like experience.

You can combine this experience together to create a video on demand (VOD) experiences for your users.

AWS Elemental MediaConvert can help format and compress your videos for delivery to connected devices or televisions by using a high quality video transcoding technology to create on-demand video assets for any device. It does this using a most recent transcoding technology developed by Apple and Microsoft to unify a format that can be used by all users. You would also have to use S3 to create two buckets (one for input and one for output) then use a function to trigger the pipeline for MediaConvert to store the output. These videos are picked up by the CDN you attach to that bucket and can be streamed by your video players. This sounds like a cool project to use react with!



6. Cheat sheets

React serves as great a tool when using it to develop your own cheat sheets due to its component nature. When combined with drag n drop it is almost mother to nature in JavaScript because normally you would have certain notes at certain locations so that you can get the most out of it.

If you wanted to start creating cheat sheets in React, here is a library you can check out:

react-csheets is a react library with the purpose of generating cheat sheets using snippets. It uses a drag n drop api to make smooth transitions between snippets and has over 20 themes to decorate your snippets.

react-csheets-react-library-generate-cheat-sheets-in-javascript



7. Text editors

I’m sure the majority of you reading this have been using the internet for awhile now, so surely you’ve had hands on experience with text editors before. Turns out they aren’t that simple to create though. But you can quickly get started to build your own in react with a couple of libraries readily available:

DraftJS is a library created by the team at Facebook that lets you build rich text editors with… you guessed it: React! It takes some time to get used to but once you start getting it its actually motivating to keep going when you notice progress.

twitter-tweet-clone-draftjs-react-javascript-example.jpg



8. Documentation

Writing documentations should be easy and straight forward. Fortunately there are some tools powered by react that help ease things further in a programmatic way.

You can look into docusaurus if you haven’t already.

Docusaurus is a react library that provides an api to build optimized websites quickly and helps you focus more on your content than structuring your pages. It is developed by the engineers at Facebook (now known as Meta). You can write your content in markdown or mdx and docusaurus will then generate static html files that are ready to serve. Combine it with a blazing fast search component like Algolia and you will attain a very happy audience 🙂

There is also Storybook, a great react library for building user interface components and pages in isolation. The cool part about this approach is that its also naturally great at generating documentations if you have multiple components to document:

storybookjs thumbnail



9. Mobile Apps

In modern day technology mobile apps have become one of the most popular and universal technology for seeking information as well as communication with others, so they are all the rage these days.

It’s not too far different in the JavaScript community as you can still commonly see developers developing in mobile apps with react.

react-native is another library created from the at Facebook that lets you write in react to create native apps for Android and iOS.

Largely known companies like Coinbase, Shopify, Discord and even Walmart all use react native in development.



Conclusion

And that concludes the end of this post! I hope you found this to valuable and look out for more in the future!

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Testing a Mui Date Picker Adaptor Component Integrated with React Hook Form



Subject Under Test

A date picker component integrating mui’s date picker with React Hook Form’s form context. It uses the Controller component from React Hook Form(RHF) and configures mui’s DatePicker to handle validations and more. I use this component instead of mui‘s DatePicker in all my forms.



Behaviours

  1. It inherits all the behaviours from DatePicker of mui and accepts all DatePicker props as-is.
  2. It takes name, formContext and defaultValue required props and registers the DatePicker to the form context of RHF
  3. It has two modes: edit mode and read-only mode. In read-only mode, it is disabled, has no date picker icon button and is rendered as a standard(underline) TextField. In edit mode, it is rendered as outlined TextField.
  4. It builds in the required validation rule and takes a required prop.
  5. It builds in a validation rule for invalid date input
  6. It accepts validation rules and enforces them.
  7. It takes an optional onChange prop. It will update the value and trigger the given onChange method on change.
  8. It has a default mask and date format and can be changed with props.
  9. It defaults to size small, full width and shrink label.
  10. It set time to end of the day.
  11. It takes a style prop for styling the underlying TextField.



Code



Notes

  1. matchMedia is mocked so that the date picker can be rendered in desktop mode with the date picker icon button
  2. TestComponent sets up a React Hook Form environment and shows how the SUT can be used.
  3. FormForTesting is a testing utility component for testing React Hook Form form components.
  4. The tests are grouped into three categories: appearance, behaviours and validations.

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What is Module?

A module is a file containing Python definitions and statements which we can use in other Python programs.
A module is simply a “Python file” which contains code(functions, classes,lists etc) we can reuse in multiple Python programs.

Modules in Python can be of two types:

Built-in Modules.
User-defined Modules.

Modules allows us to use the functionality we need when we need it, and it keeps our code cleaner.

The functions we import as part of a module stays in their own namespace.(A namespace is simply a space within which all names are different from each other). The same name can be reused in different namespaces but two objects can’t have the same name within a single namespace.

For example, Many cities have a street called “Main Street”,
It is okay if ‘different’ cities have that ‘same’ street name but it’s very confusing if two streets in the same city have that same name!

Another example is the folder organization of file systems. One can have a file called “todo” in her work folder as well as her personal folder, but she knows which is which because of the folder it’s in; each folder has its own namespace for files.

One important note, human names are not part of a namespace that applies uniqueness; that’s why governments have invented unique identifiers to assign to people, like passport numbers.

In order to use Python modules, we have to import them into a Python program.

1)If we import morecode in a code, that imports everything in morecode.py. To invoke a function f1 that is defined in morecode.py, we can write morecode.f1().

morecode.f1

Note that we have to explicitly mention morecode again, to specify that we want the f1 function from the morecode namespace.If we just write f1(), python will look for an f1 that was defined in the current file, rather than in morecode.py.

2)We can also give the imported module an alias (a different name, just for when we use it in our program). For example, after executing import morecode as mc,
we would invoke f1 as mc.f1(). We have now given the morecode module the alias mc. Programmers often do this to make code easier to type.

3)A third possibility for importing occurs when we only want to import SOME of the functionality from a module and we want to make those objects be part of the current module’s namespace.
For example, we could write from morecode import f1. Then we could invoke f1 without referencing morecode again: f1().


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Bhagavad Gita API



Introduction

TheAum.org presents a free, anonymous and highly available API for the Bhagavad Gita.



Motivation

Many existing APIs of the Gita requires you to either sign-up or get some token to perform requests.
We feel like this is not something one wants when reading The Gita.
Holy books and texts should be generally available and not holding any string attached to it, therefore we created this completely free and anonymous API to let anyone get the Words of God on the internet, let it be for an Android app or for your next Web Project.



Features

The API has multiple translations and commentaries in two languages: English and Hindi.
There is also available chapters meanings and summaries (Hindi only).



API Routes and Endpoints

By making a GET request to the API homepage (/) you get an answer with all the routes available.

$ curl https://bhagavadgita.theaum.org/

/text/:ch/:verse: "Get text by chapter and verse",
/text/translations/:ch/:verse: "Get text translations by chapter and verse",
/text/transliterations/:ch/:verse: "Get text transliterations by chapter and verse",
/text/commentaries/:ch/:verse: "Get text commentaries by chapter and verse",
/chapters/:ch: "Get chapters",
/chapters/:ch/transliterations: "Get chapters transliterations",
/chapters/:ch/translations: "Get chapters translations",
/chapter/meaning/:ch: "Get chapter meaning",
/chapter/summaries/:ch: "Get chapter summaries"



Examples

Let’s try to get the texts from Chapter 1, verse 1.

$ curl https://bhagavadgita.theaum.org/text/1/1


  "data": [
    
      "id": 1,
      "bg_id": "BG1.1",
      "chapter": "1",
      "verse": "1",
      "shloka": "धृतराष्ट्र उवाच 
  ]


Now, what does that mean? Let’s try to hit the translations endpoint!

$ curl https://bhagavadgita.theaum.org/text/translations/1/1


  "data": [
    
      "id": 1,
      "bg_id": "BG1.1",
      "lang": "hi",
      "name": "Swami Tejomayananda",
      "author": "Swami Tejomayananda",
      "translation": "।।1.1।।धृतराष्ट्र ने कहा -- हे संजय ! धर्मभूमि कुरुक्षेत्र में एकत्र हुए युद्ध के इच्छुक (युयुत्सव:) मेरे और पाण्डु के पुत्रों ने क्या किया?"
    ,
    
      "id": 2,
      "bg_id": "BG1.1",
      "lang": "en",
      "name": "Swami Sivananda",
      "author": "Swami Sivananda",
      "translation": "1.1 Dhritarashtra said  What did my people and the sons of Pandu do when they had assembledntogether eager for battle on the holy plain of Kurukshetra, O Sanjaya."
    ,
    
      "id": 3,
      "bg_id": "BG1.1",
      "lang": "en",
      "name": "Shri Purohit Swami",
      "author": "Shri Purohit Swami",
      "translation": "1.1 The King Dhritarashtra asked: "O Sanjaya! What happened on the sacred battlefield of Kurukshetra, when my people gathered against the Pandavas?""
    ,
    
      "id": 4,
      "bg_id": "BG1.1",
      "lang": "en",
      "name": "Dr.S.Sankaranarayan",
      "author": "Dr.S.Sankaranarayan",
      "translation": "1.1. Dhrtarastra said  O Sanjaya ! What did my men and the sons of Pandu do in the Kuruksetra, the field of  righteousness, where the entire warring class has assembled ?nornO Sanjaya !  What did the selfish intentions and the intentions born of wisdom do in the human body which is the field-of-duties,  the repository of the senseorgans and in which all the murderous ones (passions and asceticism etc.) are confronting [each other]."
    ,
    
      "id": 5,
      "bg_id": "BG1.1",
      "lang": "en",
      "name": "Swami Adidevananda",
      "author": "Swami Adidevananda",
      "translation": "1.1 Dhrtarastra said  On the holy field of Kuruksetra, gathered together eager for battle, what did my people and the Pandavas do, O Sanjaya?"
    ,
    
      "id": 6,
      "bg_id": "BG1.1",
      "lang": "en",
      "name": "Swami Gambirananda",
      "author": "Swami Gambirananda",
      "translation": "1.1. Dhrtarastra said  O Sanjaya, what did my sons (and others) and Pandu's sons (and others) actually do when, eager for battle, they assembled on the sacred field, the Kuruksetra (Field of the Kurus)?"
    ,
    
      "id": 7,
      "bg_id": "BG1.1",
      "lang": "hi",
      "name": "Swami Ramsukhdas",
      "author": "Swami Ramsukhdas",
      "translation": "।।1.1।। धृतराष्ट्र बोले (टिप्पणी प0 1.2) - हे संजय! (टिप्पणी प0 1.3) धर्मभूमि कुरुक्षेत्र में युद्ध की इच्छा से इकट्ठे हुए मेरेे और पाण्डु के पुत्रों ने भी क्या किया?"
    ,
    
      "id": 8,
      "bg_id": "BG1.1",
      "lang": "en",
      "name": "Sri Ramanuja",
      "author": "Sri Ramanuja",
      "translation": "1.1 - 1.19 Dhrtarastra said - Sanjaya said  Duryodhana, after viewing the forces of Pandavas protected by Bhima, and his own forces protected by Bhisma conveyed his views thus to Drona, his teacher, about the adeacy of Bhima's forces for conering the Kaurava forces and the inadeacy of his own forces for victory against the Pandava forces. He was grief-stricken within.nnObserving his (Duryodhana's) despondecny, Bhisma, in order to cheer him, roared like a lion, and then blowing his conch, made his side sound their conchs and kettle-drums, which made an uproar as a sign of victory. Then, having heard that great tumult, Arjuna and Sri Krsna the Lord of all lords, who was acting as the charioteer of Arjuna, sitting in their great chariot which was powerful enough to coner the three worlds; blew their divine conchs Srimad Pancajanya and Devadatta. Then, both Yudhisthira and Bhima blew their respective conchs separately. That tumult rent asunder the hearts of your sons, led by Duryodhana. The sons of Dhrtarastra then thought, 'Our cause is almost lost now itself.' So said Sanjaya to Dhrtarastra who was longing for their victory.nnSanjaya said to Dhrtarastra:  Then, seeing the Kauravas, who were ready for battle, Arjuna, who had Hanuman, noted for his exploit of burning Lanka, as the emblem on his flag on his chariot, directed his charioteer Sri Krsna, the Supreme Lord-who is overcome by parental love for those who take shelter in Him who is the treasure-house of knowledge, power, lordship, energy, potency and splendour, whose sportive delight brings about the origin, sustentation and dissolution of the entire cosmos at His will, who is the Lord of the senses, who controls in all ways the senses inner and outer of all, superior and inferior - by saying, 'Station my chariot in an appropriate place in order that I may see exactly my enemies who are eager for battle.'"
    ,
    
      "id": 9,
      "bg_id": "BG1.1",
      "lang": "en",
      "name": "Sri Abhinav Gupta",
      "author": "Sri Abhinav Gupta",
      "translation": "1.1  Dharmaksetre etc. Here some [authors] offer a different explanation as1 :-Kuruksetra : the man's body is the ksetra i.e., the facilitator, of the kurus, i.e., the sense-organs. 2 The same is the field of all wordly duties, since it is the cuse of their birth; which is also the field of the righteous act that has been described as :nn'This is the highest righteous act viz., to realise the Self by means of the Yogas';nnnand which is the protector4 [of the embodied Self] by achieving emancipation [by means of this], through the destruction of all duties. It is the location where there is the confrontation among all ksatras, the murderous ones-because the root ksad means 'to kill' - viz, passion and asceticism, wrath and forbearance, and others that stand in the mutual relationship of the slayer and the slain. Those that exist in it are the mamakas,-i.e., the intentions that are worthy of man of ignorance and are the products of ignorance-and those that are born of Pandu: i.e., the intentions, of which the soul is the very knowledge itself5 and which are worthy of persons of pure knowledge. What did they do? In other words, which were vanished by what? Mamaka : a man of ignorance as he utters [always] 'mine'6. Pandu : the pure one.7"
    ,
    
      "id": 10,
      "bg_id": "BG1.1",
      "lang": "en",
      "name": "Sri Shankaracharya",
      "author": "Sri Shankaracharya",
      "translation": "1.1 Sri Sankaracharya did not comment on this sloka. The commentary starts from 2.10."
    ,
    
      "id": 11,
      "bg_id": "BG1.1",
      "lang": "hi",
      "name": "Sri Shankaracharya",
      "author": "Sri Shankaracharya",
      "translation": "।।1.1।।Sri Sankaracharya did not comment on this sloka."
    
  ]




Technical information

The REST API has a very strong caching policy to allow latest latency possible all over the world.

2022-01-21T16:00:15.772 app[348d4703] cdg [info] [GIN] 2022/01/21 - 16:00:15 | 200 | 150.994µs | REMOTE_IP | GET "/text/translations/1/1"

As you can see 150.994µs is the time needed to query the cache database for the translation.



Tech Stack

The API is written in Golang by using the GIN framework and Gorm.
The Database is SQLite.
The project runs on Cloudflare and Fly.io



Support

TheAum.org and The Bhagavad Gita API doesn’t earn a single penny from Ads, you will never find them on our pages and domains.
However running these websites isn’t free.
Running servers costs in terms of Bandwidth and CPU usage to handle the traffic.
If you can please donate to help the project keep going.

If you wish to support us you can click the following button:

Buy Me A Coffee


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A Swiss Army Knife for JS Variables: Var or Let or Const?



Introduction

Yet another blog explaining Var, Let and Const but I promise this is the only one you need.

ECMASCRIPT2015, also known as ES6 introduced a lot of awesome features. One of the features was the addition of let and const for declaring variables. Previously developers used var for variable declaration, so what was the need of bringing new ones?

If you don’t know what let and const brings to the table and how are they different from each other, this blog post is for you. I will compare them based on usage, scope, and hoisting.



Var

Before the introduction of ES6, the only way to define variables in JavaScript was to use the var keyword. For many years, it worked fine, however var differs from other programming languages in terms of variable scoping leading to unwanted bugs that are hard to track.

The below code example demonstrates the declaration of a variable with the var keyword:

var declaredWithVar = "welcome to the blog";
console.log(declaredWithVar);  //welcome to the blog



Scope

The Scope refers to the present context of code, which decides the accessibility of the variables.
The scope is of two types Global and Local:

  • Variables that are declared outside of a block are known as Global variables.
  • Variables that are declared inside of a block are known as Local variables.

The variables declared with var are globally scoped when declared outside a function. Any variable declared with var outside of a function block is accessible across the whole window.

var is a function scoped when it is declared within a function which means that it is accessible within that function only.

Look at the example below to understand further:

var globalScopedVar = "declared globally"

function varScopeCheck()
  var scopingOfVarInFunc = "declared inside function"
  console.log(scopingOfVarInFunc)


console.log(scopingOfVarInFunc) //Uncaught ReferenceError: scopingOfVarInFunc is not defined
console.log(varScopeCheck()) //declared inside function
console.log(globalScopedVar) //declared globally

As you can see, we cannot access scopingOfVarInFunc outside of the function as the variable is locally scoped but we can access the globalScopedVar as it is globally scoped.

var can also be redeclared and updated.

This means the value of the variable can be updated by reinitializing and the variable declared with the var keyword can be declared again and again with the same or different values.

Look at the example below to understand further:

var declaredVar = "First time"
var updatedVar = "Old value"

var declaredVar = "Second time"
updatedVar = "New value"

console.log(declaredVar) // Second Time
console.log(updatedVar) // New value



Hoisting

Hoisting is the process by which the interpreter allocates memory for variable and function declarations prior to executing the code. This allows us to use a variable before it has been declared and initialized.

For example:

 console.log(hoistedVar); //undefined
 var hoistedVar = "I'll be hoisted"

why undefined? why not defined error?
var variables are hoisted to the top of the scope and initialized with the value undefined.



Problem with var

var nameUsingVar = "Michael"
if(true)
  var nameUsingVar = 'Mike instead'

console.log(nameUsingVar) // Mike instead

In the above code example, global scoped nameUsingVar is replaced by the block-scoped nameUsingVar and we get the unexcepted value. Well, it is not a problem if it’s intentional but imagine managing your variables after 1000s of lines of code. This will become tricky to work with and cause a lot of bugs in your code.

That is why let and const were introduced and widely used.



Let

let came as an improvement over var by being block-scoped which solves the problem discussed above.

The below code example demonstrates the declaration of a variable with the let keyword:

let declaredWithLet = "I am preferred over var";
console.log(declaredWithLet);  //I am preferred over var



Scope

Variables declared with let are block-scoped which means that a variable declared in a block with let is only available for use within that block. Variables declared outside blocks are global scoped.

Let’s understand it with an example:

let globalScopedLet = "declared globally"

function letScopeCheck()
  let scopingOfLetInFunc = "declared inside function"
  console.log(scopingOfLetInFunc)


console.log(scopingOfLetInFunc) //Uncaught ReferenceError: scopingOfLetInFunc is not defined
console.log(letScopeCheck()) //declared inside function
console.log(globalScopedLet) //declared globally

It solves the problem with var:

let nameUsingLet = 'Michael'
if(true)
    let nameUsingLet = 'Mike'

console.log(nameUsingLet) //Michael

As you can see, we get the expected output as it is block scoped.

let cannot be re-declared but can be updated within a scope block.

let nameUsingLet = 'Michael'

let nameUsingLet = 'Mike'
//SyntaxError: Identifier 'greeting' has already been declared

if(true)
  /* This is a different scope, so redeclaration here is ok.*/
    let nameUsingLet = 'Michel'
    console.log(nameUsingLet) //Michel


console.log(nameUsingLet) //Michael



Hoisting

let declarations are hoisted but it’s different from var.

console.log(variableUsingLet); // ReferenceError: Cannot access 'a' before initialization
console.log(variableUsingVar); // prints undefined as expected
let variableUsingLet = 10;
console.log(variableUsingLet); // 10
var variableUsingVar = 15;
console.log(window.variableUsingLet); // undefined
console.log(window.variableUsingVar); // 15

It looks like let isn’t hoisted, but it is, let’s understand:
Both variableUsingLet and variableUsingVar are actually initialized as undefined in hoisting stage. But variableUsingVar is inside the storage space of GLOBAL, and variableUsingLet is in a separate memory object called script, where it can be accessed only after assigning some value to it first ie. one can access variableUsingLet only if it is assigned. Thus, it throws a ReferenceError.

Temporal Dead Zone: Time elapsed since the let variable was hoisted until it was initialized with a value.

So any line till before “let variableUsingLet = 10” is the Temporal Dead Zone for variableUsingLet.
Since variableUsingLet is not accessible on global, it’s not accessible in window/this also.
ReferenceError is thrown when variables are in the Temporal Dead Zone, SyntaxError doesn’t even let us run a single line of code.

Finally, let’s learn about const.



Const

Just like the name, const variables are constant, they cannot be redeclared or updated and if we try to do so, we will get an error.

With only var, the way to signify a constant variable was to write the variable name in all caps but it still could be updated and redeclared. const solves this problem along with var scoping problem.

const variableUsingConst = 10;
variableUsingConst = 20;
console.log(variableUsingConst)
//TypeError: Assignment to constant variable.



Scope

It is also block-scoped and works similarly to let.

const nameUsingConst = 'Michael'
if(true)
    const nameUsingConst = 'Mike'

console.log(nameUsingConst) //Michael



Hoisting

It is similarly hoisted as let.

console.log(variableUsingConst); // ReferenceError: Cannot access 'variableUsingConst' before initialization
const variableUsingConst = 10;
console.log(variableUsingConst); // 10



Conclusion

Keyword Scope Updateable Redeclareable Hoisted
var Function scope Yes Yes Yes
let Block scope Yes No No
const Block scope No No No
  • Try using const wherever possible.
  • If not use let, Avoid var.
  • Declare and initialize all variables with let to the top to avoid errors and shrink the Temporal Dead Zone window to zero.

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Top 17 web scraping tools for data extraction in 2022

Web scraping tools are software specially developed to extract useful information from websites. These tools are useful for anyone looking to collect any form of data from the Internet.
Here is a curated list of the best web scraping tools This list includes commercial and open source tools with popular features and the latest download link.



1. Bright Data

Bright Data is number one. 1 in the world, which provides a cost-effective way to perform large-scale, fast, and stable public web data collection, effortlessly convert unstructured data into structured data and deliver a superior customer experience, all while being completely transparent and compliant.

Bright Data’s Nextgen Data Collector provides automated, personalized data flow in a single dashboard, regardless of collection size. From eCom trends and social media data to competitive intelligence and market research, datasets are tailored to business needs. Focus on your core business by accessing reliable industry data on autopilot.

Features:

  • Most efficient
  • Most reliable
  • Most flexible
  • Fully Compliant
  • 24/7 Customer Support



2) Scrapingbee

Scrapingbee is a web scraping API that handles headless browsers and proxy management. It can run Javascript on pages and rotate proxies for every request so you get the raw HTML page without being blocked. They also have a dedicated API for Google search scraping

Features:

  • Supports JavaScript rendering
  • It provides automatic proxy rotation.
  • You can directly use this application on Google Sheet.
  • The application can be used with a chrome web browser.
  • Great for scraping Amazon
  • Support Google search scraping



3) Scraping-Bot

ScrapingBot.io is an effective tool for extracting data from a URL. Provides APIs tailored to your scraping needs: a generic API for fetching raw HTML from a page, a specialized API for scraping retail websites, and an API for scraping property listings from websites real estate.

Features:

  • JS rendering (Headless Chrome)
  • High-quality proxies
  • Full Page HTML
  • Up to 20 concurrent requests
  • Geotargeting
  • Allows for large bulk scraping needs
  • Free basic usage monthly plan



4) Newsdata.io

Newsdata.io is a great tool if you want to extract news data from the web, as it is a news API, it crawls and stores huge amounts of news data in their database that you can access through Newsdata.io’s news API. It provides access to structured news data in JSON format and allows access to its historical news database.

Features:

  • Get the latest news data with their news API
  • The best alternative for Google news API.
  • Advanced filters to get the most relevant data.
  • Has massive news database to access.



5) Scraper API

Scraper API tool helps you manage proxy, browser, and CAPTCHA. This allows you to get HTML from any web page with a simple API call. It’s easy to integrate as you just need to send a GET request to the API endpoint with your API key and URL.

Features:

  • Helps you to render JavaScript
  • It allows you to customize the headers of each request as well as the request type
  • The tool offers unparalleled speed and reliability which allows building scalable web scrapers
  • Geolocated Rotating Proxies



6) Scrapestack

Scrapestack is a REST API for real-time web scraping. More than 2,000 companies use scrapestack and trust this dedicated API supported by apilayer. The scrapestack API allows businesses to scrape web pages in milliseconds, managing millions of proxy IPs, browsers, and CAPTCHAs.

Features:

  • Uses a pool of 35+ million data centers and global IP addresses.
  • Access to 100+ global locations to originate web scraping requests.
  • Allows for simultaneous API requests.
  • Supports CAPTCHA solving and JavaScript rendering.
  • Free & premium options.



7) Agenty

Agenty is a robotic process automation software for data scraping, text mining, and OCR.

Creates an agent with just a few mouse clicks. This app helps you reuse all your processed data for your analytics.

Features:

  • It enables you to integrate with Dropbox and secure FTP.
  • Provides you with automatic email updates when your job is completed.
  • You can view all activity logs for all events.
  • Helps you to boost your business performance.
  • Enables you to add business rules and custom logic with ease.



8) Import.io

This web scraping tool helps you train your datasets by importing data from a specific webpage and exporting the data in CSV format. It is one of the best data scraper tools that allows you to integrate data into applications using APIs and webhooks.

Features

  • Easy interaction with webforms/logins
  • Schedule data extraction
  • You can store and access data by using Import.io cloud
  • Gain insights with reports, charts, and visualizations
  • Automate web interaction and workflows



9) Dexi Intelligent

Dexi intelligent is a web scraping tool that allows you to convert an unlimited amount of web data into immediate business value. This web scraping tool allows you to save money and time for your company.

Features:

  • Increased efficiency, accuracy, and quality
  • Ultimate scale and speed for data intelligence
  • Fast, efficient data extraction
  • High scale knowledge capture



10) Outwit

It’s a Firefox extension that you can get from the Firefox add-ons store. To purchase this product, you will have three distinct options based on your needs. 1. Professional edition, 2. Expert edition, and 3. Enterprise edition

Features:

  • This data scraper tool allows you to grab contacts from the web and email source simply
  • No programming skill is needed to exact data from sites using Outwit hub
  • With just a single click on the exploration button, you can launch the scraping on hundreds of web pages



11) PareseHub

ParseHub is a free web scraping application. This advanced web scraper makes data extraction as simple as clicking the data you require. It is one of the best data scraping tools, allowing you to save your scraped data in any format for further analysis.

Features:

  • Clean text & HTML before downloading data
  • The easy to use graphical interface
  • This website scraping tool helps you to collect and store data on servers automatically



12) Diffbot

Diffbot enables you to easily obtain various types of useful data from the web. You don’t have to pay for expensive web scraping or manual research. With AI extractors, the tool will allow you to extract structured data from any URL.

Features:

  • Offers multiple sources of data form a complete, accurate picture of every entity
  • Provide support to extract structured data from any URL with AI Extractors
  • Helps you to scale up your extraction to 10,000s domains with
  • Crawlbot
  • Knowledge Graph feature offers accurate, complete, and deep data from the web that BI needs to produce meaningful insights.



13) Data streamer

The Data Stermer tool allows you to retrieve social media content from all over the internet. It is one of the best web scrapers for extracting critical metadata via natural language processing.

Features:

  • Integrated full-text search powered by Kibana and Elasticsearch
  • Integrated boilerplate removal and content extraction based on information retrieval techniques
  • Built on a fault-tolerant infrastructure and ensure high availability of information
  • Easy to use and comprehensive admin console



14) FMiner

FMiner is another popular web scraping, data extraction, crawling screen scraping, macro, and web support tool for Windows and Mac OS.

Features:

  • Allows you to design a data extraction project by using an easy to use the visual editor
  • Helps you to drill l through site pages using a combination of link structures, drop-down selections, or url pattern matching
  • You can extract data from hard to crawl Web 2.0 dynamic websites
  • Allows you to target website CAPTCHA protection with the help of third-party automated decaptcha services or manual entry



15) Sequentum

The Sequentum is a robust big data solution for dependable web data extraction. It is one of the best web scrapers for scaling your organization. It includes user-friendly features such as a visual point-and-click editor.

Features:

  • Extract web data faster and faster way compares to other solution
  • Help you to build web apps with the dedicated web API that allow you to execute web data directly from your website
  • Helps you move between various platforms



16) Mozenda

Mozenda extracts text, images, and PDF content from web pages. It is one of the best web scraping tools for organizing and preparing data files for publication.

Features:

  • You can collect and publish your web data to your preferred Bl tool or database
  • Offers point-and-click interface to create web scraping agents in minutes
  • Job Sequencer and Request Blocking features to harvest web data in a real-time
  • Best in class account management and customer support



17) Data Miner Chrome Extension

This Data Miner chrome extension aids in web scraping and data acquisition. It allows you to scrape multiple pages and provides dynamic data extraction.

Features:

  • Scraped data is stored in local storage
  • Multiple data selection types
  • Web Scraper Chrome extension extracts data from dynamic pages
  • Browse scraped data
  • Export scraped data as CSV
  • Import, Export sitemaps

Original Post: https://www.guru99.com/web-scraping-tools.html


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Best Way to Get Last Item in an Array



Hello Folks 👋

What’s up, this is SnowBit here. I am a young passionate and self-taught developer and have an intention to become a successful developer.

Today, I am here with a basic topic mostly for beginners and revisers.



Avoid this

const arr = ["JS", "PY", "CSS"]
const lastItem = arr[2]

Don’t do this for getting the last item of an array. Let me explain, this is a small array and contains only 3 items that are easily countable but, what if there are hundred’s of items in an array then this method will make you mad 🤯



Do this

const arr = ["JS", "PY", "CSS"]
const lastItem = arr[arr.length - 1]

Here, arr.length becomes dynamic, it increases as you increase items in arr no matter how many you add and that will not make you mad 😜

Thank you for reading, have a nice day!
Your appreciation is my motivation 😊




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