DEV Community: Vishal Yadav

SECURITY GROUP IN AWS VPC

Vishal Yadav — Sat, 07 Dec 2024 17:28:12 +0000

Secrity Groups

Security groups allow specific inbound and outbound traffic at resources level (ex: EC2 instance). when you launch a instance then you can associate it with one or more security groups. Each instance in your VPC could belong to different set of security groups. If you don’t specify a security , when you launching a instance then the instance is automatically associate with default security groups for it’s VPC.
You can assign a security group only to resources which created in same VPC as the security group. You can assign multiple security groups to a resource.
Security groups are stateful. For example, if you send a request from instance, the response traffic for that request is allowed to reach the instance regardless of the inbound security groups rules.

Security group example

The following diagram shows a VPC with two security groups and two subnets. The instances in subnet A have the same connectivity requirements, so they are associated with security group 1. The instances in subnet B have the same connectivity requirements, so they are associated with security group 2. The security group rules allow traffic as follows:
The first inbound rule in security group 1 allows SSH traffic to the instances in subnet A from the specified address range (for example, a range in your own network).
The second inbound rule in security group 1 allows the instances in subnet A to communicate with each other using any protocol and port.
The first inbound rule in security group 2 allows the instances in subnet B to communicate with each other using any protocol and port.
The second inbound rule in security group 2 allows the instances in subnet A to communicate with the instances in subnet B using SSH.
Both security groups use the default outbound rule, which allows all traffic.

Creating The object in the JavaScript

Vishal Yadav — Sat, 08 Jul 2023 05:42:37 +0000

## First Method

First of all we create a object of const type then I assign a value to that object and name of that object is object1.
Using the dot operator we access the all element of object1.

const object1={a:'Ajeet Rai',b:'Rajat Yadav',c:'Veeresh Maurya'};
console.log(object1.a);  //Ajeet Rai   
console.log(object1.b);   //Rajat Yadav
console.log(object1.c);   //Veeresh Maurya

## Second Method

In second method we assign a value to all variable separately and the create a object and assign them.

const a='Uttam';
const b='Sudeep';
const c='Shruti';
const object2={a:a,b:b,c:c};
console.log(object2.a);   //Uttam
console.log(object2.b);  //Sudeep
console.log(object2.c); // Shruti

## Third Method

In this method only different in the assigning the value of the variable in the object3. see in the below example.

const object3={a,b,c};
console.log(object3.a);  //Uttam
console.log(object3.b);  //Sudeep
console.log(object3.c);  //Shruti

Hello World!

RSA ALGO in java

Vishal Yadav — Fri, 16 Dec 2022 10:49:26 +0000

import java.io.*;
import java.math.*;
import java.util.*;

public class Main {

    public static double gcd(double a, double h)
{
    /*
        * This function returns the gcd or greatest common
        * divisor
        */
    double temp;
    while (true) {
    temp = a % h;
    if (temp == 0)
        return h;
    a = h;
    h = temp;
    }
}
    public static void main(String args[]) {
       double p = 3;
    double q = 7;

    // Stores the first part of public key:
    double n = p * q;

    // Finding the other part of public key.
    // double e stands for encrypt
    double e = 2;
    double phi = (p - 1) * (q - 1);
    while (e < phi) {
    /*
            * e must be co-prime to phi and
            * smaller than phi.
            */
    if (gcd(e, phi) == 1)
        break;
    else
        e++;
    }
    int k = 2; // A constant value
    double d = (1 + (k * phi)) / e;

    // Message to be encrypted
    double msg = 12;

    System.out.println("Message data = " + msg);

    // Encryption c = (msg ^ e) % n
    double c = Math.pow(msg, e);
    c = c % n;
    System.out.println("Encrypted data = " + c);

    // Decryption m = (c ^ d) % n
    double m = Math.pow(c, d);
    m = m % n;
    System.out.println("Original Message Sent = " + m);
    }
}

How to delete the branch and create the new branch

Vishal Yadav — Sun, 21 Aug 2022 10:45:00 +0000

For example:
This given command for go to main branch or I can also say that this command is use for changing the branch.

git checkout <branch name in which you go back>

Delete a branch with

git branch -d <branch name>

for creating the new branch in the main or master branch I can use the given command.

git branch -b <branch name>

Done☺
.

IF you want to know more how to contribute on the opensource code on github

Some Important Command of git command as below

Vishal Yadav — Fri, 19 Aug 2022 08:31:14 +0000

`git init for initialization
git status
git commit -m "first commit"
git add . or git add file name
git push -u origin master

for changing the name
git config --global user.name "name"
git config --global user.email "email@gmail.com"

for checking the email or name
git config user.email
git config user.name`

How to solve id_ed25519 file

Vishal Yadav — Fri, 19 Aug 2022 08:12:00 +0000

When I created the SSH key for the git then I face the error
when i running the command

ssh-add ~/.ssh/id_ed25519

of id_ed25519 no such file found.

Solution

1.

change the file name id_rsa.
ssh-add ~/.ssh/id_rsa

2.

For copy the key we follow the given command
clip < ~/.ssh/id_rsa.pub

3.

At last one more command.
Just add Github fingerprint to known hosts this way:

ssh-keyscan -t rsa github.com >> ~/.ssh/known_hosts

then push the project
HAPPY CODING☺☺☺

Top 9 ways to become a successful self-taught developer.

Vishal Yadav — Fri, 19 Aug 2022 04:53:26 +0000

Introduction

The term "self-taught" developer is frequently used to refer to people who have studied coding/programming on their own by reading books, taking online classes and doing other kinds of independent study. Since you are not being forced/required to take lessons by a teacher or educational system, this can be an excellent approach to learn how to program because it gives people the freedom—and flexibility—to concentrate on learning methods that suit them best. Self-taught developers can build their skills by using a variety of methods other than simply reading books or watching internet/youtube videos. We'll explore nine different techniques—hacks, tips and tricks inspired by real life experiences—in this article!

1. Start each day with a plan

The first hack is to start each day with a plan. This can be as simple as writing down your goals and objectives for the day, or it can be more complex, such as creating a detailed lists/spreadsheet with all of your tasks and timelines.

Start with Plan

Once you’ve jot that down, you need to make sure that everything else in your journey supports these goals:

Plan out your week ahead of time — even if it means waking up at 5 AM on Saturday morning to do so!
Create a calendar reminder system so that nothing gets lost in time(e.g., "I will start working on XYZ programming language/project by Monday afternoon")
This hack/technique is all about building momentum. If you don’t start early enough, it can become easy to get caught up in other activities that aren’t related to your goals for the day. It also helps make sure that everything gets done on time and that nothing falls through the cracks.

2. Take short breaks often

When you're programming/coding, it's easy to get into the zone and stay there for hours on end without realizing how much time has passed. Break periods should be used as a way to keep your brain fresh, functioning and aware of what's happening around you, so that when you return back to coding, there will be no surprises or obstacles in your way.

Short Break

How frequently should breaks be taken? It is impossible to predict. A fair general rule of thumb would be 20 to 30 minutes for every two hours spent coding, although everyone has a different working style. Make sure to take a break at least once during an hour long of uninterrupted coding unless you can do it without getting fatigued.

I suggest looking into the Pomodoro Technique if you need an alternative approach. It's a great way to schedule your breaks and get work done in short bursts.

What should you do during your break? A lot of people use their breaks to exercise. Going on walks, running around outside, or even doing pull-ups/push-ups can help get some blood flowing and oxygen into your brain. Other options include reading a book for pleasure (not related to any programming/coding), listening to music, meditating, or just relaxing with friends.

3. Rotate between different subjects

If you want to become a versatile self-taught developer, it's important to rotate between different concepts/subjects. If you're not good at one concept/subject, then switch to another(but don't switch too often; you need to stick with a plan).

Rotate

The more diverse your knowledge base is, the more likely you are to be able to handle any problem that comes up in your career as a developer.

4. Be consistent, not rigid

It's important to be consistent and not rigid when it comes to your study schedule. A good way to do this is by switching up your study/practicing sessions, making sure you're staying focused, and setting a schedule in place for yourself. If you're working/learning through the materials in a particular order, then stick with that order; but if it feels more natural for you to move around from section-to-section or chapter-to-chapter, then go ahead! Just be sure that when you stop studying each topic or section again before moving on, there's always some kind of structure in place—even if just a rough outline of what will happen next time around.

consistant

This tip also applies when rotating and switching between different programming subjects/concepts: if one method works well for one type of material but not another type, try using other methods until something clicks!

5. Make it fun

You are learning something new and it's not easy. So if you ever find yourself struggling with a particular topic or technique, take a break. This is a learning process and if you are not enjoying yourself it can be difficult to keep going on. If you're having trouble focusing due to massive distractions, consider listening to different songs or watch some movies until your interest in coding returns back to normal!

Fun

6. Use spaced repetition to reinforce learning

One of the best ways to learn something is by reviewing it at increasing intervals. This technique involves repeating and reviewing/re-learning material for a short time period, usually 30 to 60 minutes, before performing an exercise that tests your ability to recall what you learned.

The idea behind spaced repetition is that it helps you remember things longer by forcing you to use the information in your head rather than on paper or screen. If a piece of information isn't used often enough (or at all) in the first place then it won't get stored properly and will be forgotten completely when you need it later on!

Spaced Repeat

For example, if you have a list of 10 new concepts to learn, start by reviewing/re-learning them every day for 30 minutes. When that becomes easy try increasing it to 45 and then 60 minutes before doing an exercise that tests your ability to recall what was learned. It's almost like magic! Spaced repetition can be beneficial in any situation when there is a lot of new information to absorb.

7. Review progress and adjust plans accordingly

Once you've figured out your goals and what you can do, it's time to figure out how much time is needed for them. If you want to become a successful developer, there are three things that will help:

Keep track of your progress and adjust plans accordingly.
Focus on what you are good at (and work on improving weaknesses). This means focusing on one skill at a time; don't try to learn everything all at once!
Explore new topics by researching online resources, asking other people/friends about their experiences with similar problems/needs as yours, or looking up information from google or books that could help guide your learning process. You may also want to start with simpler topics first so that if something gets too difficult later on down the line then there won't be any big surprises when they happen!
Review progress
If at all feasible, focus on developing your strengths before attempting anything new. It is preferable to concentrate on your strengths rather than trying to fix your weaknesses. Don't be concerned about any areas of development that aren't your strong suit!

8. Take notes by hand to learn more deeply

Taking notes is one of the most efficient ways to learn new material. You can do this by hand or on your computer. In either case, taking notes reinforces what you're learning and helps you remember it better than reading alone would.

Take note

When I was in college and preparing for my final examinations, my favorite teacher gave us a task: write down everything we learned in each class so that we would have a record of where our knowledge was at any given time. It was a fantastic self-reflection and timeline-making activity, but more importantly for me personally—since I had never done this before—writing down the concepts helped me grasp them better than just hearing about them from memory alone!

9. Focus on understanding the theory rather than memorizing code

If you want to become a self-taught developer, it's important that you focus on learning the theory behind coding rather than memorizing code.

You can better understand the code if you grasp the theory behind it. You won't need to read through every line of code and examine how each function operates separately if you have a solid understanding of what's going on behind the scene, which will also make it simpler for you to comprehend why certain things are done in particular ways. This can be especially beneficial if there is a particular characteristic of your chosen language or framework that makes mastering some aspects of it first challenging (like if there are multiple ways of doing something). The massive benefit of learning theory is that it will improve your understanding of the code. If you know how to accomplish something but forget how, it will be simpler to figure it out again because you will have a greater understanding of why specific things operate the way they do.

It's much more efficient in terms of time spent learning new things when they're broken down into smaller chunks than if they were presented all at once as one big wall of text!

Theory

All of these hacks and techniques can be used to hone your skills.
The most effective method of learning is by doing, and that's exactly what you're going to do. As a self-taught developer, there are various ways to practice your abilities, but the most crucial thing is that you put the effort in and keep at it. The more often you practice these techniques and builds, the better your understanding will become. It's also crucial to remember that it's alright when something doesn't go according to plan for whatever reason! Learning from mistakes helps us improve our overall productivity as developers since we can pinpoint what went wrong and prevent repeating the same mistakes in future projects or iterations on existing ones.

****Conclusion
Becoming a self-taught developer is not easy. There are many hurdles to overcome and it takes time to learn the skills that will help you become a successful developer. However, it is feasible! With these tips from the hacks & tips outlined above, I hope you will have some success in your journey toward becoming a successful self-taught developer.

This thought is taken from Pramit Marattha

[Redis Hackathon Submission Post Placeholder Title]

Vishal Yadav — Fri, 19 Aug 2022 04:41:34 +0000

Overview of My Submission

Submission Category:

[Optional: Video Explainer of My Project]

Language Used

Link to Code

BTW, your Github code’s README file should contain the details as per this template.

Additional Resources / Info

[Note:] # (Be sure to link to any open source projects that are using your workflow!)

[Note:] # Screenshots/demo videos are encouraged!

Collaborators

[Reminder]: # (Submissions are due on August 29th, 2022 @ 11:59 PM UTC).

Check out Redis OM, client libraries for working with Redis as a multi-model database.
Use RedisInsight to visualize your data in Redis.
Sign up for a free Redis database.

How to remove the tag color and underline

Vishal Yadav — Sun, 07 Aug 2022 14:05:34 +0000

a{
all:unset;
text-decoration:none;
}

all:unset this property is used in anchor tag to remove the color from the anchor tag sentence.
text-decoration:none; this property is used to remove the underline from the sentence.

Buffer in node.js

Vishal Yadav — Fri, 04 Feb 2022 16:54:32 +0000

Buffer Stream and binary data in nodejs

mechanism for reading or manipulating stream of binary data the buffer class was introduced as part of the Nodejs API to make it possible to interact with ctet stream in the context of things like TCP stream and file system operations
The buffer class was introduced as part of the Node.js API to make it possible to manipulate or interact with streams of binary data.
if I want to convert the "L" character into the string "L".charCodeAt(0)-->76
this can happen because of character sets are already define.
One of the definition for character encoding is the UTF-8.
this states that character should be encoded in bytes. a byte is set of eight bits

Stream of Data :

Stream in Nodejs means that sequence of data being moved from one point to other point over a time. means that you have a huge amount of data to process.
if the process is consuming the data faster than it arrives the few data that arrive earlier need to wait for a certain amount of data to arrive before being sent out for processing.
and that waiting area is called buffer it is small physical location in your computer , usually in the RAM where data are temporally gathered wait and are eventually sent out for the processing during streaming
In whatever the case may be, there is always a waiting place. That is the Buffer to Node.js! Node.js can’t control the speed or time of data arrival, the speed of the stream. It only can decide when it’s time to send out the data. If it’s not yet time, Node.js will put them in the buffer — the “waiting area” — a small location in the RAM, until it’s time to send them out for processing.

Interacting with buffer

Happy Coding

Asked Question In MERN Interview

Vishal Yadav — Wed, 26 Jan 2022 12:21:32 +0000

Official Definition :

Node.js is an open-source cross-platform server-side runtime environment built on Chrome’s V8 JavaScript engine, which executes JavaScript code outside of a web browser.

What is node js?

When we write the JavaScript code and run it in browser it runs perfectly but what if you want to run it on server(your computer) and not in some browser.
then Nodejs come into the picture.
And Nodejs give a runtime environment for your JavaScript
Actually Nodejs used the same engine as that of chrome browser.

It is a JavaScript runtime built on Google Chrome V8 Javascript engine.

What is Javascript runtime?

Javascript runtime is a place where we can execute our javascript code
it is like a container or enviroment where we can execute there code
simply we write javascript code and run into the browser then browser internally using the V8 javascript engine and give the run time environment and this engine is nothing but a program that execute your javascript code
but if see that browser is the place where we cana run our javascript code in the browser, but we know that internally browser using the javascript V8 engine
then we talk about that what is this.

What is javascript engine?

Javascript engine is program that execute the js code .It is like a container or environment where js code executed.
chrome : used the V8 javascript engine
Mozilla Firefox : used the Spidermonkey
Internet Explorer : Chakra to execute the code
When we talk about the run javascript to other than browser then nodejs come into the picture.
So we let's we talk about the
So nodejs is place where we can execute our javascript code it is like a container or environment where we can run our js code.
It is used the V8 engine to execute the js code and this engine is also use by the Google chrome browser.
Node js Allow to execute the javascript code outside the browser.
it help to build strong, scalable, secure web application .
It is most popular platform which used to build the backend of webapplication.it can also help to build the RESTFULL API.
The best thing about the Nodejs is that it is open source platform so if you face any problem solution is already given to the Stackover flow

When we used this nodejs?

When we have large data set then we used the nodejs for example video streaming apps,chat application and real-time application.
we also know that nodejs is also called as asynchronous event-driven javaScript runtime then we can not understand some time what is ,means that
asynchronous means that not a particular sequence for executing the tasks when ever the I/O is free it will execute the task accordingly
Happy coding

How to push the Project into the git repo.!

Vishal Yadav — Wed, 26 Jan 2022 10:21:51 +0000

Solution

Create repo into the GitHub profile

Then type the command in sequential order.
first create .gitignore file and then

 git init

 git add .

- git commit -m "Initial commit"

- git remote add origin path http

- git branch -m main

- git push -u origin main

how to remove git from project

rm -rf .git