DEV Community: Black-Thor

Amazon EC2 Instances for Your Cloud Computing Needs

Black-Thor — Sat, 09 Dec 2023 22:11:22 +0000

Amazon Elastic Compute Cloud (EC2) is a powerful service for launching virtual servers on Amazon Web Services (AWS).
These instances are the building blocks for deploying a wide range of applications, including web servers, databases,etc...

To effectively use the power of EC2, it's importantn to understand the different instance types and how to choose the right one for your specific needs.

Instance Types: A Diverse Spectrum of Computing Power

EC2 instances come in a variety of flavors, each tailored to specific use cases.
These types are categorized :

General Purpose Instances:

These instances offer a balanced combination of compute, memory, and networking resources, making them adapted for a wide range of applications.

Compute Optimized Instances:

These instances excel at running CPU-intensive tasks, such as batch processing, media transcoding.

Memory Optimized Instances:

These instances prioritize memory performance, making them ideal for applications that process large data sets in memory.

Storage Optimized Instances:

These instances are designed for workloads that require read and write access to very large data sets on local storage.

Accelerated Computing Instances:

For workloads that demand exceptional processing power, accelerated computing these instances provide access to hardware-based compute accelerators like GPUs.

Amazon EC2 instance names follow a specific naming convention to help you easily identify their characteristics.

The first letter of the instance name indicates the instance family.

The second value represents the instance generation, and it's followed with the architecture a for AMD , g for graviton ( ARM architecture)

After the generation letter, additional letters indicate specific instance configurations, such as processor type (e.g., d for instance store volumes, n for network optimization, b for block storage optimization, e for extra storage or memory, and z for high frequency).

Lettre	Description
d	Instance store volumes
n	Network optimization
b	Block storage optimization
e	Extra storage or memory
z	High frequency

After the dot is a description of the capacity, which determines the number of vCPUs and the amount of memory available for the instance.
These capacities are generally identified by a combination of letters and numbers.

Here are some examples of AWS instance nomenclatures:

M5.large large M5 instance, with 2 vCPUs and 8 GiB of memory.
M5.xlarge: xlarge M5 instance, with 4 vCPUs and 16 GiB of memory.
M5.2xlarge: 2xlarge M5 instance, with 8 vCPUs and 32 GiB of memory.

To summarize, if I take the "m5d.24xlarge" instance

M is the family name.
5 is the generation.
d Use a NVME SSD
24xlarge means it has 24 times more vCPUs than the large .

LeafLet Map

Black-Thor — Sun, 21 May 2023 10:15:47 +0000

Hello,
I'm going to present you how I created a simple map with the leaflet extension.
It allowed me to display a set of bike stations in the city of Lyon in France and to display custom tracks.

What was the objective?

The objective was to have two buttons, to be able to display all the bike stations of the city of Lyon and routes from geoJson files.

So I started by writing those button in HTML :

After defining the buttons of my choice.
I needed to create a simple and JavaScript compatible map. To do this I found Leaflet.

Installing a Leaflet Map:

It was a simple task, I just followed the instruction here: https://leafletjs.com/examples/quick-start/

Configuring the map

You can discover several choices of maps that can be integrated on Leaflet here :
https://leaflet-extras.github.io/leaflet-providers/preview/ on the site, I chose the CartoDB_Positron and imported it.

Once the map is chosen, we can add some basic options, so the initial coordinates when loading the map and the zoom is the city of Lyon in France

Layers are the options to add markers on the map.
So I chose to create 2 layers, one for my bike position and one for my routes

Some jQuery

I know that jQuery is not very optimized or efficient, but I found it very suitable for the 20 lines of code I needed to detect the use of buttons on my site

In the first choice, my code only runs when a choice is validated, it will call the "roadFetch" function passing the name of the necessary API route :

In the second option my code will only run when the user will interact with my button dedicated to bike stations, it will call the function "mapFetch" passing the name of the necessary API route:

API Calls:

In order to facilitate a delivery on a production environment, I added in the HTML an option which allowed me to modify the source of my API calls.

So I created a variable that will react only if the term "production" is written, I added that in a script tag

I also imported my JS file :

And here is how I created my 2 functions that make a call according to the environment. And I create the markers according to the data received from the API :

To customize each marker, there are properties in the data to differentiate each marker, for example: a name, an address...

How to import a custom icon :

The particularity of Leaflet is that it is necessary to define a point of anchoring of the icons and the pop-ups otherwise the display is distorted, here are my choices which allow a correct display:

Here I define and create my new icons :

Leaflet allows customizing the markers, to do this, I went to my data to find the necessary code

How to empty the layers:

How I created the API :

To create an API for this map, I used Express.js:
I initialized the API by allowing corns in the server.js file

I created 2 routes, the first one for the data in points and the second one for the layouts:

For my bike stations, I created a specific path "Station" :
To start I call my router, and I define my files in variable while calling the "fs" module of Node.js

This function that I export on the way to my API:

For my second route, here is how I created it :

And this is how I created this simple map with an API.

If you want to try it, you can download the code on GitHub : website and for the API
You just need Node.js for running the API.

I hope you find some pleasure or help by reading this article.

[week2] Days 1 - JS data structure part 2

Black-Thor — Tue, 01 Feb 2022 12:05:45 +0000

After some time with a lot of problems , i am still in the way to improve my self . I dont reset because i only make 1 week in the 100 day of code .
So back to business , this is what i learned today

Copy an Array with the Spread Operator

You can copy easily the content of another array with this method:

let thatArray = [...thisArray];

Combine Arrays with the Spread Operator

You can put in a specific place your new data by using your spread operator in the middle of an array .

let thisArray = ['sage', 'rosemary', 'parsley', 'thyme'];

let thatArray = ['basil', 'cilantro', ...thisArray, 'coriander'];

Check For The Presence of an Element With indexOf()

indexOf() takes an element as a parameter, and when called, it returns the position, or index, of that element, or -1 if the element does not exist on the array.

let fruits = ['apples', 'pears', 'oranges', 'peaches', 'pears'];

fruits.indexOf('dates');//-1
fruits.indexOf('pears');//2

Iterate Through All an Array's Items Using For Loops

You can use iteration to move in a multidimensional array and use indexOf() like this

function filteredArray(arr, elem) {
  let newArr = [];
  // Only change code below this line
  for ( let i=0 ; i<arr.length; i++){
    if (arr[i].indexOf(elem) == -1) {
      newArr.push(arr[i]); 
}
  }
  // Only change code above this line
  return newArr;//[[10, 8, 3], [14, 6, 23]]
}

console.log(filteredArray([[10, 8, 3], [14, 6, 23], [3, 18, 6]], 18))

Create complex multidimensional arrays

One of the most powerful features when thinking of arrays as data structures, is that arrays can contain, or even be completely made up of other arrays. We have seen arrays that contain arrays in previous challenges, but fairly simple ones. However, arrays can contain an infinite depth of arrays that can contain other arrays, each with their own arbitrary levels of depth, and so on. In this way, an array can very quickly become a very complex data structure, known as a multi-dimensional, or nested array. Consider the following example:

let nestedArray = [
  ['deep'],
  [
    ['deeper'], ['deeper'] 
  ],
  [
    [
      ['deepest'], ['deepest']
    ],
    [
      [
        ['deepest-est?']
      ]
    ]
  ]
];

The deep array is nested 2 levels deep. The deeper arrays are 3 levels deep. The deepest arrays are 4 levels, and the deepest-est? is 5.

Add Key-Value Pairs to JavaScript Objects

At their most basic, objects are just collections of key-value pairs. In other words, they are pieces of data (values) mapped to unique identifiers called properties (keys). Take a look at an example:

const tekkenCharacter = {
  player: 'Hwoarang',
  fightingStyle: 'Tae Kwon Doe',
  human: true
};

add property

tekkenCharacter.origin = 'South Korea';

You can add this property with bracket notation by doing:

tekkenCharacter['hair color'] = 'dyed orange';

Without quotes, it will be evaluated as a variable and the name of the property will be whatever value the variable is. Here's an example with a variable:

const eyes = 'eye color';

tekkenCharacter[eyes] = 'brown';

at the end this is the final result

final result 
{
  player: 'Hwoarang',
  fightingStyle: 'Tae Kwon Doe',
  human: true,
  origin: 'South Korea',
  'hair color': 'dyed orange',
  'eye color': 'brown'
};

Modify an Object Nested Within an Object

Inside a nested object, you can modify the data by specifying what you want to change

let nestedObject = {
  id: 28802695164,
  date: 'December 31, 2016',
  data: {
    totalUsers: 99,
    online: 80,
    onlineStatus: {
      active: 67,
      away: 13,
      busy: 8
    }
  }
};

nestedObject.data.onlineStatus.busy = 10; //modification

Access Property Names with Bracket Notation

You can get the data inside an object like this

let inventory = foods[selectedFood];

Use the delete Keyword to Remove Object Properties

You can delete the data inside an object like this

delete foods.apples;

Check if an Object has a Property

One uses the hasOwnProperty() method and the other uses the in keyword. If we have an object users with a property of Alan, we could check for its presence in either of the following ways:

users.hasOwnProperty('Alan');
'Alan' in users;

Iterate Through the Keys of an Object with a for...in Statement

Sometimes you may need to iterate through all the keys within an object. This requires a specific syntax in JavaScript called a for...in statement. For our users object, this could look like:

for (let user in users) {
  console.log(user);
}

New training site

I discover a website where I can test what I have learned so far, it's : https://exercism.org/ .
I will try to do some exercise a write about it
Today i have done :
JavaScript - Lucian's Luscious Lasagna , it's about creating function and variable

PS:

if you see any spelling or grammar mistakes, can you notify me (I am still improving my English) ? thank you !
if you have any tips for improving my post feel free to comment on the po

My School DevOps Project [part 1] - Jenkins

Black-Thor — Mon, 17 Jan 2022 23:35:21 +0000

Introduction

Hello, so for my DevOps module in my school we add a really complete DevOps Project using AWS EC2 options and I founded it fascinating, so I decided to publish how i made it, with some alternative using vagrant instead of AWS. This presentation is separated in different part. This is the first part talking about Jenkins

Simple Jenkins CI pipeline, the mission was to :

Pull a git repo
Start Unitary and integration test
Drop the jar file on the Jenkins workspace

Constraints :
The pipeline should have the following parameter :

BRANCH: String to choose the repo branch
SKIP_TESTS: A boolean to control the execution of some test
VERSION_TYPE: SNAPSHOT or RELEASE (rename jar file )
VERSION: a string for the jar version (ex: SB3T-1.0-SNAPSHOT)

Deploy Jenkins

Why dockerize my project ?

I want my project easy to build and destroy so i can work whenever i want and easily , i was using also vscode with the plugin for launching vscode in wsl on my computer . WSL with docker make possibility to change file while docker is running to test new elements

Tools to make it :

Docker Desktop
WSL
plugin 'remote wsl' for vs code

Docker Compose and Dockerfile

So for making this project work we need to set up a Dev Environment, I was using docker-compose and dockerfile, so i put my docker compose and Dockerfile in the root of my project for allowing me to import future feature easily.

├── Docker-compose.yml
├── Dockerfile
├── jenkins
│   ├── conf
│   │   ├── plugins.txt
│   │   ├── jenkins.yaml
│   │   └── jobs
│   │       ├── sb3t_wrapper.groovy
│   │       ├── jobs.groovy
│   │       ├── folders.groovy
│   └── jenkins.md

Docker-compose.yml

Inside my docker file I create a Jenkins service, this service is running on port 80 and 50000 on my localhost computer port
This creates different folder in /var directory in docker, importing some file like ./jenkins/conf in /var/jenking_config
This Jenkins services as an admin user because it's only for personal use do not do that on production ◑____________◑ , So this is bind with just admin admin and run on, HTTP protocol on the port 8081 on docker environment .

---
version: '3.8'

services:
  jenkins:
    build:
      context: .
    ports:
      - 80:8081
      - 50000:50000
    volumes:
      - jenkins_home:/var/jenkins_home
      - ./jenkins/conf:/var/jenkins_config/
      - #./terraform:/var/terraform usefull later 
      - #./ansible/:/var/ansible  usefull later 

    environment:
      - CASC_JENKINS_CONFIG=/var/jenkins_config/jenkins.yaml
      - JENKINS_ADMIN_ID=admin
      - JENKINS_ADMIN_PASSWORD=admin
      - JENKINS_OPTS="--httpPort=8081"

volumes:
  jenkins_home:

The Docker File

The purpose of this docker file is to import/create the images and the volume for my Jenkins to run properly, it installs all the necessary features and the future one like Ansible .

FROM jenkins/jenkins:lts-jdk11

# Disable setup wizard
ENV JAVA_OPTS -Djenkins.install.runSetupWizard=false -Dpermissive-script-security.enabled=true

USER root
RUN apt-get update && \
    apt-get -y install apt-transport-https \
      ca-certificates \
      curl \
      gnupg2 \
      software-properties-common && \
    curl -fsSL https://download.docker.com/linux/$(. /etc/os-release; echo "$ID")/gpg > /tmp/dkey; apt-key add /tmp/dkey && \
    add-apt-repository \
      "deb [arch=amd64] https://download.docker.com/linux/$(. /etc/os-release; echo "$ID") \
      $(lsb_release -cs) \
      stable" && \
   apt-get update && \
   apt-get -y install docker-ce
#installation terraform
RUN curl -fsSL https://apt.releases.hashicorp.com/gpg | apt-key add - && apt-add-repository "deb [arch=amd64] https://apt.releases.hashicorp.com $(lsb_release -cs) main" && apt-get update && apt-get install terraform

#install ansible
RUN apt-get install python3-pip -y && \
  pip3 install ansible 
#install boto3 for inventory dynamic
RUN pip3 install boto3
#Install LVM for lvol and lvg volumes
RUN ansible-galaxy collection install community.general
# Load plugins w jenkins-plugin-cli
COPY --chown=jenkins:jenkins jenkins/conf/plugins.txt /usr/share/jenkins/ref/plugins.txt
RUN jenkins-plugin-cli -f /usr/share/jenkins/ref/plugins.txt

USER jenkins

Jenkins pipeline

Using Declarative Jenkins

Declarative pipeline is a relatively new feature that supports the pipeline as code concept. It makes the pipeline code easier to read and write. This code is written in a Jenkinsfile which can be checked into a source control management system such as Git. pipelines are based on the groovy DSL, the scripted pipeline uses stricter groovy based syntaxes because it was the first pipeline to be built on the groovy foundation. Since this Groovy script was not typically desirable to all the users, the declarative pipeline was introduced to offer a simpler and more optioned Groovy syntax. more on This site

Jenkins.Yaml

here you can fin the origin of this jenkins.yaml

This setup Your Jenkins with some option, with this jenkins yaml you install some tools usefull to test the code and respond to the project.

It's installing :

Git
Java
Maven with a specific version

---

jenkins:
  numExecutors: 1
  systemMessage: "Hi, jenkins setup with jcasc"
  securityRealm:
    local:
      allowsSignup: false # prevents anonymous users from creating an account through the web interface
      users:
        - id: ${JENKINS_ADMIN_ID}
          password: ${JENKINS_ADMIN_PASSWORD}

  authorizationStrategy:
    globalMatrix:
      permissions:
        #- "View/Delete:authenticated"
        #- "View/Read:authenticated"
        #- "View/Configure:authenticated"
        #- "View/Create:authenticated"
        - "Job/Read:authenticated"
        - "Job/Build:authenticated"
        - "Job/Configure:authenticated"
        - "Job/Create:authenticated"
        - "Job/Delete:authenticated"
        - "Job/Discover:authenticated"
        - "Job/Move:authenticated"
        - "Job/Workspace:authenticated"
        - "Job/Cancel:authenticated"
        - "Run/Delete:authenticated"
        - "Run/Replay:authenticated"
        - "Run/Update:authenticated"
        - "Overall/Read:admin"
        - "Overall/Administer:admin"

  crumbIssuer: "standard"

  # Docker: https://github.com/jenkinsci/configuration-as-code-plugin/tree/master/demos/docker
  clouds:
    - docker:
        name: "docker"
        dockerApi:
          dockerHost:
            uri: "unix:///var/run/docker.sock"
        templates:
          - labelString: "docker-agent"
            dockerTemplateBase:
              # TODO: pin sha256 or versions when using in production
              image: "jenkins/agent"
            remoteFs: "/home/jenkins/agent"
            connector:
              attach:
                user: "jenkins"
            instanceCapStr: "10"
            retentionStrategy:
              idleMinutes: 1

security:
  scriptApproval:
    approvedSignatures:
      - method java.lang.String indexOf int
      - method io.jenkins.plugins.casc.ConfigurationAsCode configure
      - staticMethod io.jenkins.plugins.casc.ConfigurationAsCode get
tool:
  git:
    installations:
      - home: "git"
        name: "Default"
  jdk:
    installations:
      - home: "/opt/java/openjdk"
        name: "java"
  maven:
    installations:
      - name: "maven"
        properties:
          - installSource:
              installers:
                - maven:
                    id: "3.6.2"


jobs:
  - file: /var/jenkins_config/jobs/folders.groovy
  - file: /var/jenkins_config/jobs/jobs.groovy

You can import some jobs , by configuring git in your jenkins yaml file , here i specify 2 file a specific directory

How to import Jobs in Docker / Jenkins

The first file i import setup two different directory in my jenkins app , the CI and the CD directory

#!groovy
/**
 * Setup folders
 */

folder('CI')
folder('CD')

After The file setups , the jenkins yaml file import the second file , println is used to print out some information , for importing i need to define my pipeline and specify the root to this pipeline .

Once I have define my pipeline , i add the different required parameters wich gonna have there important role on how gonna work this piepline

#!groovy
println('---------------------------------------------------------------------------Import Job CI/sb3t')
// define first pipeline 
def pipelineScript = new File('/var/jenkins_config/jobs/sb3t_wrapper.groovy').getText("UTF-8")
//Adding pipeline to the right path 
pipelineJob('CI/sb3t_wrapper'){
    description("Build .jar file from sb3t repository , from master branch")
//Importing parameter 
    parameters {
        stringParam {
            name('BRANCH')
            defaultValue('master')
            description("branch to pull")
            trim(false)
        }
        booleanParam {
            name('SKIP_TEST')
            defaultValue(true)
            description("Skip test")
        }
        choice {
            name('VERSION_TYPE')
            choices(['SNAPSHOT', 'RELEASE'])
            description('Version type between snapshot and release')
        }
        stringParam {
            name('VERSION')
            defaultValue('1.0')
            description("version of the project")
            trim(false)
        }
    }
//Importing the script in sandbox 
    definition{
        cps {
            script(pipelineScript)
            sandbox()
        }
    }
}

Usage of Jenkins pipeline

with the parameters define in my jobs.groovy file , i can script what am i importing in my jenkins pipeline . By using the declarative pipeline method i know and i can use all the parameters i have defined earliers .

#!groovy

pipeline {
//use any agent installed 
    agent any
    tools {
        // Install the Maven version configured as "M3" and add it to the path.
        maven 'maven'
    }
    environment {
        TEST = 'TEST'
    }
    options {
        buildDiscarder(logRotator(numToKeepStr: '100'))
    }

    stages {
        stage('Git clone') {
            steps {
//choosing the branch
                git branch: "${params.BRANCH}", url: '<sping boot project on github>'
            }
        }


        stage('Compiling') {
            steps {
                    sh 'mvn compile'
            }
        }
        stage('Testing'){
            when {
//using skip parameter

            expression { params.SKIP_TESTS == false }
            }
            steps {
                sh 'mvn test'
            }
        }

        stage('Package') {
            steps {
                script {
                    sh 'mvn package'
                }
            }
        }

        stage('Verify') {
               when {
//using skip parameter
            expression { params.SKIP_TESTS == false }
            }
            steps {
                sh 'mvn verify'
            }
        }


        stage('Package version ') {
            steps {
//using version parameter
                sh "mvn versions:set -DnewVersion=${params.VERSION}-${params.VERSION_TYPE}"
//using skip parameter

                sh "mvn clean package  -DskipTests=${params.SKIP_TESTS}"
            }
        }

        stage('archive') {
            steps {
//create archive in a artifacts with .jar

                archiveArtifacts(artifacts: '**/*.jar', followSymlinks: false)
            }
        }

    }
}

Run

For running the project i can type docker-compose up --build or docker-compose up -d to create my service and go to http://localhost/ page for accessing my jenkins pipeline

You want to try the project, get it on my GitHub page (Posted after my notation)

PS:

if you see any spelling or grammar mistakes, can you notify me (I am still improving my English) ? thank you !
if you have any tips for improving my post feel free to comment on the post
and i hope you enjoy reading this

nb :
plungin.txt for jenkins

bouncycastle-api:2.23
github:1.34.0
ws-cleanup:0.39
branch-api:2.6.5
pipeline-build-step:2.15
trilead-api:1.0.13
popper-api:1.16.1-2
pipeline-rest-api:2.19
credentials-binding:1.27
git-client:3.9.0
build-timeout:1.20
resource-disposer:0.16
oauth-credentials:0.4
email-ext:2.83
pipeline-model-extensions:1.9.1
ssh-credentials:1.19
handlebars:3.0.8
durable-task:1.39
lockable-resources:2.11
github-branch-source:2.11.2
pipeline-stage-tags-metadata:1.9.1
jquery3-api:3.6.0-2
jsch:0.1.55.2
git-server:1.10
ace-editor:1.1
junit:1.52
workflow-api:2.46
cloudbees-folder:6.16
bootstrap4-api:4.6.0-3
font-awesome-api:5.15.4-1
jackson2-api:2.12.4
pipeline-graph-analysis:1.11
credentials:2.5
snakeyaml-api:1.29.1
pipeline-input-step:2.12
git:4.8.2
dashboard-view:2.17
docker-java-api:3.1.5.2
pam-auth:1.6
structs:1.23
async-http-client:1.9.40.0
docker-commons:1.17
pipeline-model-definition:1.9.1
dockerhub-notification:2.5.2
github-api:1.123
token-macro:266.v44a80cf277fd
command-launcher:1.6
workflow-durable-task-step:2.39
workflow-basic-steps:2.24
popper2-api:2.9.3-1
pipeline-milestone-step:1.3.2
plain-credentials:1.7
apache-httpcomponents-client-4-api:4.5.13-1.0
workflow-cps:2.93
ldap:2.7
docker-plugin:1.2.3
ssh-slaves:1.33.0
ssh-agent:1.23
okhttp-api:3.14.9
caffeine-api:2.9.2-29.v717aac953ff3
antisamy-markup-formatter:2.1
jaxb:2.3.0.1
momentjs:1.1.1
docker-build-step:2.8
jdk-tool:1.5
workflow-support:3.8
matrix-auth:2.6.8
pipeline-stage-step:2.5
plugin-util-api:2.4.0
build-name-setter:2.2.0
pipeline-stage-view:2.19
pipeline-github-lib:1.0
workflow-aggregator:2.6
gitlab-plugin:1.5.20
echarts-api:5.1.2-11
workflow-cps-global-lib:2.21
workflow-multibranch:2.26
timestamper:1.13
workflow-step-api:2.24
sshd:3.1.0
checks-api:1.7.2
workflow-job:2.41
authentication-tokens:1.4
pipeline-model-api:1.9.1
mailer:1.34
copyartifact:1.46.1
workflow-scm-step:2.13
jjwt-api:0.11.2-9.c8b45b8bb173
matrix-project:1.19
scm-api:2.6.5
bootstrap5-api:5.1.0-3
ssh:2.6.1
display-url-api:2.3.5
configuration-as-code:1.53
job-dsl:1.77
ansicolor:1.0.0

[week2] Days 1 - JS data structure

Black-Thor — Mon, 17 Jan 2022 21:59:09 +0000

Back for 100 days of code

After 1 week without the ability to post because I got electrical trouble in my house, I follow my ways through JS learning course on freeCodeCamp.

Basic Data Structure

Data structures, at a high level, are techniques for storing and organizing data that make it easier to modify, navigate, and access. Data structures determine how data is collected, the functions we can use to access it, and the relationships between data.

The most basic of all data structures, an array, stores data in memory for later use. Each array has a fixed number of cells decided on its creation

How to manipulate

Use an Array to Store a Collection of Data

You can use let to make an array which store data,
example on a one dimensional array :

let simpleArray = ['one', 2, 'three', true, false, undefined, null];

array can store complex object with multidimensional array

Access an Array's Contents Using Bracket Notation

You can access your data in your array.
In an array, each array item has an index. This index doubles as the position of that item in the array, and how you reference it
int's important to not forget that JavaScript is a zero-indexed, meaning that the first element of an array is actually at the zeroth position this is how to retrieve data :

let ourVariable = ourArray[0];
how to add a variable iin the array 
ourArray[1] = "not b anymore";

Add Items to an Array with push() and unshift()

Array.push() to add an element to the end of an array
Array.unshift() to add the element to the beginning
you can pass a variable with these two methods, but not array

Remove Items from an Array with pop() and shift()

pop() removes an element from the end of an array,
shift() removes an element from the beginning.

You cannot parameter with this two method and u can change only array

Remove Items Using splice()

splice() allows us to remove any number of consecutive elements from anywhere in an array.

let array = ['today', 'was', 'not', 'so', 'great'];

array.splice(2, 2); //['today', 'was', 'great']
```



### Add Items Using splice()
`splice()` can take up to three parameters, and you can use the third parameter, comprised of one or more element(s), to add to an array.



```JavaScript
const numbers = [10, 11, 12, 12, 15];
const startIndex = 3;
const amountToDelete = 1;

numbers.splice(startIndex, amountToDelete, 13, 14);
console.log(numbers);//[ 10, 11, 12, 13, 14, 15 ]
```



### Copy Array Items Using slice()



```JavaScript

let weatherConditions = ['rain', 'snow', 'sleet', 'hail', 'clear'];

let todaysWeather = weatherConditions.slice(1, 3);//['snow', 'sleet']
```

[week1] Days 7 - first week complete

Black-Thor — Sun, 09 Jan 2022 16:49:06 +0000

Hello, first week successful, the hardest part is done, I managed to work one hour a day on code and make a post on the subject

Now the objective is to maintain the pace and succeed in better structuring my work with precise objectives from day to day .

My Learning Goals for today:

Finish Debuging on freecode camp

What I Learned:

was rather simple but enriching, I could see the typical errors that one can meet when one dev and how to treat them, for example the infinite loop, how to identify them and corrected them

My Goals for Week 2 :

For week 2 i gonna continue this js course on freecodecamp and in the same time i will learn more on node js and express for my school project and try to document my learning

[week1] Days 6 - Learn You Node

Black-Thor — Sat, 08 Jan 2022 17:02:40 +0000

Hello , back for another day of dev.
On day 5 i was working for a school project on node JS, and i was interested to go deeper on my understanding of node JS so i install Learn you Node a fantastique tool for understanding how work node.js and how to use it's potential

My Learning Goals for today:

Finish some learn you node challenge

What I Learned:

By finishing the challenge 7 of the 13 challenge, I understood that there are a lot of useful tools in node JS, like we can manipulate file by using the module 'fs' and I learned how to make a simple server with node.js. I really recommend you to try 'learn you node' and maybe you will discover some new feature !

My Goals for Day 7:

For day 7, i will continue the freecodecamp course on javascript , and try to do at least 2 section

[week1] Days 5 - I call jenkins API with a express app

Black-Thor — Fri, 07 Jan 2022 19:49:33 +0000

School Project

So today i was working on a school project , and i made a call api consumption from my express app to a jenkins REST API

Context

We're making an api with node.js / Express , this call the api of Jenkins for getting the result of a job

.env

For making this API we use a .env file wich contain the data necessary to access jenkins, like the user or the token link to the user, we define it like this.

JOB_USER = <jenkins_user>
JOB_TOKEN = <jenkins_token>

JENKINS_URL = <Jenkins url>

Create express server

For insure that our api run proprelie , we created an application/server. You can find information on how to make one here

Jenkins Api Call

We make options for gettings informations from our .env like this

let options = {
    url : "",
    method: 'HEAD',
    auth: {
        'user': process.env.JOB_USER,
        'pass': process.env.JOB_TOKEN
    }
};

now we can make our routage

    app.get("/jenkins", (req,res) => {
        options.url = `${process.env.JENKINS_URL}/job/[you folder]/job/[you job]/lastBuild/api/json?pretty=true`
        request.get(options, (err, response) => {
            if (!err){                
                let status = JSON.parse(response.body)
                res.send(status.result)
            }
            else {
                res.send(err) ; 
            }   
        })
    })

And with that i can now if my build run properly or i faced some trouble .

Thx for reading , hope you loved it !

PS:

if you see any spelling or grammar mistakes, can you notify me (I am still improving my English) ? thank you !
if you have any tips for improving my post feel free to comment on the post

[week1] Days 4 - Mini project around js and regex

Black-Thor — Thu, 06 Jan 2022 17:45:55 +0000

Mini project

Today I made a password verification by following online guides and from the knowledge acquired during the learning of regex , u can find it on codepen.io

I find a real problem

While doing this project I realized how difficult it is to initialize a project so I'm writing it down for later in order to improve this aspect

freeCodeCamp Debbuging

On the freecode camp of the day I discovered a new way to use console to debug my programs

console.clear()
Cleans the contents of the console
console.log(..)
Allows you to display messages in the console. You can use wildcards and additional arguments with this method.
console.debug(..)
You can only see the contents printed by the console.debug(..) method if your Console is set to Log-Level="debug". By default, Log-Level="log"

console.debug(obj1 [, obj2, ..., objN]);
console.debug(message [, subst1, ..., substN]);

console.info(..) Displays an informative message in the browser console. In Firefox and Chrome, a small i icon is displayed in front of the message.

var myObj = {firsname:"John", lastname:"Doe"};
console.info(myObj);/*{firsname: 'John', lastname: 'Doe'}
firsname: "John"
lastname: "Doe"*/

console.warn(..) Writes in the browser console the content of the object in the form of a warning with a warning pictogram in front of the line.

console.warn("First warning");
console.warn("Second warning");

console.error(..)

Writes in the browser console the content of the object in the form of a error with a warning pictogram in front of the line.

console.warn("First error");
console.warn("Second error");

PS:

if you see any spelling or grammar mistakes, can you notify me (I am still improving my English) ? thank you !
if you have any tips for improving my post feel free to comment on the post

[week1] Days 3 - Regex ! part 2

Black-Thor — Wed, 05 Jan 2022 20:56:31 +0000

Busy day !

Today was a complicated day, I managed to work on my regex course, but in a rush that didn't allow me to fully understand the lessons I was learning.

So, to test myself tomorrow, I'm going to realise a mini challenge which consists in the realisation of an application that will check if a password corresponds to the standard of a secure password.

In advance sorry, but the rest of the article is from my personal notes, I do not have the time to edit everything.
But I will detail my creation tomorrow

What did i learn ?

Lazy Matching

let text = "<h1>Winter is coming</h1>";
let myRegex = /<.*?1>/;
let result = text.match(myRegex);//h1

Match Beginning String Patterns

let rickyAndCal = "Cal and Ricky both like racing.";
let calRegex = /^Cal/; 
let result = calRegex.test(rickyAndCal);//Cal

Match Ending String Patterns

let caboose = "The last car on a train is the caboose";
let lastRegex = /caboose$/; // Change this line
let result = lastRegex.test(caboose);//True

Match All Letters and Numbers

/\w/gi

used to count all alphanumeric characters

Character classes

    - \w word \d digit \s whitespace (tabs, line breaks)
    - \W NOT word \D NOT digit \S NOT whitespace
    - \t tabs, \n line breaks
    - . any character (except newline)

Specify Upper and Lower Number of Matches

let ohStr = "Ohhh no";
let ohRegex = /Oh{3,6}\sno/gi; // Change this line
let result = ohRegex.test(ohStr);//true

Specify Only the Lower Number of Matches

/ha{3,}h/

this will match with haaaaaaah not hah

Specify Exact Number of Matches
/a{3}/

Check for All or None

let favWord = "favorite";
let favRegex = /favou?rite/; 
let result = favRegex.test(favWord) // favourite true also

Positive and Negative Lookahead

A positive lookahead will look to make sure the element in the search pattern is there, but won't actually match it. A positive lookahead is used as (?=...) where the ... is the required part that is not matched.
On the other hand, a negative lookahead will look to make sure the element in the search pattern is not there. A negative lookahead is used as (?!...) where the ... is the pattern that you do not want to be there. The rest of the pattern is returned if the negative lookahead part is not present.

let sampleWord = "astronaut";
let pwRegex = /(?=\w{6})(?=\w*\d{2})/; 
let result = pwRegex.test(sampleWord); // match passwords that are greater than 5 characters long, and have two consecutive digits.

Check For Mixed Grouping of Characters

let myString = "Eleanor Roosevelt";
let myRegex = /(Franklin|Eleanor).*Roosevelt/;
let result = myRegex.test(myString);// Eleanor Roosevelt and Franklin Roosevelt both true

Reuse Patterns Using Capture Groups

let repeatNum = "42 42 42";
let reRegex = /^(\d+)\s\1\s\1$/; 
let result = reRegex.test(repeatNum);//find the patern

Remove Whitespace from Start and End

let hello = "   Hello, World!  ";
let wsRegex = /^\s+|\s+$/g; 
let result = hello.replace(wsRegex, "");

PS:

if you see any spelling or grammar mistakes, can you notify me (I am still improving my English) ? thank you !
if you have any tips for improving my post feel free to comment on the post

[week1] Days 2 - Regex !

Black-Thor — Tue, 04 Jan 2022 21:07:14 +0000

Regular expressions, often shortened to "regex" or "regexp", are patterns that help programmers match, search, and replace text. And in my dev journey I never feel like I need to learn regex, because it seemed so difficult to learn.But on my ride to complete the freeCodeCamp course i need to take this regex lessons on freeCodeCamp.

Garabato Kid

My daily code

I have done 13 of the 33 exercise, i have learned the basics of regex and find some ressources to test and getting more info on how to use it .

What did i learn ?

The basic format of a regex is like this :
/ expression / flags, i.e /[A-Z]+/g
You can group your expression by using parentheses (), or you can combine them by using logical OR |, it's possible to affect the search by using flags

In javascript you have multiple ways to use regex the first one is .test()

let testStr = "freeCodeCamp";
let testRegex = /Code/;
testRegex.test(testStr); // true

The second way is to find a matching string with
.match()

const paragraph = 'The quick brown fox jumps over the lazy dog. It barked.';
const regex = /[A-Z]/g;
const found = paragraph.match(regex); //Array ["T", "I"]

Common Regex symbol or flag

Symbol	Meaning
i flag	the search is case-insensitive
g flag	the search looks for all matches
*	Match 0 or more characters
+	Match 1 or more characters
[abc]	Any of a,b or c
[^abc]	not a,b or c
[a-z]	Any letter from a to z
[a-c2-8]	Any letter or number from a to z or from 2 to 8

Usefull Ressources

regexr
regex101 really similar to regexr
MDN Docs
Regular Expressions (RegEx) in 100 Seconds and there cheatsheet
iHateRegex you can find a article on dev.to about it

Thank you for reading this post, hope you loved it 😀

PS:

if you see any spelling or grammar mistakes, can you notify me (I am still improving my English) ? thank you !
if you have any tips for improving my post feel free to comment on the post

[week1] Days 1 - ES6 Modules

Black-Thor — Mon, 03 Jan 2022 20:00:14 +0000

So for my 100 days of code i decided to start with the basic by ending my learning courses on freecodecamp and getting the certification from FreeCodeCamp on JavaScript Algorithms and Data Structures .
I had already started the certification but i leaved it . So i started with the ES6 part , And it was a good choice , i have found some ES6 syntax i didn't know or use .

This is my top 5 thing i learned todays :

Rest Parameter : With the rest parameter, you can create functions that take a variable number of arguments. These arguments are stored in an array that can be accessed later from inside the function.

const sum = (...args) => {
  return args.reduce((a, b) => a + b, 0);
}
console.log(sum(1, 2, 3)); // 6

Spread Operator : which allows us to expand arrays and other expressions in places where multiple parameters or elements are expected.

Math.max.apply(null, arr)

const arr = [6, 89, 3, 45];
const maximus = Math.max(...arr);

Use Destructuring Assignment to Extract Values from Objects

//ES5
const user = { name: 'John Doe', age: 34 };

const name = user.name;
const age = user.age;

//ES6
const { name, age } = user;
```



- Use Destructuring Assignment to Assign Variables from Nested Objects


````javascript
//ES5
const user = {
  johnDoe: { 
    age: 34,
    email: 'johnDoe@freeCodeCamp.com'
  }
};

//ES6
//Here's how to extract the values of object properties and assign them to variables with the same name:
const { johnDoe: { age, email }} = user;
// here's how you can assign an object properties' values to variables with different names:
const { johnDoe: { age: userAge, email: userEmail }} = user;

```
{% endraw %}


- Object Literal Declarations Using Object Property Shorthand
{% raw %}

````javascript
//ES5
const getMousePosition = (x, y) => ({
  x: x,
  y: y
});
//ES6
const getMousePosition = (x, y) => ({ x, y });
```



and many more thing 
On day 2 i will work on [regex ](https://www.freecodecamp.org/learn/javascript-algorithms-and-data-structures/#regular-expressions)

PS:
- if you see any spelling or grammar mistakes can you notify me (I am still improving my English)  ? thank you !
- if you have any tips for improving my post feel free to comment on the post