June 2020 - NinethSense oWnZ mE!

June 28, 2020July 1, 2020

Bash script to backup using lftp

Can use below script to gzip a folder, and upload to a FTP site. We can use a cron task to schedule it.



#!/bin/bash

Fn=myvps-backup-$(date +%Y%m%d).tar.gz

tar cf - websites | gzip -9 - > $Fn  lftp -u user@name,password myhostname.com << EOF

set ssl:check-hostname no

set ssl:verify-certificate false

cd /public_ftp

put $Fn

bye

EOF

June 26, 2020June 26, 2020

A basic JavaScript drawing interpreter

Coding for fun… An attempt to make a fully JavaScript based canvas drawing interpreter in മലയാളം/Malayalam.

Try in action here – https://ninethsense.github.io/code-share/CanvasDrawing/

Source Code:


<html>
    <head>
        <meta http-equiv="content-type" content="text/html; charset=utf-8">
        <style>
            #c {
              display: flex;
                width:100%;
                height:100%;
            }
            #t {
              width:100%;
            }
            .col {
              flex:1;min-height:80%;
              background-color: #eee;
              margin:1px 1px;
            }
            #e {
              font-family: monospace;
              font-weight: bold;
              font-size:12pt;
              caret-color: red;
            }
        </style>
    </head>
    <body>
      <div style="display:flex;min-height:80%;border:solid 1px black;">
        <div id="e" class="col" contenteditable>
          മായ്‌ക്കുക<br>
          രേഖ (ഇടത്=100, മുകൾ=100, വീതി=200, ഉയരം =200)<br>
          വൃത്തം (ഇടത്=200, മുകൾ=200, ആരം=50, നിറം ="പച്ച" )<br>
          ചതുരം (ഇടത്=50, മുകൾ=50, വീതി=300, ഉയരം=200)<br>
          ചതുരം (ഇടത്=50, മുകൾ=50, വീതി=300, ഉയരം=200, നിറം = "ചുവപ്പ്")<br>
          രേഖ (ഇടത്=100, മുകൾ=100, വീതി=200, ഉയരം =300,  നിറം ="#0000ff")
        </div>
        <div class="col">
          <canvas id="c"></canvas>
            <circle cx="50" cy="50" r="40" stroke="green" stroke-width="4" fill="yellow" />
          </svg>
        </div>
      </div>
      
      <input type="button" value="Draw" id="ok" />
      

    <script>
      var c = document.getElementById("c");
      c.width = c.offsetWidth;
      c.height = c.offsetHeight;
      var cx = c.getContext("2d");
      
      document.getElementById("ok").addEventListener("click", function(){
        
        var pgm = document.getElementById("e").innerText;
        var lines = pgm.split("\n");
        
        lines.forEach(function(stmt, i) {
          if (!stmt.trim()) return;
          
          var cmd = stmt.split(/{|\(| /)[0];
          
          var params = stmt.replace(cmd, "" ).replace(/=/g,":").replace(/\(/g,"{").replace(/\)/g,"}");
          

          params = params.replace(/ഇടത്|മുകൾ|ആരം|വീതി|ഉയരം|നിറം/gi, function(matched){
                  return {
                    "ഇടത്":"\"left\"", 
                    "മുകൾ":"\"top\"", 
                    "ആരം":"\"radius\"",
                    "വീതി":"\"width\"",
                    "ഉയരം":"\"height\"",
                    "നിറം":"\"color\""
                  }[matched];
                });
          var col = {"പച്ച":"#00ff00", "ചുവപ്പ്":"#ff0000", "നീല":"#0000ff"};
                
          var j = {};
          try {
            j = JSON.parse( params );
            
          } catch {
            if (cmd != "മായ്‌ക്കുക") {
              Err();
              return;
            }
          }

          if ('color' in j) {
            if (j.color in col) {
              cx.strokeStyle = col[j.color];
            } else {
              cx.strokeStyle = j.color;
            }
          } else {
            cx.strokeStyle = "#000";
          }
          
          cx.beginPath();
          switch(cmd) {
            case "മായ്‌ക്കുക":
              cx.clearRect(0,0,c.offsetWidth,c.offsetHeight);
              break;
            case "വൃത്തം":
              if ( !Number.isInteger(j.left) || !Number.isInteger(j.top) || !Number.isInteger(j.radius)) {
                Err();
              }
                cx.arc(j.left, j.top,j.radius,0, 2 * Math.PI, false);
              break;
            case "രേഖ":
              cx.moveTo(j.left, j.top);
              cx.lineTo(j.width, j.height);
              break;
            case "ചതുരം":
              cx.rect(j.left, j.top, j.width, j.height);
              break;
            default:
              Err();
              break;
          }
          function Err() {
            alert(`Syntax Error in "${cmd}" at line ${i+1}`);
          }

          if (cmd != "മായ്‌ക്കുക") cx.stroke();
          cx.closePath();
        });
      });
      
    </script>
    </body>
</html>

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June 23, 2020

Microsoft Certified: Azure AI Engineer Associate

Took the exam today, and earned the badge.

Microsoft Certified: Azure AI Engineer Associate

June 14, 2020June 14, 2020

Web based single-page, light weight HTML editor with auto-save, using HTML, JavaScript and PHP

Source Code:


<?php
    /**
     *  A lightweight, single page HTML editor with live preview and auto-save
     *  Author: Praveen Nair @ http://blog.ninethsense.com/
     *  
     */

    $f = $fn = "";
    if (count($_GET) == 1)  {
        $f = key($_GET);
        $fn = "$f.html";
    } else {
        die();
    }

     if ( isset($_POST["c"]) )  {
        $content = $_POST["c"];
        echo  (file_put_contents($fn, $content))?"1":"-1";
        die();
    }
   
?>
<html>
    <head>
        <meta http-equiv="content-type" content="text/html; charset=utf-8">
        <style>
            #tb {
                margin-left: 5;
            }
            #editor, #preview {
                flex: 1 0 0;
                background:#eee;
                margin: 5 5;
                padding: 5 5;
                overflow:auto;
            }
            #editor {
                font-family: monospace;
            }
            #preview, a {
                font-family: Arial, Helvetica, sans-serif;
            }
            [placeholder]:empty::before {
                content: attr(placeholder);
                color: #ccc; 
            }
            #saved {
                font-size:8pt;
                margin-left:5px;   
            }
        </style>
    </head>
    <body>
        <div id="tb">
            <input type="button" value="Save" onclick="Save()" /><span id="saved"></span>
            <a href="preview.php?<?=$f?>" target="_blank" style="float:right;font-size:8pt">[Preview]</a>
        </div>
        <div style="display: flex;height:90%">
            
            <div id="editor" contenteditable="true" onkeyup="LivePreview()" placeholder="Your HTML Code"></div>

            <div id="preview" placeholder="Preview Area"></div>
        </div>

        <script>
            var editor = document.getElementById("editor");
            var preview = document.getElementById("preview");
            var IsSaved = true;
            editor.focus();
            function LivePreview() {
                preview.innerHTML = editor.innerText;
                IsSaved = false;
            }
            function Save() {
                var xhttp = new XMLHttpRequest();
                xhttp.onreadystatechange = function() {
                    if (this.readyState == 4 && this.status == 200) {
                        if (xhttp.responseText == "1") {
                            document.getElementById("saved").style.color = 'green';
                            document.getElementById("saved").innerText = "Last saved at " + new Date() ;
                            IsSaved = true;
                        } else {
                            ShowError();
                        }
                    } 
                };
                var formData = new FormData();
                formData.append("c", editor.innerText);
                xhttp.open("POST", "<?= $_SERVER["PHP_SELF"]. "?$f" ?>", true);
                xhttp.send(formData);

            }
            setInterval(() => {
                if (!IsSaved) {
                    Save();
                }
            }, 5000);

            ShowError = function() {
                var ele = document.getElementById("saved");
                ele.style.color = 'red';
                ele.innerText = "Couldn't Auto-save. Will retry soon" ;
            }
            window.onload = function() {
                <?php
                    $content = "";                
                    if ( $_SERVER['REQUEST_METHOD'] != 'POST' ) {
                        if (file_exists($fn)) {
                            $content = file_get_contents($fn);
                        } 
                        echo "editor.innerText = `$content`;";
                    }
                ?>
                LivePreview();
            }
            
        </script>
    </body>
</html>


View in GitHub | Made with wp-showgithubfile plugin

June 13, 2020June 13, 2020

My wp-ShowGithubFile plugin is accepted by WordPress today!

Though I wrote the plugin initially for personal use, now the same is available for you to use in your WordPress sites.

Link: https://wordpress.org/plugins/wp-showgithubfile/

You can either download it from the directory, or install directly within your WordPress installation. Here is a live demo of the plugin:


package com.company;

import java.util.Arrays;

public class Main {

    public static void main(String[] args) {

        // New Customer wants to buy a bottle
        Customer customer = new Customer();

        // Customer Registration
        customer.RegisterMe("+919999999999", PhoneType.APP ); // App or SMS?

        // Assuming Registration successful

        // Customer requests the token using a mobile app, or by sending SMS
        String CustomerToken =  customer.giveMeAToken("695000"); // Pin code

        if (CustomerToken != null) {
            //  Assuming Customer gets the token and he goes to the Outlet
        } else {
            // Seems there are no slots available. Try again later.
            return;
        }


        // At the Outlet, sales guy is scanning the token
        Boolean OutletVerification = new Outlet().isTheTokenShownByCustomerValid(CustomerToken);

        if (OutletVerification) {
            // Assuming the validation is success
            System.out.println("Customer says: Wow, I got the bottle!");
        } else {
            System.out.println("Sales guy says: Get lost!");
        }
    }

    public enum PhoneType { APP, SMS };

    private static class VQServer {
        // Database
        public String[] tokenDB = { "A", "B","C","D","E" };
        public String[] Outlets = {"Outlet1", "Outlet2", "Outlet3"};

        public void registerCustomer(String phoneNumber, PhoneType phonetype) {
            // Register customer

        }
        public String requestNewTokenByCustomer(String pinCode) {
            // Logic for - Token generation logic
            // Logic for - Find nearest outlet using pinCode

            // Send token by SMS if PhoneType is SMS

            return "C"; // Sample token
        }

        public Boolean validateTokenByOutlet(String token) {
            return Arrays.asList(tokenDB).contains(token); // Validate
        }
    };

    static VQServer vqServer = new VQServer();

    private static class Customer {

        public String giveMeAToken(String pinCode) {
            return vqServer.requestNewTokenByCustomer(pinCode);
        }
        public void RegisterMe(String phoneNumber, PhoneType phonetype) {
            // Customer Registration
            vqServer.registerCustomer(phoneNumber, phonetype);
        }
    }
    private static class Outlet {
        public Boolean isTheTokenShownByCustomerValid(String token) {
            return vqServer.validateTokenByOutlet(token);
        }
    }
}

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June 9, 2020

My Groovy HelloScript contribution to community

Here goes my contribution to HelloScript project by Praseed Pai.

GitHub: https://github.com/praseedpai/HelloScript_files/blob/master/Groovy/HelloScript.groovy

Source Code:


/**
 * HelloScript.groovy
 */

//  A Simple Console Output

    println "Hello World"

//  Some more
    print ("Hello World")
    System.out.println("K-Mug"); // Java style also works

// Declare variables
    def a = 100 // a number, def is about scope
    b = 100; // another number
    year = "Twenty Twenty" // a string

// String formatting & interpolation
    println "This is ${a}, ${b}, and " + year;

// Reassign a variable
    year = 2008; // dynamic typing

// if-else
    if (year > 2008)
        println "Welcome to the future - yes, we have flying cars!"
    else if (year < 2008)
        printLN "The past - please don't change anything. Don't step on any butterflies. And for the sake of all thats good and holy, stay away from your parents!"
    else
        println "Anything wrong with your time machine? You have not gone anywhere, kiddo."


// Range based for loop
for (i in 0..3) {
    println "$i Hi there!"
}

// Copying range value to a variable
    range_array = (0..10)
    print range_array;

// Array demo
    rules = ['Do no harm','Obey','Continue Living']
    println rules;

    rules << "Be Honest" // add one more item
    println rules

// Array demo, with mixed types
    more_rules = ['Do no harm','Obey','Continue Living', 404, 403, 500, 100f]
    println more_rules;

// Loop through Array
    i = 0
    while (i < rules.size()) {
        print "Rule " + (i + 1) + " : " + rules[i]
        i += 1
    }

    println() // just a newline

// Associating array
    associated = [
        'hello'    :    'world',
        'foo'    :    'bar',
        'lorem'    :    'ipsum'
    ]

    for (ele in associated) {
        print ele.key + " : " + ele.value
    }

    println() // just a newline

// Example of a Nested Loop
// To calculate Pythagorean Triplets
    n = 10
    println "-------------------------------------"
    for (va in (1..n)) {
        for (vb in (va..n)) {
            Integer c_square = va**2 + vb**2
            Integer vc = Math.sqrt(c_square)
            if ((c_square - vc**2) == 0) {
                println va + " " + vb + " " + vc
            }
        }
    }
    println "----------------------------------"

// Iterating over a list using range and size
    println "-------------------------------------"
    fibonacci = [0,1,1,2,3,5,8,13,21]
    for (i in (0..fibonacci.size()-1)) {
        println i + " " + fibonacci[i]
    }
    println "---------------------------------------"

// Parsing a line - split and join
    csv_values = "hello,world,how,are,you".split(",")
    println csv_values;
    println csv_values.join(":")

// A Single Argument Function
    def hello(name) {
        return "Hello ${name}!"
    }
    println hello("Praveen")

// A simple class
    class Movie {
        String name = ""
        Integer rating = 0

        def Movie(movieName) {
            this.name = movieName
            this.rateMovie()
        }

        def rateMovie() {
            this.rating = (this.name.length() % 10) + 1     // IMDBs rating algorithm. True story!
        }
        def printMovieDetails() {
            println "Movie : " +   this.name
            println "Rating : " + '*'.multiply(this.rating)  +  "(" + this.rating +")"
        }
    }

// Create the Object
    ncfom = new Movie("New Country for Old Men");     // It's a sequel!
    ncfom.printMovieDetails()

// Closures in action
    myList = ["Hello","My","World","What's","Up"]
    myList.each {
        print it + "-" // it is special
    }

// Multiplication table
    (1..10).each {
        println "${it} x 2 = ${it*2}"
    }

    println() // just a newline

// Tuples
    myTuple = new Tuple(1, 'two', 3, 'four')
    println myTuple

// File IO - Create a new file
    myFile = new File("myfile.txt");
    myFile.text = "Hello World! - from the file"
    myFile.createNewFile()

// File IO - Read from file
    println myFile.text

// File IO - With closure
    myFile.eachLine {
        l -> println l.toUpperCase()
    }

// Regular Expressions
    import java.util.regex.Pattern
    Pattern pattern = ~/World/
    str = "Hello World, this is Universe, not your World!"
    println "Found " + pattern.matcher(str).size() + " mathes."

View in GitHub | Made with wp-showgithubfile plugin [Code generated by wp-ShowGithubFile plugin]

June 7, 2020June 7, 2020

WordPress plugin – Show your source code directly from GitHub in your blog/website

Show a file, preferably source code file content in a WordPress blog post or page. This plugin shows always the latest code from GitHub.

Visit my GitHub repository to download the plugin for free – https://github.com/ninethsense/wp-ShowGithubFile

Source Code: (Live Example directly from GitHub 🙂


<?php
/**
 * Plugin Name: wp-ShowGithubFile
 * Description:       Show a file, preferably source code file content in a WordPress blog post or page
 * Version:           1.0.0
 * Author:            NinethSense
 * Author URI:        https://blog.ninethsense.com/
 * License:           GPL v2 or later
 */


    add_shortcode( "GitHub", "ShowGitHub" );
    function ShowGitHub($atts) {
        if (!isset($atts["file"]) && !strpos(strtolower($atts["file"]), "https://raw.githubusercontent.com/" )) {
            // Also, I want only files from GitHub. Modify this to show file from any URL
            return "[Invalid GitHub Raw file]";
        }
        
        $fh = @get_headers($atts["file"]);
        
        if (strpos($fh[0],"200") == 0) {
            return "[Invalid file]";
        }
        
        $fcontents = file_get_contents(trim($atts["file"]));
        $notphp = false;
        
        if (strpos($fcontents, "?php") == false) {
            $fcontents = "<?php ".$fcontents;
            $notphp = true;
        }
        
        // Make use of PHP syntax highlighing. Something is better than nothing.
        $fcontents = highlight_string($fcontents, TRUE);
        
        if ($notphp) {
            $fcontents = str_replace("&lt;?php&nbsp;", "",$fcontents);
            $notphp = false;
        }

        $fcontents = str_replace(["<code>", "</code>"], "",$fcontents);
        
        $fcontents = explode("<br />",$fcontents);
        
        $style = (isset($atts["style"])) ?$atts["style"]:"";
        $ret = "<div style='font-family:monospace;background-color:#dcd7ca;width:100%;overflow:auto;white-space:nowrap;border:solid 1px #aaa;font-size:10pt;$style'>";
        for ($i=0;$i<sizeof($fcontents);$i++) {
            $line = $fcontents[$i];
            $ret .= "<span style='font-size:10pt;display:block;width:40px;background-color:#aaa;float:left'>" . 
                str_pad($i+1, 3,'0',STR_PAD_LEFT) ." </span><span style='margin-left:10px;width:100%;inline-block'>" . $line . "</span><br />";
        }
        $ret .= "</div>";
       
        file_put_contents("D:\\test.txt", $ret);
        return $ret;

        
    }
?>

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June 6, 2020

PHP PortPing script – check host connectivity

Here is a script in PHP I wrote to check if a remote host and port are open for you to connect. Do not mistake this as an equivalent to ping command because ping uses ICMP and I used TCP using PHP’s famous fsockopen() function, and a small piece of AJAX.

You can get the latest source code from my GitHub code share page – https://github.com/ninethsense/code-share/

PHP:


function ping($host, $port) {
         $startTime = time();
         if ($fs = fsockopen($host, $port, $errCode, $errStr, 1)) {
             $timeTaken = (time()-$startTime)/1000;
         echo "Reply from $host:$port time={$timeTaken}ms";
             fclose($fs);
         } else {    
             echo "Request timed out.";
         }
         echo "<br>";
     }

JavaScript:


var count = 0;
             var intervalID = setInterval(function PortPing() {
                 var xhttp = new XMLHttpRequest();
                 xhttp.onreadystatechange = function() {
                     if (this.readyState == 4 && this.status == 200) {
                         document.getElementById("console").innerHTML += this.responseText;
                     }
                 };
                 xhttp.open("GET", "PortPing.php?source=self&host=<?=$host?>&port=<?=$port?>", true);
                 xhttp.send();
                 if (++count > <?=$t-1?>) {
                     clearInterval(intervalID);
                 }
             },2);

June 3, 2020

How to setup AWS SES / Simple Email Service

This is a tutorial on how to setup AWS SES / Simple Email Service.

Step 1 – Login to your AWS Console, then choose Services –> Customer Engagement –> Simple Email Service

Step 2 – Verify a New Domain

Choose “Domains” from left navigation panel, then click –> Verify a New Domain button

Step 2.2 – Enter Domain name

Also click checkbox Generate DKIM settings, though optional, I will be using this.

You will be displayed with a list of DNS settings in the next screen.

Once you completed the Step 3, click close.

Step 3 – Edit DNS records

You will have to login to your domain control panel and add these.

I will be using cPanel for this exercise. Steps are almost same with any domain/hosting control panel.

Step 4 – Wait for the domain to get verified. Click refresh icon on the right-top whenever you are impatient.

You have nothing to do here. Just wait for some 2-5-10 minutes.

Step 4.1 – Verify Email Address

You cannot even send a test mail, unless you have a email id verified.

Choose ‘Email Addresses’ from the left-navigation panel and click “Verify a New Email Address” button.

Make sure you enter an already existing email id.

A verification mail will be sent to your inbox.

There will be a URL you are expected to click, and you are verified.

Once verified, you should be able to see the verification status updated in AWS console too.

Step 5 – Send test mail.

Go back to Domains –> “Send a Test Mail” button.