velu liked web (programs, article, news, etc)

Few Useful Git Commands with Example for Beginners

2023-12-02T11:08:00.001+05:30

Git is a distributed version control system (DVCS) that is widely used for tracking changes in source code during software development. It was created by Linus Torvalds in 2005 to manage the development of the Linux kernel, but it has since become the de facto standard for version control in the software development industry.

Let’s dive into some Git commands,

git config

Usage: git config --global user.name “[name]”
Usage: git config --global user.email “[email address]”

This command sets the author name and email address respectively to be used with your commits.

git init

Usage: git init

This command is used to start a new repository in the current working directory.

git add

Usage: git add [file]

This command adds one or more files to the staging area.

Usage: git add * or git add .

This command adds one or more to the staging area.

git commit

Usage: git commit -m "[ Type in the commit message]"

This command records or snapshots the file permanently in the version history.

git status

Usage: git status

The git status command displays the current state of the local repository, including any changes that you’ve staged for a commit.

git branch

The git branch command is used to create and manage branches. Git branches are separate copies of your main codebase that you can change without disturbing the main code. Your main branch is the one you initialized using git init.

Usages:

list the all active branches.

git branch

creates a new branch.

git branch <branch_name>

delete the feature branch.

git branch -d [branch name]

Debounce in Javascript and React

2023-11-07T21:25:00.005+05:30

Debounce is a technique used to improve the performance of frequently executed actions, by delaying them, grouping them, and only executing the last call.

Imagine, Say for example, You need a search input that automatically queries results as you type.

You don't want to call the backend or API's with every keystroke, instead you only observe the final value. This is the perfect use for the debounce function, and in fact, it's the most common one.

Define basic debounce function with Javascript

Debounce is implemented using a timer, where the action executes only after the timeout. If the action is repeated before the timer has expires, we restart the timer.

function debounce(func, delay) {
let timer;
return function (...args) {
clearTimeout(timer);
timer = setTimeout(() => {
func.apply(this, args);
}, delay);
};
}

In the debounce function:

func is the original function you want to debounce.
delay is the time in milliseconds that you want to wait after the last call before invoking the original function.

Implement the debounce function

Create a function that accepts a function to debounce and the timeout delay as arguments.

const updateOptions = debounce(query => {
fetch(`https://dummyjson.com/products/search?q=${query}`)
.then(res => res.json())
.then(data => setOptions(data))
}, 1000)

input.addEventListener("input", e => {
updateOptions(e.target.value)
)}

Implement the debounce function with React

export default function SearchBox() {
  const [search, setSearch] = React.useState("");
  const [result, setResult] = React.useState([]);
  const handleChange = (e) => {
    setSearch(e.target.value);
  };

  let timeout;

  const handleSearch = async (query) => {
    setResult([]);
    if (query.length < 3) {
      return null;
    }
    const response = await fetch(
      `https://dummyjson.com/products/search?q=${query}`
    );
    const { products } = await response.json();
    setResult(products);
  };

  React.useEffect(() => {
    clearTimeout(timeout);
    timeout = setTimeout(() => {
      handleSearch(search);
    }, 500);
    return () => clearTimeout(timeout);
  }, [search]);

  return (
    <>
      <div className="mb-3 m-11">
        <div className="relative mb-4 flex w-full flex-wrap items-stretch">
          <form>
            <label
              htmlFor="default-search"
              className="mb-2 text-sm font-medium text-gray-900 
sr-only dark:text-white"
            >
              Search
            </label>
            <div className="relative">
              <div className="absolute inset-y-0 left-0 flex items-center 
pl-3 pointer-events-none">
                <svg
                  className="w-4 h-4 text-gray-500 dark:text-gray-400"
                  aria-hidden="true"
                  xmlns="http://www.w3.org/2000/svg"
                  fill="none"
                  viewBox="0 0 20 20"
                >
                  <path
                    stroke="currentColor"
                    strokeLinecap="round"
                    strokeLinejoin="round"
                    strokeWidth="2"
                    d="m19 19-4-4m0-7A7 7 0 1 1 1 8a7 7 0 0 1 14 0Z"
                  />
                </svg>
              </div>
              <input
                type="search"
                id="default-search"
                className="block w-full p-4 pl-10 text-sm text-gray-900
 border border-gray-300 rounded-lg bg-gray-50 focus:ring-blue-500 
focus:border-blue-500 dark:bg-gray-700 dark:border-gray-600 
dark:placeholder-gray-400 dark:text-white dark:focus:ring-blue-500 
dark:focus:border-blue-500"
                placeholder="Search Mockups, Logos..."
                value={search}
                onChange={handleChange}
              />
            </div>
          </form>
        </div>
      </div>

      <div className="mb-3 m-11">
        {result.map((item) => (
          <div className="text-xl">{item.title}</div>
        ))}
      </div>
    </>
  );
}

the useEffect runs every time the input value changes, after which there is a delay of 500 milliseconds, then the value result is updated with search value.

The Result will be

Happy Coding...😀

Captcha - PHP GD Library

2023-10-31T17:01:00.006+05:30

As Web Application development continues to grow, the need for CAPTCHA is essential. The captcha does it prevents a robot from trying to submit a form on your website.

Prerequisites:

A code Editor(Ex. VS Code)
Make sure GD(Graphics Draw) library is installed on your host.

What you need to know about Captcha

On the internet, there are scammers and hackers and they create risky apps to gain access to your app. You may have a lot of problems due to SQL injection, XSS attacks and spam mails.

Spam can increase server load and crash your online application, making it unavailable. Customers or site users are immediately affected. As a result it affects your internet business.

One of the best solutions to this problem is CAPTCHA. It protects against unauthorized access and spam bots. This stops bots from submitting meaningless information through the PHP contact form. Captcha uses a randomly generated code. Runtime production takes place. It appears in various forms.

Here are some examples of popular captcha types:

The user has to enter a random number that generates an audio, graphical (image) and text captcha code.
Validation ensures that a real human entered the value; In essence, a bot has difficulty filling in a captcha code.

Registration form with Captcha using PHP GD library

Let's say you have a basic user registration form where they can provide their name, gender and email.

We are going to implement CAPTCHA. CAPTCHA is mandatory field.Once the user submits the registration form we will validate the form and captcha.

HTML Contact Form with Captcha

Created a registration form using HTML, CSS and added two captcha fields. One field generates a Captcha image in the other field enter the value from captcha image to pass the validation.

Below is the code snippet for the index.php.

<!DOCTYPE html>
<html>

<head>
<meta name="viewport" content="width=device-width, initial-scale=1">
<style>
body {
font-family: Arial, Helvetica, sans-serif;
background-color: black;
}

* {
box-sizing: border-box;
}

.container {
max-width: 500px;
margin: 10px auto;
text-align: left;
font-family: sans-serif;
}

form {
border: 1px solid #1A33FF;
background: #ecf5fc;
padding: 5px;
}

input[type=text],
input[type=password] {
width: 100%;
padding: 15px;
margin: 5px 0 22px 0;
display: inline-block;
border: none;
background: #f1f1f1;
}

input[type=text]:focus,
input[type=password]:focus {
background-color: #ddd;
outline: none;
}

label {
font-weight: 600;
}

hr {
border: 1px solid #f1f1f1;
margin-bottom: 25px;
}

.registerbtn {
background-color: #04AA6D;
color: white;
padding: 16px 20px;
margin: 8px 0;
border: none;
cursor: pointer;
width: 100%;
opacity: 0.9;
}

.registerbtn:hover {
opacity: 1;
}

a {
color: dodgerblue;
}

.signin {
background-color: #f1f1f1;
text-align: center;
}

.form-center {
display: flex;
justify-content: center;
}

.captchaitem {
width: 100%;
display: flex;
flex-direction: row;
}
</style>
</head>

<body>
<div class="form-center">

<form action="/registration.php">
<div class="container">
<h1>Register</h1>
<p>Please fill in this form to create an account.</p>
<hr>

<label for="email"><b>Email</b></label>
<input type="text" placeholder="Enter Email" name="email" id="email" required>

<label for="email"><b>Phone</b></label>
<input type="text" placeholder="Enter Email" name="phone" id="phone" required>

<label for="psw"><b>Password</b></label>
<input type="password" placeholder="Enter Password" name="psw" id="psw" required>
<div class="captchaitem">
<div lass=" col-6">
<label for="email"><b>Captcha</b></label>
<input type="text" placeholder="Enter Captcha" name="captcha" id="captcha" required>
</div>
<div class=" col-6">
<label>Captcha Code</label>
<img src="captcha.php" alt="PHP Captcha">
</div>
</div>
<hr>
<p>By creating an account you agree to our <a href="#">Terms & Privacy</a>.</p>

<button type="submit" class="registerbtn">Register</button>
</div>

<div class="container signin">
<p>Already have an account? <a href="#">Sign in</a>.</p>
</div>
</form>
</div>
</body>

</html>

Creating The Captcha Page

Set the captcha code in the PHP session. Generate a random number with 6 characters.

This will be an output of the security code. Create a basic captcha using the GD library built-in functions. This code will generate the captcha image.

Create captcha.php file and insert the given code in the file.

<?php

session_start();
// Generate captcha code
$randomNum = md5(random_bytes(64));
$captchaCode = substr($randomNum, 0, 6);
// Assign captcha in session
$_SESSION['CAPTCHA_CODE'] = $captchaCode;
// Create captcha image
$layer = imagecreatetruecolor(168, 37);
$captchaBg = imagecolorallocate($layer, 207, 104, 71);
imagefill($layer, 0, 0, $captchaBg);
$captchaTextColor = imagecolorallocate($layer, 0, 0, 0);
imagestring($layer, 5, 55, 10, $captchaCode, $captchaTextColor);
header("Content-type: image/jpeg");
imagepng($layer);
imagedestroy($layer);

?>

After running the above snippet, the Interface below is what you will see on the index.php page on your browser.

Captcha validation for the Registration Form

When the user entered the wrong captcha user will also be alerted with a message. Create register.php file and insert the given code in the file.

<?php
session_start();
$captchaError = [];
if ($_POST) {
list('captcha' => $captcha, 'email' => $email, 'password' => $password) = $_POST;

$captchaInput = filter_var($_POST["captcha"], FILTER_DEFAULT);
if (empty($captcha)) {
$captchaError = array(
"status" => "alert-danger",
"message" => "Please enter the captcha."
);
} else if ($_SESSION['CAPTCHA_CODE'] == $captchaInput) {
$captchaError = array(
"status" => "alert-success",
"message" => "Your form has been submitted successfuly."
);
} else {
$captchaError = array(
"status" => "alert-danger",
"message" => "Captcha is invalid."
);
}
}

Include the register.php in the index.php file to bind the captcha with registeration form.

<?php include('register.php'); ?>

<!DOCTYPE html>
<html>

<head>
<meta name="viewport" content="width=device-width, initial-scale=1">
<style>
body {
font-family: Arial, Helvetica, sans-serif;
background-color: black;
}

* {
box-sizing: border-box;
}

.container {
max-width: 500px;
margin: 10px auto;
text-align: left;
font-family: sans-serif;
}

form {
border: 1px solid #1A33FF;
background: #ecf5fc;
padding: 5px;
}

input[type=text],
input[type=password] {
width: 100%;
padding: 15px;
margin: 5px 0 22px 0;
display: inline-block;
border: none;
background: #f1f1f1;
}

input[type=text]:focus,
input[type=password]:focus {
background-color: #ddd;
outline: none;
}

label {
font-weight: 600;
}

hr {
border: 1px solid #f1f1f1;
margin-bottom: 25px;
}

.registerbtn {
background-color: #04AA6D;
color: white;
padding: 16px 20px;
margin: 8px 0;
border: none;
cursor: pointer;
width: 100%;
opacity: 0.9;
}

.registerbtn:hover {
opacity: 1;
}

a {
color: dodgerblue;
}

.signin {
background-color: #f1f1f1;
text-align: center;
}

.form-center {
display: flex;
justify-content: center;
}

.captchaitem {
width: 100%;
display: flex;
flex-direction: row;
}

.captcha-valid {
width: 100%;
display: flex;
}

.alert-success {
background-color: green;
color: #000;
width: 100%;
padding: 5px;
margin: 0 0 10 auto;
}

.alert-danger {
background-color: red;
color: #fff;
width: 100%;
padding: 5px;
margin: 0 0 10 auto;
}
</style>
</head>

<body>
<div class="form-center">

<form method="post">
<div class="container">
<h1>Register</h1>
<p>Please fill in this form to create an account.</p>
<hr>

<?php if (!empty($captchaError)) { ?>
<div class="captcha-valid">
<div class="alert text-center <?php echo $captchaError['status']; ?>">
<?php echo $captchaError['message']; ?>
</div>
</div>
<?php } ?>
<label for="email"><b>Email</b></label>
<input type="text" placeholder="Enter Email" name="email" id="email" required>

<label for="email"><b>Phone</b></label>
<input type="text" placeholder="Enter Phone" name="phone" id="phone" required>

<label for="psw"><b>Password</b></label>
<input type="password" placeholder="Enter Password" name="psw" id="psw" required>
<div class="captchaitem">
<div lass=" col-6">
<label for="email"><b>Captcha</b></label>
<input type="text" placeholder="Enter Captcha" name="captcha" id="captcha" required>
</div>
<div class=" col-6">
<label>Captcha Code</label>
<img src="captcha.php" alt="PHP Captcha">
</div>
</div>
<hr>
<p>By creating an account you agree to our <a href="#">Terms & Privacy</a>.</p>

<button type="submit" name="submit" class="registerbtn">Register</button>
</div>

<div class="container signin">
<p>Already have an account? <a href="#">Sign in</a>.</p>
</div>
</form>
</div>
</body>

</html>

Now fill in the fields of the registration form and submit it, it will show success in a green background. But if it’s not successful it will show error message in a red background.

Conclusion

we successfully created a simple Captcha in PHP and implemented it with the PHP registration form.

Increasing Website Page Load Speeds

2014-04-29T12:02:00.000+05:30

By increasing your website speed, you can: increase user experience, have higher conversions, promote engagement, and generate even higher search rankings.

Things to consider

1) Eliminate render-blocking JavaScript and CSS in above-the-fold content
2) Optimize images
3) Leverage browser caching
4) Reduce server response time
5) Minify CSS
6) Minify HTML
7) Minify JavaScript

Eliminate render-blocking JavaScript and CSS in above-the-fold content

This means that your HTML references a blocking external JavaScript file in the above-the-fold portion of your page.
JavaScript needed to render the above-the-fold region should be inlined, and JavaScript needed to add additional functionality to the page should be deferred until after the above-the-fold content has been delivered.

Generally, the bulk of the JavaScript code handles user-initiated events occur after the page is loaded.
In order to defer loading of these JavaScripts insert a JavaScript event listener in the head of the containing document that forces the external file to be loaded after the onload event.

I recommend adding a very simple scripted DOM element. Here’s an example code that Google recommends.

// Add a script element as a child of the body

function downloadJSAtOnload() {

var element = document.createElement("script");

element.src = "deferredfunctions.js";

document.body.appendChild(element);

}

// Check for browser support of event handling capability

if (window.addEventListener)

window.addEventListener("load", downloadJSAtOnload, false);

else if (window.attachEvent)

window.attachEvent("onload", downloadJSAtOnload);

else window.onload = downloadJSAtOnload;

</script>

If you are using a JavaScript library (like jQuery) it can be safely added after the above-the-fold content is rendered.

Optimize images

Keep your image sizes to a minimum to reduce the amount of time a person waits for it to load. Formatting and compressing images can save many bytes of data. You can use Compress Now, an online image compressor.

Leverage browser caching

Use .htaccess to cache files.

ExpiresActive On

ExpiresByType image/jpg "access plus 1 year"

ExpiresByType image/jpeg "access plus 1 year"

ExpiresByType image/gif "access plus 1 year"

ExpiresByType image/png "access plus 1 year"

ExpiresByType text/css "access plus 1 month"

ExpiresByType application/pdf "access plus 1 month"

ExpiresByType text/x-javascript "access plus 1 month"

ExpiresByType application/x-shockwave-flash "access plus 1 month"

ExpiresByType image/x-icon "access plus 1 year"

ExpiresDefault "access plus 2 days"

</IfModule>

Reduce server response time

Load your CSS first and your JavaScript last.

<!DOCTYPE html>

<html>

<head>

<title>RRpowered.com</title>

/*CSS goes here*/

</style>

/*JavaScript*/

</script>

</head>

<body>

Body content here

</body>

</html>

Use Gzip to compress files

How to enable Gzip on your server:

mod_gzip_on Yes

mod_gzip_dechunk Yes

mod_gzip_item_include file .(html?|txt|css|js|php|pl)$

mod_gzip_item_include handler ^cgi-script$

mod_gzip_item_include mime ^text/.*

mod_gzip_item_include mime ^application/x-javascript.*

mod_gzip_item_exclude mime ^image/.*

mod_gzip_item_exclude rspheader ^Content-Encoding:.*gzip.*

</ifModule>

Make Fewer HTTP Requests and avoid CSS Expressions.

Minify CSS, HTML, JavaScript

For minifying HTML, you can use an online compressor called HTML Compressor
For minifying CSS and JavaScript, use YUI Compressor

A good tool for analyzing your website speed is Google’s PageSpeed Insights tool!

Source From: http://www.rrpowered.com

PHP Time Ago

2014-03-03T17:27:00.002+05:30

A simple way to display ago with UNIX time.

Displaying the time ago.
To display the time ago. Just add this where you want to display the time ago.

<?PHP
/*Created by Barrett at RRPowered.com*/
include_once('ago.php');//Include the ago.php file 
$cur_time1 ="1291684422";//Your Unix time from database
echo time_ago($cur_time1) ;
?>

Here is the PHP file!
This file is called ago.php

<?PHP
/*Created by Barrett at RRPowered.com*/
//Call the function
function time_ago($cur_time){
$time_ = time() - $cur_time;
 
$seconds =$time_;
$minutes = round($time_ / 60);
$hours = round($time_ / 3600);
$days = round($time_ / 86400);
$weeks = round($time_ / 604800);
$months = round($time_ / 2419200);
$years = round($time_ / 29030400);
 
//Seconds
if($seconds <= 60){ 
   $time="$seconds seconds ago";   
 
//Minutes    
}else if($minutes <= 60){ 
   if($minutes == 1){
   $time="one minute ago";
   }else{
   $time="$minutes minutes ago";
   } 
//Hours
}else if($hours <= 24){ 
  if($hours == 1){
  $time="one hour ago";
  }else{
  $time="$hours hours ago";
  } 
//Days 
}else if($days <= 7){ 
   if($days == 1){
   $time="one day ago";
   }else{
   $time="$days days ago";
   } 
//Weeks
}else if($weeks <= 4){ 
  if($weeks == 1){
  $time="one week ago";
  }else{
  $time="$weeks weeks ago";
  } 
//Months  
}else if($months <= 12){ 
  if($months == 1){
  $time="one month ago";
  }else{
  $time="$months months ago";
  } 
//Years 
}else{ 
  if($year == 1){
  $time="one year ago";
  }else{
  $time="$year years ago";
  }  
}
return $time;
}
?>


Source Form: http://www.rrpowered.com

How to use local storage for JavaScript

2014-02-17T18:10:00.001+05:30

Creating an to-do app is usually the first application you learn how to build in JavaScript but the problem with all those apps is that when you reload the page all those to-do’s are gone. There is a simple solution though, and that’s to use local storage.

The good thing about local storage is that you can save those bits of data to the user’s computer so that when they reload the page all of their todo’s will still be there and local storage is actually quite simple when it comes to saving the data and making it available on the page.

What is local storage?

Local storage is a part of web storage, which itself is part of the HTML5 specification. There are two options for storing data in the specification:

Local Storage: stores data with no expiration date and this is the one we will be using because we want our to-do’s to stay on the page for as long as possible.
Session Storage: only saves the data for one session so if the user closes the tab and reopens it all their data will be gone.

In simple terms, all that web storage does is store named key/value pairs locally and unlike cookies this data persists even if you close your browser or turn off your computer.

The HTML

If we think about a to-do list what we will need is :

An input to place our to-do.
An input button to add our to-do.
A button to clear all the to-do’s.
A placeholder unordered list where our to-do’s will be placed in list items.
And finally we need a placeholder div to show an alert when you try to enter an empty to do.

So our HTML should look something like this:

<section>
<form id="form" action="#" method="POST">
<input id="description" name="description" type="text" />
<input id="add" type="submit" value="Add" />
<button id="clear">Clear All</button>
</form>
<div id="alert"></div>
<ul id="todos"></ul></section>

It’s a pretty standard placeholder HTML and with our javascript we can fill all this up with dynamic content. Since we will be using jQuery in this example you should also include it in your HTML document.

The JavaScript

If we think about the structure of a simple to-do app the first thing we need to do is check for when the user clicks on add button and check if the input has an empty value, like so:

$('#add').click( function() {
   var Description = $('#description').val();
   //if the to-do is empty
   if($("#description").val() == '') {
    $('#alert').html
("<strong>Warning!</strong> You left the to-do empty");
    $('#alert').fadeIn().delay(1000).fadeOut();
    return false;
   }

All we did was check for a click on the add button and run a simple test to check if the user filled the input with something. If not, the alert div fades in and stays for 1000ms and then fades out. Finally we return false so that the browser doesn’t read the rest of the script and still add the list item.

The next thing we need to do is insert a list item with the value in the input and we will prepend this so that when the user adds a to-do it will always go to the beginning of the list and then save that list item to local storage, like so:

// add the list item
   $('#todos').prepend("<li>" + Description + "</li>");
   // delete whatever is in the input
   $('#form')[0].reset();
   var todos = $('#todos').html();
   localStorage.setItem('todos', todos);
   return false;
});

As you can see it’s pretty standard jQuery and when it comes to local storage we need to save a key and a value. The key is a name we set for ourselves and in this case i just called it ‘todos’ and then we need to specify what we actually want to save, and in this case that is all the HTML that is placed inside the todos unordered list. As you can see we just grabbed that using jQuery and we finally returned false so that the form doesn’t submit and our page doesn’t reload.

Our next step is to check if we have something on local storage already saved in our machine and if we do we need to place that in the page, so since we gave our key the name todos we need to check for its existence like so:

// if we have something on local storage place that
if(localStorage.getItem('todos')) {
$('#todos').html(localStorage.getItem('todos'));
}

We used a simple if statement to check and then we merely got what we have on local storage and place that as the HTML of the to-do’s unordered list.

If you test our simple app and we reload the page we see that it’s already working and all we have left is to create the function for when the user chooses to clear all the to-do’s; when that happens we will clear all local storage, reload the page for our changes take effect, and then return false to prevent the hash in front of the url like so:

// clear all the local storage
$('#clear').click( function() {
window.localStorage.clear();
location.reload();
return false;
});

With this done we have our app fully working. The full code looks like this:

$('#add').click( function() {
   var Description = $('#description').val();
  if($("#description").val() == '') {
    $('#alert').html
("<strong>Warning!</strong> You left the to-do empty");
    $('#alert').fadeIn().delay(1000).fadeOut();
    return false;
   }
   $('#todos').
prepend("<li><input id='check' name='check' type='checkbox'/>" 
+ Description + "</li>");
   $('#form')[0].reset();
   var todos = $('#todos').html();
   localStorage.setItem('todos', todos);
   return false;
});
if(localStorage.getItem('todos')) {
$('#todos').html(localStorage.getItem('todos'));
}
$('#clear').click( function() {
window.localStorage.clear();
location.reload();
return false;
});

Store an Array in localStorage
`localStorage` only supports strings. Use `JSON.stringify()` and `JSON.parse()`. for store and retrieve the array.

var names = [];
names[0] = prompt("New member name?");
localStorage["names"] = JSON.stringify(names);
//...
var storedNames = JSON.parse(localStorage["names"]);

Browser support

The support for web storage is pretty good for an HTML5 specification; it is supported by all the major browsers and even IE8, so the only thing you might need to be wary of is IE7 if you’re still supporting that.

Conclusion

Local storage in small apps like this can very welcome substitutes for databases. Storing small amounts of data doesn’t need to be complex.

Source From: http://www.webdesignerdepot.com

PHP MySQL – Get Next Auto Increment Value of a Table

2014-01-21T18:57:00.001+05:30

We do not often need this but sometimes when we need to retrieve the next auto increment value of a table (without incrementing the auto increment value of course), this solution below will help.

<?php
 
$query = mysql_query("SHOW TABLE STATUS WHERE 
name='your_table_name_here'");

if (mysql_num_rows($query)) {
 $result = mysql_fetch_assoc($query);
 echo $result['Auto_increment'];
} else {//error
 //error control here
}
 
?>

Just replace “your_table_name_here” with your mySQL table name.

As a Function

Furthermore, making it a PHP function would make the solution looks clean.

<?php
 
function get_next_value($tablename) {
 $query = mysql_query("SHOW TABLE STATUS 
WHERE name='".mysql_real_escape_string($tablename)."'");

 if (mysql_num_rows($query)) {
  $result = mysql_fetch_assoc($query);
  return $result['Auto_increment'];
 } else {//error
  return false;
 }
}
 
//usage
$nextval = get_next_value('your_table_name_here');
 
?>

Hope this helps.

Source From: http://zenverse.net/php-mysql-next-auto-increment-value

Robot.txt

2013-12-20T11:44:00.001+05:30

Robot.txt is a text file which is used to instruct the search engines for how to crawl and index the pages on your site. The search engines should be obey the robot.txt. The search engine follow the instruction specified by robot.txt file. If you want to some of your pages are not crawl by search engine, then you can protect that pages in robot.txt. Then the search engine don't crawl particular pages specified by your robot.txt file.

The search engine comes to your robot.txt file before it crawl to your pages. It must be placed in your main directory. Otherwise, it can not able to find robot.txt file in your server.

Syntax:
User-agent: *
Allow: /
where,
User-agent represents the search engines.
Allow means the robot.txt file allow the all search engines to crawl all of your contents.

Disallow the all crawlers by robot.txt:
User-agent: *
Disallow: /
Now, the search engine don't crawl and index your pages.

Disallow the particular folder by robot.txt:
User-agent: *
Disallow: /sample/example.php
Now, the search engine don't index example.php file in sample folder.

Robots meta tags by robot.txt:
It control the individual pages present in search result. It should be present within head tag.
For example,
<meta name="robots" content="noindex">
The above line instructs the search engine to don't show this page in search result.

Disallow the particular search engine by robot.txt:
If you want to restrict particular search engines don't index your pages, then you can use robot.txt to restrict it.

Syntax:
User-agent: Googlebot
Disallow: /
Now all the search engines index your pages except google. Googlebot is the search engine of google.

Source: http://www.phponwebsites.com/2013/12/robottxt.html

Useful snippets for php developers

2013-12-16T12:41:00.001+05:30

Extract keywords from a webpage

The title said it all: A great code snippet to easily extract meta keywords from any webpage.

<?php

$meta = get_meta_tags('http://www.emoticode.net/');
$keywords = $meta['keywords'];
// Split keywords
$keywords = explode(',', $keywords );
// Trim them
$keywords = array_map( 'trim', $keywords );
// Remove empty values
$keywords = array_filter( $keywords );

print_r( $keywords );

?>

Find All Links on a Page

Using the DOM, you can easily grab all links from any webpage. Here’s a working example:

<?php

$html = file_get_contents('http://www.example.com');

$dom = new DOMDocument();
@$dom->loadHTML($html);

// grab all the on the page
$xpath = new DOMXPath($dom);
$hrefs = $xpath->evaluate("/html/body//a");

for ($i = 0; $i < $hrefs->length; $i++) {
       $href = $hrefs->item($i);
       $url = $href->getAttribute('href');
       echo $url.'<br />';
}

?>

Create Data URI’s

Data URI’s can be useful for embedding images into HTML/CSS/JS to save on HTTP requests. The following function will create a Data URI based on $file for easier embedding.

function data_uri($file, $mime) {
  $contents=file_get_contents($file);
  $base64=base64_encode($contents);
  echo "data:$mime;base64,$base64";
}

Download & save a remote image on your server

Downloading an image on a remote server and saving it on your own server is useful when building websites, and it’s also very easy to do. The two lines of code below will do it for you.

$image = file_get_contents('http://www.url.com/image.jpg');
file_put_contents('/images/image.jpg', $image); //Where to save the image

Detect browser language

If your website is multilingual, it can be useful to detect the browser language to use this language as the default. The code below will return the language used by the client’s browser.

function get_client_language($availableLanguages, $default='en'){
 if (isset($_SERVER['HTTP_ACCEPT_LANGUAGE'])) {
  $langs=explode(',',$_SERVER['HTTP_ACCEPT_LANGUAGE']);

  foreach ($langs as $value){
   $choice=substr($value,0,2);
   if(in_array($choice, $availableLanguages)){
    return $choice;
   }
  }
 } 
 return $default;
}

Display number of Facebook fans in full text

If you have a Facebook page for your website or blog, you might want to display how many fans you have. This snippet will help you to get your Facebook fan count, in full text. Don’t forget to add your page ID on line 2.

<?php
 $page_id = "YOUR PAGE-ID";
 $xml = @simplexml_load_file(

"http://api.facebook.com/restserver.php?method=facebook.fql.query&

query=SELECT%20fan_count%20FROM%20page%20WHERE%20page_id=".$page_id."")

or die ("a lot");

 $fans = $xml->page->fan_count;
 echo $fans;
?>

Source From: http://www.catswhocode.com

How to send email from the Linux command line

2013-11-18T13:42:00.004+05:30

First run a quick test to make sure the “sendmail” application is installed and working correctly. Execute the following command, replacing “you@youremailid.com” with your e-mail address.
# mail -s “Hello world” you@youremailid.com
Hit the return key and you will come to a new line. Enter the text “This is a test from my server”. Follow up the text by hitting the return key again. Then hit the key combination of Control+D to continue. The command prompt will ask you if you want to mark a copy of the mail to any other address, hit Control+D again. Check your mailbox. This command will send out a mail to the email id mentioned with the subject, “Hello world”.
To add content to the body of the mail while running the command you can use the following options. If you want to add text on your own:
# echo “This will go into the body of the mail.” | mail -s “Hello world” you@youremailid.com
And if you want mail to read the content from a file:
# mail -s “Hello world” you@youremailid.com < /home/calvin/application.log
Some other useful options in the mail command are:
-s subject (The subject of the mail)
-c email-address (Mark a copy to this “email-address”, or CC)
-b email-address (Mark a blind carbon copy to this “email-address”, or BCC)
Here’s how you might use these options:
# echo “Welcome to the world of Calvin n Hobbes” | mail -s “Hello world” calvin@cnh.com -c hobbes@cnh.com -b susie.derkins@cnh.com

MUTT

One of major drawbacks of using the mail command is that it does not support the sending of attachments. mutt, on the other hand, does support it. I’ve found this feature particularly useful for scripts that generate non-textual reports or backups which are relatively small in size which I’d like to backup elsewhere. Of course, mutt allows you to do a lot more than just send attachments. It is a much more complete command line mail client than the “mail” command. Right now we’ll just explore the basic stuff we might need often. Here’s how you would attach a file to a mail:
# echo “Sending an attachment.” | mutt -a backup.zip -s “attachment” calvin@cnh.com
This command will send a mail to calvin@cnh.com with the subject (-s) “attachment”, the body text “Sending an attachment.”, containing the attachment (-a) backup.zip. Like with the mail command you can use the “-c” option to mark a copy to another mail id.

Read more at http://www.simplehelp.net/2008/12/01/how-to-send-email-from-the-linux-command-line/#ZW60emwX4KkihuKF.99

MAIL

First run a quick test to make sure the “sendmail” application is installed and working correctly. Execute the following command, replacing “you@youremailid.com” with your e-mail address.

# mail -s “Hello world” you@youremailid.com

Hit the return key and you will come to a new line. Enter the text “This is a test from my server”. Follow up the text by hitting the return key again. Then hit the key combination of Control+D to continue. The command prompt will ask you if you want to mark a copy of the mail to any other address, hit Control+D again. Check your mailbox. This command will send out a mail to the email id mentioned with the subject, “Hello world”.

To add content to the body of the mail while running the command you can use the following options. If you want to add text on your own:

# echo “This will go into the body of the mail.” | mail -s “Hello world” you@youremailid.com

And if you want mail to read the content from a file:

# mail -s “Hello world” you@youremailid.com < /home/calvin/application.log

Some other useful options in the mail command are:

-s subject (The subject of the mail)
-c email-address (Mark a copy to this “email-address”, or CC)
-b email-address (Mark a blind carbon copy to this “email-address”, or BCC)

Here’s how you might use these options:

# echo “Welcome to the world of Calvin n Hobbes” | mail -s “Hello world” calvin@cnh.com -c hobbes@cnh.com -b susie.derkins@cnh.com

MUTT

One of major drawbacks of using the mail command is that it does not support the sending of attachments. mutt, on the other hand, does support it. I’ve found this feature particularly useful for scripts that generate non-textual reports or backups which are relatively small in size which I’d like to backup elsewhere. Of course, mutt allows you to do a lot more than just send attachments. It is a much more complete command line mail client than the “mail” command. Right now we’ll just explore the basic stuff we might need often. Here’s how you would attach a file to a mail:

# echo “Sending an attachment.” | mutt -a backup.zip -s “attachment” calvin@cnh.com

This command will send a mail to calvin@cnh.com with the subject (-s) “attachment”, the body text “Sending an attachment.”, containing the attachment (-a) backup.zip. Like with the mail command you can use the “-c” option to mark a copy to another mail id.

Source From: http://www.simplehelp.net/2008/12/01/how-to-send-email-from-the-linux-command-line/

adfasdasdMAIL

MUTT

Some useful tools for web developers

2013-07-18T12:49:00.000+05:30

1. HTML and CSS Table Border Style Wizard
http://www.somacon.com/p141.php

2. oAuth End Points Cheat Sheet
http://www.cheatography.com/kayalshri/cheat-sheets/oauth-end-points/

3. HTML Compression Tool
http://www.textfixer.com/html/compress-html-compression.php

4. CSS Compression Tool
http://www.codebeautifier.com/#skip

5. Online Code Beautifier for JavaScript, HTML, CSS and PHP
http://ctrlq.org/beautifier/

6. Online JavaScript beautifier
http://jsbeautifier.org/

7. CSS Drive Gallery- CSS Compressor
http://www.cssdrive.com/index.php/main/csscompressor/

8. 10 useful .htaccess snippets to have in your toolbox | CatsWhoCode.com
http://www.catswhocode.com/blog/10-useful-htaccess-snippets-to-have-in-your-toolbox

9. Google URL Shortener
http://goo.gl/

10. Google oAuth2.0 Playground
https://developers.google.com/oauthplayground/

11. oAuth End Points Cheat Sheet
http://www.cheatography.com/kayalshri/cheat-sheets/oauth-end-points/

Autocomplete Textbox with JQuery

2012-10-10T12:14:00.000+05:30

Very useful stuff of autocomplete textbox with jquery.

<html>
    <head>
    <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>    
    <link rel="stylesheet" href="http://code.jquery.com/ui/1.9.0/themes/base/jquery-ui.css" />    
    <script src="http://code.jquery.com/ui/1.9.0/jquery-ui.js"></script>
    <script type='text/javascript'>//<![CDATA[ 
    $(window).load(function(){
    $("#myfriend").autocomplete({
        source: [
            "Mysql",
            "Asp",
            "BASIC",
            "C",            
            "PHP"
        ],
        minLength: 2,
        select: function(event, ui) {
            event.preventDefault();
            $("#myfriend").val(ui.item.label);
            $("#selected-myfriend").val(ui.item.label);
        },
        focus: function(event, ui) {
            event.preventDefault();
            $("#myfriend").val(ui.item.label);
        }
    });
    });//]]>  
    </script>
    </head>
    <body>
        <input type="text" id="myfriend" />
    </body>
</html>

It comes with the search stuff, based on the user entered the input length.

minLength: 2,

The autocomplete will come after the user given the string length is 2. The autocomplete need to integrate with database stuff also cover here, Just remove the source container "[....]" and add the server side script file for query the database.

<html>
    <head>
    <script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1/jquery.min.js"></script>    
    <link rel="stylesheet" href="http://code.jquery.com/ui/1.9.0/themes/base/jquery-ui.css" />    
    <script src="http://code.jquery.com/ui/1.9.0/jquery-ui.js"></script>
    <script type='text/javascript'>//<![CDATA[ 
    $(window).load(function(){
    $("#myfriend").autocomplete({
        source: "autosearch.php",
        minLength: 2,
        select: function(event, ui) {
            event.preventDefault();
            $("#myfriend").val(ui.item.label);
            $("#selected-myfriend").val(ui.item.label);
        },
        focus: function(event, ui) {
            event.preventDefault();
            $("#myfriend").val(ui.item.label);
        }
    });
    });//]]>  
    </script>
    </head>
    <body>
        Country: <input type="text" id="myfriend" />
    </body>
</html>

Here the source data get from the autosearch.php file with the GET method. The output of the source file sould be the json data.

//autosearch.php 

<?php 

$term = $_GET['term'];

$link = mysql_connect('localhost', 'user', 'password');
$db_selected = mysql_select_db('database', $link);

$sql = "SELECT name FROM country WHERE name LIKE '%{$term}%' LIMIT 5";

$rs = mysql_query($sql);

$autoArray = array();

While($row=mysql_fetch_row($rs)){

   $autoArray[] = $row[0];

}

echo json_encode($autoArray);

?>

Thats it.

Add Proxy Context Stream For PHP

2012-09-25T18:54:00.006+05:30

Using Curl:

<?php
    $proxyauth = 'username:pwd';
    $ch = curl_init();
    curl_setopt ($ch, CURLOPT_URL, $url);
    curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt ($ch, CURLOPT_PROXY, '10.0.0.125:8080');
    curl_setopt ($ch, CURLOPT_PROXYUSERPWD, $proxyauth);
    $content = curl_exec($ch);
    curl_close($ch);
?>

No Credential require your proxy, remove the following line

curl_setopt ($ch, CURLOPT_PROXYUSERPWD, $proxyauth);

Using Context Stream:

<?php
$url = 'http://www.google.com';
$proxy = 'tcp://10.0.0.100:8080';
$auth = base64_encode('username:pwd');
$context = array(
'http' => array(
        'proxy' => $proxy,
        'header' => "Proxy-Authorization: Basic $auth",
        'request_fulluri' => True,
        ),
);
$context = stream_context_create($context);
echo $body = file_get_contents($url, False, $context);
?>

No Credential require your proxy, remove the following line

'header' => "Proxy-Authorization: Basic $auth",

Thats it

PHP Script show all errors

2012-09-25T18:06:00.001+05:30

Sometime the PHP script doesn't show error.  It seems the server default

config set not to show the errors. Here's how to override it.

error_reporting(E_ALL);
ini_set('display_errors', '1');

Copy and paste it on your page begin after the php tag start.

Backup and Restore MySQL Database Using mysqldump

2012-08-13T12:36:00.003+05:30

--> mysqldump is an effective tool to backup MySQL database. It creates a *.sql file with DROP table, CREATE table, Lock table and INSERT into sql-statements of the source database. To restore the database, execute the *.sql file on destination database.

Using mysqldump, you can backup a local database and restore it on a remote database at the same time, using a single command. In this article, let us review several practical examples on how to use mysqldump to backup and restore.

For the impatient, here is the quick snippet of how backup and restore MySQL database using mysqldump:

backup: # mysqldump -u root -p[root_password] [database_name] > dumpfilename.sql

restore:# mysql -u root -p[root_password] [database_name] < dumpfilename.sql

How To Backup MySQL database

1. Backup a single database:

This example takes a backup of sugarcrm database and dumps the output to abc.sql

# mysqldump -u root -p abc > abc.sql

# mysqldump -u root -p[root_password] [database_name] > dumpfilename.sql

2. Backup multiple databases:

# mysqldump -u root -p --databases database1 database2 > database1_database2.sql

3. Backup all the databases:

# mysqldump -u root -p --all-databases > /tmp/all-database.sql

4. Backup a specific table:

# mysqldump -u root -p abcdatabase usertable > /tmp/abc_user_table.sql

# mysqldump -u root -p test t1 --where="1=1 limit 100" > arquivo.sql

How To Restore MySQL database

1. Restore a database

# mysql -u root -p databasename < /tmp/all-database.sql

# mysql -u root -p[root_password] [database_name] < dumpfilename.sql

2. Backup a local database and restore to remote server using single command:

This is a sleek option, if you want to keep a read-only database on the remote-server, which is a copy of the master database on local-server. The example below will backup the sugarcrm database on the local-server and restore it as sugarcrm1 database on the remote-server. Please note that you should first create the sugarcrm1 database on the remote-server before executing the following command.

[local-server]# mysqldump -u root -p abc | mysql \ -u root -p --host=remote-server -C abc1 [Note: There are two -- (hyphen) in front of host]

Source From: http://www.thegeekstuff.com/2008/09/backup-and-restore-mysql-database-using-mysqldump/

phpMyAdmin - To change the authentication timeout value and increase the default number of result in browse mode.

2012-07-02T11:27:00.000+05:30

Sometime you might get crazy for the authentication timeout while working with phpMyAdmin. By default the timeout value is set to 1800 seconds which is 30 minutes.

You can easily increase this time limit value by editing your config file for phpMyAdmin. Simply open the config file (config.inc.php) and add or update the following config variable with increase/decrease value.

$cfg['LoginCookieValidity'] = 36000; // In seconds

Another thing, I hate to browse the records of a table by clicking next -> next -> and next. So, I changed the default listing from 30 to 100. Add following config variable and your preferred number of records in browse mode.

$cfg['MaxRows'] = 100;

That's all. Hope this helps.

How to Install and Run Internet Explorer 7/8 On Ubuntu 11.04/11.10

2012-05-02T17:08:00.002+05:30

This will be possible with the help of Wine and winetricks. To install Wine 1.3 on Ubuntu 11.10/11.04, check this article (winetricks will be installed automatically with Wine 1.3). Then open the terminal and run one of these commands to install IE 7/8:

Internet Explorer 7

To download IE7, use this command:

winetricks ie7

Then run IE7 with this command:

wine 'C:\Program Files\Internet Explorer\iexplore'

Internet Explorer 8

Run this command to download IE8:

winetricks ie8

To start IE8, run this command:

wine 'C:\Program Files\Internet Explorer\iexplore'

Note: You may encounter bugs while testing IE 7/8 using Wine.

Source From: http://www.upubuntu.com/2011/10/how-to-install-and-run-internet.html

6 Tips For Designing an SEO Friendly Website

2012-02-28T11:22:00.002+05:30

It’s not enough these days to design a beautiful, functional website that addresses your clients needs. If you truly want your client to reap the benefits of having an online presence, then SEO is a necessity. Search Engine Optimization is a method of improving the visibility of a website in search engines through organic search results, and is now a viable online marketing tool for a lot of businesses.

Through the following design practices you can improve a website’s SEO and ultimately their visibility. With these foundations in place, you’ll have the peace of mind of knowing the website you spent hours designing (and developing) is now a top contender for search engine visibility. You may also find some of these tactics also go far in improving user experience as well.

Keywords

Keywords are an important part of any search engine optimization campaign. If you’re using the wrong keywords, search engines and your target market may never find you. It’s important when starting a website to first establish what the business objectives are. Do you want to target a local area, national or global? With this plan in place you can then build pages that target these specific keywords, or decide where these pages may go down the line once the foundation is built.

The process of creating
1. Create a list of potential keywords (i.e. words that are relevant but not overly used)
2. Input your proposed keywords into a keyword research tool (i.e. Google Adwords Keyword Tool, Wordtracker, Wordstream, etc)
3. Finalize your keyword list based on research (Create a list of both broad and targeted keywords)
4. Prepare them for launch (typically go after 3-4 related keywords per page)

Keyword Placement

For a website to successfully integrate into Google you first must tell us what a particular page is about. It’s important to get keywords on the right position on the page, but don’t overdo it. Here are the best places:

Title tag
Meta description and keywords
Website slogans
Navigation
Breadcrumb trails
H1, H2 and H3 tags
Bullet points
Alt text
Title attribute on links
The main website copy
Internal links
Footer links
URL’s
File / folder names

Search Engine Friendly Navigation

Having Search Engine Friendly Navigation basically means creating a structure that search engines can follow. A major culprit in search engines not being able to find a website is due to the links being images instead of text. So make sure you address this and all links and buttons are text-based. CSS3 can achieve the same effects that Photoshop can, which has contributed a lot in terms of modernizing the web and speeding up load times. Wherever possible, try to avoid the use of JavaScript, as search engines find it difficult to understand and may result in crawling issues. With the push towards mobile devices supporting the web, using advanced scripting languages on your website won’t fly so well, either.

URL’s and Filenames

Having an SEO-friendly URL means search engines can quickly identify what a page is about. It’s also a good tactic to include keywords in the URL as this increases Search Engine visibility.

An example of a not too friendly URL:

http://www.websitestore.com/products/item1?=20193

A better, more descriptive URL would be:

http://www.websitestore.com/home/furniture/ottomans

As you can see, the second option has a better selection of rich keywords, which will help the search engine in their efforts to index you.

It’s also a good habit to name your images using descriptive keywords. An appropriate file name can be the difference between your image appearing in Google images searches or not. For instance the name “1234.jpg” isn’t going to be as successful as “midcentury-furniture.jpg” when someone is looking for design inspiration.

Website Images

Images are often an overlooked aspect of SEO, but play just as an important role in the process.

You need to optimize your images to achieve faster loading times and subsequent search engine visibility.

Try to keep your images’ file size as small as possible so mobile visitors in addition to those with slow internet connections can get the same intended, fast experience.

An optimal image size is anywhere from 30-100kb and the best resolution is 72dpi.

You can also set the image size as part of the corresponding tag for the image.

It’s best to place your images on context in the page. The more relevant the text around your image, the better results you’ll get for rankings.

Place your images inside a folder named “images” or something similar so the final URL of the image looks something like this: /images/image.jpg.

Perfect Website Optimization explains how to incorporate keywords into your alt tag.

Social Media

Social Media should be part of your SEO strategy as building relationships and interacting with connections can help build your brand enormously. Not only that but it gives you exposure and helps build a trusted community and gain credibility.

Link building is perhaps the number one reason to jump on board the Social Media bandwagon: the process of visitors sharing links within their own network can result in a large number of inbound links. In summary, social media can provide an organization with an affordable channel that accomplishes results.

Get started by joining:

Facebook
Twitter
LinkedIn
Digg

Additional Resources

This guide by Google is a very helpful guide in learning about SEO.

55 Quick Seo Tips Even Your Mother Would Love.

Monitor where you stand with Google Toolbar and Alexa.

Source From: http://www.1stwebdesigner.com/design/design-seo-friendly-website/

HTTP Signed Requests with PHP

2011-12-26T19:10:00.000+05:30

What are signed HTTP requests?

Signed HTTP requests are simply a normal HTTP request, such as a GET or a POST, that happens to include a signature as part of the request. A signature is just a string of characters generated in a meaningful way. This signature can be used by the receiving party (ie. a REST service) to validate the request and ensure that it hasn't been tampered with.

What are signed requests good for?

In a nutshell, validating an HTTP request where restricted access to resources are necessary. For example, a service that allows someone to update their personal information needs to ensure that people can only update their own personal information. Signed requests ensure that the service that receives the data can verify that the sender is who they claim they are (or at least possesses the proper secret key, a de-facto assumption it is the right person).

Obviously, having someone log in and create a session is another method of verifying user identity, however, this is not always efficient or possible, especially with web services. As an example, every Facebook application developer gets a secret key when they create an application on Facebook. When Facebook sends information to someone's application, it will include a signed request that is only valid with that developer's key. By checking the signature, a developer can verify that a request came from Facebook, and isn't someone trying to fool their application. They also don't need to provide a complicated session procedure or have Facebook "log in" to their application; the signed request is enough.
What aren't signed requests good for?

Signed requests are not a form of encryption. If the data being sent is sensitive in nature, such that you wouldn't want it being sniffed in transit over a network connection, then SSL encrypted communication (HTTPS) is the way to go. For simple REST services however, often you just need to limit requests based on a user or other similar scope, and signed requests are sufficient for that.

A problem that signed requests can solve

Here is an example situation that has a security problem that can be solved by the use of signed requests. Let's say you operate a network of beer brewing web sites, and the brewers are allowed to send updates via a REST service you have provided. Each brewer has their own user id that they get when they sign up to your service. Bob's Brewery (user id 1234) wants to update their email address. The simplest of implementations might allow for a request to be sent like this: /user/update?email=newbob@example.com&userid=1234. However, if this was the only thing the REST service needed to update an email address, it would be trivial to cause serious mayhem. For example, Mr. Evil's Brewery could send in a simple request to change Bob's email address, just by finding Bob's ID somewhere, or even trying random ones:

/user/update?email=evil@example.org&userid=1
/user/update?email=evil@example.org&userid=12
/user/update?email=evil@example.org&userid=1234
etc.

Too easy! Obviously more security is needed, and this is where the concept of secret keys comes in.

Secret Keys

It is a common practice to assign each user a secret key that they use to interact with a web service, often called an API key, generally consisting of randomly generated characters. In this case, you could give Bob a secret key when he signs up with the brewery network, and it would be stored in your database along with the rest of his account information.

Here's where I often see confusion setting in. Many people think it is logical that the secret key be sent as part of the API request, because after all, it uniquely identifies the user and it was given only to that particular person. However, this is a security problem!

The thing about secret keys is that they have to remain secret, just like any password. As soon as a key is leaked, whoever finds it can impersonate that account, just as easily as Mr. Evil's Brewery did in the previous example. If you send a secret key as part of an HTTP request, it is no longer secret. You have just leaked it to whoever cared to be listening! A network sniffer could pick it up, or it could be recorded in proxy logs or web server logs that aren't secured. Perhaps your ISP is doing deep packet inspection, and a rogue employee makes off with the logs. Who knows!

The following is an example of this type of insecurity. Bob is sending his update request along with the secret key:

/user/update?email=newbob@example.com&userid=1234&secret_key=bobs-super-secret-key

Now, pretend that Bob goes to his local Tarborks coffee shop and jumps on the free open wireless connection. Mr. Evil happens to be there, and fires up his network sniffer program and starts watching all the HTTP traffic on the network. He sees Bob's request go out, since HTTP connections are not secure. Now he has Bob's secret key, and can make any kind of request he wants with it. Maybe he could even delete Bob's account with a request to /user/delete?userid=1234&secret_key=bobs-super-secret-key, or send insults to Bob's customers using a mail endpoint!

Sending the secret key as part of a network request is NOT safe. So how do we properly identify the sender if the user id can't be trusted and they can't send us their key? Well, you knew I'd get to it eventually... signed requests!
Signed HTTP Requests

To produce a signed HTTP request, the sender and the receiver must both know the rules on how to generate a signature. It can be any crazy method you care to dream up, but a common one is as follows:

The sender organizes the data they want to send in a logical way, such as sorting it alphabetically.
The data is run through a hashing algorithm using the secret key to produce a hash. Hashing algorithms produce short strings of characters that vary based on the input data, and the output is sufficiently unique such that varying the input data by even one character produces a completely different hash.
The hash is added to the original data and sent.
The receiver identifies the user and gets the secret key from their associated account information, and recreates the hash on the received data.
If the recreated hash matches the one included in the request, the request is valid.

To return to our Tarborks coffee shop scenario, the request going out might look like this now:

/user/update?email=newbob@example.com&userid=1234&sig=x1zz645

If Mr. Evil sniffs this request, he might be pretty pleased with himself and try to change it to /user/update?email=evil@example.org&userid=1234&sig=x1zz645. This request would be rejected by the server however, since the signature is now invalid! When Mr. Evil changed the request, he needed to change the signature to match. But since he doesn't have Bob's secret key, he can't generate a correct signature, for this request or any other he cares to make up. The only valid request he can possibly make is the exact same one he just sniffed, and that's not very malicious at all, since it's what Bob was trying to do anyway.
Get to the code already

Assuming Bob's user id is 1234, and the secret key you gave him is "bobs-super-secret-key", he might write the following PHP code.
User code
PHP:

    $USER_ID = "1234";
    $SECRET_KEY = "bobs-super-secret-key";

    /**
    * @param array $data Array of key/value pairs of data
    * @param string $secretKey
    * @return string A generated signature for the $data based on $secretKey
    */
    function generateSignature($data,$secretKey)
    {
        //sort data array alphabetically by key
        ksort($data);
        //combine keys and values into one long string
        $dataString = '';
        foreach($data as $key => $value) {
            $dataString .= $key.$value;
        }
        //lowercase everything
        $dataString = strtolower($dataString);
        //generate signature using the SHA256 hashing algorithm
        return hash_hmac("sha256",$dataString,$secretKey);
    }

    $bobsData = array(
        "userid" => $USER_ID,
        "email" => "newbob@example.com"
    );

    $sig = generateSignature($bobsData,$SECRET_KEY);
    //add signature to the outgoing data
    $bobsData['sig'] = $sig;
    //generate HTTP query string
    $queryString = http_build_query($bobsData);

    echo $queryString;

The code above outputs userid=1234&email=newbob%40example.com&sig=efffd9cc30a220f2981b5124e1caa44d91b85aa2d2181f5331f48ca719983c1d. That's the HTTP query string that Bob would send to the /user/update endpoint to change his email address. So how does the service verify the request?
Server-side code
PHP:

    if (empty($_REQUEST['userid'])) {
        throw new Exception("No user id was sent with the request.");
    }

    //look up the account associated with the value in $_REQUEST['userid']
    //and get the secret key for that account - implement as necessary
    $secretKey = getSecretKeyFromUserId($_REQUEST['userid']);

    $data = $_REQUEST;
    $receivedSignature = $data['sig'];
    //generate a signature using the data sent by the user, without the 'sig'
    //parameter of course. Note that the generateSignature() function is the
    //SAME ONE that the users would use!
    unset($data['sig']);
    $generatedSignature = generateSignature($data,$secretKey);

    if ($generatedSignature != $receivedSignature) {
        throw new Exception("Received signature is invalid!");
    }
    else {
        //continue on, knowing it is the right user making the request.
    }

There you have it. Signed requests!
Advanced Usage

The signature for a signed request can be sent in different ways. Some services, such as Amazon's S3 REST API, puts the signature in the HTTP headers. This is arguably a bit cleaner than including it in the parameters of an HTTP request, since the signature doesn't get mixed in with the data, and has implications for caching as well (browser caches and proxies). If you want to do it that way, you might have the user set a header as part of their HTTP request:
PHP:

    header("X-Brewery-Sig: ".$sig);

And the receiving server, instead of looking for the sig parameter in $_REQUEST['sig'] (and having to remove it before running the data through the generator function), would find it in:
PHP:

    $_SERVER['HTTP_X_BREWERY_SIG'];

Hope you found this useful!

Source From: http://www.phpvs.net/2011/12/24/http-signed-requests-with-php/

Useful .htaccess snippets

2011-11-07T18:14:00.000+05:30

.htaccess, the file which control the Apache webserver, is very useful and allows you to do a lot of things. In this article, I have compiled 10 .htaccess snippets that any web developer should have in his toolbox.

Remove www in url

For SEO reasons, you might always remove (or use) the www prefix in your urls. The following snippet will remove the www from your website url and redirect any url with the www to the non-www version.

RewriteEngine On
RewriteCond %{HTTP_HOST} !^your-site.com$ [NC]
RewriteRule ^(.*)$ http://your-site.com/$1 [L,R=301]

Source: http://css-tricks.com/snippets/htaccess/www-no-www/

Prevent hotlinking

Hotlinking is a bad practice that consist of using the images from another site on yours. When you’re hotlinked by someone else, your bandwidth is used for someone else profit. Of course, you may want to prevent hotlinkers. Just add the following snippet to your .htaccess file after replacing the example urls by your own urls.

RewriteEngine On
#Replace ?mysite\.com/ with your blog url
RewriteCond %{HTTP_REFERER} !^http://(.+\.)?mysite\.com/ [NC]
RewriteCond %{HTTP_REFERER} !^$
#Replace /images/nohotlink.jpg with your "don't hotlink" image url
RewriteRule .*\.(jpe?g|gif|bmp|png)$ /images/nohotlink.jpg [L]

Create custom error pages

Tired of the old errors pages of your site? Just create some html files with the look you want, upload them to your server, and add the following to your .htaccess file:

ErrorDocument 400 /errors/badrequest.html
ErrorDocument 401 /errors/authreqd.html
ErrorDocument 403 /errors/forbid.html
ErrorDocument 404 /errors/notfound.html
ErrorDocument 500 /errors/serverr.html

Source: http://css-tricks.com/snippets/htaccess/custom-error-pages/

Log PHP errors

This snippet is an interesting way to log errors from your php file into a log file. Just create a php_error.log file somewhere on your server, and add the snippet to your .htaccess file. Don’t forget to modify the log file location on line 7.

# display no errs to user
php_flag display_startup_errors off
php_flag display_errors off
php_flag html_errors off
# log to file php_flag log_errors on
php_value error_log /location/to/php_error.log

Source: http://css-tricks.com/snippets/htaccess/php-error-logging/

Remove file extensions from urls

File extensions may be useful to developers, but there’s absolutely no need for your site visitors to be able to see them. This snippet will remove the .html extension on any html files. Of course, this code can be easily adapted to remove extensions from other file extensions such as php.

RewriteEngine on
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_FILENAME}\.html -f
RewriteRule ^(.*)$ $1.html
# Replace html with your file extension, eg: php, htm, asp

Source: http://eisabainyo.net/weblog/2007/08/19/removing-file-extension-via-htaccess

Prevent directory listing

On your web server, when a directory do not have an index file, Apache automatically create a list of all files from the current directory. If you do not wish that anyone can see which files are on your server, just add the following code to your .htaccess file to prevent automatic directory listing.

Options -Indexes

Reduce pages weight by compressing static data

Do you know that it is possible to send compressed data to the visitors, which will be decompressed by the client? This code will definitely save you (and your visitor) bandwidth and reduce your pages weight.

AddOutputFilterByType DEFLATE text/html text/plain text/xml application/xml
 application/xhtml+xml text/javascript text/css application/x-javascript
BrowserMatch ^Mozilla/4 gzip-only-text/html
BrowserMatch ^Mozilla/4.0[678] no-gzip
BrowserMatch bMSIE !no-gzip !gzip-only-text/html

Automatically add utf-8 charset to files

In order to avoid encoding problems, you can force a specific encoding directly on your .htaccess file. That way, you’ll ensure that your html documents will always render correctly, even if your forget to add a directive on your html pages.

 AddDefaultCharset UTF-8

Source: http://www.askapache.com/htaccess/setting-charset-in-htaccess.html

How to Improve your Skills as a Programmer

2011-11-04T12:22:00.000+05:30

This will give you a few hints and some help to becoming a better programmer. So read on and enjoy! Programming can be a lot of fun if you follow these simple but efficient rules to make it that way.Otherwise there are lot of programmers out there who are unsatisfied with their programming skills.So lets get started..

Steps

[1]. Gather complete requirements.Think about how what you write will function; try to consider an efficient way of doing it.

[2]. Add Comments to your code.Whenever you feel your code needs some explanation, drop some comments in. Each function should be preceded by 1-2 lines describing the arguments and what it returns. (Comments should tell you why more often than what. Remember to update the comments when you update your code!)

[3]. Use naming conventions for variables.It will help you keep track of what type the variable is. e.g. for integer variables, intRowCounter; strings: strUserName. It doesn't matter what your naming convention is, but be sure that it is consistent and that your variable names are descriptive. (See Cautions and Warnings below)

[4]. Organize your code.Indent after each bracket, try putting spaces between a variable name and an operator such as addition, subtraction, multiplication, division, and even the equal sign (myVariable = 2 + 2).

[5]. Test.Try to think of anything that might prevent it from working correctly. Debug the errors you find.
* Write your tests to always include the following:
o Extremes: zero and max for positive values, empty string, null for every parameter.
o Meaningless values: Jibberish. Even if you don't think someone with half a brain might input that, test your software against it.
o Wrong values: Zero in a parameter that will be used in a division, negative when positive is expected or a square root will be calculated. Something that is not a number when the input type is a string, and it will be parsed for numeric value.

[6]. Practice. Practice. Practice.

[7]. Create a 'model' of your code that both the customers and the final operators can understand - a blueprint. Present it to them so they understand it and give them a chance to comment

[8]. Structure the project as a series of presentations and deployments. Dont plan in too much detail beyond the 1st couple of presesentations. Count on finding out new things about the brief every time you present or deploy. Count on the customers and operators changing their minds every time. Be ready for it. Use it. It will make the project actually worth completing.

[9]. Build a simple program then after you get the program the way you want it to be, then start adding new features to it. An example of this would be to build a number guessing program where the program will generate a random number every time you load the program then you have to guess the number. Then you can add to this by having the program be able to have a new random number with the press of a button, having you not being able to guess after a certain number of failed guesses, etc. This will not only help you with upgrading a program, this will also help you determine if there are any problems with the program prior to the upgrade.

Tips n Tricks

Start small, aim for things that you most likely will be able to achieve, and work your way up.
It is very important that you use TAB spacing to differentiate lines of code that are encapsulated (if, for, while, etc...) to make it easier to determine if you are still inside the encapsulation. This makes it much easier to read.
Tutorial sites are an excellent resource as well.
Reading the work of others (source code) is an excellent means of improving ones skills.
Use syntax-highlighting in your editor, it really helps.
People can often be a good resource for information, particularly when starting out.
Keep your past work, it is a good point of reference.
Change one thing at a time when debugging and then test your corrections before moving on the next item.
After each bigger segment of work, take a break doing something else, then review what you have written with a fresh mind; rethink and rewrite it, making it more effective and elegant by using less code. Repeat until perfect.
A program such as Visual Basic .Net can cost a lot of money. If you MUST use visual basic, go out and download Visual Studio Express Beta 2 2005 from www.microsoft.com or you may buy the student or learning editions.
Remember programming languages like Java, PHP and Python, available at no cost.
Have fellow programmers read your code. If you don't know any send your code to professionals. You would be surprised what they know that you may have never thought of before! Can't find a professional? There are plenty of forums on www.myspace.com where most of the users are good hearted programmers that offer constructive criticism.
Double check spelling. A slight mistake can cause a lot of stress.
Use version control management. Tools like CVS or SVN make it even easier to track code changes and bugs. Once you get used to it you wont look back.
Use an IDE (Integrated Development Environment).
Customers and bosses aren't nearly concerned with how your program works nearly so much as they are with how well it works. Think bottom line. Clients are intelligent, but busy. They won't care what kind of data structures you're using, but they will care if it speeds up performance by 10%.

CAUTION and WARNINGS !!!

In step three, this Hungarian notation (indicating a variable's type with its name) is widely avoided by many programmers. It can easily lead to inconsistency when edited or ported, and can become quite confusing. Try to avoid this as much as possible
Copying and pasting others' code is a bad habit, especially if you weren't supposed to see the source. But all things considered, taking small portions from an open source program could be a learning experience. Just don't completely copy a program and attempt to take credit for it.
Save your work frequently as you go along or you risk losing hours and hours of work to a computer crash or lock-up.
Always test your code
Don't copy code from another program unless you have permission or the license permits it, like Open Source licenses.

Things You Will DEFINITELY Need

Ideas
IDE (Integrated Development Environment)
Computer
Reference books or web tutorials

Source from: http://www.theprohack.com/2008/09/how-to-improve-your-skills-as.html

Useful PHP code snippets for PHP developers

2011-09-21T13:19:00.000+05:30

1. Send Mail using mail function in PHP

<?php

$to = "anjvelu@gmail.com";

$subject = "Send Mail";

$body = "Body of your message here you can use HTML too.";

$headers = "From: Velu\r\n";

$headers .= "Reply-To: info@yoursite.com\r\n";

$headers .= "Return-Path: info@yoursite.com\r\n";

$headers .= "X-Mailer: PHP5\n";

$headers .= 'MIME-Version: 1.0' . "\n";

$headers .= 'Content-type: text/html; charset=iso-8859-1' . "\r\n";

mail($to,$subject,$body,$headers);

2. Base64 Encode and Decode String in PHP

function base64url_encode($plainText) {
$base64 = base64_encode($plainText);
$base64url = strtr($base64, '+/=', '-_,');
return $base64url;
}

function base64url_decode($plainText) {
$base64url = strtr($plainText, '-_,', '+/=');
$base64 = base64_decode($base64url);
return $base64;
}

3. Get Remote IP Address in PHP

4. Parsing XML in easy way using PHP

//this is a sample xml string
$xml_string="<?xml version='1.0'?>
<moleculedb>
<molecule name='Benzine'>
<symbol>ben</symbol>
<code>A</code>
</molecule>
<molecule name='Water'>
<symbol>h2o</symbol>
<code>K</code>
</molecule>
</moleculedb>";

//load the xml string using simplexml function
$xml = simplexml_load_string($xml_string);

//loop through the each node of molecule
foreach ($xml->molecule as $record)
{
//attribute are accessted by
echo $record['name'], ' ';
//node are accessted by -> operator
echo $record->symbol, ' ';
echo $record->code, '<br />';
}

5. Simple page caching
The following code snippet is very simple, but works well for small websites.

<?php
// define the path and name of cached file
$cachefile = 'cached-files/'.date('M-d-Y').'.php';
// define how long we want to keep the file in seconds. I set mine to 5 hours.
$cachetime = 18000;
// Check if the cached file is still fresh. If it is, serve it up and exit.
if (file_exists($cachefile) && time() - $cachetime < filemtime($cachefile)) {
 include($cachefile);
 exit;     }
// if there is either no file OR the file to too old, render the page and capture the HTML.
ob_start();
?>
<html>
  <body>
   output all your html here.
  </body>
  </html>
<?php
// We're done! Save the cached content to a file
$fp = fopen($cachefile, 'w');
fwrite($fp, ob_get_contents());
fclose($fp);
// finally send browser output
ob_end_flush();
?>

6.Force file download

function downloadFile($file)
{
$file_name = $file;
$mime = 'application/force-download';
header('Pragma: public'); // required
header('Expires: 0'); // no cache
header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
header('Cache-Control: private',false);
header('Content-Type: '.$mime);
header('Content-Disposition: attachment; filename="'.basename($file_name).'"');
header('Content-Transfer-Encoding: binary');
header('Connection: close');
readfile($file_name); // push it out
exit();
}

Some usefull commands for Linux

2011-09-14T15:58:00.000+05:30

Open your terminal window,

1. Read linux system IP address in a shell script:
# ifconfig | grep 'inet addr:'| grep -v '127.0.0.1' | cut -d: -f2 | awk '{ print $1}'

2. Some process activity commands:
# top
The top program provides a dynamic real-time view of a running system i.e. actual process activity. By default, it displays the most CPU-intensive tasks running on the server and updates the list every five seconds.

3. Find out who is logged on and what they are doing
# w
The command displays information about the users currently on the machine, and their processes.

4. How long the system has been running
# uptime

5. The current running process information
# ps
And also try
# ps -A
     The above one is shows all currently running process.

6. Memory usages
# free
It will shows the total amount of free and used physical and swap memory in the system, as well as the buffers used by the kernel.

7. check the hard disk usages
# df -h
This will output the usage of each partition in the server.

8. The specific directory memory usages size list
# du -sh /home/

9. If you want to list all the subdirectory sizes under /home, run the following command:
# du -sh /home/*

10. Check the system partition information
# fdisk -l

11. Check the root user cronjobs information
#crontab -l

12. Remote file download
scp user@remote_host:remote_file local_file
ex: scp -P 23 vvelu@65.00.0.0:/home/velu/temp/test.txt test.txt

13. Upload file to Remote
scp local_file user@remote_host:remote_file
ex: scp -P 23 ./test.txt vvelu@60.0.0.0:/home/vvelu/tmp/test.txt

Ubuntu useful commands

12. Remove partial packages from the system
sudo apt-get autoclean

13.To clean remove .deb packages that apt caches when you install/update programs
sudo apt-get clean

Google APIs Client Library for PHP (Beta)

2011-09-09T14:46:00.000+05:30

The Google APIs Client Library for PHP has officially reached Beta.

The Google API PHP client supports the following Google APIs right now, with more on the way.

Buzz API - Sample
Books API - Sample
Latitude API - Sample
Page Speed Online API - Sample
Tasks API - Sample
URL Shortener API - Sample

To grab the latest version of the library, simply run the following commands:

curl "http://google-api-php-client.googlecode.com/files/google-api-php-client-0.4.1.tar.gz" -O

tar -xvf google-api-php-client-0.4.1.tar.gz

cd google-api-php-client/examples/

Here is some sample code that demonstrates how to use the library and the Google Books API to search for and print the titles of free ebooks by Henry David Thoreau:

<?php
require_once 'path/to/src/apiClient.php';
require_once 'path/to/src/contrib/apiBooksService.php';

$client = new apiClient();
$client->setApplicationName("My_Books_API_Example");
$service = new apiBooksService($client);

$optParams = array('filter' => 'free-ebooks');
$results = $service->volumes->listVolumes('Henry David Thoreau', $optParams);

foreach ($results['items'] as $item) {
  print($item['volumeInfo']['title'] . '<br>');
}

Blog: The official Google Code blog
Post: Google APIs Client Library for PHP (Beta)
Link: http://googlecode.blogspot.com/2011/09/google-apis-client-library-for-php-beta.html

Manually installing LAMP (Apache 2, MySQL, PHP 5) and phpMyAdmin on Ubuntu 10.10

2011-09-08T12:52:00.000+05:30

In this guide I will show you how to install a LAMP system. LAMP stands for Linux, Apache, MySQL, PHP. The guide is intended to help those who have very little knowlegde of using Linux.

First update your ubuntu packages,
1. Open up the Terminal (Applications > Accessories > Terminal).
2. Copy/Paste the following line of code into Terminal and then press enter:

sudo apt-get update

2. The Terminal will then ask you for you're password, type it and then press enter.

Install Apache

To start off we will install Apache.
1. Copy/Paste the following line of code into Terminal and then press enter:

sudo apt-get install apache2

Testing Apache

To make sure everything installed correctly we will now test Apache to ensure it is working properly.
1. Open up any web browser and then enter the following into the web address:

http://localhost/

You should see a folder entitled apache2-default/. Open it and you will see a message saying "It works!" , congrats to you!

Install PHP

In this part we will install PHP 5.
Step 1. Again open up the Terminal (Applications > Accessories > Terminal).
Step 2. Copy/Paste the following line into Terminal and press enter:

sudo apt-get install

php5 php5-dev libapache2-mod-php5 php5-curl 
php5-gd php5-idn php-pear php5-imagick php5-imap php5-mcrypt 
php5-memcache php5-ps php5-pspell php5-recode php5-snmp php5-tidy 
php5-xmlrpc php5-xsl php5-common

Step 3. In order for PHP to work and be compatible with Apache we must restart it. Type the following code in Terminal to do this:

sudo /etc/init.d/apache2 restart

Test PHP

To ensure there are no issues with PHP let's give it a quick test run.
Step 1. In the terminal copy/paste the following line:

sudo gedit /var/www/testphp.php

This will open up a file called phptest.php.
<?php phpinfo(); ?>Step 2. Copy/Paste this line into the phptest file:

Step 3. Save and close the file.
Step 4. Now open you're web browser and type the following into the web address:

http://localhost/testphp.php

Install MySQL

To finish this guide up we will install MySQL. (Note - Out of Apache and PHP, MySQL is the most difficult to set up. I will provide some great resources for anyone having trouble at the end of this guide.)
Step 1. Once again open up the amazing Terminal and then copy/paste this line:

sudo apt-get install mysql-server mysql-client php5-mysql

You will be prompted to create a password for MySQL.

Now just restart Apache and you are all set!

sudo /etc/init.d/apache2 restart

Install Phpmyadmin
Step 1. Once again open up the amazing Terminal and then copy/paste this line:

sudo apt-get install phpmyadmin

You’ll be prompted by a dialog at some point, make sure to choose Apache 2. After that you need to answer a few more dialogs, the default is fine. Set the passwords accordingly and your done.

You can access phpMyAdmin now from this address: http://localhost/phpmyadmin/

To login to phpMyAdmin use root as the user and the password you entered previously.

Don’t forget to restart Apache:

sudo /etc/init.d/apache2 restart

Enjoy..........

velu liked web (programs, article, news, etc)

Few Useful Git Commands with Example for Beginners

git config

git init

git add

git commit

git status

git branch

Debounce in Javascript and React

Define basic debounce function with Javascript

Implement the debounce function

Implement the debounce function with React

Captcha - PHP GD Library

Prerequisites:

What you need to know about Captcha

Registration form with Captcha using PHP GD library

HTML Contact Form with Captcha

Creating The Captcha Page

Captcha validation for the Registration Form

Conclusion

Increasing Website Page Load Speeds

By increasing your website speed, you can: increase user experience, have higher conversions, promote engagement, and generate even higher search rankings.

Things to consider

Eliminate render-blocking JavaScript and CSS in above-the-fold content

Optimize images

Leverage browser caching

Reduce server response time

Minify CSS, HTML, JavaScript

PHP Time Ago

How to use local storage for JavaScript

What is local storage?

The HTML

The JavaScript

Store an Array in localStorage localStorage only supports strings. Use JSON.stringify() and JSON.parse(). for store and retrieve the array.

Browser support

Conclusion

PHP MySQL – Get Next Auto Increment Value of a Table

As a Function

Robot.txt

Useful snippets for php developers

Extract keywords from a webpage

Find All Links on a Page

Create Data URI’s

Download & save a remote image on your server

Detect browser language

Display number of Facebook fans in full text

How to send email from the Linux command line

MUTT

adfasdasdMAIL

MUTT

Read more at http://www.simplehelp.net/2008/12/01/how-to-send-email-from-the-linux-command-line/#ZW60emwX4KkihuKF.99MAIL

MUTT

Read more at http://www.simplehelp.net/2008/12/01/how-to-send-email-from-the-linux-command-line/#ZW60emwX4KkihuKF.99MAIL

MUTT

Some useful tools for web developers

Autocomplete Textbox with JQuery

Add Proxy Context Stream For PHP

PHP Script show all errors

Backup and Restore MySQL Database Using mysqldump

How To Backup MySQL database

1. Backup a single database:

2. Backup multiple databases:

3. Backup all the databases:

4. Backup a specific table:

How To Restore MySQL database

1. Restore a database

2. Backup a local database and restore to remote server using single command:

phpMyAdmin - To change the authentication timeout value and increase the default number of result in browse mode.

How to Install and Run Internet Explorer 7/8 On Ubuntu 11.04/11.10

6 Tips For Designing an SEO Friendly Website

Keywords

Keyword Placement

Search Engine Friendly Navigation

URL’s and Filenames

Website Images

Social Media

Additional Resources

HTTP Signed Requests with PHP

Useful .htaccess snippets

Remove www in url

Store an Array in localStorage
`localStorage` only supports strings. Use `JSON.stringify()` and `JSON.parse()`. for store and retrieve the array.