phoenixheart - portfolio & more » twitter http://www.phoenixheart.net phoenixheart - portfolio & more Wed, 23 Mar 2011 09:47:25 +0000 en hourly 1 http://wordpress.org/?v=3.1 Write your own URL shortener http://www.phoenixheart.net/2009/06/write-your-own-url-shortener/ http://www.phoenixheart.net/2009/06/write-your-own-url-shortener/#comments Thu, 04 Jun 2009 11:53:37 +0000 An http://www.phoenixheart.net/?p=305 With Twitter and its 140 characters limit leading all the trends, URL shortening services are in extremely high demand. We have seen TinyURL in the past, now Bit.ly, Is.gd, Tr.im and dozens of others are joining the party to share the cake. Honestly saying, to me they’re all the same (except for ➡.ws for its cool name). With that being said however, it is interesting how they are doing it out there – what mechanism / algorithm / buzzword-here?

I curiously did some “research”es (well, another buzzword), and it seems in order to create the shorten URLs they are following the same steps:

  1. Insert the original (long) URL into the database
  2. Get the insert ID. If the URL already exists, take its row ID. Let’s say we got 123456.
  3. Convert the ID 123456 into something even shorter, let’s say “am4k”
  4. Make use of Apache’s mod_rewrite so that any request to http://host.com/am4k will reach http://host.com/redir_script.php?code=am4k instead.
  5. In redir_script.php the value “am4k” is converted back into base10′s 123456 and the corresponding URL is queried back from database
  6. If a URL is found, redirect the request to it.

It is simple enough… except for step 3 and 4. Which conversion is there, and how is the .htaccess written?

So I did some other buzzword-here, and it turned out base36 encoding is taking place. According to Wikipedia, “the choice of 36 is convenient in that the digits can be represented using the Arabic numerals 0-9 and the Latin letters A-Z”. There is a handy conversion table too:

Decimal 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
Base 36 0 1 2 3 4 5 6 7 8 9 A B C D E F G H
Decimal 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35
Base 36 I J K L M N O P Q R S T U V W X Y Z

Even better, PHP takes only one line of code to convert between decimal and base36, as shown on the same Wiki page:

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$base_36 = "ZAQFG"; //Sample Base 36 Number
$decimal = "7654321"; //Sample Decimal Number
echo base_convert($base_36,36,10); //Outputs $base_36 converted to decimal
echo base_convert($decimal,10,36); //Outputs $decimal converted to base 36

In our example, 123456 will be converted into its tidy equivalent base36 2n9c (not am4k, my very bad).

As for the mod_rewrite thing, as I am not a .htaccess master, I copied this thing that has been working perfectly so far from CodeIgniter forum:

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RewriteEngine On
RewriteBase /
 
#Checks to see if the user is attempting to access a valid file,
#such as an image or css document, if this isn't true it sends the
#request to redir.php.
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ redir.php?code=$1 [L]
 

With this, all of the hardest parts are done, leave the remains being simple MySQL database, queries and HTML form handling. To save you from getting boring, I’ll omit it.

Instead, let’s see a demo hereThe source code of the demo are can be downloaded from the same server

]]> http://www.phoenixheart.net/2009/06/write-your-own-url-shortener/feed/ 6 Code snippet #1 – Get Latest Tweet http://www.phoenixheart.net/2009/05/code-snippet-1-get-latest-tweet/ http://www.phoenixheart.net/2009/05/code-snippet-1-get-latest-tweet/#comments Wed, 06 May 2009 12:29:41 +0000 An http://www.phoenixheart.net/?p=271 Ok so I’m following some guy’s recommendation (sorry, I really forgot his name as well as his blog address) to try to post something useful even when I don’t have anything to blog about. How about a series of code snippets? To some they are old but to the others they may help – for example to myself two months later that is.

Code Snippet #1 – Get Latest Tweet

Purpose

  • Get your latest tweet from Twitter to show up instead of an unconvincing “Follow Me” link -or-
  • Display your idol’s latest tweet to wow your readers

Requirements

  • A Twitter account. Don’t have one? Head here or here

The Code

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<?php
 
// the function
/**
 * @desc Get latest tweet from a Twitter account
 * @param string The account's username
 * @return string The tweet
 */
function get_latest_tweet($username)
{
    $url = "http://search.twitter.com/search.atom?q=from:$username&rpp=1";
    $content = file_get_contents($url);
    $content = explode('<content type="html">', $content);
    $content = explode('</content>', $content[1]);
    return html_entity_decode($content[0]);
}
 
// now use it
$my_username = 'Phoenixheart';
echo get_latest_tweet($my_username);
?>
]]> http://www.phoenixheart.net/2009/05/code-snippet-1-get-latest-tweet/feed/ 17 To twitter or not to twitter http://www.phoenixheart.net/2009/02/to-twitter-or-not-to-twitter/ http://www.phoenixheart.net/2009/02/to-twitter-or-not-to-twitter/#comments Thu, 05 Feb 2009 02:50:51 +0000 An http://www.phoenixheart.net/?p=221 Like almost everyone here, I have my Twitter account too, which I created long ago. Thing is, I don’t exactly know what’s it about (what a shame). Thaya he told me that it’s some kind of chatting, just less annoying and more useful, but still I don’t understand how people can keep a web page open like 8 hours a day and type in such as “I’m reading this {TinyURL}”, “I’m listening to this {TinyURL}” :D

So recently I see more and more people are following me on Twitter. This is like that, maybe, I should seriously start twittering and let them know that I should start twittering and let them know that I should start… oh well.

By having someone “following” you and reading your updates, kind of, make you feel more important. I don’t think I can get used to it (easily).

But what do you think? Are you following me on Twitter? ;)

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