CPANのshorten_urlをJavaScript/PHPで移植。

shorten_url.js

/**
 * Make shorten url.
 *
 * work fine on node.js.
 *
 * via http://search.cpan.org/~alexbio/Algorithm-URL-Shorten-0.06/lib/Algorithm/URL/Shorten.pm
 * based version 0.06.
 */

/*

	How to use: 

	var shorten = require('shorten_url');
	var shorts = shorten.shorten_url('http://perl.org');
	console.log(shorts);


	result :

	iqGzim
	S515va
	qmKrq8
	HXv4HD

*/


var crypto = require('crypto');

/**
 * make md5 string
 * ex.) 912ec803b2ce49e4a541068d495ab570
 */
function md5_hex(data) {
	if (!data) return null;
	if (typeof data !== 'string') {
		data = data.toString();
	}

	var hex = crypto.createHash('md5').
		update(data).
		digest('hex');

	return hex;
}

exports.shorten_url = function (url) {
	var chars = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9'];

	var hex = md5_hex(url);

	var output = [];
	for (var i=0; i < hex.length / 8; i++) {
		var sub_hex = hex.substr(i * 8, 8);
		var toInt = parseInt(sub_hex, 16);

		var out = '';
		for (var j=0; j < 6; j++) {
			var val = 0x3D & toInt;
			out += chars[val];
			toInt = toInt >> 5;
		}

		output.push(out);
	}

	return output;
}

/**
 * Copyright 2011 Alessandro Ghedini.
 * 
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of either: the GNU General Public License as published
 * by the Free Software Foundation; or the Artistic License.
 * 
 * See http://dev.perl.org/licenses/ for more information.
 *
 *
 * forked by @esperia09
 */

shorten_url.php

<?php

function shorten_url($data) {
  $chars = 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789';
	$hex = hash('md5', $data);

	$output = array();
	for ($i = 0; $i<strlen($hex) / 8; $i++) {
		$sub_hex = substr($hex, $i * 8, 8);
		$int = hexdec($sub_hex);

		$out = '';
		for ($j = 0; $j < 6; $j++) {
			$val = 0x3D & $int;
			$out .= $chars{$val};
			$int = $int >> 5;
		}

		$output[] = $out;
	}

	return $output;
}

//var_dump(shorten_url('http://perl.org'));
/*
array(4) {
  [0]=>
  string(6) "iqGzim"
  [1]=>
  string(6) "S515va"
  [2]=>
  string(6) "qmKrq8"
  [3]=>
  string(6) "HXv4HD"
}
*/