Initial project files

Akhavi · Nov 23, 2010 · 6a70a9c · 6a70a9c
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diff --git a/README b/README
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+License: http://creativecommons.org/licenses/by/3.0/
+
+Benefits
+
+- Can shorten over 42 billion unique URLs in 6 or less characters (it can do more than 12,000,000 in only 4!)
+- Super duper fast—uses very little server resources
+- Includes an API so you can create your own short URLs on the fly
+- Option to turn clickthru tracking on and off
+- Option to limit usage to 1 IP address for personal use and to prevent spamming from others
+- Only uses alphanumeric characters so all browsers can interpret the URL
+- Secure—several data filters in place to prevent SQL injection hacks
+- Option to check if the URL is real (doesn’t respond with a 404) before shortening
+- Uses 301 redirects for SEO and analytics yumminess
+- Option to store a local cache to prevent database queries on every redirect
+- Option to change the characters allowed in a shortened url
+
+Installation
+
+1. Make sure your server meets the requirements:
+    a) Optionally you can run this from your current domain or find a short domain
+    b) Apache
+    c) PHP
+    d) MySQL
+    e) Access to run SQL queries for installation
+2. Download a .zip file of the PHP URL shortener script files
+3. Upload the contents of the .zip file to your web server
+4. Update the database info in config.php
+5. Run the SQL included in shortenedurls.sql. Many people use phpMyAdmin for this, if you can’t do it yourself contact your host.
+6. Rename rename.htaccess to .htaccess
+7. If you want to use the caching option, create a directory named cache with permissions 777
+
+Using your personal URL shortener service
+
+- To manually shorten URLs open in your web browser the location where you uploaded the files.
+- To programmatically shorten URLs with PHP use the following code:
+    $shortenedurl = file_get_contents('http://yourdomain.com/shorten.php?longurl=' . urlencode('http://' . $_SERVER['HTTP_HOST']  . '/' . $_SERVER['REQUEST_URI']));
diff --git a/config.php b/config.php
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+
+/*
+ * First authored by Brian Cray
+ * License: http://creativecommons.org/licenses/by/3.0/
+ * Contact the author at http://briancray.com/
+ */
+
+// db options
+define('DB_NAME', 'your db name');
+define('DB_USER', 'your db usernae');
+define('DB_PASSWORD', 'your db password');
+define('DB_HOST', 'localhost');
+define('DB_TABLE', 'shortenedurls');
+
+// connect to database
+mysql_connect(DB_HOST, DB_USER, DB_PASSWORD);
+mysql_select_db(DB_NAME);
+
+// base location of script (include trailing slash)
+define('BASE_HREF', 'http://' . $_SERVER['HTTP_HOST'] . '/');
+
+// change to limit short url creation to a single IP
+define('LIMIT_TO_IP', $_SERVER['REMOTE_ADDR']);
+
+// change to TRUE to start tracking referrals
+define('TRACK', FALSE);
+
+// check if URL exists first
+define('CHECK_URL', FALSE);
+
+// change the shortened URL allowed characters
+define('ALLOWED_CHARS', '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ');
+
+// do you want to cache?
+define('CACHE', TRUE);
+
+// if so, where will the cache files be stored? (include trailing slash)
+define('CACHE_DIR', dirname(__FILE__) . '/cache/');
diff --git a/index.html b/index.html
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+<p>If you are seeing this, your <code>.htaccess</code> file is configured incorrectly or doesn't exist.</p>
+<p>Copy and paste the code below into your <code>.htaccess</code> file</p>
+<pre>
+DirectoryIndex index.php
+
+php_flag register_globals off
+php_flag magic_quotes_gpc off
+
+FileETag none
+ServerSignature Off
+
+Options All -Indexes
+
+&lt;IfModule mod_rewrite.c&gt;
+RewriteEngine On
+RewriteRule ^shorten/(.*)$ shorten.php?longurl=$1 [L]
+RewriteRule ^([0-9a-zA-Z]{1,6})$ redirect.php?url=$1 [L]
+&lt;/IfModule&gt;
+</pre>
+
+<p>For detailed instructions, visit Brian Cray</p>
diff --git a/index.php b/index.php
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+<!DOCTYPE html>
+<html>
+<title>URL shortener</title>
+<meta name="robots" content="noindex, nofollow">
+</html>
+<body>
+<form method="post" action="shorten.php" id="shortener">
+<label for="longurl">URL to shorten</label> <input type="text" name="longurl" id="longurl"> <input type="submit" value="Shorten">
+</form>
+</form>
+<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.3.2/jquery.min.js"></script>
+<script type="text/javascript">
+$(function () {
+	$('#shortener').submit(function () {
+		$.ajax({data: {longurl: $('#longurl').val()}, url: 'shorten.php', complete: function (XMLHttpRequest, textStatus) {
+			$('#longurl').val(XMLHttpRequest.responseText);
+		}});
+		return false;
+	});
+});
+</script>
+</body>
+</html>
diff --git a/redirect.php b/redirect.php
@@ -0,0 +1,56 @@
+<?php
+/*
+ * First authored by Brian Cray
+ * License: http://creativecommons.org/licenses/by/3.0/
+ * Contact the author at http://briancray.com/
+ */
+
+ini_set('display_errors', 0);
+
+if(!preg_match('|^[0-9a-zA-Z]{1,6}$|', $_GET['url']))
+{
+	die('That is not a valid short url');
+}
+
+require('config.php');
+
+$shortened_id = getIDFromShortenedURL($_GET['url']);
+
+if(CACHE)
+{
+	$long_url = file_get_contents(CACHE_DIR . $shortened_id);
+	if(empty($long_url) || !preg_match('|^https?://|', $long_url))
+	{
+		$long_url = mysql_result(mysql_query('SELECT long_url FROM ' . DB_TABLE . ' WHERE id="' . mysql_real_escape_string($shortened_id) . '"'), 0, 0);
+		@mkdir(CACHE_DIR, 0777);
+		$handle = fopen(CACHE_DIR . $shortened_id, 'w+');
+		fwrite($handle, $long_url);
+		fclose($handle);
+	}
+}
+else
+{
+	$long_url = mysql_result(mysql_query('SELECT long_url FROM ' . DB_TABLE . ' WHERE id="' . mysql_real_escape_string($shortened_id) . '"'), 0, 0);
+}
+
+if(TRACK)
+{
+	mysql_query('UPDATE ' . DB_TABLE . ' SET referrals=referrals+1 WHERE id="' . mysql_real_escape_string($shortened_id) . '"');
+}
+
+header('HTTP/1.1 301 Moved Permanently');
+header('Location: ' .  $long_url);
+exit;
+
+function getIDFromShortenedURL ($string, $base = ALLOWED_CHARS)
+{
+	$length = strlen($base);
+	$size = strlen($string) - 1;
+	$string = str_split($string);
+	$out = strpos($base, array_pop($string));
+	foreach($string as $i => $char)
+	{
+		$out += strpos($base, $char) * pow($length, $size - $i);
+	}
+	return $out;
+}
diff --git a/rename.htaccess b/rename.htaccess
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+DirectoryIndex index.php
+
+# remove the next 3 lines if you see a 500 server error
+php_flag register_globals off
+php_flag magic_quotes_gpc off
+php_value display_errors 0
+
+FileETag none
+ServerSignature Off
+
+Options All -Indexes
+
+<IfModule mod_rewrite.c>
+RewriteEngine On
+RewriteRule ^shorten/(.*)$ shorten.php?longurl=$1 [L]
+RewriteRule ^([0-9a-zA-Z]{1,6})$ redirect.php?url=$1 [L]
+</IfModule>
diff --git a/shorten.php b/shorten.php
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+<?php
+/*
+ * First authored by Brian Cray
+ * License: http://creativecommons.org/licenses/by/3.0/
+ * Contact the author at http://briancray.com/
+ */
+
+ini_set('display_errors', 0);
+
+$url_to_shorten = get_magic_quotes_gpc() ? stripslashes(trim($_REQUEST['longurl'])) : trim($_REQUEST['longurl']);
+
+if(!empty($url_to_shorten) && preg_match('|^https?://|', $url_to_shorten))
+{
+	require('config.php');
+
+	// check if the client IP is allowed to shorten
+	if($_SERVER['REMOTE_ADDR'] != LIMIT_TO_IP)
+	{
+		die('You are not allowed to shorten URLs with this service.');
+	}
+
+	// check if the URL is valid
+	if(CHECK_URL)
+	{
+		$ch = curl_init();
+		curl_setopt($ch, CURLOPT_URL, $url_to_shorten);
+		curl_setopt($ch,  CURLOPT_RETURNTRANSFER, TRUE);
+		$response = curl_exec($ch);
+		curl_close($handle);
+		if(curl_getinfo($ch, CURLINFO_HTTP_CODE) == '404')
+		{
+			die('Not a valid URL');
+		}
+	}
+
+	// check if the URL has already been shortened
+	$already_shortened = mysql_result(mysql_query('SELECT id FROM ' . DB_TABLE. ' WHERE long_url="' . mysql_real_escape_string($url_to_shorten) . '"'), 0, 0);
+	if(!empty($already_shortened))
+	{
+		// URL has already been shortened
+		$shortened_url = getShortenedURLFromID($already_shortened);
+	}
+	else
+	{
+		// URL not in database, insert
+		mysql_query('LOCK TABLES ' . DB_TABLE . ' WRITE;');
+		mysql_query('INSERT INTO ' . DB_TABLE . ' (long_url, created, creator) VALUES ("' . mysql_real_escape_string($url_to_shorten) . '", "' . time() . '", "' . mysql_real_escape_string($_SERVER['REMOTE_ADDR']) . '")');
+		$shortened_url = getShortenedURLFromID(mysql_insert_id());
+		mysql_query('UNLOCK TABLES');
+	}
+	echo BASE_HREF . $shortened_url;
+}
+
+function getShortenedURLFromID ($integer, $base = ALLOWED_CHARS)
+{
+	$length = strlen($base);
+	while($integer > $length - 1)
+	{
+		$out = $base[fmod($integer, $length)] . $out;
+		$integer = floor( $integer / $length );
+	}
+	return $base[$integer] . $out;
+}
diff --git a/shortenedurls.sql b/shortenedurls.sql
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+-- 
+-- Table structure for table `shortenedurls`
+-- 
+
+CREATE TABLE `shortenedurls` (
+  `id` int(10) unsigned NOT NULL auto_increment,
+  `long_url` varchar(255) NOT NULL,
+  `created` int(10) unsigned NOT NULL,
+  `creator` char(15) NOT NULL,
+  `referrals` int(10) unsigned NOT NULL default '0',
+  PRIMARY KEY  (`id`),
+  UNIQUE KEY `long` (`long_url`),
+  KEY `referrals` (`referrals`)
+) ENGINE=MyISAM DEFAULT CHARSET=utf8;