Preg-replace - 替换除域及其子域之外的所有URL

Question

I've a Glype proxy and I want not parse external URLs. All URLs on the page are automatically converted to: http://proxy.com/browse.php?u=[URL HERE] . Example: If I visit The Pirate Bay on my proxy, then I want not to parse the following URLs:

ByteLove.com (Not to: http://proxy.com/browse.php?u=http://bytelove.com&b=0)
BayFiles.com (Not to: http://proxy.com/browse.php?u=http://bayfiles.com&b=0)
BayIMG.com (Not to: http://proxy.com/browse.php?u=http://bayimg.com&b=0)
PasteBay.com (Not to: http://proxy.com/browse.php?u=http://pastebay.com&b=0)
Ipredator.com (Not to: http://proxy.com/browse.php?u=https://ipredator.se&b=0)
etc.

Of course I want to keep the internal URLs, so:

thepiratebay.se/browse (To: http://proxy.com/browse.php?u=http://thepiratebay.se/browse&b=0)
thepiratebay.se/top (To: http://proxy.com/browse.php?u=http://thepiratebay.se/top&b=0)
thepiratebay.se/recent (To: http://proxy.com/browse.php?u=http://thepiratebay.se/recent&b=0)
etc.

Is there a preg_replace to replace all URL's except thepiratebay.se and there subdomains (as in the example)? An other function is also welcome. (Such as domdocument, querypath, substr or strpos. Not str_replace because then I should define all URLs)

I've found something, but I'm not familiar with preg_replace:

$exclude = '.thepiratebay.se';
$pattern = '(https?\:\/\/.*?\..*?)(?=\s|$)';
$message= preg_replace("~(($exclude)?($pattern))~i", '$2<a href="$4" target="_blank">$5</a>$6', $message);

Answer 1

you can use preg_replace_callback() to execute a callback function for every match. In that function you can determine if the matched string should be converted or not.

<?php
$string = 'http://foobar.com/baz and http://example.org/bumm';
$pattern = '#(https?\:\/\/.*?\..*?)(?=\s|$)#i';
$string = preg_replace_callback($pattern, function($match) {
    if (stripos($match[0], 'example.org/') !== false) {
        // exclude all URLs containing example.org
        return $match[0];
    } else {
        return 'http://proxy.com/?u=' . urlencode($match[0]);
    }
}, $string);

echo $string, "\n";

(Example is using PHP 5.3 closure notation)

Answer 2

I'll guess you would need to provide a whitelist to tell which domains should be proxied:

$whitelist = array();
$whitelist[] = "internal1.se";
$whitelist[] = "internal2.no";
$whitelist[] = "internal3.com";
// and so on...

$string = '<a href="http://proxy.org/browse.php?u=http%3A%2F%2Fexternal1.com&b=0">External link 1</a><br>';
$string .=  '<a href="http://proxy.org/browse.php?u=http%3A%2F%2Finternal1.se&b=0">Internal link 1</a><br>';
$string .=  '<a href="http://proxy.org/browse.php?u=http%3A%2F%2Finternal3.com&b=0">Internal link 2</a><br>';
$string .=  '<a href="http://proxy.org/browse.php?u=http%3A%2F%2Fexternal2.no&b=0">External link 2</a><br>';

//Assuming the URL always is inside '' or "" you can use this pattern:
$pattern = '#(https?://proxy\.org/browse\.php\?u=(https?[^&|\"|\']*)(&?[^&|\"|\']*))#i';

$string = preg_replace_callback($pattern, "my_callback", $string);

//I had only PHP 5.2 on my server, so I decided to use a callback function. 
function my_callback($match) {
    global $whitelist;
    // set return bypass proxy URL
    $returnstring = urldecode($match[2]);

    foreach ($whitelist as $white) {
        // check if URL matches whitelist
        if (stripos($match[2], $white) > 0) {
            $returnstring = $match[0];
            break; } }
    return $returnstring;
}

echo "NEW STRING[:\n" . $string . "\n]\n";