How can I determine if a URL redirects in PHP?

Question

I saw someone ask a question about detecting if a URL redirects from groovy and perl but couldn't find anything on PHP.

Anyone know of somewhere I could find that code that does this?

G-Man

Answer 1

$ch = curl_init('http://www.yahoo.com/');
curl_exec($ch);
$code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
if (($code == 301) || ($code == 302)) {
  //This was a redirect
}

Answer 2

Actually, I found this works best:

    function GetURL($URL)
    {
            $ch = curl_init($URL);

            curl_setopt($ch,CURLOPT_FOLLOWLOCATION,true);


            curl_setopt($ch,CURLOPT_RETURNTRANSFER,true);

            curl_exec($ch);

            $code = curl_getinfo($ch, CURLINFO_EFFECTIVE_URL);

            curl_close($ch);

            return $code;
    }

Answer 3

Do remember that none of the answers that are usually given for this question take into account redirection caused by javascript encoded within the returned document (or I think a meta-refresh tag in the HTML.) So it's possible that no matter what you will miss certain kinds of "redirects" when testing using this sort of code.

Unfortunately the only way around this is to have an actual web browser hit the web page, and have the web browser modified in such a manner which it reports javascript and meta-refresh redirections.

Cheers!