Using cURL to findout where website redirects? - php

Question

I'm trying to get server redirect url. I have tried
function http_head_curl($url,$timeout=10)
{
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_TIMEOUT, $timeout); // in seconds
curl_setopt($ch, CURLOPT_HEADER, 1);
curl_setopt($ch, CURLOPT_NOBODY, 1);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
$res = curl_exec($ch);
if ($res === false) {
throw new RuntimeException("cURL exception: ".curl_errno($ch).": ".curl_error($ch));
}
return trim($res);
}
echo http_head_curl("http://www.site.com",$timeout=10);
Result is;
HTTP/1.1 301 Moved Permanently Date: Sun, 12 May 2013 23:34:22 GMT
Server: LiteSpeed Connection: close X-Powered-By: PHP/5.3.23
Set-Cookie: PHPSESSID=0d4b28dd02bd3d8413c92f71253e8b31; path=/;
HttpOnly X-Pingback: http://site.com/xmlrpc.php Content-Type:
text/html; charset=UTF-8 Location: http://site.com/ HTTP/1.1 200 OK
Date: Sun, 12 May 2013 23:34:23 GMT Server: LiteSpeed Connection:
close X-Powered-By: PHP/5.3.23 Set-Cookie:
PHPSESSID=630ed27f107c07d25ee6dbfcb02e8dec; path=/; HttpOnly
X-Pingback: http://site.com/xmlrpc.php Content-Type: text/html;
charset=UTF-8
It shows almost all header information, but not showing where it redirects. How do I get the redirected page url ?

Answer 1

It's the Location header.
$headers = array();
$lines = explode("\n", http_head_curl('http://www.site.com', $timeout = 10));
list($protocol, $statusCode, $statusMsg) = explode(' ', array_shift($lines), 3);
foreach($lines as $line){
$line = explode(':', $line, 2);
$headers[trim($line[0])] = isset($line[1]) ? trim($line[1]) : '';
}
// 3xx = redirect
if(floor($statusCode / 100) === 3)
print $headers['Location'];

Answer 2

$response = curl_exec($ch);
$info = curl_getinfo($ch);
$response_header = substr($response, 0, $info['header_size']);
$response_header = parseHeaders($response_header, 'Status');
$content = substr(response, $info['header_size']);
$url_redirect = (isset($response_header['Location'])) ? $response_header['Location'] : null;
var_dump($url_redirect);
/*
* or you can use http://php.net/http-parse-headers,
* but then need to install http://php.net/manual/en/book.http.php
*/
function parseHeaders($headers, $request_line)
{
$results = array();
$lines = array_filter(explode("\r\n", $headers));
foreach ($lines as $line) {
$name_value = explode(':', $line, 2);
if (isset($name_value[1])) {
$name = $name_value[0];
$value = $name_value[1];
} else {
$name = $request_line;
$value = $name_value[0];
}
$results[$name] = trim($value);
}
return $results;
}

Answer 3

After your CURL request is done, use curl_getinfo with the CURLINFO_EFFECTIVE_URL option. Done.
Compared to the other (complicated) answers, this will provide you the full URL that your request "ended up on".