Getting just the Location from Header of cURL Request - php

Question

I'm trying to retrieve the location URL of an image after a redirect, but I can't seem to get it to work. I've never used cURL before, but from the research I've done it looks like I need it to get an image from Facebook. Here's my code so far:
function getImage($url) {
$ch = curl_init();
// Only calling the head
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_HEADER, true); // header will be at output
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, 'HEAD'); // HTTP request is 'HEAD'
$content = curl_exec($ch);
curl_close($ch);
return $content;
}
$image = explode("Location: ", getImage("http://graph.facebook.com/553451657/picture?type=large"));
print_r($image);
But my response is:
HTTP/1.1 302 Found Access-Control-Allow-Origin: * Cache-Control: private, no-cache, no-store, must-revalidate Content-Type: image/jpeg Expires: Sat, 01 Jan 2000 00:00:00 GMT Location: http://profile.ak.fbcdn.net/hprofile-ak-snc4/161877_553451657_798840908_n.jpg Pragma: no-cache X-FB-Rev: 590433 X-FB-Debug: WH1uJvIjUqiLT8ezVPdude8VKYnXjAHRlFaP8gqF9fI= Date: Fri, 13 Jul 2012 17:56:09 GMT Connection: keep-alive Content-Length: 0 Array ( [0] => 1 )
How do I JUST get the Location part ("http://profile.ak.fbcdn.net/hprofile-ak-snc4/161877_553451657_798840908_n.jpg")?

Answer 1

You can do a function on the headers:
$headers = [];
curl_setopt($curl, CURLOPT_HEADERFUNCTION, function ($ch, $header) use (&$headers) {
$matches = array();
if ( preg_match('/^([^:]+)\s*:\s*([^\x0D\x0A]*)\x0D?\x0A?$/', $header, $matches) )
{
$headers[$matches[1]][] = $matches[2];
}
return strlen($header);
});
(seen here)
Then you get it stored in $headers["Location"][0].
I am also, like you, trying to get the fb page image this way, it seems no PHP SDK, App priviledges or access_token is needed for that, but there might be some limitations (anybody knows?)

Answer 2

How do I JUST get the Location part
Getting that Location header is not you’re primary goal, right? You want to get the image from the address that’s being redirected to, correct?
So just set the option CURLOPT_FOLLOWLOCATION, and cURL will follow that redirect automatically and fetch the real image for you.