php - Save facebook profile image using cURL

Question

I'm trying to save a users profile image on facebook using CURL. When I use the code below, I save a jpeg image but it has zero bytes in it. But if I exchange the url value to https://fbcdn-profile-a.akamaihd.net/hprofile-ak-snc4/211398_812269356_2295463_n.jpg, which is where http://graph.facebook.com/' . $user_id . '/picture?type=large redirects the browser, the image is saved without a problem. What am I doing wrong here?

<?php

$url = 'http://graph.facebook.com/' . $user_id . '/picture?type=large';


$file_handler = fopen('pic_facebook.jpg', 'w');
$curl = curl_init($url);
curl_setopt($curl, CURLOPT_FILE, $file_handler);
curl_setopt($curl, CURLOPT_HEADER, false);

curl_exec($curl);

curl_close($curl);
fclose($file_handler);

?>

Answer 1

There is a redirect, so you have to add this option for curl

// safemode if off:
curl_setopt($curl, CURLOPT_FOLLOWLOCATION, true);

but if you have safemode if on, then:

// safemode if on:
<?php
function curl_redir_exec($ch)
    {
        static $curl_loops = 0;
        static $curl_max_loops = 20;
        if ($curl_loops++ >= $curl_max_loops)
        {
            $curl_loops = 0;
            return FALSE;
        }
        curl_setopt($ch, CURLOPT_HEADER, true);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
        $data = curl_exec($ch);
        @list($header, $data) = @explode("

", $data, 2);
        $http_code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
        if ($http_code == 301 || $http_code == 302)
        {
            $matches = array();
            preg_match('/Location:(.*?)
/', $header, $matches);
            $url = @parse_url(trim(array_pop($matches)));
            if (!$url)
            {
                //couldn't process the url to redirect to
                $curl_loops = 0;
                return $data;
            }
            $last_url = parse_url(curl_getinfo($ch, CURLINFO_EFFECTIVE_URL));
            if (!$url['scheme'])
                $url['scheme'] = $last_url['scheme'];
            if (!$url['host'])
                $url['host'] = $last_url['host'];
            if (!$url['path'])
                $url['path'] = $last_url['path'];
            $new_url = $url['scheme'] . '://' . $url['host'] . $url['path'] . (@$url['query']?'?'.$url['query']:'');
            return $new_url;
        } else {
            $curl_loops=0;
            return $data;
        }
    }

    function get_right_url($url) {
        $curl = curl_init($url);
        curl_setopt($curl, CURLOPT_HEADER, false);
        curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
        return curl_redir_exec($curl);
    }


    $url = 'http://graph.facebook.com/' . $user_id . '/picture?type=large';

    $file_handler = fopen('pic_facebook.jpg', 'w');
    $curl = curl_init(get_right_url($url));
    curl_setopt($curl, CURLOPT_FILE, $file_handler);
    curl_setopt($curl, CURLOPT_HEADER, false);
    curl_exec($curl);

    curl_close($curl);
    fclose($file_handler);