如何从URL中找出实际的URL，重定向到另一个URL

Question

From an RSS feed of a news website, I get a list of articles published. As this website is using feedburner for RSS, each article has another URL which redirects to the actual URL of an article. I need to get the actual URL and using this URL I'll get the total FB shares and tweets of this article.

Sample RSS feed: http://feeds.hindustantimes.com/HT-HomePage-TopStories. This feed has an article - http://feeds.hindustantimes.com/~r/HT-HomePage-TopStories/~3/Go3sAI0Bv94/story01.htm which redirects to actual URL - http://www.hindustantimes.com/india-news/mumbai/complaint-against-fake-twitter-accnts-of-party-chief-s-kids/article1-1287174.aspx.

Is there any way PHP I can get the actual URL?

Answer 1

You can use either get_headers, or curl with the flag CURLOPT_FOLLOWLOCATION set in order to grab redirects. The following snippet uses get_headers.

function get_redirected_url($url)
{
    $redirected_url = false;

    // First check response headers
    $headers = get_headers($url);

    // Test for 301 or 302
    if(preg_match('/^HTTP\/\d\.\d\s+(301|302)/',$headers[0]))
    {
        foreach($headers as $value)
        {
            if(substr(strtolower($value), 0, 9) == "location:")
            {
                $redirected_url = trim(substr($value, 9, strlen($value)));
            }
        }
    }

    return ($redirected_url) ? $redirected_url : $url;
}