Tracing HTTP Redirects

Example to trace through HTTP redirects.

Download Chilkat HTTP ActiveX

<?php

$http = new COM("Chilkat.Http");

//  Any string unlocks the component for the 1st 30-days.
$success = $http->UnlockComponent('Anything for 30-day trial');
if ($success != true) {
    print $http->lastErrorText() . "\n";
    exit;
}

$url = 'http://www.some-site-with-a-redirect.com/';

//  The FollowRedirects property controls whether redirects
//  are automatically followed.  The default behavior is to
//  automatically follow redirects.

//  Explicitly set FollowRedirects so that redirects are NOT automatically taken:
$http->FollowRedirects = false;

//  Send the HTTP GET and return the content in a string.
$html = $http->quickGetStr($url);
if (is_null($html)) {
    print $http->lastErrorText() . "\n";
}

$status = $http->LastStatus;
print 'HTTP Response Status: ' . $status . "\n";

//  The FinalRedirectUrl property will contain the redirect URL
//  If FollowRedirects was equal to 1, then all of the
//  intermediate redirects (if any) would be followed until
//  there were no more redirects.  However, because
//  FollowRedirects is not 1, FinalRedirectUrl contains
//  the next redirect URL.
print 'Redirect URL: ' . $http->finalRedirectUrl() . "\n";

$loopCount = 0;

while (($status == 302)) {
    $url = $http->finalRedirectUrl();
    $html = $http->quickGetStr($url);
    if (is_null($html)) {
        print $http->lastErrorText() . "\n";
        break;
    }

    $status = $http->LastStatus;
    print 'Redirect URL: ' . $http->finalRedirectUrl() . "\n";

    //  You may wish to check that if FinalRedirectUrl
    //  equals the URL just retrieved.  If so, then break out of the
    //  loop.  (This check is omitted in this example.)

    //  Instead, this example will prevent infinite loops by
    //  keeping a loopCount and only allows following a max
    //  of 10 redirects:
    $loopCount = $loopCount + 1;
    if ($loopCount > 10) {
        break;
    }

}

?>