Header location infinite redirect Loop

Question

I have this huge issue that I have no idea how to fix. I have a script that redirects to a url.

So far I have:

//do some mysql
$geo_included = true; //trying to fix infinite redirect loop.
if($geo_included === true){
    header('Location: '.$url["url"]); //this is causing the issue with redirect loop
}

$url["url"] for example is: www.google.com

But when I go to that PHP file it will redirect to:

www.sitename.com/www.google.com

and say there is an infinite redirect loop. Note: the above header location script is not in a while/for/foreach loop.

Here is my .htaccess for the / directory

RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ index.php?group=$1 [L]

Any ideas?

possible duplicate of [Absolute vs relative URLs](http://stackoverflow.com/questions/2005079/absolute-vs-relative-urls) — Anonymous, Jun 10 '14 at 21:00

Mr. Llama · Accepted Answer · 2014-06-10T21:20:12.963

7

You need to include the fully qualified domain name with scheme, otherwise it's interpreted as being in the current domain:

header('Location: google.com'); // Redirects to http://cursite.com/www.google.com
header('Location: http://google.com'); // Redirects as expected

If you are unsure if your URL includes a scheme, check the results from parse_url.

$url_scheme = parse_url($url, PHP_URL_SCHEME);
// www.google.com -> NULL
// http://google.com -> string(4) "http"
// ftp://site.com -> string(3) "ftp"

edited Jun 10 '14 at 21:20

answered Jun 10 '14 at 21:00

Mr. Llama

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All good, but how can the original poster ensure that `http://` is prepended if it doesn’t already exist? Check my answer out to see how I am handling that. – Giacomo1968 Jun 10 '14 at 21:10
1

@JakeGould - Edited to include `parse_url` to check the URL. – Mr. Llama Jun 10 '14 at 21:20

Giacomo1968 · Answer 2 · 2014-06-10T21:10:04.117

The quick proof-of-concept solution here is to prepend http:// to the URL like this:

$geo_included = true;

if ($geo_included) {
    header('Location: http://' . $url["url"]);
}

I say “proof of concept” because what you should do is ensure the $url["url"] always has a protocol attached to it. Either before it gets into the database, or in this code snippet by doing a check on the $url["url"] value to see of it has http:// or https:// and if it doesn’t, prepend it. And here is a quickly thrown together example of what I mean which should work:

$geo_included = true;

if ($geo_included) {
    $protocol = (!preg_match("~^(?:ht)tps?://~i", $url["url"])) ? 'http://' : null;
    header('Location: ' $protocol . $url["url"]);
}

The line with $protocol = … does the check I explained before. The default is to add http:// if it’s not there.

Also, note I removed === true since the if ($geo_included) { is basically the same thing.

Header location infinite redirect Loop

2 Answers2