Facebook Application Tab -> External Linking with PHP

Question

I currently have an Application on the Facebook Tab, and am wondering if there is a way for me to deep link into an item on that app tab. Example:

User is in the applic

Answer 1

Here's how we deep link to subpages within our app's Page Tab.

When your application lives inside a Page Tab, Facebook will strip out all GET params except for app_data. It passes app_data inside the signed_request parameter of the POST data.

More info in the docs: https://developers.facebook.com/docs/authentication/signed_request/

So when we build links to subpages, it will look something like

http://www.facebook.com/myfanpage?sk=app_XXXXXX&app_data=%2Fmainpage%2Fsubpage

Then, in our index page code, we check for the app_data param. If it exists, then a simple 302 redirect does the trick.

$request = parse_signed_request($_POST['signed_request']);
if ($request['app_data'])
{
    header('HTTP/1.1 302 Found');
    header('Location: {$request['app_data']}');
    exit;
}

Note: you can pass more than 1 param inside of app_data using a URL-encoded, JSON-array or something like that.