How to get all query string from Request class in laravel 5.0

In my project I am using payment gateway and Omnipay want to know if its redirecting from "back to webiste button" or by clicking on cancel button.

Its redirecting to a page called complete even when its redirected.

I have checked the code and there I see:

$payerId = Request::query('PayerID');
$token = Request::query('token');

So now I want to get all query value like payerID,etc. to check if something indicating weather its redirect or successfully completed.

I know how to make payment by this gateway but any how in this project i am getting some trouble.

Thanks.

Personally i used this:

public function foo(Request $request)
    {
        $all = $request->all(); // there you have an array with all input submitted
        //do something with input
        return redirect()->action('HomeController@index');
    }