Laravel 5.1 Call PHP file on Javascript string

How to call some PHP file in Laravel 5.1.

I have to see of that PHP file echo.

Here is the Javascript codes

<script>
$(document).ready(function(){
    $('#example').DataTable({
        "processing": true,
        "serverSide": true,
        "ajax": 'processing.php'
    });
});
</script>

via Chebli Mohamed