public function check(Event $event)
 {
     list($algorithm, $signature) = explode('=', $event->getSignature());
     $payLoadHash = hash_hmac($algorithm, $event->getContent(), $this->secret);
     if ($payLoadHash === $signature) {
         return true;
     } else {
         return false;
     }
 }
 public function it_will_return_false_on_check_fail(Event $event)
 {
     $event->getSignature()->willReturn('sha1=abc123');
     $event->getContent()->willReturn('{}');
     $this->check($event)->shouldReturn(false);
 }