public function process()
 {
     parent::process();
     if (!empty($this->stream_source)) {
         $buffer = $this->stream_source->buffering();
         if (!empty($buffer)) {
             $this->broadcast($buffer);
         }
     }
 }
 public function start()
 {
     parent::start();
     echo 'Chat Server started!' . PHP_EOL;
 }