code: public function push(string $event, $event_args = null) : EventChannelInterface
      {
          try{
              $this->channel->push($event, $event_args);
          }
          catch(EventSourceIsNotPushableException $e)
          {
              throw new EventStreamException('Event is not pushable.');
          }
          return $this;
      }
docs: Push an event to channel
  
  @param string $event
  @param null $event_args
  
  @return EventChannelInterface
  
  @throws EventStreamException