code: func (m *MockEventService) RegisterChaincodeEvent(ccID, eventFilter string) (fab.Registration, <-chan *fab.CCEvent, error) {
  	eventCh := make(chan *fab.CCEvent)
  	reg := &dispatcher.ChaincodeReg{
  		Eventch:     eventCh,
  		ChaincodeID: ccID,
  		EventFilter: eventFilter,
  	}
  	return reg, eventCh, nil
  }
docs: // RegisterChaincodeEvent registers for chaincode events.