3.11 Cancel Reservation

The CancelReservation message in OCPP 1.6J is sent by the central system to cancel a reservation at the charge point using a specific ReservationId. It ensures that the reserved connector is freed up, making it available for other users. The charge point responds to acknowledge the cancellation.


API Syntax	Description	Input Params	Return Value
SetCancelReservationStatus	Sets the status of the CancelReservation response. This function updates the response status based on the outcome of the cancellation request.	CANCEL_RESERVATION_STATUS_T Status	void

Example:

  if ((CANCEL_RESERVATION_STATUS_T)responsecode == CANCEL_RESERVATION_MISSING_RESERVATION_ID)
  {
    LogDebug("APP_LOG", " CancelReservation request missing Reservation Id\n");
    SetCancelReservationStatus(CANCEL_RESERVATION_REJECTED); /* Set for testing */
    (void)SendCancelReservationResponse();
  }


API Syntax	Description	Input Params	Return Value
CancelReservationInit	Initializes the CancelReservation response structure with default values.	void	void

Example:

void OCPPMessagesInit(void)
{
    DataTransferInit();
    ResetInit();
    MeterValueStructInit();
    SetLocalListVersionNumber(DEFAULT_SEND_LOCAL_LIST_VERSION);   
    SetChargePointConnectorId(CHARGEPOINT_DEFAULT_CONTROLLER);
    SetChargePointError(NOERROR);
    SetChargePointStatus(AVAILABLE);
    SetAuthorizeStatus(AUTHORIZE_INVALID);
    SetRemoteStartTransactionStatus(REMOTE_START_STOP_REJECTED);
    SetOCPPWebsocketOnlineMode();
    UnlockConnectorInit();
    ReserveNowInit();
    ChangeAvailabilityInit();
    ClearCacheInit();
    ChangeConfigurationInit();
    CancelReservationInit();
    GetAllIDsFromDB();
    CheckAndStartClockAlignedMeterValueTimer();
}


API Syntax	Description	Input Params	Return Value
GetCancelReservationParams	Retrieves the reservation ID from the CancelReservation request. The reservation ID is provided through the function's parameter.	uint16_t *reservationId	void

Example:

if (responsecode == CANCEL_RESERVATION_MISSING_RESERVATION_ID)
  {
    LogDebug("APP_LOG", " CancelReservation request missing Reservation Id\n");
    SetCancelReservationStatus(CANCEL_RESERVATION_REJECTED); /* Set for testing */
    SendCancelReservationResponse();
  }
  else
  {
    uint16_t reservationId;
    uint8_t connectorId = GetChargePointConnectorId();
    GetCancelReservationParams(&reservationId);
    GetReserveNowParams(&params);
    LogDebug("APP_LOG", " CancelReservationId:%d  ReserveNowRservationId: %d\n", reservationId, params.reservationId);
    if (reservationId == params.reservationId)
    {
      SetCancelReservationStatus(CANCEL_RESERVATION_ACCEPTED); /* Set for testing */
      SendCancelReservationResponse();

      UpdateAndSendStatusNotification(AVAILABLE, NOERROR, connectorId);
    }
    else
    {
      SetCancelReservationStatus(CANCEL_RESERVATION_REJECTED); /* Set for testing */
      SendCancelReservationResponse();
    }
  }


Syntax	Description	Constants/Members
CANCELRESERVATION_RESPONSE_T	This structure represents the response to a CancelReservation request. It includes the status of the cancellation request.	CANCEL_RESERVATION_STATUS_T status;
RX_CANCELRESERVATION_T	This structure represents a CancelReservation request. It includes fields for the unique identifier of the request and the reservation ID to be cancelled.	char uuid[]; uint16_t reservationId;
CANCEL_RESERVATION_STATUS_T	This enumeration defines the possible statuses for a CancelReservation response. The status indicates the outcome of the reservation cancellation process.	CANCEL_RESERVATION_ACCEPTED CANCEL_RESERVATION_REJECTED CANCEL_RESERVATION_MISSING_RESERVATION_ID