nexo Retailer

Event Notifications

Event Notifications are sent from the terminal in a few special occasions

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Event notifications are sent from the terminal to the POS to inform the POS about different things. They do not require a response message and it is not a must to implement any handeling of them, but it may be helpful and make a nice solution. They will only appear if the implementation has a listener for terminal requests.

The most commonly used event notifications are those informing about parameter updates.

 <MessageHeader MessageClass="Event" MessageCategory="Event" MessageType="Notification" ServiceID="20" SaleID="1" POIID="A-POIID"/>
 <EventNotification TimeStamp="2023-10-06T07:24:14.473+02:00" EventToNotify="SaleAdmin" MaintenanceRequiredFlag="true">
  <EventDetails>Maintenance Required</EventDetails>
Name Lev Attribute Description
EventNotification 1 TimeStamp Local time when the event occurred.
    EventToNotify The essential attribute informing what it is about. Enumeration: SaleAdmin, BeginMaintenance, EndMaintenance, Reject, CardInserted, CardRemoved.
    MaintenanceRequired true or false. If true, there are updates that will be implemented at next logout if maintenance allowed is set.
EventDetails 2   Informational text about the event. Note! not always present.
RejectedMessage 2   If EventToNotify is Reject.

Example flow

participant POS
participant Terminal
Terminal->>POS: EventNotification SaleAdmin
Note over Terminal: MaintenanceRequired="true"
POS->>Terminal: LogoutRequest
Note over POS: MaintenanceAllowed="true"
Terminal->>POS: LogoutResponse Success
Terminal->>POS: EventNotification BeginMaintenance
Note left of Terminal: Update from TMS is implemented
Terminal->>POS: EventNotification EndMaintenence
POS->>Terminal: LoginRequest