OnConnectionEvent
This event indicates that the NATS server connection status has changed. The CONNECTION_EVENT property indicates the event.
NB: no event is received if the connection is closed voluntarily.
OnMessage
This event is triggered when a message is received by a NATS subscriber. MESSAGE_SUBJECT, MESSAGE_DATA, REPLY_TO, HEADER_PRESENT, JETSTREAM and MESSAGE_SID properties are available in this event.
OnSubscriberError
This event is triggered when a NATS subscriber stops in error.
NB: if there are lost connection issues, the subscribers are suspended and do not emit errors.