Interaction Diagram: Subscribe Associations Discovery
For subscribing to asynchronously receive notifications about the current set of
associations fitting a VE Specification and a VE Service Specification, an IoT
Service Client synchronously calls the VE Resolution, using the
subscribeAssociationDiscovery operation with the VE Specification specifying
the Virtual Entities of interest, the VE Service Specification identifying the
services associated to the Virtual Entities that are of interest and the notification
callback, to which notifications are to be sent, as parameters. The notification
callback identifies the endpoint on the IoT Service Client side that implements
the notifyAssociationDiscovery operation. The VE Resolution returns the
subscription identifier that can be used to map an incoming notification to the
subscription it belongs to.
Subsequently, the VE Resolution will call the notifyAssociationDiscovery
operation of the IoT Service client, providing the associations and the
subscription ID as parameters. A notification will be sent whenever a previously
provided association changes or is deleted. A notification will also be sent if a
new association fitting the given VE Specification and VE Service Specification
becomes available.
When the IoT Service Client is no longer interested in receiving notifications
pertaining to the subscription, it will call the unsubscribeAssociationDiscovery
operation of the VE Resolution using the subscription identifier as parameter.
As a result, the VE Resolution will stop sending notifications pertaining to the
identified subscription.