This symbol shall be used to install a listener for only monitoring 'error'
events. Listeners installed using this symbol are called before the regular
'error' listeners are called.
Installing a listener using this symbol does not change the behavior once an
'error' event is emitted, therefore the process will still crash if no
regular 'error' listener is installed.
true if the underlying channel has been closed or aborted...
number of subscriptions ever created since this object is live
number of monitored items
number of active subscriptions
close a ServerSession, this will also delete the subscriptions if the flag is set.
Spec extract:
If a Client invokes the CloseSession Service then all Subscriptions associated with the Session are also deleted if the deleteSubscriptions flag is set to TRUE. If a Server terminates a Session for any other reason, Subscriptions associated with the Session, are not deleted. Each Subscription has its own lifetime to protect against data loss in the case of a Session termination. In these cases, the Subscription can be reassigned to another Client before its lifetime expires.
: should we delete subscription ?
returns rootFolder.objects.server.serverDiagnostics.sessionsDiagnosticsSummary.sessionDiagnosticsArray
returns rootFolder.objects.server.serverDiagnostics.sessionsDiagnosticsSummary.sessionSecurityDiagnosticsArray
retrieve an existing subscription by subscriptionId
Generated using TypeDoc
A Server session object.
from OPCUA Spec 1.02:
Sessions are created to be independent of the underlying communications connection. Therefore, if a communication connection fails, the Session is not immediately affected. The exact mechanism to recover from an underlying communication connection error depends on the SecureChannel mapping as described in Part 6.
Sessions are terminated by the Server automatically if the Client fails to issue a Service request on the Session within the timeout period negotiated by the Server in the CreateSession Service response. This protects the Server against Client failures and against situations where a failed underlying connection cannot be re-established.
Clients shall be prepared to submit requests in a timely manner to prevent the Session from closing automatically.
Clients may explicitly terminate Sessions using the CloseSession Service.
When a Session is terminated, all outstanding requests on the Session are aborted and BadSessionClosed StatusCodes are returned to the Client. In addition, the Server deletes the entry for the Client from its SessionDiagnosticsArray Variable and notifies any other Clients who were subscribed to this entry.