public async Task TransferSubscription()
{
var channel1 = new ClientSessionChannel(
localDescription,
certificateStore,
new UserNameIdentity("root", "secret"),
EndpointUrl,
loggerFactory: loggerFactory);
await channel1.OpenAsync();
logger.LogInformation($"Opened session with endpoint '{channel1.RemoteEndpoint.EndpointUrl}'.");
logger.LogInformation($"SecurityPolicy: '{channel1.RemoteEndpoint.SecurityPolicyUri}'.");
logger.LogInformation($"SecurityMode: '{channel1.RemoteEndpoint.SecurityMode}'.");
logger.LogInformation($"Activated session '{channel1.SessionId}'.");
// create the keep alive subscription.
var subscriptionRequest = new CreateSubscriptionRequest
{
RequestedPublishingInterval = 1000f,
RequestedMaxKeepAliveCount = 30,
RequestedLifetimeCount = 30 * 3,
PublishingEnabled = true,
};
var subscriptionResponse = await channel1.CreateSubscriptionAsync(subscriptionRequest).ConfigureAwait(false);
var id = subscriptionResponse.SubscriptionId;
void onPublish(PublishResponse pr)
{
// loop thru all the data change notifications and log them.
var dcns = pr.NotificationMessage.NotificationData.OfType <DataChangeNotification>();
foreach (var dcn in dcns)
{
foreach (var min in dcn.MonitoredItems)
{
logger.LogInformation($"sub: {pr.SubscriptionId}; handle: {min.ClientHandle}; value: {min.Value}");
}
}
}
void onPublishError(Exception ex)
{
logger.LogInformation("Exception in publish response handler: {0}", ex.GetBaseException().Message);
}
var token = channel1
.Where(pr => pr.SubscriptionId == id)
.Subscribe(onPublish, onPublishError);
var itemsRequest = new CreateMonitoredItemsRequest
{
SubscriptionId = id,
ItemsToCreate = new MonitoredItemCreateRequest[]
{
new MonitoredItemCreateRequest {
ItemToMonitor = new ReadValueId {
NodeId = NodeId.Parse("i=2258"), AttributeId = AttributeIds.Value
}, MonitoringMode = MonitoringMode.Reporting, RequestedParameters = new MonitoringParameters {
ClientHandle = 12345, SamplingInterval = -1, QueueSize = 0, DiscardOldest = true
}
}
},
};
var itemsResponse = await channel1.CreateMonitoredItemsAsync(itemsRequest);
await Task.Delay(3000);
var channel2 = new ClientSessionChannel(
localDescription,
certificateStore,
new UserNameIdentity("root", "secret"),
EndpointUrl);
await channel2.OpenAsync();
var token2 = channel2
.Where(pr => pr.SubscriptionId == id)
.Subscribe(onPublish, onPublishError);
var transferRequest = new TransferSubscriptionsRequest
{
SubscriptionIds = new[] { id },
SendInitialValues = true
};
var transferResult = await channel2.TransferSubscriptionsAsync(transferRequest);
StatusCode.IsGood(transferResult.Results[0].StatusCode)
.Should().BeTrue();
logger.LogInformation($"Transfered subscriptions to new client.");
await Task.Delay(3000);
logger.LogInformation($"Closing session '{channel1.SessionId}'.");
await channel1.CloseAsync();
logger.LogInformation($"Closing session '{channel2.SessionId}'.");
await channel2.CloseAsync();
}
