private async Task CreateOpcuaSessionAsync()
{
try
{
if (_sessionClient == null)
{
_sessionClient = new OpcUaClientSession();
}
await _sessionClient.CreateSessionAsync(_config);
_monitoredItemsHandler = new MonitoredItemsHandler(_sessionClient, _appSettings);
StartConnectionCheckTimer();
SysLog.Info($"Connected to server: { _config.Endpoint.EndpointUrl} .");
}
catch (Exception)
{
var message = "Failed to connect to server, Please check opcua server is running";
SysLog.Error(message);
OnCheckConnectionTimerOnElapsed(this, new EventArgs() as ElapsedEventArgs);
//throw new Exception(message);
}
}
public Subscription CreateSubscription(OpcUaClientSession session)
{
SysLog.Info("Creating new subscription ...");
if (!session.IsConnected)
{
SysLog.Error("Could not create subscription because opcua client session is null. Please check the OPCUA Server status");
return(null);
}
IsSubscriptionTypePublishing = true;
_subscription = new Subscription
{
DisplayName = Constants.DefaultSubscriptionName,
PublishingInterval = _appSettings.SubscriptionPublishIntervalMs,
TimestampsToReturn = TimestampsToReturn.Both,
Priority = 0, //byte data type range from 0 to 255,
KeepAliveCount = _appSettings.SubscriptionKeepAliveCount,
LifetimeCount = _appSettings.SubscriptionLifetimeCount,
MaxNotificationsPerPublish = 100000
};
session.AddSubscription(_subscription);
_subscription.Create();
_subscription.SetPublishingMode(IsSubscriptionTypePublishing);
if (IsSubscriptionTypePublishing)
{
_subscription.PublishStatusChanged += OnPublishStatusChanged;
}
else
{
SysLog.Info(GetDisplayString(_subscription));
}
SysLog.Info("Created new subscription.");
return(_subscription);
}
public MonitoredItemsHandler(OpcUaClientSession session, AppSettings appSettings)
{
_session = session;
_appSettings = appSettings;
_notLocatedFileName = _appSettings.PrefixNoLocatedSensorsFileName + $"{DateTime.Now:yyyy_MM_dd_HH_mm_ss}" + ".csv";
}