//Callback for MQTT connection.
async void IServiceCallback.MQTTConnect(string brokerIP)
{
await mqttClientSemaphore.WaitAsync();
try
{
managedMqtt = ServiceLogic.CreateManagedClient();
await ServiceLogic.ManagedMqttConnectWebSocket(managedMqtt, brokerIP);
}
finally
{
mqttClientSemaphore.Release();
}
}
protected override void OnStart(string[] args)
{
try
{
createDirectories();
//Set the static callback reference and creates interface for WinForms by hosting a WCF Service.
Host.Current = this;
StartBroker();
// Log an event to indicate successful start.
EventLog.WriteEntry("Successful start.", EventLogEntryType.Information);
//Initialize MQTT Client.
managedMqtt = ServiceLogic.CreateManagedClient();
//MQTT Broker connection
string brokerIP = "dev-harmony-01.southeastasia.cloudapp.azure.com:8080/mqtt";
MQTTConnectClient(managedMqtt, brokerIP);
//Initialize OPC Application Instance
application = new ApplicationInstance
{
ApplicationName = "MQTT-OPC Broker",
ApplicationType = ApplicationType.ClientAndServer,
ConfigSectionName = "Opc.Ua.SampleClient"
};
//load the application configuration.
application.LoadApplicationConfiguration(false).Wait();
// check the application certificate.
application.CheckApplicationInstanceCertificate(false, 0).Wait();
m_configuration = app_configuration = application.ApplicationConfiguration;
// get list of cached endpoints.
m_endpoints = m_configuration.LoadCachedEndpoints(true);
m_endpoints.DiscoveryUrls = app_configuration.ClientConfiguration.WellKnownDiscoveryUrls;
if (!app_configuration.SecurityConfiguration.AutoAcceptUntrustedCertificates)
{
app_configuration.CertificateValidator.CertificateValidation += new CertificateValidationEventHandler(CertificateValidator_CertificateValidation);
}
//If there was a pre-exising session before, attempt reconnection.
foreach (string sessionFile in Directory.GetFiles(sessionsFolder, "*.json"))
{
String[] sessions = File.ReadAllLines(sessionFile);
foreach (string retainedEndpoint in sessions)
{
if (retainedEndpoint != "")
{
try
{
OPCConnect(application, retainedEndpoint);
sessionEndpoint = retainedEndpoint;
break;
}
catch
{
//Ignore exception as server may not be up.
}
break;
}
}
String readSession = File.ReadAllText(sessionFile);
}
serviceCheck = true;
//Use timer callback to monitor and publish subscriptions.
publishTimer = new System.Threading.Timer(x => OPCPublish(m_session), null, 5000, 1000);
}
catch (Exception ex)
{
EventLog.WriteEntry(ex.Message, EventLogEntryType.Error);
}
}
