// This example shows how to connect to the data source only when the producer is online.
//
// You can use any Sparkplug application, including our SparkplugCmd utility and the SparkplugApplicationConsoleDemo
// program, to subscribe to the edge node data.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-ConnectivityStudio/Latest/examples.html .
// Sparkplug examples in C# on GitHub: https://github.com/OPCLabs/Examples-ConnectivityStudio-CSharp .
// Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
// a commercial license in order to use Online Forums, and we reply to every post.
using System;
using OpcLabs.EasySparkplug;
namespace SparkplugDocExamples.EdgeNode._EasySparkplugEdgeNode
{
class DataSourceConnectionMode
{
static public void Main1()
{
// Note that the default port for the "mqtt" scheme is 1883.
var hostDescriptor = new SparkplugHostDescriptor("mqtt://localhost");
// Instantiate the edge node object.
var edgeNode = new EasySparkplugEdgeNode(hostDescriptor, "easyGroup", "easySparkplugDemo");
// Configure the edge node to connect to the data source only when the producer is online. You can test it out
// e.g. by stopping or disconnecting from the MQTT broker.
//
// You can compare the output of this example with and without the statement below. With the statement, the
// Poll event will not be raised unless the producer is online. Without the statement, the Poll event will
// always be raised while the edge node is started, regardless of the MQTT broker connection state.
edgeNode.DataSourceConnectionMode = SparkplugDataSourceConnectionMode.WhenProducerOnline;
// Hook the SystemConnectionStateChanged event to handle system connection state changes.
edgeNode.SystemConnectionStateChanged += (sender, eventArgs) =>
{
// Display the new connection state (such as when the connection to the broker succeeds or fails).
Console.WriteLine($"{nameof(EasySparkplugEdgeNode.SystemConnectionStateChanged)}: {eventArgs}");
};
// Hook the ProducerOnlineChanged event to handle changes in the online state of the producer.
edgeNode.ProducerOnlineChanged += (sender, eventArgs) =>
{
// Display the new producer online state.
Console.WriteLine($"{nameof(EasySparkplugEdgeNode.ProducerOnlineChanged)}: {edgeNode.ProducerOnline}");
};
// Hook the Poll event (but do not mark the polling as processed by ourselves).
edgeNode.Poll += (sender, eventArgs) =>
{
// Display when the component is polling for new data.
Console.WriteLine(nameof(EasySparkplugEdgeNode.Poll));
};
// Define a metric providing random integers.
var random = new Random();
edgeNode.Metrics.Add(new SparkplugMetric("MyMetric").ReadValueFunction(() => random.Next()));
// Start the edge node.
Console.WriteLine("The edge node is starting...");
edgeNode.Start();
Console.WriteLine("The edge node is started.");
Console.WriteLine();
// Let the user decide when to stop.
Console.WriteLine("Press Enter to stop the edge node...");
Console.ReadLine();
// Stop the edge node.
Console.WriteLine("The edge node is stopping...");
edgeNode.Stop();
Console.WriteLine("The edge node is stopped.");
}
}
}
' This example shows how to connect to the data source only when the producer is online.
'
' You can use any Sparkplug application, including our SparkplugCmd utility and the SparkplugApplicationConsoleDemo
' program, to subscribe to the edge node data.
'
' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-ConnectivityStudio/Latest/examples.html .
' Sparkplug examples in C# on GitHub: https://github.com/OPCLabs/Examples-ConnectivityStudio-CSharp .
' Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
' a commercial license in order to use Online Forums, and we reply to every post.
Imports OpcLabs.EasySparkplug
Namespace Global.SparkplugDocExamples.EdgeNode._EasySparkplugEdgeNode
Class DataSourceConnectionMode
Public Shared Sub Main1()
' Note that the default port for the "mqtt" scheme is 1883.
Dim hostDescriptor = New SparkplugHostDescriptor("mqtt://localhost")
' Instantiate the edge node object.
Dim edgeNode = New EasySparkplugEdgeNode(hostDescriptor, "easyGroup", "easySparkplugDemo")
' Configure the edge node to connect to the data source only when the producer is online. You can test it out
' e.g. by stopping or disconnecting from the MQTT broker.
'
' You can compare the output of this example with and without the statement below. With the statement, the
' Poll event will not be raised unless the producer is online. Without the statement, the Poll event will
' always be raised while the edge node is started, regardless of the MQTT broker connection state.
edgeNode.DataSourceConnectionMode = SparkplugDataSourceConnectionMode.WhenProducerOnline
' Hook the SystemConnectionStateChanged event to handle system connection state changes.
AddHandler edgeNode.SystemConnectionStateChanged,
Sub(sender, eventArgs)
' Display the new connection state (such as when the connection to the broker succeeds or fails).
Console.WriteLine($"{NameOf(EasySparkplugEdgeNode.SystemConnectionStateChanged)}: {eventArgs}")
End Sub
' Hook the ProducerOnlineChanged event to handle changes in the online state of the producer.
AddHandler edgeNode.ProducerOnlineChanged,
Sub(sender, eventArgs)
' Display the new producer online state.
Console.WriteLine($"{NameOf(EasySparkplugEdgeNode.ProducerOnlineChanged)}: {edgeNode.ProducerOnline}")
End Sub
' Hook the Poll event (but do not mark the polling as processed by ourselves).
AddHandler edgeNode.Poll,
Sub(sender, eventArgs)
' Display when the component Is polling for New data.
Console.WriteLine(NameOf(EasySparkplugEdgeNode.Poll))
End Sub
' Define a metric providing random integers.
Dim random = New Random()
edgeNode.Metrics.Add(New SparkplugMetric("MyMetric").ReadValueFunction(Function() random.Next()))
' Start the edge node.
Console.WriteLine("The edge node is starting...")
edgeNode.Start()
Console.WriteLine("The edge node is started.")
Console.WriteLine()
' Let the user decide when to stop.
Console.WriteLine("Press Enter to stop the edge node...")
Console.ReadLine()
' Stop the edge node.
Console.WriteLine("The edge node is stopping...")
edgeNode.Stop()
Console.WriteLine("The edge node is stopped.")
End Sub
End Class
End Namespace
