Connectivity Software User's Guide and Reference
Examples - Sparkplug Consumer - Subscribe to payloads from an edge node

.NET

// This example shows how to subscribe to the payload with all metrics of a given edge node and display the received payload
// with each notification.
//
// In order to publish or observe messages for this example, start the SparkplugEdgeNodeConsoleDemo program first.
//
// 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 System.Collections.Generic;
using OpcLabs.EasySparkplug;
using OpcLabs.EasySparkplug.OperationModel;

namespace SparkplugDocExamples.Consumer._EasySparkplugConsumer
{
    class SubscribeEdgeNodePayload
    {
        public static void Overload1()
        {
            // Note that the default port for the "mqtt" scheme is 1883.
            var hostDescriptor = new SparkplugHostDescriptor("mqtt://localhost");

            // Instantiate the consumer object and hook events.
            var consumer = new EasySparkplugConsumer();
            consumer.PayloadNotification += consumer_Overload1_PayloadNotification;

            Console.WriteLine("Subscribing...");
            consumer.SubscribeEdgeNodePayload(hostDescriptor, "easyGroup", "easySparkplugDemo");

            Console.WriteLine("Processing notifications for 20 seconds...");
            System.Threading.Thread.Sleep(20 * 1000);

            Console.WriteLine("Unsubscribing...");
            consumer.UnsubscribeAllPayloads();

            Console.WriteLine("Waiting for 5 seconds...");
            System.Threading.Thread.Sleep(5 * 1000);

            Console.WriteLine("Finished.");
        }


        static void consumer_Overload1_PayloadNotification(object sender, EasySparkplugPayloadNotificationEventArgs eventArgs)
        {
            // Handle different types of notifications.
            Console.WriteLine();
            switch (eventArgs.NotificationType)
            {
                case SparkplugNotificationType.Connect:
                    Console.WriteLine($"Connected to Sparkplug host, client ID: {eventArgs.ClientId}.");
                    break;
                case SparkplugNotificationType.Disconnect:
                    Console.WriteLine("Disconnected from Sparkplug host.");
                    break;
                case SparkplugNotificationType.Data:
                case SparkplugNotificationType.Birth:
                    Console.WriteLine("Received birth or data message from Sparkplug host.");
                    // Display the metrics name and data for each metric delivered in the payload.
                    foreach (KeyValuePair<string, SparkplugMetricElement> pair in eventArgs.Payload)
                        Console.WriteLine($"{pair.Key}: {pair.Value.MetricData}");
                    break;
                case SparkplugNotificationType.Death:
                    Console.WriteLine("Received death message from Sparkplug host.");
                    break;
            }
            if (!eventArgs.Succeeded)
                Console.WriteLine($"*** Failure: {eventArgs.ErrorMessageBrief}");
        }
    }
}
' This example shows how to subscribe to the payload with all metrics of a given edge node and display the received payload
' with each notification.
'
' In order to publish or observe messages for this example, start the SparkplugEdgeNodeConsoleDemo program first.
'
' 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
Imports OpcLabs.EasySparkplug.OperationModel

Namespace Global.SparkplugDocExamples.Consumer._EasySparkplugConsumer
    Class SubscribeEdgeNodePayload
        Public Shared Sub Overload1()
            ' Note that the default port for the "mqtt" scheme is 1883.
            Dim hostDescriptor = New SparkplugHostDescriptor("mqtt://localhost")

            ' Instantiate the consumer object and hook events.
            Dim consumer = New EasySparkplugConsumer()
            AddHandler consumer.PayloadNotification, AddressOf consumer_Overload1_PayloadNotification

            Console.WriteLine("Subscribing...")
            consumer.SubscribeEdgeNodePayload(hostDescriptor, "easyGroup", "easySparkplugDemo")

            Console.WriteLine("Processing notifications for 20 seconds...")
            Threading.Thread.Sleep(20 * 1000)

            Console.WriteLine("Unsubscribing...")
            consumer.UnsubscribeAllPayloads()

            Console.WriteLine("Waiting for 5 seconds...")
            Threading.Thread.Sleep(5 * 1000)

            Console.WriteLine("Finished.")
        End Sub

        Private Shared Sub consumer_Overload1_PayloadNotification(ByVal sender As Object, ByVal eventArgs As EasySparkplugPayloadNotificationEventArgs)
            ' Handle different types of notifications.
            Console.WriteLine()
            Select Case eventArgs.NotificationType
                Case SparkplugNotificationType.Connect
                    Console.WriteLine($"Connected to Sparkplug host, client ID: {eventArgs.ClientId}.")
                Case SparkplugNotificationType.Disconnect
                    Console.WriteLine("Disconnected from Sparkplug host.")
                Case SparkplugNotificationType.Data,
                    SparkplugNotificationType.Birth
                    Console.WriteLine("Received birth or data message from Sparkplug host.")
                    ' Display the metrics name and data for each metric delivered in the payload.
                    For Each pair As KeyValuePair(Of String, SparkplugMetricElement) In eventArgs.Payload
                        Console.WriteLine($"{pair.Key}: {pair.Value.MetricData}")
                    Next
                Case SparkplugNotificationType.Death
                    Console.WriteLine("Received death message from Sparkplug host.")
            End Select
            If Not eventArgs.Succeeded Then
                Console.WriteLine($"*** Failure: {eventArgs.ErrorMessageBrief}")
            End If
        End Sub
    End Class
End Namespace

 

See Also

Reference

Installed Examples - Sparkplug Console

Rapid Toolkit for Sparkplug