QuickOPC User's Guide and Reference
CustomPropertyValueDictionary Property (_UAWriterGroupDescriptor)
Example 



OpcLabs.EasyOpcUA Assembly > OpcLabs.EasyOpc.UA.PubSub.ComTypes Namespace > _UAWriterGroupDescriptor Interface : CustomPropertyValueDictionary Property
Specifies additional properties for the configured PubSub object.
Syntax
'Declaration
 
<NotNullAttribute()>
Property CustomPropertyValueDictionary As UAKeyValueDictionary
'Usage
 
Dim instance As _UAWriterGroupDescriptor
Dim value As UAKeyValueDictionary
 
instance.CustomPropertyValueDictionary = value
 
value = instance.CustomPropertyValueDictionary
[NotNull()]
UAKeyValueDictionary CustomPropertyValueDictionary {get; set;}
[NotNull()]
property UAKeyValueDictionary^ CustomPropertyValueDictionary {
   UAKeyValueDictionary^ get();
   void set (    UAKeyValueDictionary^ value);
}
Remarks

In OpcLabs.EasyOpc.UA.PubSub.UAWriterGroupDescriptor, this property contains the custom property values for the reader group that will be used to access the specified writer group. Similarly, in OpcLabs.EasyOpc.UA.PubSub.UADataSetWriterDescriptor, this property contains the custom property values for the dataset reader that will be used to access the specified dataset writer.

Example

.NET

// This example shows how to subscribe to all dataset messages on an OPC-UA PubSub connection with MQTT (JSON or UADP
// mapping) using TCP, and store a copy of all received messages into a file system.
//
// A related example (SubscribeDataSet.MqttFromFileStorage) shows hot the captured messages can be replayed from the file
// system, e.g. for troubleshooting.
//
// The following package needs to be referenced in your project (or otherwise made available) for the MQTT transport to 
// work.
// - OpcLabs.MqttNet
// Refer to the documentation for more information.

using System;
using System.Collections.Generic;
using System.Threading;
using OpcLabs.EasyOpc.UA.AddressSpace;
using OpcLabs.EasyOpc.UA.PubSub;
using OpcLabs.EasyOpc.UA.PubSub.OperationModel;

namespace UADocExamples.PubSub._EasyUASubscriber
{
    partial class SubscribeDataSet
    {
        public static void MqttTcpSaveCopy()
        {
            // Define the PubSub connection we will work with. Uses implicit conversion from a string.
            // Default port with MQTT is 1883.
            UAPubSubConnectionDescriptor pubSubConnectionDescriptor = "mqtt://opcua-pubsub.demo-this.com";
            // Configure the PubSub connection so that a copy of the received messages is stored into the file system, under
            // the specified "root" directory.
            pubSubConnectionDescriptor.CustomPropertyValueDictionary[
                new UAQualifiedName("{OpcLabs}", "MqttFileCopyReceivedRoot")] = @"C:\MqttReceived";

            // Define the arguments for subscribing to the dataset, specifying the MQTT topic name.
            var subscribeDataSetArguments = new UASubscribeDataSetArguments(pubSubConnectionDescriptor)
            {
                DataSetSubscriptionDescriptor = {CommunicationParameters = {BrokerDataSetReaderTransportParameters =
                {
                    QueueName = "opcuademo/#"
                }}}
            };

            // Instantiate the subscriber object and hook events.
            var subscriber = new EasyUASubscriber();
            subscriber.DataSetMessage += subscriber_DataSetMessage_MqttTcpSaveCopy;

            Console.WriteLine("Subscribing...");
            subscriber.SubscribeDataSet(subscribeDataSetArguments);

            Console.WriteLine("Processing dataset message events for 20 seconds...");
            Thread.Sleep(20 * 1000);

            Console.WriteLine("Unsubscribing...");
            subscriber.UnsubscribeAllDataSets();

            Console.WriteLine("Waiting for 1 second...");
            // Unsubscribe operation is asynchronous, messages may still come for a short while.
            Thread.Sleep(1 * 1000);

            Console.WriteLine("Finished.");
        }

        static void subscriber_DataSetMessage_MqttTcpSaveCopy(object sender, EasyUADataSetMessageEventArgs e)
        {
            // Display the dataset.
            if (e.Succeeded)
            {
                // An event with null DataSetData just indicates a successful connection.
                if (!(e.DataSetData is null))
                {
                    Console.WriteLine();
                    Console.WriteLine($"Dataset data: {e.DataSetData}");
                    foreach (KeyValuePair<string, UADataSetFieldData> pair in e.DataSetData.FieldDataDictionary)
                        Console.WriteLine(pair);
                }
            }
            else
            {
                Console.WriteLine();
                Console.WriteLine($"*** Failure: {e.ErrorMessage}");
            }
        }
    }
}
# This example shows how to subscribe to all dataset messages on an OPC-UA PubSub connection with MQTT (JSON or UADP
# mapping) using TCP, and store a copy of all received messages into a file system.
#
# A related example (SubscribeDataSet.MqttFromFileStorage) shows hot the captured messages can be replayed from the file
# system, e.g. for troubleshooting.
#
# The following package needs to be referenced in your project (or otherwise made available) for the MQTT transport to
# work.
# - OpcLabs.MqttNet
# Refer to the documentation for more information.

# The QuickOPC package is needed. Install it using "pip install opclabs_quickopc".
import opclabs_quickopc
import opclabs_mqttnet
import time

# Import .NET namespaces.
from OpcLabs.EasyOpc.UA.AddressSpace import *
from OpcLabs.EasyOpc.UA.PubSub import *
from OpcLabs.EasyOpc.UA.PubSub.OperationModel import *


def dataSetMessage(sender, e):
    # Display the dataset.
    if e.Succeeded:
        # An event with null DataSetData just indicates a successful connection.
        if e.DataSetData is not None:
            print('')
            print('Dataset data: ', e.DataSetData, sep='')
            for pair in e.DataSetData.FieldDataDictionary:
                print(pair)
    else:
        print('')
        print('*** Failure: ', e.ErrorMessageBrief, sep='')


# Define the PubSub connection we will work with. Uses implicit conversion from a string.
# Default port with MQTT is 1883.
pubSubConnectionDescriptor = UAPubSubConnectionDescriptor.op_Implicit('mqtt://opcua-pubsub.demo-this.com')
# Configure the PubSub connection so that a copy of the received messages is stored into the file system, under
# the specified "root" directory.
pubSubConnectionDescriptor.CustomPropertyValueDictionary.set_Item(
    UAQualifiedName('{OpcLabs}', 'MqttFileCopyReceivedRoot'), r'C:\MqttReceived')

# Define the arguments for subscribing to the dataset, specifying the MQTT topic name.
subscribeDataSetArguments = UASubscribeDataSetArguments(pubSubConnectionDescriptor)
subscribeDataSetArguments.DataSetSubscriptionDescriptor.CommunicationParameters.BrokerDataSetReaderTransportParameters.\
    QueueName = 'opcuademo/#'

# Instantiate the subscriber object and hook events.
subscriber = EasyUASubscriber()
subscriber.DataSetMessage += dataSetMessage

print('Subscribing...')
IEasyUASubscriberExtension.SubscribeDataSet(subscriber, subscribeDataSetArguments)

print('Processing dataset message events for 20 seconds...')
time.sleep(20)

print('Unsubscribing...')
subscriber.UnsubscribeAllDataSets()

print('Waiting for 1 second...')
# Unsubscribe operation is asynchronous, messages may still come for a short while.
time.sleep(1)

subscriber.DataSetMessage -= dataSetMessage

print('Finished.')
Requirements

Target Platforms: .NET Framework: Windows 10 (selected versions), Windows 11 (selected versions), Windows Server 2016, Windows Server 2022; .NET: Linux, macOS, Microsoft Windows

See Also