AccessReadOnlyConfiguration Method (IEasyUAPublishSubscribeClient)

Gives read-only access to PubSub configuration provided by the specified OPC UA server.

Syntax

[NotNull()]
IUAReadOnlyPubSubConfiguration AccessReadOnlyConfiguration( 
   UAEndpointDescriptor endpointDescriptor
)

[NotNull()]
IUAReadOnlyPubSubConfiguration^ AccessReadOnlyConfiguration( 
   UAEndpointDescriptor^ endpointDescriptor
)

'Declaration
 
<NotNullAttribute()>
Function AccessReadOnlyConfiguration( _
   ByVal endpointDescriptor As UAEndpointDescriptor _
) As IUAReadOnlyPubSubConfiguration

'Usage
 
Dim instance As IEasyUAPublishSubscribeClient
Dim endpointDescriptor As UAEndpointDescriptor
Dim value As IUAReadOnlyPubSubConfiguration
 
value = instance.AccessReadOnlyConfiguration(endpointDescriptor)

Parameters

endpointDescriptor: The endpoint descriptor of the OPC UA server containing the PubSub information model.

Return Value

Returns an interface that provides read-only access to PubSub configuration.

Exceptions

Exception Description

Exception	Description
System.ArgumentNullException	A `null` reference (`Nothing` in Visual Basic) is passed to a method that does not accept it as a valid argument. This is a usage error, i.e. it will never occur (the exception will not be thrown) in a correctly written program. Your code should not catch this exception.

System.ArgumentNullException

A null reference (Nothing in Visual Basic) is passed to a method that does not accept it as a valid argument.

This is a usage error, i.e. it will never occur (the exception will not be thrown) in a correctly written program. Your code should not catch this exception.

Remarks

You can use the HasConfigurationModel method to determine whether the given server provides a PubSub configuration model. Operations on the returned OpcLabs.EasyOpc.UA.PubSub.Configuration.IUAReadOnlyPubSubConfiguration will fail if it does not.

Example

.NET

COM

// This example obtains and prints out information about all published datasets in the OPC UA PubSub configuration.

using System;
using OpcLabs.BaseLib.Collections.Specialized;
using OpcLabs.EasyOpc.UA.OperationModel;
using OpcLabs.EasyOpc.UA.PubSub.Configuration;
using OpcLabs.EasyOpc.UA.PubSub.Configuration.Extensions;
using OpcLabs.EasyOpc.UA.PubSub.InformationModel;
using OpcLabs.EasyOpc.UA.PubSub.InformationModel.Extensions;

namespace UADocExamples.PubSub._IUAReadOnlyPubSubConfiguration
{
    partial class GetMethods
    {
        public static void PublishedDataSets()
        {
            // Instantiate the publish-subscribe client object.
            var publishSubscribeClient = new EasyUAPublishSubscribeClient();

            try
            {
                Console.WriteLine("Loading the configuration...");
                // Load the PubSub configuration from a file. The file itself is at the root of the project, and we have
                // specified that it has to be copied to the project's output directory.
                IUAReadOnlyPubSubConfiguration pubSubConfiguration = 
                    publishSubscribeClient.LoadReadOnlyConfiguration("UADemoPublisher-Default.uabinary");

                // Alternatively, using the statement below, you can access a live configuration residing in an OPC UA
                // Server with appropriate information model.
                //IUAReadOnlyPubSubConfiguration pubSubConfiguration =
                //    publishSubscribeClient.AccessReadOnlyConfiguration("opc.tcp://localhost:48010");

                // Get the names of all published datasets in the PubSub configuration.
                StringCollection publishedDataSetNames = pubSubConfiguration.ListAllPublishedDataSetNames();

                foreach (string publishedDataSetName in publishedDataSetNames)
                {
                    Console.WriteLine($"Published dataset: {publishedDataSetName}");

                    // You can use the statement below to obtain parameters of the published dataset.
                    //UAPublishedDataSetElement publishedDataSetElement = 
                    //    pubSubConfiguration.GetPublishedDataSetElement(publishedDataSetName);
                }
            }
            catch (UAException uaException)
            {
                Console.WriteLine($"*** Failure: {uaException.InnerException.Message}");
            }

            Console.WriteLine("Finished.");
        }

        // Example output:
        //
        //Loading the configuration...
        //Published dataset: Simple
        //Published dataset: AllTypes
        //Published dataset: MassTest
        //Published dataset: AllTypes-Dynamic
        //Finished.
    }
}

# This example obtains and prints out information about all published datasets in the OPC UA PubSub configuration.

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

# Import .NET namespaces.
from OpcLabs.BaseLib import *
#from OpcLabs.EasyOpc.UA import *
from OpcLabs.EasyOpc.UA.OperationModel import *
from OpcLabs.EasyOpc.UA.PubSub.Configuration.Extensions import *
from OpcLabs.EasyOpc.UA.PubSub.InformationModel import *
from OpcLabs.EasyOpc.UA.PubSub.InformationModel.Extensions import *
from OpcLabs.EasyOpc.UA.PubSub.OperationModel import *


# Instantiate the publish-subscribe client object.
publishSubscribeClient = EasyUAPublishSubscribeClient()

try:
    print('Loading the configuration...')
    # Load the PubSub configuration from a file. The file itself is in this script's directory.
    pubSubConfiguration = IEasyUAPublishSubscribeClientExtension.LoadReadOnlyConfiguration(publishSubscribeClient,
        'UADemoPublisher-Default.uabinary')

    # Alternatively, using the statement below, you can access a live configuration residing in an OPC UA
    # Server with appropriate information model.
    #pubSubConfiguration = publishSubscribeClient.AccessReadOnlyConfiguration(
    #    UAEndpointDescriptor('opc.tcp://localhost:48010'))

    # Get the names of all published datasets in the PubSub configuration.
    publishedDataSetNames = IUAReadOnlyPubSubConfigurationExtension.ListAllPublishedDataSetNames(pubSubConfiguration)

    for publishedDataSetName in publishedDataSetNames:
        print('Published dataset: ', publishedDataSetName, sep='')

        # You can use the statement below to obtain parameters of the published dataset.
        #publishedDataSetElement = IUAReadOnlyPubSubConfigurationExtension.GetPublishedDataSetElement(
        #    pubSubConfiguration,
        #    publishedDataSetName)

except UAException as uaException:
    print('*** Failure: ' + uaException.GetBaseException().Message)
    exit()

print('Finished.')

' This example obtains and prints out information about all published datasets in the OPC UA PubSub configuration.

Imports OpcLabs.EasyOpc.UA.OperationModel
Imports OpcLabs.EasyOpc.UA.PubSub.Configuration
Imports OpcLabs.EasyOpc.UA.PubSub.Configuration.Extensions
Imports OpcLabs.EasyOpc.UA.PubSub.InformationModel
Imports OpcLabs.EasyOpc.UA.PubSub.InformationModel.Extensions

Namespace PubSub._IUAReadOnlyPubSubConfiguration
    Partial Friend Class GetMethods
        Public Shared Sub PublishedDataSets()

            ' Instantiate the publish-subscribe client object.
            Dim publishSubscribeClient = New EasyUAPublishSubscribeClient()

            Try
                Console.WriteLine("Loading the configuration...")
                ' Load the PubSub configuration from a file. The file itself is at the root of the project, and we have
                ' specified that it has to be copied to the project's output directory.
                Dim pubSubConfiguration As IUAReadOnlyPubSubConfiguration =
                    publishSubscribeClient.LoadReadOnlyConfiguration("UADemoPublisher-Default.uabinary")

                ' Alternatively, using the statement below, you can access a live configuration residing in an OPC UA
                ' Server with appropriate information model.
                'Dim pubSubConfiguration As IUAReadOnlyPubSubConfiguration =
                '    publishSubscribeClient.AccessReadOnlyConfiguration("opc.tcp://localhost:48010")

                ' Get the names of all published datasets in the PubSub configuration.
                Dim publishedDataSetNames = pubSubConfiguration.ListAllPublishedDataSetNames()

                For Each publishedDataSetName As String In publishedDataSetNames
                    Console.WriteLine($"Published dataset: {publishedDataSetName}")

                    ' You can use the statement below to obtain parameters of the published dataset.
                    'Dim publishedDataSetElement As UAPublishedDataSetElement =
                    '    pubSubConfiguration.GetPublishedDataSetElement(publishedDataSetName)
                Next publishedDataSetName
            Catch uaException As UAException
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException.Message)
            End Try

            Console.WriteLine("Finished...")
        End Sub
    End Class

    ' Example output
    '
    'Loading the configuration...
    'Published dataset Simple
    'Published dataset: AllTypes
    'Published dataset: MassTest
    'Published dataset: AllTypes-Dynamic
    'Finished.

End Namespace

Object Pascal
VBScript

// This example obtains and prints out information about all published datasets in the OPC UA PubSub configuration.

class procedure GetMethods.PublishedDataSets;
var
  //EndpointDescriptor: _UAEndpointDescriptor;
  I: Integer;
  PublishedDataSetName: string;
  PublishedDataSetNames: _StringCollection;
  //PublishedDataSetElement: _UAPublishedDataSetElement;
  PublishSubscribeClient: _EasyUAPublishSubscribeClient;
  PubSubConfiguration: _UAReadOnlyPubSubConfiguration;
begin
  // Instantiate the publish-subscribe client object.
  PublishSubscribeClient := CoEasyUAPublishSubscribeClient.Create;

  try
    WriteLn('Loading the configuration...');
    // Load the PubSub configuration from a file. The file itself is included alongside the script.
    PubSubConfiguration := PublishSubscribeClient.LoadReadOnlyConfiguration('UADemoPublisher-Default.uabinary');

    // Alternatively, using the statements below, you can access a live configuration residing in an OPC UA Server
    // with appropriate information model.
    //EndpointDescriptor := CoUAEndpointDescriptor.Create;
    //EndpointDescriptor.UrlString := 'opc.tcp://localhost:48010';
    //PubSubConfiguration := PublishSubscribeClient.AccessReadOnlyConfiguration(EndpointDescriptor);

    // Get the names of PubSub connections in the configuration, regardless of the folder they reside in.
    PublishedDataSetNames := PubSubConfiguration.ListAllPublishedDataSetNames;

    for I := 0 to PublishedDataSetNames.Count-1 do
    begin
      PublishedDataSetName := PublishedDataSetNames[I];
      WriteLn('Published dataset: ', PublishedDataSetName);

      // You can use the statement below to obtain parameters of the published dataset.
      //PublishedDataSetElement := PubSubConfiguration.GetPublishedDataSetElement(Unassigned, PublishedDataSetName);
    end;
  except
    on E: EOleException do
    begin
      WriteLn(Format('*** Failure: %s', [E.GetBaseException.Message]));
    end;
  end;

  WriteLn('Finished.');
end;

// Example output:
//
//Loading the configuration...
//Published dataset: Simple
//Published dataset: AllTypes
//Published dataset: MassTest
//Published dataset: AllTypes-Dynamic
//Finished.

Rem This example obtains and prints out information about all published datasets in the OPC UA PubSub configuration.

Option Explicit

' Instantiate the publish-subscribe client object.
Dim PublishSubscribeClient: Set PublishSubscribeClient = CreateObject("OpcLabs.EasyOpc.UA.PubSub.InformationModel.EasyUAPublishSubscribeClient")

On Error Resume Next
DumpPublishedDataSets
If Err.Number <> 0 Then
    WScript.Echo "*** Failure: " & Err.Source & ": " & Err.Description
    WScript.Quit
End If
On Error Goto 0

WScript.Echo "Finished."



Sub DumpPublishedDataSets()
    WScript.Echo "Loading the configuration..."
    ' Load the PubSub configuration from a file. The file itself is included alongside the script.
    Dim PubSubConfiguration: Set PubSubConfiguration = PublishSubscribeClient.LoadReadOnlyConfiguration("UADemoPublisher-Default.uabinary")

    ' Alternatively, using the statements below, you can access a live configuration residing in an OPC UA Server
    ' with appropriate information model.
    'Dim EndpointDescriptor: Set EndpointDescriptor = CreateObject("OpcLabs.EasyOpc.UA.UAEndpointDescriptor")
    'EndpointDescriptor.UrlString = "opc.tcp://localhost:48010"
    'Dim PubSubConfiguration: Set PubSubConfiguration = PublishSubscribeClient.AccessReadOnlyConfiguration(EndpointDescriptor)

    ' Get the names of PubSub connections in the configuration, regardless of the folder they reside in.
    Dim PublishedDataSetNames: Set PublishedDataSetNames = PubSubConfiguration.ListAllPublishedDataSetNames

    Dim publishedDataSetName: For Each publishedDataSetName In PublishedDataSetNames
        WScript.Echo "Published dataset: " & publishedDataSetName

        ' You can use the statement below to obtain parameters of the published dataset.
        'Dim PublishedDataSetElement: Set PublishedDataSetElement = PubSubConfiguration.GetPublishedDataSetElement(Nothing, publishedDataSetName)
    Next
End Sub



' Example output:
'
'Loading the configuration...
'Published dataset: Simple
'Published dataset: AllTypes
'Published dataset: MassTest
'Published dataset: AllTypes-Dynamic
'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

Reference

IEasyUAPublishSubscribeClient Interface
IEasyUAPublishSubscribeClient Members

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