RegisterToGds Method (EasyUAApplicationCore)

Creates an application registration in the GDS, assigning it a new application ID. Existing registrations with the same application URI are removed first.

Syntax

Visual Basic
C#
C++/CLI

'Declaration
 
Public Function RegisterToGds( _
   ByVal gdsEndpointDescriptor As UAEndpointDescriptor _
) As UANodeId

'Usage
 
Dim instance As EasyUAApplicationCore
Dim gdsEndpointDescriptor As UAEndpointDescriptor
Dim value As UANodeId
 
value = instance.RegisterToGds(gdsEndpointDescriptor)

public UANodeId RegisterToGds( 
   UAEndpointDescriptor gdsEndpointDescriptor
)

public:
UANodeId^ RegisterToGds( 
   UAEndpointDescriptor^ gdsEndpointDescriptor
)

Parameters

gdsEndpointDescriptor

The endpoint of OPC UA Global Discovery Server (GDS).

Because the OpcLabs.EasyOpc.UA.UAEndpointDescriptor has implicit conversions from System.String and System.Uri, in languages that support implicit conversion operators (such as C# or VB.NET), you can simply use a string (representing the endpoint URL, or a so-called OPC UA endpoint descriptor string), or a System.Uri object, in place of this parameter, and the corresponding endpoint descriptor will be constructed automatically. When the implicit conversion operators are not supported (such as with Python.NET), you can use the FromString or FromUri static method instead.

If you are using OPC Wizard (for server development), an implicit conversion from OpcLabs.EasyOpc.UA.EasyUAServerCore can be used in the same way to simply pass the server object in place of this parameter, which will use its OpcLabs.EasyOpc.UA.EasyUAServerCore.EffectiveServerDescriptor property for the connection.

The value of this parameter cannot be null (Nothing in Visual Basic).

Return Value

Returns the new application ID.

Because there is an implicit conversion from OpcLabs.EasyOpc.UA.AddressSpace.UANodeId to OpcLabs.EasyOpc.UA.UANodeDescriptor, in languages that support implicit conversion operators (such as C# or VB.NET), you can simply use the returned OpcLabs.EasyOpc.UA.AddressSpace.UANodeId in any place where the OpcLabs.EasyOpc.UA.UANodeDescriptor is expected as input, and the corresponding node descriptor will be constructed automatically.

Also, because the OpcLabs.EasyOpc.UA.AddressSpace.UANodeId has an implicit conversion to System.String, and it converts to the expanded text of the node Id (ExpandedText), in languages that support implicit conversion operators (such as C# or VB.NET), you can simply use the returned OpcLabs.EasyOpc.UA.AddressSpace.UANodeId in any place where expanded text of a node Id (a string) is expected as input, and the corresponding expanded text will be taken automatically from the node Id.

This method never returns null (Nothing in Visual Basic).

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.
OpcLabs.EasyOpc.UA.OperationModel.UAException	The OPC UA operation has failed. This operation exception in uniformly used to allow common handling of various kinds of errors. The System.Exception.InnerException always contains information about the actual error cause. This is an operation error that depends on factors external to your program, and thus cannot be always avoided. Your code must handle it appropriately.

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.

OpcLabs.EasyOpc.UA.OperationModel.UAException

The OPC UA operation has failed. This operation exception in uniformly used to allow common handling of various kinds of errors. The System.Exception.InnerException always contains information about the actual error cause.

This is an operation error that depends on factors external to your program, and thus cannot be always avoided. Your code must handle it appropriately.

Remarks

This method facilitates the registration of the application with a GDS, enabling it to be discovered by other OPC UA clients and servers. The registration process involves the application providing its details to the GDS, which then assigns a unique NodeId to the application. This NodeId can be used by other clients and servers to discover and interact with the registered application.

The difference between the RegisterToGds and UpdateGdsRegistration methods is that the RegisterToGds method always obtains a new application ID, whereas the UpdateGdsRegistration method attempts to reuse the existing application ID, if known. Neither of these methods requires the GDS registration be in any particular state for it to succeed, and both methods assure that after a successful execution, there is one and only one registration in the given GDS for this application.

The identity of the application itself is carried by its application URI, as given by the OpcLabs.EasyOpc.UA.Discovery.UAApplicationElement.ApplicationUriString returned by the OpcLabs.EasyOpc.UA.Application.Extensions.IEasyUAClientServerApplicationExtension.GetApplicationElement. Methods on this interface that manipulate or inspect the GDS registration use the application URI to identify the registration records belonging to this application.

Example

CSharp
VB.NET
Object Pascal
PHP
Python

// Shows how to create an application registration in the GDS, assigning it a new application ID.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
// OPC client and subscriber examples in C# on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-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.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.AddressSpace;
using OpcLabs.EasyOpc.UA.Application;
using OpcLabs.EasyOpc.UA.Application.Extensions;
using OpcLabs.EasyOpc.UA.Extensions;
using OpcLabs.EasyOpc.UA.OperationModel;

namespace UADocExamples.Application._IEasyUAClientServerApplication
{
    class RegisterToGds
    {
        public static void Main1()
        {
            // Define which GDS we will work with.
            UAEndpointDescriptor gdsEndpointDescriptor =
                ((UAEndpointDescriptor)"opc.tcp://opcua.demo-this.com:58810/GlobalDiscoveryServer")
                .WithUserNameIdentity("appadmin", "demo");

            // Obtain the application interface.
            EasyUAApplication application = EasyUAApplication.Instance;

            // Display which application we are about to work with.
            Console.WriteLine("Application URI string: {0}",
                application.GetApplicationElement().ApplicationUriString);

            // Create an application registration in the GDS, assigning it a new application ID.
            UANodeId applicationId;
            try
            {
                applicationId = application.RegisterToGds(gdsEndpointDescriptor);
            }
            catch (UAException uaException)
            {
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException().Message);
                return;
            }

            // Display results
            Console.WriteLine("Application ID: {0}", applicationId);
        }
    }
}

' Shows how to create an application registration in the GDS, assigning it a new application ID.
'
' Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
' OPC client and subscriber examples in VB.NET on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-VBNET .
' 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.EasyOpc.UA
Imports OpcLabs.EasyOpc.UA.AddressSpace
Imports OpcLabs.EasyOpc.UA.Application
Imports OpcLabs.EasyOpc.UA.Application.Extensions
Imports OpcLabs.EasyOpc.UA.Extensions
Imports OpcLabs.EasyOpc.UA.OperationModel

Namespace Application._IEasyUAClientServerApplication
    Friend Class RegisterToGds
        Public Shared Sub Main1()

            ' Define which GDS we will work with.
            Dim gdsEndpointDescriptor As UAEndpointDescriptor =
                New UAEndpointDescriptor("opc.tcp://opcua.demo-this.com:58810/GlobalDiscoveryServer") _
                .WithUserNameIdentity("appadmin", "demo")

            ' Obtain the application interface.
            Dim application As EasyUAApplication = EasyUAApplication.Instance

            ' Display which application we are about to work with.
            Console.WriteLine("Application URI string: {0}",
                application.GetApplicationElement().ApplicationUriString)

            ' Create an application registration in the GDS, assigning it a new application ID.
            Dim applicationId As UANodeId
            Try
                applicationId = application.RegisterToGds(gdsEndpointDescriptor)
            Catch uaException As UAException
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException.Message)
                Exit Sub
            End Try

            ' Display results
            Console.WriteLine("Application ID: {0}", applicationId)
        End Sub
    End Class
End Namespace

// Shows how to create an application registration in the GDS, assigning it a new application ID.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
// OPC client and subscriber examples in Object Pascal (Delphi) on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-OP .
// 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.

class procedure RegisterToGds.Main;
var
  Application: TEasyUAApplication;
  ApplicationId: _UANodeId;
  GdsEndpointDescriptor: _UAEndpointDescriptor;
begin
  // Define which GDS we will work with.
  GdsEndpointDescriptor := CoUAEndpointDescriptor.Create;
  GdsEndpointDescriptor.UrlString := 'opc.tcp://opcua.demo-this.com:58810/GlobalDiscoveryServer';
  GdsEndpointDescriptor.UserIdentity.UserNameTokenInfo.UserName := 'appadmin';
  GdsEndpointDescriptor.UserIdentity.UserNameTokenInfo.Password := 'demo';

  // Obtain the application interface.
  Application := TEasyUAApplication.Create(nil);

  // Display which application we are about to work with.
  WriteLn('Application URI string: ', Application.GetApplicationElement.ApplicationUriString);

  // Create an application registration in the GDS, assigning it a new application ID.
  try
    ApplicationId := Application.RegisterToGds(gdsEndpointDescriptor);
  except
    on E: EOleException do
    begin
      WriteLn(Format('*** Failure: %s', [E.GetBaseException.Message]));
    end;
  end;

  // Display results
  WriteLn('Application ID: ', ApplicationId.ToString);
end;

// Shows how to create an application registration in the GDS, assigning it a new application ID.
//
// Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
// OPC client and subscriber examples in PHP on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-PHP .
// 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.

// Define which GDS we will work with.
$GdsEndpointDescriptor = new COM("OpcLabs.EasyOpc.UA.UAEndpointDescriptor");
$GdsEndpointDescriptor->UrlString = "opc.tcp://opcua.demo-this.com:58810/GlobalDiscoveryServer";
$GdsEndpointDescriptor->UserIdentity->UserNameTokenInfo->UserName = "appadmin";
$GdsEndpointDescriptor->UserIdentity->UserNameTokenInfo->Password = "demo";

// Obtain the application interface.
$Application = new COM("OpcLabs.EasyOpc.UA.Application.EasyUAApplication");

// Display which application we are about to work with.
printf("Application URI string: %s\n", $Application->GetApplicationElement->ApplicationUriString);

// Create an application registration in the GDS, assigning it a new application ID.
try
{
    $ApplicationId = $Application->RegisterToGds($GdsEndpointDescriptor);
}
catch (com_exception $e)
{
    printf("*** Failure: %s\n", $e->getMessage());
    exit();
}

// Display results
printf("Application ID: %s\n", $ApplicationId);

# Shows how to create an application registration in the GDS, assigning it a new application ID.
#
# Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
# OPC client and subscriber examples in Python on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-Python .
# 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.
# The QuickOPC package is needed. Install it using "pip install opclabs_quickopc".
import opclabs_quickopc

# Import .NET namespaces.
from OpcLabs.EasyOpc.UA import *
from OpcLabs.EasyOpc.UA.Application import *
from OpcLabs.EasyOpc.UA.Application.Extensions import *
from OpcLabs.EasyOpc.UA.Extensions import *
from OpcLabs.EasyOpc.UA.OperationModel import *


# Define which GDS we will work with.
gdsEndpointDescriptor = UAEndpointDescriptor('opc.tcp://opcua.demo-this.com:58810/GlobalDiscoveryServer')
gdsEndpointDescriptor = UAEndpointDescriptorExtension.WithUserNameIdentity(gdsEndpointDescriptor,
                                                                           'appadmin', 'demo')

# Obtain the application interface.
application = EasyUAApplication.Instance

# Display which application we are about to work with.
applicationElement = IEasyUAClientServerApplicationExtension.GetApplicationElement(application)
print('Application URI string: ', applicationElement.ApplicationUriString, sep='')

# Create an application registration in the GDS, assigning it a new application ID.
try:
    print('Registering to GDS...')
    applicationId = application.RegisterToGds(gdsEndpointDescriptor)
except UAException as uaException:
    print('*** Failure: ' + uaException.GetBaseException().Message)
    exit()

# Display results.
print('Application ID: ', applicationId, sep='')

print()
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

Reference

EasyUAApplicationCore Class
EasyUAApplicationCore Members

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