OPC Studio User's Guide and Reference
ObtainNewCertificate(IEasyUAClientServerApplication,UAEndpointDescriptor) Method
Example 



OpcLabs.EasyOpcUA Assembly > OpcLabs.EasyOpc.UA.Application.Extensions Namespace > IEasyUAClientServerApplicationExtension Class > ObtainNewCertificate Method : ObtainNewCertificate(IEasyUAClientServerApplication,UAEndpointDescriptor) Method
The OPC UA client/server application object that will perform the operation.

In client applications, this is typically obtained by calling System.IServiceProvider.GetService(System.Type) on the OpcLabs.EasyOpc.UA.IEasyUAClient (EasyUAClient object) with the type of OpcLabs.EasyOpc.UA.Application.IEasyUAClientServerApplication as an argument.

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

The GDS endpoint acting as OPC UA certificate manager (CM).

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.

Also, because the OpcLabs.EasyOpc.UA.Discovery.UAApplicationElement and OpcLabs.EasyOpc.UA.Discovery.UADiscoveryElement have an implicit conversion to OpcLabs.EasyOpc.UA.UAEndpointDescriptor, in languages that support implicit conversion operators (such as C# or VB.NET), you can simply use a OpcLabs.EasyOpc.UA.Discovery.UAApplicationElement or OpcLabs.EasyOpc.UA.Discovery.UADiscoveryElement (results from OPC UA discovery) 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 convert a (non-null) OpcLabs.EasyOpc.UA.Discovery.UAApplicationElement or OpcLabs.EasyOpc.UA.Discovery.UADiscoveryElement to OpcLabs.EasyOpc.UA.UAEndpointDescriptor using the OpcLabs.EasyOpc.UA.Discovery.UAApplicationElement.ToUAEndpointDescriptor or OpcLabs.EasyOpc.UA.Discovery.UADiscoveryElement.ToUAEndpointDescriptor 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).

Obtains a new certificate from the certificate manager, specifying the GDS endpoint descriptor.
Syntax
'Declaration
 
<ExtensionAttribute()>
<NotNullAttribute()>
Public Overloads Shared Function ObtainNewCertificate( _
   ByVal application As IEasyUAClientServerApplication, _
   ByVal gdsEndpointDescriptor As UAEndpointDescriptor _
) As IPkiCertificate
'Usage
 
Dim application As IEasyUAClientServerApplication
Dim gdsEndpointDescriptor As UAEndpointDescriptor
Dim value As IPkiCertificate
 
value = IEasyUAClientServerApplicationExtension.ObtainNewCertificate(application, gdsEndpointDescriptor)

Parameters

application
The OPC UA client/server application object that will perform the operation.

In client applications, this is typically obtained by calling System.IServiceProvider.GetService(System.Type) on the OpcLabs.EasyOpc.UA.IEasyUAClient (EasyUAClient object) with the type of OpcLabs.EasyOpc.UA.Application.IEasyUAClientServerApplication as an argument.

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

gdsEndpointDescriptor
The GDS endpoint acting as OPC UA certificate manager (CM).

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.

Also, because the OpcLabs.EasyOpc.UA.Discovery.UAApplicationElement and OpcLabs.EasyOpc.UA.Discovery.UADiscoveryElement have an implicit conversion to OpcLabs.EasyOpc.UA.UAEndpointDescriptor, in languages that support implicit conversion operators (such as C# or VB.NET), you can simply use a OpcLabs.EasyOpc.UA.Discovery.UAApplicationElement or OpcLabs.EasyOpc.UA.Discovery.UADiscoveryElement (results from OPC UA discovery) 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 convert a (non-null) OpcLabs.EasyOpc.UA.Discovery.UAApplicationElement or OpcLabs.EasyOpc.UA.Discovery.UADiscoveryElement to OpcLabs.EasyOpc.UA.UAEndpointDescriptor using the OpcLabs.EasyOpc.UA.Discovery.UAApplicationElement.ToUAEndpointDescriptor or OpcLabs.EasyOpc.UA.Discovery.UADiscoveryElement.ToUAEndpointDescriptor 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 certificate obtained from the certificate manager.

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

Exceptions
ExceptionDescription

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.

An operation that the thread was execution has been cancelled.

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

The ObtainNewCertificate methods obtain a new application own certificate from the certificate manager, and store it for subsequent usage.

The operation is synchronous. It can take considerable time to execute, because it involves multiple steps, and waiting for a finalization of the request by the GDS (see the OpcLabs.EasyOpc.UA.Gds.IEasyUACertificateManagement.FinishRequest method).

For an alternative based on asynchronous programming model (APM, System.IAsyncResult) pattern, see the BeginObtainNewCertificate method and related extension methods.

For a task-based asynchronous programming pattern alternative, see the ObtainNewCertificateAsync(IEasyUAClientServerApplication,UAEndpointDescriptor) extension method and its overloads.

The operation is synchronous. It can take considerable time to execute, because it involves multiple steps, and waiting for a finalization of the request by the GDS (see the OpcLabs.EasyOpc.UA.Gds.IEasyUACertificateManagement.FinishRequest method).

For an alternative based on asynchronous programming model (APM, System.IAsyncResult) pattern, see the BeginObtainNewCertificate method and related extension methods.

For a task-based asynchronous programming pattern alternative, see the ObtainNewCertificateAsync(IEasyUAClientServerApplication,UAEndpointDescriptor) extension method and its overloads.

This is an extension method (info: C#, VB.NET). In languages that have support for extensions methods (such as C# and VB.NET), you can use the extension method as if it were a regular method on the object that is its first parameter. In other languages (such as with Python.NET), you will call the extension as a static method, and pass it the object on which it acts as its first parameter.

Example
// Shows how to obtain a new application certificate from the certificate manager (GDS), and store it for subsequent usage.
//
// 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.BaseLib.Security.Cryptography.PkiCertificates;
using OpcLabs.EasyOpc.UA;
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
{
    partial class ObtainNewCertificate
    {
        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);
            
            // Obtain a new application certificate from the certificate manager (GDS), and store it for subsequent usage.
            IPkiCertificate certificate;
            try
            {
                certificate = application.ObtainNewCertificate(gdsEndpointDescriptor);
            }
            catch (UAException uaException)
            {
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException().Message);
                return;
            }

            // Display results
            Console.WriteLine("Certificate: {0}", certificate);
        }
    }
}
' Shows how to obtain a new application certificate from the certificate manager (GDS), and store it for subsequent usage.
'
' 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.BaseLib.Security.Cryptography.PkiCertificates
Imports OpcLabs.EasyOpc.UA
Imports OpcLabs.EasyOpc.UA.Application
Imports OpcLabs.EasyOpc.UA.Application.Extensions
Imports OpcLabs.EasyOpc.UA.Extensions
Imports OpcLabs.EasyOpc.UA.OperationModel

Namespace Application._IEasyUAClientServerApplication
    Partial Friend Class ObtainNewCertificate
        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)

            ' Obtain a new application certificate from the certificate manager (GDS), and store it for subsequent usage.
            Dim certificate As IPkiCertificate
            Try
                certificate = application.ObtainNewCertificate(gdsEndpointDescriptor)
            Catch uaException As UAException
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException.Message)
                Exit Sub
            End Try

            ' Display results
            Console.WriteLine("Certificate: {0}", certificate)
        End Sub
    End Class
End Namespace
// Shows how to obtain a new application certificate from the certificate manager (GDS),
// and store it for subsequent usage.
//
// 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 ObtainNewCertificate.Main;
var
  Application: TEasyUAApplication;
  ApplicationElement: _UAApplicationElement;
  Certificate: _PkiCertificate;
  GdsEndpointDescriptor: _UAEndpointDescriptor;
  Arguments: _UAObtainCertificateArguments;
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.
  ApplicationElement := Application.GetApplicationElement;
  WriteLn('Application URI string: ', Application.GetApplicationElement.ApplicationUriString);

  // Obtain a new application certificate from the certificate manager (GDS), and store it for subsequent usage.
  Arguments := CoUAObtainCertificateArguments.Create;
  Arguments.Parameters.GdsEndpointDescriptor := GdsEndpointDescriptor;

  try
    Certificate := Application.ObtainNewCertificate(Arguments);
  except
    on E: EOleException do
    begin
      WriteLn(Format('*** Failure: %s', [E.GetBaseException.Message]));
    end;
  end;

  // Display results
  WriteLn('Certificate: ', (Certificate as _PKICertificate).ToString);
end;
// Shows how to obtain a new application certificate from the certificate manager (GDS),
// and store it for subsequent usage.
//
// 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.
$ApplicationElement = $Application->GetApplicationElement;
printf("Application URI string: %s\n", $Application->GetApplicationElement->ApplicationUriString);

// Obtain a new application certificate from the certificate manager (GDS), and store it for subsequent usage.
$Arguments = new COM("OpcLabs.EasyOpc.UA.Application.UAObtainCertificateArguments");
$Arguments->Parameters->GdsEndpointDescriptor = $GdsEndpointDescriptor;

try
{
    $Certificate = $Application->ObtainNewCertificate($Arguments);
}
catch (com_exception $e)
{
    printf("*** Failure: %s\n", $e->getMessage());
    exit();
}

// Display results
printf("Certificate: %s\n", $Certificate);
REM Shows how to obtain a new application certificate from the certificate manager (GDS),
REM and store it for subsequent usage.
REM
REM Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
REM OPC client and subscriber examples in Visual Basic on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-VB .
REM Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
REM a commercial license in order to use Online Forums, and we reply to every post.

Private Sub IEasyUAClientServerApplication_ObtainNewCertificate_Main_Command_Click()
    OutputText = ""
    
    ' Define which GDS we will work with.
    Dim gdsEndpointDescriptor As New 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
    Dim Application As New EasyUAApplication
    
    ' Display which application we are about to work with.
    OutputText = OutputText & "Application URI string: " & Application.GetApplicationElement.applicationUriString & vbCrLf

    ' Obtain a new application certificate from the certificate manager (GDS), and store it for subsequent usage.
    Dim arguments As New UAObtainCertificateArguments
    Set arguments.Parameters.gdsEndpointDescriptor = gdsEndpointDescriptor
    
    On Error Resume Next
    Dim certificate As PkiCertificate
    Set certificate = Application.ObtainNewCertificate(arguments)
    If Err.Number <> 0 Then
        OutputText = OutputText & "*** Failure: " & Err.Source & ": " & Err.Description & vbCrLf
        Exit Sub
    End If
    On Error GoTo 0

    ' Display results
    OutputText = OutputText & "Certificate: " & certificate & vbCrLf
End Sub
Rem Shows how to obtain a new application certificate from the certificate manager (GDS), and store it for subsequent usage.
Rem
Rem Find all latest examples here: https://opclabs.doc-that.com/files/onlinedocs/OPCLabs-OpcStudio/Latest/examples.html .
Rem OPC client and subscriber examples in VBScript on GitHub: https://github.com/OPCLabs/Examples-QuickOPC-VBScript .
Rem Missing some example? Ask us for it on our Online Forums, https://www.opclabs.com/forum/index ! You do not have to own
Rem a commercial license in order to use Online Forums, and we reply to every post.

Option Explicit

' Define which GDS we will work with.
Dim GdsEndpointDescriptor: Set GdsEndpointDescriptor = CreateObject("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.
Dim Application: Set Application = CreateObject("OpcLabs.EasyOpc.UA.Application.EasyUAApplication")

' Display which application we are about to work with.
Dim ApplicationElement: Set ApplicationElement = Application.GetApplicationElement
WScript.Echo "Application URI string: " & Application.GetApplicationElement.ApplicationUriString

Rem Obtain a new application certificate from the certificate manager (GDS), and store it for subsequent usage.
Dim Arguments: Set Arguments = CreateObject("OpcLabs.EasyOpc.UA.Application.UAObtainCertificateArguments")
Set Arguments.Parameters.GdsEndpointDescriptor = GdsEndpointDescriptor
On Error Resume Next
Dim Certificate: Set Certificate = Application.ObtainNewCertificate(Arguments)
If Err.Number <> 0 Then
    WScript.Echo "*** Failure: " & Err.Source & ": " & Err.Description
    WScript.Quit
End If
On Error Goto 0

' Display results
WScript.Echo "Certificate: " & Certificate
# Shows how to obtain a new application certificate from the certificate manager (GDS), and store it for subsequent
# usage.
#
# 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='')

# Obtain a new application certificate from the certificate manager (GDS), and store it for subsequent usage.
try:
    print('Obtaining new certificate...')
    certificate = IEasyUAClientServerApplicationExtension.ObtainNewCertificate(application, gdsEndpointDescriptor)
except UAException as uaException:
    print('*** Failure: ' + uaException.GetBaseException().Message)
    exit()

# Display results.
print('Certificate: ', certificate, 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

See Also