Examples - OPC Unified Architecture - Discover servers on a network, flat

.NET

// This example shows how to obtain information about OPC UA servers available on the network.
// The result is flat, i.e. each discovery URL is returned in separate element, with possible repetition of the servers.

using System;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.Discovery;
using OpcLabs.EasyOpc.UA.OperationModel;

namespace UADocExamples._EasyUAClient
{
    partial class DiscoverNetworkServers
    {
        public static void Main1()
        {
            // Instantiate the client object.
            var client = new EasyUAClient();

            // Obtain collection of application elements.
            UADiscoveryElementCollection discoveryElementCollection;
            try
            {
                discoveryElementCollection = client.DiscoverNetworkServers("opcua.demo-this.com");
            }
            catch (UAException uaException)
            {
                Console.WriteLine($"*** Failure: {uaException.GetBaseException().Message}");
                return;
            }

            // Display results.
            foreach (UADiscoveryElement discoveryElement in discoveryElementCollection)
            {
                Console.WriteLine();
                Console.WriteLine($"Server name: {discoveryElement.ServerName}");
                Console.WriteLine($"Discovery URI string: {discoveryElement.DiscoveryUriString}");
                Console.WriteLine($"Server capabilities: {discoveryElement.ServerCapabilities}");
                Console.WriteLine($"Application URI string: {discoveryElement.ApplicationUriString}");
                Console.WriteLine($"Product URI string: {discoveryElement.ProductUriString}");
            }
        }
    }
}

# This example shows how to obtain information about OPC UA servers available on the network.
# The result is flat, i.e. each discovery URL is returned in separate element, with possible repetition of the servers.

#requires -Version 5.1
using namespace OpcLabs.EasyOpc.UA
using namespace OpcLabs.EasyOpc.UA.Discovery
using namespace OpcLabs.EasyOpc.UA.OperationModel

# The path below assumes that the current directory is [ProductDir]/Examples-NET/PowerShell/Windows .
Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcUA.dll"
Add-Type -Path "../../../Components/Opclabs.QuickOpc/net472/OpcLabs.EasyOpcUAComponents.dll"

# Instantiate the client object.
$client = New-Object EasyUAClient

# Obtain collection of application elements.
try {
    $discoveryElementCollection = [IEasyUAClientExtension]::DiscoverNetworkServers($client, "opcua.demo-this.com")
}
catch [UAException] {
    Write-Host "*** Failure: $($PSItem.Exception.GetBaseException().Message)"
    return
}

# Display results.
foreach ($discoveryElement in $discoveryElementCollection) {
    Write-Host
    Write-Host "Server name: $($discoveryElement.ServerName)"
    Write-Host "Discovery URI string: $($discoveryElement.DiscoveryUriString)"
    Write-Host "Server capabilities: $($discoveryElement.ServerCapabilities)"
    Write-Host "Application URI string: $($discoveryElement.ApplicationUriString)"
    Write-Host "Product URI string: $($discoveryElement.ProductUriString)"
}

# This example shows how to obtain information about OPC UA servers available on the network.
# The result is flat, i.e. each discovery URL is returned in separate element, with possible repetition of the servers.

# 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.Discovery import *
from OpcLabs.EasyOpc.UA.OperationModel import *


# Instantiate the client object.
client = EasyUAClient()

# Obtain collection of application elements.
try:
    discoveryElementCollection = IEasyUAClientExtension.DiscoverNetworkServers(client, 'opcua.demo-this.com')
except UAException as uaException:
    print('*** Failure: ' + uaException.GetBaseException().Message)
    exit()

# Display results.
for discoveryElement in discoveryElementCollection:
    print()
    print('Server name: ', discoveryElement.ServerName, sep='')
    print('Discovery URI string: ', discoveryElement.DiscoveryUriString, sep='')
    print('Server capabilities: ', discoveryElement.ServerCapabilities, sep='')
    print('Application URI string: ', discoveryElement.ApplicationUriString, sep='')
    print('Product URI string: ', discoveryElement.ProductUriString, sep='')

print()
print('Finished.')

' This example shows how to obtain information about OPC UA servers available on the network.
' The result is flat, i.e. each discovery URL is returned in separate element, with possible repetition of the servers.

Imports OpcLabs.EasyOpc.UA
Imports OpcLabs.EasyOpc.UA.Discovery
Imports OpcLabs.EasyOpc.UA.OperationModel

Namespace _EasyUAClient
    Partial Friend Class DiscoverNetworkServers
        Public Shared Sub Main1()
            ' Instantiate the client object
            Dim client = New EasyUAClient()

            ' Obtain collection of application elements
            Dim discoveryElementCollection As UADiscoveryElementCollection
            Try
                discoveryElementCollection = client.DiscoverNetworkServers("opcua.demo-this.com")
            Catch uaException As UAException
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException.Message)
                Exit Sub
            End Try

            ' Display results
            For Each discoveryElement As UADiscoveryElement In discoveryElementCollection
                Console.WriteLine()
                Console.WriteLine("Server name: {0}", discoveryElement.ServerName)
                Console.WriteLine("Discovery URI string: {0}", discoveryElement.DiscoveryUriString)
                Console.WriteLine("Server capabilities: {0}", discoveryElement.ServerCapabilities)
                Console.WriteLine("Application URI string: {0}", discoveryElement.ApplicationUriString)
                Console.WriteLine("Product URI string: {0}", discoveryElement.ProductUriString)
            Next discoveryElement
        End Sub
    End Class
End Namespace

COM

// This example shows how to obtain information about OPC UA servers available on the network.

class procedure DiscoverNetworkServers.Main;
var
  Client: OpcLabs_EasyOpcUA_TLB._EasyUAClient;
  Count: Cardinal;
  Element: OleVariant;
  DiscoveryElement: _UADiscoveryElement;
  DiscoveryElementEnumerator: IEnumVariant;
  DiscoveryElements: _UADiscoveryElementCollection;
begin
  // Instantiate the client object
  Client := CoEasyUAClient.Create;

  // Obtain collection of application elements
  try
    DiscoveryElements := Client.DiscoverNetworkServers(Unassigned, 'opcua.demo-this.com');
  except
    on E: EOleException do
    begin
      WriteLn(Format('*** Failure: %s', [E.GetBaseException.Message]));
      Exit;
    end;
  end;

  // Display results
  DiscoveryElementEnumerator := DiscoveryElements.GetEnumerator;
  while (DiscoveryElementEnumerator.Next(1, Element, Count) = S_OK) do
  begin
    DiscoveryElement := IUnknown(Element) as _UADiscoveryElement;
    WriteLn;
    WriteLn('Server name: ', DiscoveryElement.ServerName);
    WriteLn('Discovery URI string: ', DiscoveryElement.DiscoveryUriString);
    WriteLn('Server capabilities: ', DiscoveryElement.ServerCapabilities.ToString);
  end;
end;

// This example shows how to obtain information about OPC UA servers available on the network.

#include "stdafx.h"    // Includes "QuickOpc.h", and other commonly used files
#include "DiscoverNetworkServers.h"

namespace _EasyUAClient
{
    void DiscoverNetworkServers::Main()
    {
        // Initialize the COM library
        CoInitializeEx(NULL, COINIT_MULTITHREADED);
        {
            // Instantiate the client object
            _EasyUAClientPtr ClientPtr(__uuidof(EasyUAClient));

            _StringCollectionPtr ServerElementFilterPtr(__uuidof(StringCollection));
            _variant_t vServerElementFilter(ServerElementFilterPtr.GetInterfacePtr());

            // Obtain collection of application elements
            _UADiscoveryElementCollectionPtr DiscoveryElementsPtr = 
                ClientPtr->DiscoverNetworkServers(vServerElementFilter, L"opcua.demo-this.com");
    
            // Display results
            IEnumVARIANTPtr EnumDiscoveryElementPtr = DiscoveryElementsPtr->GetEnumerator();
            _variant_t vDiscoveryElement;
            while (EnumDiscoveryElementPtr->Next(1, &vDiscoveryElement, NULL) == S_OK)
            {
                _UADiscoveryElementPtr DiscoveryElementPtr(vDiscoveryElement);
                _tprintf(_T("\n"));
                _tprintf(_T("Application type: %d\n"), DiscoveryElementPtr->ApplicationType);
                _tprintf(_T("Server name: %s\n"), (LPCTSTR)CW2CT(DiscoveryElementPtr->ServerName));
                _tprintf(_T("Discovery URI string: %s\n"), (LPCTSTR)CW2CT(DiscoveryElementPtr->DiscoveryUriString));
                _tprintf(_T("Server capabilities: "));
                IEnumVARIANTPtr EnumServerCapabilityPtr = DiscoveryElementPtr->ServerCapabilities->GetEnumerator();
                _variant_t vServerCapability = NULL;
                while (EnumServerCapabilityPtr->Next(1, &vServerCapability, NULL) == S_OK)
                    _tprintf(_T("%s "), (LPCTSTR)CW2CT(_bstr_t(vServerCapability)));
                _tprintf(_T("\n"));
                vDiscoveryElement.Clear();
            }
        }
         // Release all interface pointers BEFORE calling CoUninitialize()
        CoUninitialize();
    }
}

Rem This example shows how to obtain information about OPC UA servers available on the network.

Public Sub DiscoverNetworkServers_Main_Command_Click()
    OutputText = ""

    ' Instantiate the client object
    Dim Client As New EasyUAClient

    ' Obtain collection of application elements
    On Error Resume Next
    Dim DiscoveryElementCollection As UADiscoveryElementCollection
    Set DiscoveryElementCollection = Client.DiscoverNetworkServers(Nothing, "opcua.demo-this.com")
    If Err.Number <> 0 Then
        OutputText = OutputText & "*** Failure: " & Err.Source & ": " & Err.Description & vbCrLf
        Exit Sub
    End If
    On Error GoTo 0
    
    ' Display results
    Dim DiscoveryElement As UADiscoveryElement: For Each DiscoveryElement In DiscoveryElementCollection
        OutputText = OutputText & vbCrLf
        OutputText = OutputText & "Server name: " & DiscoveryElement.ServerName & vbCrLf
        OutputText = OutputText & "Discovery URI string: " & DiscoveryElement.DiscoveryUriString & vbCrLf
        OutputText = OutputText & "Server capabilities: " & DiscoveryElement.serverCapabilities.ToString & vbCrLf
    Next
End Sub

Rem This example shows how to obtain information about OPC UA servers available on the network.

Option Explicit

' Instantiate the client object
Dim Client: Set Client = CreateObject("OpcLabs.EasyOpc.UA.EasyUAClient")

' Obtain collection of application elements
On Error Resume Next
Dim DiscoveryElementCollection: Set DiscoveryElementCollection = _
    Client.DiscoverNetworkServers(Nothing, "opcua.demo-this.com")
If Err.Number <> 0 Then
    WScript.Echo "*** Failure: " & Err.Source & ": " & Err.Description
    WScript.Quit
End If
On Error Goto 0

' Display results
Dim DiscoveryElement: For Each DiscoveryElement In DiscoveryElementCollection
    WScript.Echo
    WScript.Echo "Server name: " & DiscoveryElement.ServerName
    WScript.Echo "Discovery URI string: " & DiscoveryElement.DiscoveryUriString
    Dim s: s = ""
    Dim serverCapability: For Each serverCapability In DiscoveryElement.ServerCapabilities
        s = s & serverCapability & " "
    Next
    WScript.Echo "Server capabilities: " & s
Next

Conceptual

OPC UA Network Discovery