Examples - OPC UA File Transfer - Create and delete a directory

The example below shows how to create and delete OPC UA directories, using the file transfer client.

.NET

C#
VB.NET

// Shows how to create and delete OPC UA directories, using the file transfer client.
// Note: Consider using a higher-level abstraction, OPC UA file provider, instead.
//
// 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.Extensions;
using OpcLabs.EasyOpc.UA.FileTransfer;
using OpcLabs.EasyOpc.UA.OperationModel;

namespace UADocExamples.FileTransfer._EasyUAFileTransferClient
{
    class CreateDirectoryAndDelete
    {
        public static void Main1()
        {
            // Unified Automation .NET based demo server (UaNETServer/UaServerNET.exe)
            var endpointDescriptor = new UAEndpointDescriptor("opc.tcp://localhost:48030")
                .WithUserNameIdentity("john", "master");

            // An object that aggregates an OPC UA file system.
            UANodeDescriptor objectDescriptor = "nsu=http://www.unifiedautomation.com/DemoServer/ ;s=Demo.Files";

            // Create a random number generator - will be used for file/directory names.
            var random = new Random();
            
            // Instantiate the file transfer client object
            var fileTransferClient = new EasyUAFileTransferClient();

            // Create two directories, and one nested directory, and delete the first one.
            try
            {
                // The file system node is a root directory of the file system.
                Console.WriteLine("Getting file system...");
                UANodeDescriptor fileSystemNodeDescriptor = fileTransferClient.GetFileSystem(endpointDescriptor, objectDescriptor);

                string directoryName1 = "MyDirectory1-" + random.Next();
                Console.WriteLine($"Creating first directory, '{directoryName1}'...");
                UANodeId directoryNodeId1 = fileTransferClient.CreateDirectory(endpointDescriptor, fileSystemNodeDescriptor, directoryName1);
                Console.WriteLine($"Node Id of the first directory: {directoryNodeId1}");

                string directoryName2 = "MyDirectory2-" + random.Next();
                Console.WriteLine($"Creating second directory, '{directoryName2}'...");
                UANodeId directoryNodeId2 = fileTransferClient.CreateDirectory(endpointDescriptor, fileSystemNodeDescriptor, directoryName2);
                Console.WriteLine($"Node Id of the second directory: {directoryNodeId2}");

                string nestedDirectoryName = "MyDirectory3-" + random.Next();
                Console.WriteLine($"Creating nested directory, '{nestedDirectoryName}'...");
                // Note how directoryNodeId2 (a parent directory) is passed as the 2nd argument to the CreateDirectory method.
                UANodeId nestedDirectoryNodeId = fileTransferClient.CreateDirectory(endpointDescriptor, directoryNodeId2, nestedDirectoryName);
                Console.WriteLine($"Node Id of the nested directory: {nestedDirectoryNodeId}");

                // At this moment, the directory structure we have created looks like this:
                // * MyDirectory1
                // * MyDirectory2
                // * * MyDirectory3

                Console.WriteLine("Deleting the first directory...");
                fileTransferClient.DeleteDirectory(endpointDescriptor, fileSystemNodeDescriptor, directoryName1);
            }
            catch (UAException uaException)
            {
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException().Message);
                return;
            }

            Console.WriteLine("Finished...");
        }
    }
}

' Shows how to create and delete OPC UA directories, using the file transfer client.
' Note: Consider using a higher-level abstraction, OPC UA file provider, instead.
'
' 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.Extensions
Imports OpcLabs.EasyOpc.UA.FileTransfer
Imports OpcLabs.EasyOpc.UA.OperationModel

Namespace FileTransfer._EasyUAFileTransferClient

    Friend Class CreateDirectoryAndDelete

        Public Shared Sub Main1()

            ' Unified Automation .NET based demo server (UaNETServer/UaServerNET.exe)
            Dim endpointDescriptor As UAEndpointDescriptor =
                New UAEndpointDescriptor("opc.tcp://localhost:48030") _
                .WithUserNameIdentity("john", "master")

            ' An object that aggregates an OPC UA file system.
            Dim objectDescriptor As UANodeDescriptor = "nsu=http://www.unifiedautomation.com/DemoServer/ ;s=Demo.Files"

            ' Create a random number generator - will be used for file/directory names.
            Dim random = New Random

            ' Instantiate the file transfer client object
            Dim fileTransferClient = New EasyUAFileTransferClient

            ' Create two directories, and one nested directory, and delete the first one.
            Try
                ' The file system node is a root directory of the file system.
                Console.WriteLine("Getting file system...")
                Dim fileSystemNodeDescriptor As UANodeDescriptor = fileTransferClient.GetFileSystem(endpointDescriptor, objectDescriptor)

                Dim directoryName1 As String = "MyDirectory1-" & random.Next()
                Console.WriteLine($"Creating first directory, '{directoryName1}'...")
                Dim directoryNodeId1 As UANodeId = fileTransferClient.CreateDirectory(endpointDescriptor, fileSystemNodeDescriptor, directoryName1)
                Console.WriteLine($"Node Id of the first directory: {directoryNodeId1}")

                Dim directoryName2 As String = "MyDirectory2-" & random.Next()
                Console.WriteLine($"Creating second directory, '{directoryName2}'...")
                Dim directoryNodeId2 As UANodeId = fileTransferClient.CreateDirectory(endpointDescriptor, fileSystemNodeDescriptor, directoryName2)
                Console.WriteLine($"Node Id of the second directory: {directoryNodeId2}")

                Dim nestedDirectoryName As String = "MyDirectory3-" & random.Next()
                Console.WriteLine($"Creating nested directory, '{nestedDirectoryName}'...")
                ' Note how directoryNodeId2 (a parent directory) Is passed as the 2nd argument to the CreateDirectory method.
                Dim nestedDirectoryNodeId As UANodeId = fileTransferClient.CreateDirectory(endpointDescriptor, directoryNodeId2, nestedDirectoryName)
                Console.WriteLine($"Node Id of the nested directory: {nestedDirectoryNodeId}")

                ' At this moment, the directory structure we have created looks Like this
                ' * MyDirectory1
                ' * MyDirectory2
                ' * * MyDirectory3

                Console.WriteLine("Deleting the first directory...")
                fileTransferClient.DeleteDirectory(endpointDescriptor, fileSystemNodeDescriptor, directoryName1)
            Catch uaException As UAException
                Console.WriteLine("*** Failure: {0}", uaException.GetBaseException.Message)
                Exit Sub
            End Try

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

Python

Python (.NET)

# Shows how to create and delete OPC UA directories, using the file transfer client.
# Note: Consider using a higher-level abstraction, OPC UA file provider, instead.
#
# 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 random

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


# Unified Automation .NET based demo server (UaNETServer/UaServerNET.exe).
endpointDescriptor = UAEndpointDescriptor('opc.tcp://localhost:48030')
endpointDescriptor = UAEndpointDescriptorExtension.WithUserNameIdentity(endpointDescriptor,'john', 'master')

# An object that aggregates an OPC UA file system.
objectDescriptor = UANodeDescriptor('nsu=http://www.unifiedautomation.com/DemoServer/ ;s=Demo.Files')

# Create a random number generator - will be used for file/directory names.
random = random.Random()

# Instantiate the file transfer client object.
fileTransferClient = EasyUAFileTransferClient()

# Prevent prompt to trust the server certificate (INSECURE, used just for smooth example flow).
EasyUAClient.SharedParameters.EngineParameters.CertificateAcceptancePolicy.TrustEndpointUrlString(
    endpointDescriptor.UrlString)

# Create two directories, and one nested directory, and delete the first one.
try:
    # The file system node is a root directory of the file system.
    print('Getting file system...')
    fileSystemNodeDescriptor = IEasyUAFileTransferExtension.GetFileSystem(fileTransferClient,
                                                                          endpointDescriptor, objectDescriptor)

    directoryName1 = 'MyDirectory1-' + str(random.randint(0, 999_999_999))
    print("Creating first directory, '", directoryName1, "'...", sep='')
    directoryNodeId1 = fileTransferClient.CreateDirectory(endpointDescriptor,
                                                          fileSystemNodeDescriptor,
                                                          directoryName1)
    print('Node Id of the first directory: ', directoryNodeId1, sep='')

    directoryName2 = 'MyDirectory2-' + str(random.randint(0, 999_999_999))
    print("Creating second directory, '", directoryName2, "'...", sep='')
    directoryNodeId2 = fileTransferClient.CreateDirectory(endpointDescriptor,
                                                          fileSystemNodeDescriptor,
                                                          directoryName2)
    print('Node Id of the second directory: ', directoryNodeId1, sep='')

    nestedDirectoryName = 'MyDirectory3-' + str(random.randint(0, 999_999_999))
    print("Creating nested directory, '", nestedDirectoryName, "'...", sep='')
    # Note how directoryNodeId2 (a parent directory) is passed as the 2nd argument to the CreateDirectory method.
    nestedDirectoryNodeId = fileTransferClient.CreateDirectory(endpointDescriptor,
                                                               UANodeDescriptor(directoryNodeId2),
                                                               nestedDirectoryName)
    print('Node Id of the nested directory: ', nestedDirectoryNodeId, sep='')

    # At this moment, the directory structure we have created looks like this:
    # * MyDirectory1
    # * MyDirectory2
    # * * MyDirectory3

    print('Deleting the first directory...')
    IEasyUAFileTransferExtension.DeleteDirectory(fileTransferClient,
                                                 endpointDescriptor, fileSystemNodeDescriptor, directoryName1)

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

print()
print('Finished.')

Examples - Client OPC UA File Providers

Examples - OPC UA File Providers - Create and delete a directory

Concepts

OPC UA File Transfer Client