Examples - OPC UA File Transfer - Write full file contents

The example below shows how to write the full contents of an OPC UA file at once, using the file transfer client.

.NET

C#
VB.NET

// Shows how to write the full contents of an OPC UA file at once, 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 System.IO;
using System.Text;
using OpcLabs.EasyOpc.UA;
using OpcLabs.EasyOpc.UA.FileTransfer;
using OpcLabs.EasyOpc.UA.IO.Extensions;

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

            // A node that represents an instance of OPC UA FileType object.
            UANodeDescriptor fileNodeDescriptor = "nsu=http://www.unifiedautomation.com/DemoServer/ ;s=Demo.Files.TextFile";
            
            // Instantiate the file transfer client object
            var fileTransferClient = new EasyUAFileTransferClient();

            // Write all contents into a specified file node.
            byte[] bytes = Encoding.UTF8.GetBytes("TEXT FROM FILE TRANSFER CLIENT EXAMPLE. Demonstrates writing the whole contents of a file at once.");
            try
            {
                Console.WriteLine("Writing the whole file...");
                fileTransferClient.WriteAllBytes(endpointDescriptor, fileNodeDescriptor, bytes);

                // Due to an issue in the server, the file might not be readable now, without server restart.
                //Console.WriteLine("Reading the data back...");
                //byte[] data = fileTransferClient.ReadAllFileBytes(endpointDescriptor, fileNodeDescriptor);
                //Console.WriteLine(Encoding.UTF8.GetString(data));
            }
            // Beware that WriteAllFileBytes throws IOException and not UAException.
            catch (IOException ioException)
            {
                Console.WriteLine("*** Failure: {0}", ioException.GetBaseException().Message);
                return;
            }

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

' Shows how to write the full contents of an OPC UA file at once, 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 System.IO
Imports System.Text
Imports OpcLabs.EasyOpc.UA
Imports OpcLabs.EasyOpc.UA.FileTransfer
Imports OpcLabs.EasyOpc.UA.IO.Extensions

Namespace FileTransfer._EasyUAFileTransferClient

    Friend Class WriteAllBytes

        Public Shared Sub Main1()

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

            ' A node that represents an instance of OPC UA FileType object.
            Dim fileNodeDescriptor As UANodeDescriptor = "nsu=http://www.unifiedautomation.com/DemoServer/ ;s=Demo.Files.TextFile"

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

            ' Write all contents into a specified file node.
            Dim bytes As Byte() = Encoding.UTF8.GetBytes("TEXT FROM FILE TRANSFER CLIENT EXAMPLE. Demonstrates writing the whole contents of a file at once.")
            Try
                Console.WriteLine("Writing the whole file...")
                fileTransferClient.WriteAllBytes(endpointDescriptor, fileNodeDescriptor, bytes)

                ' Due to an issue in the server, the file might Not be readable now, without server restart.
                'Console.WriteLine("Reading the data back...")
                'Dim data As Byte() = fileTransferClient.ReadAllFileBytes(endpointDescriptor, fileNodeDescriptor)
                'Console.WriteLine(Encoding.UTF8.GetString(data))

                ' Beware that WriteAllFileBytes throws IOException And Not UAException.
            Catch ioException As IOException
                Console.WriteLine("*** Failure: {0}", ioException.GetBaseException.Message)
                Exit Sub
            End Try

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

Python

Python (.NET)

# Shows how to write the full contents of an OPC UA file at once, 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 .NET namespaces.
from System.Text import *
from OpcLabs.EasyOpc.UA import *
from OpcLabs.EasyOpc.UA.Extensions import *
from OpcLabs.EasyOpc.UA.FileTransfer import *
from OpcLabs.EasyOpc.UA.IO.Extensions import *
from OpcLabs.EasyOpc.UA.Navigation import *


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

# A node that represents an instance of OPC UA FileType object.
fileNodeDescriptor = UANodeDescriptor('nsu=http://www.unifiedautomation.com/DemoServer/ ;s=Demo.Files.TextFile')

# 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)

# Write all contents into a specified file node.
bytes = Encoding.UTF8.GetBytes('TEXT FROM FILE TRANSFER CLIENT EXAMPLE. Demonstrates writing the whole contents of a '
                               'file at once.')
try:
    print('Writing the whole file...')
    IEasyUAFileTransferExtension2.WriteAllBytes(fileTransferClient,
                                                endpointDescriptor,
                                                UANamedNodeDescriptor(fileNodeDescriptor),
                                                bytes)

    # Due to an issue in the server, the file might not be readable now, without server restart.
    print('Reading the data back...')
    data = IEasyUAFileTransferExtension2.ReadAllBytes(fileTransferClient,
                                                       endpointDescriptor,
                                                       UANamedNodeDescriptor(fileNodeDescriptor))
    print(Encoding.UTF8.GetString(data))

# Beware that ReadAllFileBytes throws IOException and not UAException.
except IOException as ioException:
    print('*** Failure: ' + ioException.GetBaseException().Message)
    exit()

print()
print('Finished.')

Examples - Client OPC UA File Providers

Examples - OPC UA File Providers - Write full file contents

Concepts

OPC UA File Transfer Client