OPC UA.NET custom Node Manager creating

Question

I'm trying to use UA-.NETStandardLibrary by OPC Foundation to create my own OPC UA Server that will maintain some variables. I've created a server class inherited from StandardServer and node manager inherited from CustomNodeManager2. There were some node managers in their examples, I removed them and add my own one. The server starts normally and doesn't contain any nodes except from standard ones, as planned. So, my problem is how to create my own variable node from code (not from xml, as in examples) and be able update its value on demand.

For example, I want to add a folder with couple of nodes inside.

Does anyone have a code snippet which demonstrates how to do it? I don't want anybody write it for me, I will appreciate only if you just tell me about a right way to make it.

Thanks a lot.

Answer 1

I am pretty sure the snippets you are looking for are included. Here is my testing code and I am 100% positive, I didn't write the second piece of code. Anyway, if this helps you...

                {
                    var ticker_seq = createVariable(myFolder, "MyFolder/Ticker", "Ticker", BuiltInType.UInt64, ValueRanks.Scalar);
                    variables.Add(ticker_seq);

                    subscriptions.Add(clock.Ticker.Subscribe(val =>
                    {
                        lock (Lock)
                        {
                            ticker_seq.Value = val;
                            ticker_seq.Timestamp = DateTime.UtcNow;
                            ticker_seq.ClearChangeMasks(SystemContext, false);
                        }
                    }));
                }

and creation

    private BaseDataVariableState createVariable(NodeState parent, string path, string name, NodeId dataType, int valueRank)
    {
        BaseDataVariableState variable = new BaseDataVariableState(parent);

        variable.SymbolicName = name;
        variable.ReferenceTypeId = ReferenceTypes.Organizes;
        variable.TypeDefinitionId = VariableTypeIds.BaseDataVariableType;
        variable.NodeId = new NodeId(path, NamespaceIndex);
        variable.BrowseName = new QualifiedName(path, NamespaceIndex);
        variable.DisplayName = new LocalizedText("en", name);
        variable.WriteMask = AttributeWriteMask.DisplayName | AttributeWriteMask.Description;
        variable.UserWriteMask = AttributeWriteMask.DisplayName | AttributeWriteMask.Description;
        variable.DataType = dataType;
        variable.ValueRank = valueRank;
        variable.AccessLevel = AccessLevels.CurrentReadOrWrite;
        variable.UserAccessLevel = AccessLevels.CurrentReadOrWrite;
        variable.Historizing = false;
        variable.Value = 0;
        variable.StatusCode = StatusCodes.Good;
        variable.Timestamp = DateTime.UtcNow;

        if (parent != null)
        {
            parent.AddChild(variable);
        }

        return variable;
    }

creating the folder:

    private FolderState CreateFolder(NodeState parent, string path, string name)
    {
        FolderState folder = new FolderState(parent);

        folder.SymbolicName = name;
        folder.ReferenceTypeId = ReferenceTypes.Organizes;
        folder.TypeDefinitionId = ObjectTypeIds.FolderType;
        folder.NodeId = new NodeId(path, NamespaceIndex);
        folder.BrowseName = new QualifiedName(path, NamespaceIndex);
        folder.DisplayName = new LocalizedText("en", name);
        folder.WriteMask = AttributeWriteMask.None;
        folder.UserWriteMask = AttributeWriteMask.None;
        folder.EventNotifier = EventNotifiers.None;

        if (parent != null)
        {
            parent.AddChild(folder);
        }

        return folder;
    }