server_with_da_variables.js

/* global console, require */
var opcua = require("node-opcua");

const server = new opcua.OPCUAServer({
    port: 4334 // the port of the listening socket of the server
});

function post_initialize() {

    const addressSpace = server.engine.addressSpace;
    const namespace = addressSpace.getOwnNamespace();

    const myDevice = namespace.addObject({
        organizedBy: addressSpace.rootFolder.objects,
        browseName: "MyDevice"
    });
    
    
    const fakeValue = 1;

    const analogItem = namespace.addAnalogDataItem({
    
          componentOf: myDevice,
    
          browseName: "TemperatureSensor",
    
          definition: "(tempA -25) + tempB",
          valuePrecision: 0.5,
          engineeringUnitsRange: { low: 100 , high: 200},
          instrumentRange: { low: -100 , high: +200},
          engineeringUnits: opcua.standardUnits.degree_celsius,
          dataType: "Double",
    
          value: { get: function(){return new opcua.Variant({dataType: opcua.DataType.Double , value: fakeValue}); } }
    });

} 

server.initialize(post_initialize);

server.start(function() {
    console.log("Server is now listening ... ( press CTRL+C to stop)");
});