nodejs – 如何使用node-opcua访问远程opc服务器？

我在github中find了一个更好的项目节点opcua，使用这个项目的简单例子可以创build一个opc服务器和客户端，并且在本地可以访问，我现在需要访问一个远程的opc服务器，提供几个参数是：IPnetworking节点（例如10.195.156.150），opc服务（例如ArchestrA FSGateway），opc组（如ArchestrA），opc TagName（例如HXi1_P201_00。Ia），我可以使用node-opcua？ 谢谢！

sample_server代码：

var opcua = require("node-opcua"); var os = require("os"); // Let's create an instance of OPCUAServer var server = new opcua.OPCUAServer({port: 4334}); var siteName = 'site01'; var var1 = {nodeId: 'ns=4;s=hook_weight', browseName: 'hook_weight', dataType: 'Double'}; var var2 = {nodeId: 'ns=4;s=rpm', browseName: 'rpm', dataType: 'Double'}; var var3 = {nodeId: 'ns=1;s=free_memory', browseName: 'free_memory', dataType: 'Double'}; function post_initialize(){ console.log("server initialized"); function construct_my_address_space(server) { server.engine.createFolder("RootFolder",{ browseName: siteName}); // emulate variable1 changing every 500 ms var variable1 = 1; setInterval(function(){ variable1 += 1; }, 1000); var1.value = { get: function(){ return new opcua.Variant({dataType: opcua.DataType.Double, value: variable1 }); } }; server.var1 = server.engine.addVariableInFolder(siteName, var1); var2.value = { get: function(){ return new opcua.Variant({dataType: opcua.DataType.Double, value: 10}); } }; server.var2 = server.engine.addVariableInFolder(siteName, var2); /** /** * returns the percentage of free memory on the running machine * @return {double} */ function available_memory() { // var value = process.memoryUsage().heapUsed / 1000000; var percentageMemUsed = os.freemem() / os.totalmem() * 100.0; return percentageMemUsed; } var3.value = { get: function(){ return new opcua.Variant({dataType: opcua.DataType.Double, value: available_memory()}); } }; server.var3 = server.engine.addVariableInFolder(siteName, var3); } construct_my_address_space(server); server.start(function() { console.log("Server is now listening ... ( press CTRL+C to stop)"); console.log("port ", server.endpoints[0].port); var endpointUrl = server.endpoints[0].endpointDescription().endpointUrl; console.log(" the primary server endpoint url is ", endpointUrl ); }); } server.initialize(post_initialize); 

sample_client代码：

 var opcua = require("node-opcua"); var async = require("async"); var client = new opcua.OPCUAClient(); var endpointUrl = "opc.tcp://" + require("os").hostname().toLowerCase() + ":4334/UA/SampleServer"; var session, subscription; async.series([ // step 1 : connect to function(callback) { client.connect(endpointUrl,function (err) { if(err) { console.log(" cannot connect to endpoint :" , endpointUrl ); } else { console.log("connected !"); } callback(err); }); }, // step 2 : createSession function(callback) { client.createSession( function(err, _session) { if(!err) { session = _session; } callback(err); }); }, // step 5: install a subscription and install a monitored item for 10 seconds function(callback) { subscription=new opcua.ClientSubscription(session,{ requestedPublishingInterval: 1000, requestedLifetimeCount: 10, requestedMaxKeepAliveCount: 2, maxNotificationsPerPublish: 10, publishingEnabled: true, priority: 10 }); subscription.on("started",function(){ console.log("subscriptionId=", subscription.subscriptionId); }).on("keepalive",function(){ console.log(); }) .on("terminated",function(){ callback(); }); setTimeout(function () { subscription.terminate(); }, 10000); // install monitored item var monitoredItem = subscription.monitor({ nodeId: opcua.resolveNodeId("ns=1;s=free_memory"), attributeId: opcua.AttributeIds.Value }, { samplingInterval: 100, discardOldest: true, queueSize: 100 }, opcua.read_service.TimestampsToReturn.Both ); console.log("-------------------------------------"); monitoredItem.on("changed", function (dataValue) { console.log(" % free mem = ", dataValue.value.value); }); }, // close session function (callback) { // _"closing session" session.close(function (err) { if (err) { console.log("session closed failed ?"); } callback(); }); } ], function(err) { if (err) { console.log(" failure ",err); } else { console.log('done!'); } client.disconnect(function(){}); }); 

Answer 1

恐怕Archestra没有OPC UA服务器，所以要从节点opcua访问它，您需要使用OPC UA网关，例如https://www.prosysopc.com/products/opc-ua-网关/ ，可以将OPC DA转换为OPC UA。