Websocket not sending patch

CarlosR

Hi,

I'm trying to subscribe via websocket to the object model using a node.js client.

let objectModel = null;
  wsClientDuet.on("connectFailed", function (error) {
    console.log("Connect Error");
  });
  wsClientDuet.on("connect", (conn) => {
    connectionDuet = conn;
    console.log("Connected to Duet WebSocket Server");
    connectionDuet.on("error", function (error) {
      console.log("Connection Error");
    });
    connectionDuet.on("close", function () {
      console.log("Connection to Duet is closed");
    });
    connectionDuet.on("message", function (message) {
      console.log(message.utf8Data);
      if (message.utf8Data === "PONG\n") {
        return;
      }
      if (objectModel === null) {
        objectModel = message.utf8Data;
        console.log("Object model received");
        return;
      }
      let ack = "OK\n";
      connectionDuet.sendUTF(ack);
    });
  });
  setInterval(async () => {
    if (connectionDuet.connected) {
      let message = "PING\n";
      connectionDuet.sendUTF(message);
    }
  }, 5000);

  await wsClientDuet.connect(`url`, "");

The server is replying with PONG after the PINGS.
Also, the first object model is sent. But it seems the OK is not working since the server is not sending any patch.

Is there anything wrong in the code?

Thank you.

chrishamm

@CarlosR We also provide the @duet3d/connectors NPM package but I don't know if it works in standalone NodeJS applications. See here for the message handling in SBC mode.

CarlosR

@chrishamm Thank you so much!

It didn't work indeed in standalone nodejs. However, that was easy to fix (in case anyone is interested).

Install @duet3d/connectors, @duet3d/objectmoddel and xhr2 package:

npm install @duet3d/connectors 
npm install @duet3d/objectmodel
npm install xhr2

Import XMLHttpRequest from xhr2 package in BaseConnector.js file

const XMLHttpRequest = require("xhr2");

Import WebSocket from ws package in RestConnector.js:

const WebSocket = require('ws');

Then everything work as normal.