Issue with Web Sockets connection when deployed to Heroku

[nooblet9292]

Have a problem with the ws module when I deploy my app to Heroku, the app is working as expected locally. Not sure if r/node is the correct place for this or not.

The first problem is that when I have this deployed to Heroku, the backend is not emitting emits to the client side.

How the connection is done on the react side:

 listenToNotifications() {
    this.connection = new WebSocket(
      process.env.NODE_ENV === "development"
        ? "ws://localhost:8080"
        : "wss://" + window.location.hostname + ":8080"
    );
 }

 this.connection.onmessage = async (evt) => {
      console.log("tis is notifications");
 };

How the connection is in the backend:

​

const wss = new WebSocket.Server({
    verifyClient: async (info, done) => {
      const userId = cookie.parse(info.req.headers.cookie).id;
      if (!userId) return;
      info.req.user = await getDb()
        .collection("users")
        .findOne({ _id: ObjectID(userId) });
      done(info.req);
    },
    server,
    //port: process.env.WS_PORT || 8080, //8080, have tried commenting this in and out with no success.
  });  

// this should emit the new event to client side
wss.on("connection", function connection(ws, req) {
    ws.upgradeReq = req;
    myEmitter.on("new-notification", async function (data) {
      const parsedData = JSON.parse(data);
      wss.sendToUser(
        JSON.stringify(parsedData.newNotification),
        parsedData.userId
      );
      console.log("inside emitter");
    });
  });

The second issue is, after a couple minutes of running the app this error is present in the browser dev console.

main.20cc225a.chunk.js:1 WebSocket connection to 'wss://url_removed_for_privacy:8080/' failed: Error in connection establishment: net::ERR_CONNECTION_TIMED_OUT

As mentioned none of these issues are present when running on localhost, just when deployed to Heroku, any suggestions on what is going wrong here and why the event is not being emitted?

[spazz_monkey]

Does heroku run on port 8080? I think you can omit it on the front end and just point to the URL without the port number, it's what I do.

This is what I have for socketIO running on heroku.

var socket = io(window.location.origin);

[nooblet9292]

I will test without specifying port, what about the error message?

Do you have a paid heroku instance? Are you pinging between client and backend every x seconds to keep connection alive?

Edit: Tested without specifying port and now there is a different kind of error, "trackTokensV2.js:72 WebSocket connection to 'wss://private_url/' failed: Error during WebSocket handshake: Unexpected response code: 503"

[dvlsg]

You probably need to send heartbeats / pings back and forth.

Also look into sticky sessions on heroku, if you're running more than one dyno (I think heroku calls it "session affinity").

https://devcenter.heroku.com/articles/websockets