WebSocket Not Connecting Over HTTPS (wss://) but Works on http://localhost

[DivyaChinthala]

Hi everyone,

I'm working on a Next.js (Frontend) and Node.js (Backend) application using Socket.io for real-time updates. My WebSocket connection works fine on http://localhost, but when deployed to a production environment (https://), the connection fails.

Frontend Code
import { io } from "socket.io-client";

const socket = io("https://************.amazonaws.com", {
transports: ["websocket"],
reconnectionAttempts: 3,
});

socket.emit("join", { userId, brandId, role: roleId });
socket.on("connect", () => {
console.log("✅ Connected to WebSocket");
});

socket.on("connect_error", (error) => {
console.error("❌ WebSocket connection error:", error);
});

Backend Code
import http from "http";
import { Server, Socket } from "socket.io";

const ServerInstance: http.Server = http.createServer();
setupSocket(ServerInstance);

function setupSocket(server: http.Server) {
const io = new Server(server, {
cors: { origin: "*" }, // Allowing all origins
});

io.on("connection", (socket: Socket) => {
console.log(✅ User connected: ${socket.id});

socket.on(
  "join",
  ({ userId, brandId, role }: { userId: string; brandId: string; role: string }) => {
    socket.join(`brand-${brandId}`);
    socket.join(`role-${role}`);
    socket.join(`user-${userId}`);
    console.log(`ℹ User ${userId} joined brand-${brandId} & role-${role}`);
  }
);

socket.on("disconnect", () => {
  console.log(`❌ User disconnected: ${socket.id}`);
});

});
}

Issue:
WebSocket connects successfully on http://localhost
WebSocket fails when using https://my-websocket-server.com
Error when using npx wscat -c wss://my-websocket-server.com
Unexpected server response: 403

[darrachequesne]

Hi!

Which platform are you using for your production environment? Does it support WebSocket connections?

Reference: https://socket.io/docs/v4/reverse-proxy/

[DivyaChinthala]

I am using AWS(EC2) for production