👀 Views: 63 💬 Answers: 1 📅 Created: 2025-06-15

reactjs useEffect websockets javascript

I'm trying to configure Can someone help me understand I'm experiencing an issue where the cleanup function of my `useEffect` hook isn't being called when the component unmounts. I have a simple component that sets up a WebSocket connection, and I expected the cleanup function to close the connection when the component is removed from the DOM. However, it seems like the WebSocket remains open even after the component is unmounted, which can lead to memory leaks and unexpected behavior. Here’s a simplified version of my component: ```javascript import React, { useEffect } from 'react'; const WebSocketComponent = () => { const socket = new WebSocket('ws://example.com/socket'); useEffect(() => { socket.onopen = () => { console.log('WebSocket connected'); }; socket.onmessage = (event) => { console.log('Message from server ', event.data); }; // Cleanup function to close the WebSocket return () => { console.log('Cleaning up...'); socket.close(); }; }, []); // Empty dependency array return <div>WebSocket Component</div>; }; export default WebSocketComponent; ``` I’ve checked that the component is indeed being unmounted, but the message from the cleanup function doesn’t appear in the console, which makes me think the cleanup isn’t being triggered. I've also tried adding dependencies to the `useEffect` array, but that didn’t help. I’m using React 18.0.0 and based on the documentation, I believe this should work as expected. Any ideas on why the cleanup function might not be firing? Additionally, I’d like to know if there's a better pattern to manage WebSocket connections in React to avoid these issues in the first place. Thanks for any help! My team is using Javascript for this web app. Cheers for any assistance!