Long Polling Pattern and Reconnection Logic
Implement long polling with exponential backoff and automatic reconnection using useEffect and AbortController.
Long Polling Flow
Long polling works in a cycle: the client sends an HTTP request, the server holds the connection open until new data is available (or a timeout occurs, typically 30-60 seconds), the server responds with the data, and the client immediately fires another request. This creates a near-continuous connection with server-push characteristics.
Implementing Long Polling in useEffect
Long polling in React uses an async recursive function inside useEffect. The function makes a fetch request, processes the response, and then calls itself again. An AbortController signal stops the recursion when the component unmounts. The function loops as long as the component is mounted and no abort has been signaled.
All lessons in this course
- SSE vs WebSockets vs Polling Comparison
- Consuming SSE Streams in React with EventSource
- Long Polling Pattern and Reconnection Logic
- Building a Real-Time Notification Feed