Skip to main content

Bun home page

[Runtime

](../../../index.md)[Package Manager

](../../../pm/cli/install/index.md)[Bundler

](../../../bundler/index.md)[Test Runner

](../../../test/index.md)[Guides

](../../../guides/index.md)[Reference

](https://bun.com/reference)[Blog

](https://bun.com/blog)[Feedback

](../../../feedback/index.md)

[​

](#server-pendingrequests-and-server-pendingwebsockets)

server.pendingRequests and server.pendingWebSockets

Monitor server activity with built-in counters:

const server = Bun.serve({
  fetch(req, server) {
    return new Response(
      `Active requests: ${server.pendingRequests}\n` + `Active WebSockets: ${server.pendingWebSockets}`,
    );
  },
});

[​

](#server-subscribercount-topic)

server.subscriberCount(topic)

Get count of subscribers for a WebSocket topic:

const server = Bun.serve({
  fetch(req, server) {
    const chatUsers = server.subscriberCount("chat");
    return new Response(`${chatUsers} users in chat`);
  },
  websocket: {
    message(ws) {
      ws.subscribe("chat");
    },
  },
});

Was this page helpful?

Suggest editsRaise issue

[

Error Handling

Previous

](../error-handling/index.md)[

Fetch

Next

](../../networking/fetch/index.md)