WebSocket routes

Mochi.ws() creates WebSocket endpoints with open, message, close, and drain handlers. Bun’s pub/sub is available via ws.subscribe() and ws.publish():

"/ws/chat": Mochi.ws({
  open(ws) {
    ws.subscribe("chat");
  },
  message(ws, message) {
    ws.publish("chat", String(message));
    ws.send(String(message));
  },
  close(ws) {
    ws.unsubscribe("chat");
  },
}),

An optional upgrade handler can validate the connection and attach user data:

Mochi.ws<{ userId: string }>({
  upgrade(req) {
    const userId = req.headers.get('x-user-id');
    if (!userId) return false; // reject
    return { userId }; // attached to ws.data.user
  },
  message(ws, msg) {
    console.log(ws.data.user.userId, msg);
  },
});