for {
		select {
		case entry, ok := <-diffCh:
			if !ok {
				return
			}
			if err := enc.Encode(entry); err != nil {
				return
			}
			if len(diffCh) == 0 {
				// Flush if nothing is queued
				w.(http.Flusher).Flush()
			}
		case <-keepAliveTicker.C:
			if len(diffCh) > 0 {
				continue
			}
			if _, err := w.Write([]byte(" ")); err != nil {
				return
			}