Method queueHandoff

maintnotifications/handoff_worker.go:267–327

queueHandoff queues a handoff request for processing if err is returned, connection will be removed from pool

(conn *pool.Conn)

// queueHandoff queues a handoff request for processing
// if err is returned, connection will be removed from pool
func (hwm *handoffWorkerManager) queueHandoff(conn *pool.Conn) error {
	// Get handoff info atomically to prevent race conditions
	shouldHandoff, endpoint, seqID := conn.GetHandoffInfo()

	// on retries the connection will not be marked for handoff, but it will have retries > 0
	// if shouldHandoff is false and retries is 0, then we are not retrying and not do a handoff
	if !shouldHandoff && conn.HandoffRetries() == 0 {
		if internal.LogLevel.InfoOrAbove() {
			internal.Logger.Printf(context.Background(), logs.ConnectionNotMarkedForHandoff(conn.GetID()))
		}
		return errors.New(logs.ConnectionNotMarkedForHandoffError(conn.GetID()))
	}

	// Create handoff request with atomically retrieved data
	request := HandoffRequest{
		Conn:     conn,
		ConnID:   conn.GetID(),
		Endpoint: endpoint,
		SeqID:    seqID,
		Pool:     hwm.poolHook.pool, // Include pool for connection removal on failure
	}

	select {
	// priority to shutdown
	case <-hwm.shutdown:
		return ErrShutdown
	default:
		select {
		case <-hwm.shutdown:
			return ErrShutdown
		case hwm.handoffQueue <- request:
			// Store in pending map
			hwm.pending.Store(request.ConnID, request.SeqID)
			// Ensure we have a worker to process this request
			hwm.ensureWorkerAvailable()
			return nil
		default:
			select {
			case <-hwm.shutdown:
				return ErrShutdown
			case hwm.handoffQueue <- request:
				// Store in pending map
				hwm.pending.Store(request.ConnID, request.SeqID)
				// Ensure we have a worker to process this request
				hwm.ensureWorkerAvailable()
				return nil
			case <-time.After(100 * time.Millisecond): // give workers a chance to process
				// Queue is full - log and attempt scaling
				queueLen := len(hwm.handoffQueue)
				queueCap := cap(hwm.handoffQueue)
				if internal.LogLevel.WarnOrAbove() {
					internal.Logger.Printf(context.Background(), logs.HandoffQueueFull(queueLen, queueCap))
				}
			}
		}
	}

	// Ensure we have workers available to handle the load