Method lastSequence

db/sequence_allocator.go:155–169

Retrieves the last allocated sequence. If there hasn't been an allocation yet by this node, retrieves the value of the _sync:seq counter from the bucket by doing an incr(0)

(ctx context.Context)

// Retrieves the last allocated sequence.  If there hasn't been an allocation yet by this node,
// retrieves the value of the _sync:seq counter from the bucket by doing an incr(0)
func (s *sequenceAllocator) lastSequence(ctx context.Context) (uint64, error) {
	s.mutex.Lock()
	lastSeq := s.last
	s.mutex.Unlock()

	if lastSeq > 0 {
		return lastSeq, nil
	}
	s.dbStats.SequenceGetCount.Add(1)
	last, err := s.getSequence()
	if err != nil {
		return 0, fmt.Errorf("Couldn't get sequence from bucket: %w", err)
	}
	return last, err
}

// Returns the next available sequence.
// If previously reserved sequences are available (s.last < s.max), returns one