lb.snip.1.go

// GetNextPeer returns next active peer to take a connection
func (s *ServerPool) GetNextPeer() *Backend {
	// loop entire backends to find out an Alive backend
	next := s.NextIndex()
	l := len(s.backends) + next // start from next and move a full cycle
	for i := next; i < l; i++ {
		idx := i % len(s.backends) // take an index by modding
		if s.backends[idx].IsAlive() { // if we have an alive backend, use it and store if its not the original one
			if i != next {
				atomic.StoreUint64(&s.current, uint64(idx))
			}
			return s.backends[idx]
		}
	}
	return nil
}