Method GetNeighborsEx

consistent/consistent.go:304–352

GetNeighborsEx returns the N closest distinct nodes to the name input in the circle.

(name string, n int, roles proto.ServerRoles)

// GetNeighborsEx returns the N closest distinct nodes to the name input in the circle.
func (c *Consistent) GetNeighborsEx(name string, n int, roles proto.ServerRoles) ([]proto.Node, error) {
	c.RLock()
	defer c.RUnlock()
	c.cacheLock.RLock()
	defer c.cacheLock.RUnlock()

	if len(c.circle) == 0 {
		return nil, ErrEmptyCircle
	}

	count := len(c.sortedHashes) / c.NumberOfReplicas
	if count < n {
		n = count
	}

	var (
		key   = hashKey(name)
		i     = c.search(key)
		start = i
		res   = make([]proto.Node, 0, n)
		elem  = *c.circle[c.sortedHashes[i]]
	)
	var noFilter = roles == nil || len(roles) == 0

	if noFilter || roles.Contains(elem.Role) {
		res = append(res, elem)
	}

	if noFilter && len(res) == n {
		return res, nil
	}

	for i = start + 1; i != start; i++ {
		if i >= len(c.sortedHashes) {
			i = 0
		}
		elem = *c.circle[c.sortedHashes[i]]
		if noFilter || roles.Contains(elem.Role) {
			if !sliceContainsMember(res, elem) {
				res = append(res, elem)
			}
		}
		if len(res) == n {
			break
		}
	}

	return res, nil
}

// GetNeighbors returns the N closest distinct nodes to the name input in the circle.
func (c *Consistent) GetNeighbors(name string, n int) ([]proto.Node, error) {