chash

type CHash interface {
	// AddMembers adds one or more members to the cluster
	// May return ErrInvalidCapacity if member capacity less or equal 0
	// May return ErrMemberExists if member was added before
	AddMembers(members ...Member) error
	// RemoveMembers removes members with given ids
	RemoveMembers(memberIds ...string) error
	// Reconfigure replaces all members list
	Reconfigure(members []Member) error
	// GetMembers returns list of members for given key
	// Members count will be equal replication factor or total members count (if it is less than the replication factor)
	GetMembers(key string) []Member
	// GetPartition returns partition number for given key
	GetPartition(key string) int
	// GetPartitionMembers return members by partition number
	GetPartitionMembers(partId int) ([]Member, error)
	// Distribute members by partitions
	// Must be called if you changed members' capacity
	Distribute()
	// PartitionCount returns configured partitions count
	PartitionCount() int
}

type Config struct {
	// Hasher implementation (optional), by default, will be used xxhash
	Hasher Hasher
	// PartitionCount - how many virtual partitions will be distributed by nodes, reasonable values from 100 to 10k
	PartitionCount uint64
	// ReplicationFactor - how many nodes expected for GetMembers
	ReplicationFactor int
	// Multiply Factor (optional) - this value multiplied for member capacity means how many times a member will be added to the hash ring. The default value is 2000.
	MultiplyFactor int
}

type Hasher interface {
	Sum64([]byte) uint64
}

type Member interface {
	Id() string
	Capacity() float64
}