node

Documentation

Overview

Package node provides node selector for liaison.

Index

• Variables
• type Selector
  • func NewMaglevSelector() Selector
  • func NewPickFirstSelector() (Selector, error)
  • func NewRoundRobinSelector(schemaRegistry metadata.Repo) Selector

Variables

var (

	// ErrNoAvailableNode will be returned if no node is available.
	ErrNoAvailableNode = errors.New("selector: no available node")
)

Types

type Selector

type Selector interface {
	AddNode(node *databasev1.Node)
	RemoveNode(node *databasev1.Node)
	Pick(group, name string, shardID uint32) (string, error)
	run.PreRunner
	fmt.Stringer
}

Selector keeps all data nodes in the memory and can provide different algorithm to pick an available node.

func NewMaglevSelector

func NewMaglevSelector() Selector

NewMaglevSelector creates a new backend selector based on Maglev hashing algorithm.

func NewPickFirstSelector

func NewPickFirstSelector() (Selector, error)

NewPickFirstSelector returns a simple selector that always returns the first node if exists.

func NewRoundRobinSelector

func NewRoundRobinSelector(schemaRegistry metadata.Repo) Selector

NewRoundRobinSelector creates a new round-robin selector.