loadbalance

Documentation

Index

• Constants
• Variables
• type BalancerFactory
  • func NewBalancerFactory(config Config) *BalancerFactory
  • func (b *BalancerFactory) GetInstance(ctx context.Context, req *protocol.Request) (discovery.Instance, error)
• type Config
• type Loadbalancer
  • func NewWeightedBalancer() Loadbalancer
• type Options
  • func (v *Options) Check()

Constants

const (
	DefaultRefreshInterval = 5 * time.Second
	DefaultExpireInterval  = 15 * time.Second
)

Variables

var DefaultLbOpts = Options{
	RefreshInterval: DefaultRefreshInterval,
	ExpireInterval:  DefaultExpireInterval,
}

Types

type BalancerFactory

type BalancerFactory struct {
	// contains filtered or unexported fields
}

func NewBalancerFactory

func NewBalancerFactory(config Config) *BalancerFactory

NewBalancerFactory get or create a balancer with given target. If it has the same key(resolver.Target(target)), we will cache and reuse the Balance.

func (*BalancerFactory) GetInstance

func (b *BalancerFactory) GetInstance(ctx context.Context, req *protocol.Request) (discovery.Instance, error)

type Config

type Config struct {
	Resolver discovery.Resolver
	Balancer Loadbalancer
	LbOpts   Options
}

type Loadbalancer

type Loadbalancer interface {
	// Pick is used to select an instance according to discovery result
	Pick(discovery.Result) discovery.Instance

	// Rebalance is used to refresh the cache of load balance's information
	Rebalance(discovery.Result)

	// Delete is used to delete the cache of load balance's information when it is expired
	Delete(string)

	// Name returns the name of the Loadbalancer.
	Name() string
}

Loadbalancer picks instance for the given service discovery result.

func NewWeightedBalancer

func NewWeightedBalancer() Loadbalancer

NewWeightedBalancer creates a loadbalancer using weighted-random algorithm.

type Options

type Options struct {
	// refresh discovery result timely
	RefreshInterval time.Duration

	// Balancer expire check interval
	// we need remove idle Balancers for resource saving
	ExpireInterval time.Duration
}

Options for LoadBalance option

func (*Options) Check

func (v *Options) Check()

Check checks option's param