// Package selector is for node selection and load balancing
package selector // import "go.unistack.org/micro/v3/selector"

import (
	"errors"
)

// ErrNoneAvailable is returned by select when no routes were provided to select from
var ErrNoneAvailable = errors.New("none available")

// Selector selects a route from a pool
type Selector interface {
	// Select a route from the pool using the strategy
	Select([]string, ...SelectOption) (Next, error)
	// Record the error returned from a route to inform future selection
	Record(string, error) error
	// Reset the selector
	Reset() error
	// String returns the name of the selector
	String() string
}

// Next returns the next node
type Next func() string