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package lb
import (
"sync/atomic"
"github.com/go-kit/kit/endpoint"
"github.com/go-kit/kit/sd"
)
// NewRoundRobin returns a load balancer that returns services in sequence.
func NewRoundRobin(s sd.Endpointer) Balancer {
return &roundRobin{
s: s,
c: 0,
}
}
type roundRobin struct {
s sd.Endpointer
c uint64
}
func (rr *roundRobin) Endpoint() (endpoint.Endpoint, error) {
endpoints, err := rr.s.Endpoints()
if err != nil {
return nil, err
}
if len(endpoints) <= 0 {
return nil, ErrNoEndpoints
}
old := atomic.AddUint64(&rr.c, 1) - 1
idx := old % uint64(len(endpoints))
return endpoints[idx], nil
}
|
