thegeekyasian / round-robin-go Goto Github PK

I have array of workers. Now I want to put these worker in round-robin. How may I pass array in New so that when I do Next task should assign the next worker.

Please help.

Thanks in advance.

Description

Starting from the second round, the first object will be fetched twice

Code

// go version: 1.18
package main

import (
	"fmt"
	"net/url"

	roundrobin "github.com/thegeekyasian/round-robin-go"
)

func main() {
	rr, _ := roundrobin.New(
		&url.URL{Host: "192.168.0.1"},
		&url.URL{Host: "192.168.0.2"},
		&url.URL{Host: "192.168.0.3"},
		&url.URL{Host: "192.168.0.4"},
	)

	for i := 0; i < 20; i++ {
		fmt.Println(rr.Next().Host)
	}
}

// output
192.168.0.1
192.168.0.2
192.168.0.3
192.168.0.4
192.168.0.1
192.168.0.1
192.168.0.2
192.168.0.3
192.168.0.4
192.168.0.1
192.168.0.1

Why？

when the next field is greater than the length of the object, the first object will be fetched and next will be reset to 0. The next time the Next method is called, next field will be 1, so the first object will be fetched.

// Next returns the next object.
func (r *RoundRobin[O]) Next() *O {
	n := atomic.AddUint32(&r.next, 1)

	if int(n) > len(r.objects) {
		atomic.StoreUint32(&r.next, 0) // reset next field
		n = 1
	}
	return r.objects[(int(n)-1)%len(r.objects)]
}