broadcast.go

package examples

import (
	. "github.com/danalex97/Speer/interfaces"

	"fmt"
)

type BroadcastExample struct {
	Transport

	id     string
	parent string

	members []string
	time    func() int
}

func (s *BroadcastExample) New(util NodeUtil) Node {
	return &BroadcastExample{
		Transport: util.Transport(),

		id:     util.Id(),
		parent: util.Join(),

		members: []string{util.Id()},
		time:    util.Time(),
	}
}

func (s *BroadcastExample) root() bool {
	return s.parent == ""
}

type Join struct {
	id string
}

type NewMember struct {
	id string
}

type SomeBroadcast struct {
	ts   int
	list []string
	from string
}

func (s *BroadcastExample) broadcast(m interface{}) {
	for _, member := range s.members {
		s.ControlSend(member, m)
	}
}

func (s *BroadcastExample) OnJoin() {
	if !s.root() {
		s.ControlSend(s.parent, Join{
			id: s.id,
		})
	}
}

func (s *BroadcastExample) OnNotify() {
	select {
	case m, _ := <-s.ControlRecv():
		switch msg := m.(type) {
		case Join:
			if !s.root() {
				// subscribe in the list of nodes
				s.ControlSend(s.parent, msg)
			} else {
				// if the root receives a new node, broadcast the message
				s.members = append(s.members, msg.id)
				s.broadcast(NewMember{
					id: msg.id,
				})
			}
		case NewMember:
			if !s.root() {
				if msg.id != s.id {
					s.members = append(s.members, msg.id)
					s.broadcast(SomeBroadcast{
						ts:   s.time(),
						list: s.members,
						from: s.id,
					})
				}
			}
		case SomeBroadcast:
			fmt.Println(s.id, "recv:", msg)
		}
	default:
	}
}

func (s *BroadcastExample) OnLeave() {
}