import akka.actor.{Actor, ActorSystem, Props}

import com.typesafe.config.{Config, ConfigFactory}

import scala.collection.mutable

import scala.concurrent.duration._

class Master(val masterHost: String, val masterPort: Int) extends Actor{

// 用來存儲Worker的注冊信息

val idToWorker = new mutable.HashMap[String, WorkerInfo]()

// 用來存儲Worker的信息

val workers = new mutable.HashSet[WorkerInfo]()

// Worker的超時(shí)時(shí)間間隔

val checkInterval: Long = 15000

// 生命周期方法，在構(gòu)造器之后，receive方法之前只調(diào)用一次

override def preStart(): Unit = {

// 啟動一個(gè)定時(shí)器，用來定時(shí)檢查超時(shí)的Worker

import context.dispatcher

context.system.scheduler.schedule(0 millis, checkInterval millis, self, CheckTimeOutWorker)

}

// 在preStart方法之后，不斷的重復(fù)調(diào)用

override def receive: Receive = {

// Worker -> Master

case RegisterWorker(id, host, port, memory, cores) => {

if (!idToWorker.contains(id)){

val workerInfo = new WorkerInfo(id, host, port, memory, cores)

idToWorker += (id -> workerInfo)

workers += workerInfo

println("a worker registered")

sender ! RegisteredWorker(s"akka.tcp://${Master.MASTER_SYSTEM}" +

s"@${masterHost}:${masterPort}/user/${Master.MASTER_ACTOR}")

}

}

case HeartBeat(workerId) => {

// 通過傳過來的workerId獲取對應(yīng)的WorkerInfo

val workerInfo: WorkerInfo = idToWorker(workerId)

// 獲取當(dāng)前時(shí)間

val currentTime = System.currentTimeMillis()

// 更新最后一次心跳時(shí)間

workerInfo.lastHeartbeatTime = currentTime

}

case CheckTimeOutWorker => {

val currentTime = System.currentTimeMillis()

val toRemove: mutable.HashSet[WorkerInfo] =

workers.filter(w => currentTime - w.lastHeartbeatTime > checkInterval)

// 將超時(shí)的Worker從idToWorker和workers中移除

toRemove.foreach(deadWorker => {

idToWorker -= deadWorker.id

workers -= deadWorker

})

println(s"num of workers: ${workers.size}")

}

}

}

object Master{

val MASTER_SYSTEM = "MasterSystem"

val MASTER_ACTOR = "Master"

def main(args: Array[String]): Unit = {

val host = args(0)

val port = args(1).toInt

val configStr =

s"""

|akka.actor.provider = "akka.remote.RemoteActorRefProvider"

|akka.remote.netty.tcp.hostname = "$host"

|akka.remote.netty.tcp.port = "$port"

""".stripMargin

// 配置創(chuàng)建Actor需要的配置信息

val config: Config = ConfigFactory.parseString(configStr)

// 創(chuàng)建ActorSystem

val actorSystem: ActorSystem = ActorSystem(MASTER_SYSTEM, config)

// 用actorSystem實(shí)例創(chuàng)建Actor

actorSystem.actorOf(Props(new Master(host, port)), MASTER_ACTOR)

actorSystem.awaitTermination()

}

}

2.創(chuàng)建RemoteMsg特質(zhì)