[网络协议]akka remote配置监听端口配置无效

问题描述

从akka实战数据上看到demo代码搭建，如下：
服务器端：

class AkkademyDb extends Actor{

  val map = new mutable.HashMap[String, Any]()

  override def receive: Receive = {
    case SetRequest(key, value) =>
      println("set: key="+key+",value="+value)
      map.put(key, value)
      sender() ! Status.Success
    case GetRequest(key) =>
      println("get: key="+key)
      val option = map.get(key)
      option match {
        case Some(x) => sender() ! x
        case None => sender() ! Status.Failure(new KeyNotFoundException(key))
      }
    case o => Status.Failure(new ClassNotFoundException())
  }
}



object Main extends App{

  ConfigFactory.load("server")

  implicit val system = ActorSystem("akkademy",ConfigFactory.load("server"))
  system.actorOf(Props(classOf[AkkademyDb]),"akkademy-db")
}

服务器端配置：

akka{
    actor{
        provider="akka.remote.RemoteActorRefProvider"
    }
    remote{
        enabled-transports = ["akka.remote.netty.tcp"]
        netty.tcp{
            hostname = "127.0.0.1"
            port = 8089
        }
    }

}

启动后显示监听端口与配置文件中设置的端口不一致

INFO akka.remote.artery.tcp.ArteryTcpTransport - Remoting started with transport [Artery tcp]; listening on address [akka://akkademy@192.168.30.119:25520] with UID [4751388696144811708]

分析问题如下

怀疑配置项不对，导致程序使用了默认监听端口
需要分析源码，找到实现类读的配置项信息
将配置信息设置为正确的配置项
问题解决


从网上查找资料，找akka remote源码分析，发现一段话：
在ActorSystem初始化时，调用了RemoteActorRefProvider的init函数，init创建了Remoting这个RemoteTransport，并调用了start，而RemoteTransport作用是什么呢？

参

RemoteTransport源码

//是抽象类
private[akka] abstract class RemoteTransport(val system: ExtendedActorSystem, val provider: RemoteActorRefProvider) {

  /**
   * Shuts down the remoting
   */
  def shutdown(): Future[Done]

//找到两个实现类
private[remote] abstract class ArteryTransport
private[remote] class Remoting

//分别在两个实现类start方法上打断点，实际运行是ArteryTransport实现

查看官网文档，找到ArteryTransport使用配置文件格式

akka {
  actor {
    provider = remote
  }
  remote {
    artery {
      enabled = on
      canonical.hostname = "127.0.0.1"
      canonical.port = 25520
    }
  }
}

修改配置文件内容之后

akka {
  actor {
    provider = "akka.remote.RemoteActorRefProvider"
  }
  remote {
    netty.tcp {
      hostname = "127.0.0.1"
      port = 2554
    }
    artery {
          enabled = on
          canonical.hostname = "127.0.0.1"
          canonical.port = 25521
        }
  }

}
akka.actor.allow-java-serialization=on

启动服务端，监听端口改变

INFO akka.remote.artery.tcp.ArteryTcpTransport - Remoting started with transport [Artery tcp]; listening on address [akka://akkademy@127.0.0.1:25521] with UID [-4923684430470272955]

启动客户端报协议不对，是因为书里指定的协议不对，修改如下：

  val remotedDb = system.actorSelection(s"akka。tcp://akkademy@$remoteAddress/user/akkademy-db")
  修改为：
    val remotedDb = system.actorSelection(s"akka://akkademy@$remoteAddress/user/akkademy-db")

程序还报序列化有问题

需要将作为消息的样例类实现Serializable
case class SetRequest(key: String, value: Any) extends Serializable

在配置中打开java 序列化开关
akka.actor.allow-java-serialization=on

到此demo调试成功

参考链接: https://www.cnblogs.com/gabry/p/9389558.html