《通过C#学Proto.Actor模型》之PID

PID对象是代表Actor对象的进程，是能过Actor.Spawn(props)获取的；它有什么成员呢？既然代理Actor，首先有一个ID，标识自己是谁，Actor在Spawn时可以命名这个ID，否则会自动生成。还有三种向邮箱发消息的方法，Tell()，Request()，RequestAsync()，还有一个发送系统消息(Started,Stoping,Stoped等)方法SendSystemMessage()，还有一个停止的方法Stop()。

 using Proto;
 using System;
 using System.Threading;
 using System.Threading.Tasks;

 namespace P004_PID
 {
     class Program
     {
         static void Main(string[] args)
         {
             var props = Actor.FromProducer(() => new MyActor());
             var pid = Actor.Spawn(props);
             while (true)
             {
                 Console.WriteLine("**************************************");
                 Console.WriteLine("1、单向请求Tell  2、单向请求Request  3、双向请求RequestAsync");
                 switch (Console.ReadLine())
                 {
                     case "":
                         Console.WriteLine("单向请求开始");
                         pid.Tell(new Request { Name = "单向请求 Tell", RequestType = "one-way", Time = DateTime.Now });
                         break;
                     case "":
                         Console.WriteLine("单向请求开始");
                         //无法接回应签，与官网说法不一
                         pid.Request(new Request { Name = "单向请求 Request", RequestType = "two-way-1", Time = DateTime.Now }, pid);

                         break;
                     case "":
                         Console.WriteLine("双向请求开始");
                         var response = pid.RequestAsync<Response>(new Request { Name = "双向请求 RequestAsync", RequestType = "two-way-2", Time = DateTime.Now }).Result;
                         Console.WriteLine(response.Time + ":" + response.Name);
                         break;
                 }
                 Thread.Sleep();
             }
         }
     }

     public class MyActor : IActor
     {
         public Task ReceiveAsync(IContext context)
         {

             if (context.Message is Request request)
             {
                 switch (request.RequestType)
                 {
                     case "one-way"://context.Sender为null
                         Console.WriteLine("接收到：" + request.RequestType + "," + request.Time + ":" + request.Name);
                         break;
                     case "two-way-1"://context.Sender= context.Self为自己
                         Console.WriteLine("接收到：" + request.RequestType + "," + request.Time + ":" + request.Name);
                         context.Respond(new Response() { Time = DateTime.Now, Name = "服务端应答 two-way-1" });
                         break;
                     case "two-way-2"://context.Sender!= context.Self为新实例
                         Console.WriteLine("接收到：" + request.RequestType + "," + request.Time + ":" + request.Name);
                         context.Respond(new Response() { Time = DateTime.Now, Name = "服务端应答 two-way-2" });
                         break;
                 }
             }
             return Actor.Done;
         }
     }

     public class Request
     {
         public string Name
         { get; set; }
         public string RequestType
         { get; set; }
         public DateTime Time
         { get; set; }
     }

     public class Response
     {
         public string Name
         { get; set; }
         public DateTime Time
         { get; set; }
     }
 }

Actor中的Receive接到消息后，Context是中有两个PID对象，一个Self，一个Sender，Tell方法到达后，Sender对象为空；Request到达后，Sender=Self；而RequestAsync则Sender,Self都有对象，但不相同，这是一个区别。再有就是Tell和Request都是单向调用（我实测与官方文档说明有出入），RequestAsync是可以有返回值的，详见代码，如下是运行结果：