《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 "1":
                        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 "2":
                        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 "3":
                        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(2000);
            }
        }
    }

    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：