《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()。

 1 using Proto;
 2 using System;
 3 using System.Threading;
 4 using System.Threading.Tasks;
 5 
 6 namespace P004_PID
 7 {
 8     class Program
 9     {
10         static void Main(string[] args)
11         {
12             var props = Actor.FromProducer(() => new MyActor()); 
13             var pid = Actor.Spawn(props);           
14             while (true)
15             {
16                 Console.WriteLine("**************************************");
17                 Console.WriteLine("1、单向请求Tell  2、单向请求Request  3、双向请求RequestAsync");
18                 switch (Console.ReadLine())
19                 {
20                     case "1":
21                         Console.WriteLine("单向请求开始");
22                         pid.Tell(new Request { Name = "单向请求 Tell", RequestType = "one-way", Time = DateTime.Now });
23                         break;
24                     case "2":
25                         Console.WriteLine("单向请求开始");
26                         //无法接回应签，与官网说法不一
27                         pid.Request(new Request { Name = "单向请求 Request", RequestType = "two-way-1", Time = DateTime.Now }, pid);
28                         
29                         break;
30                     case "3":
31                         Console.WriteLine("双向请求开始");
32                         var response = pid.RequestAsync<Response>(new Request { Name = "双向请求 RequestAsync", RequestType = "two-way-2", Time = DateTime.Now }).Result;
33                         Console.WriteLine(response.Time + ":" + response.Name);
34                         break;
35                 }
36                 Thread.Sleep(2000);
37             }
38         }
39     }
40 
41     public class MyActor : IActor
42     {
43         public Task ReceiveAsync(IContext context)
44         {
45 
46             if (context.Message is Request request)
47             {
48                 switch (request.RequestType)
49                 {
50                     case "one-way"://context.Sender为null
51                         Console.WriteLine("接收到：" + request.RequestType + "," + request.Time + ":" + request.Name);
52                         break;
53                     case "two-way-1"://context.Sender= context.Self为自己
54                         Console.WriteLine("接收到：" + request.RequestType + "," + request.Time + ":" + request.Name);                      
55                         context.Respond(new Response() { Time = DateTime.Now, Name = "服务端应答 two-way-1" });                    
56                         break;
57                     case "two-way-2"://context.Sender!= context.Self为新实例
58                         Console.WriteLine("接收到：" + request.RequestType + "," + request.Time + ":" + request.Name);                       
59                         context.Respond(new Response() { Time = DateTime.Now, Name = "服务端应答 two-way-2" });
60                         break;
61                 }
62             }
63             return Actor.Done;
64         }
65     }
66 
67     public class Request
68     {
69         public string Name
70         { get; set; }
71         public string RequestType
72         { get; set; }
73         public DateTime Time
74         { get; set; }
75     }
76 
77     public class Response
78     {
79         public string Name
80         { get; set; }
81         public DateTime Time
82         { get; set; }
83     }
84 }

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：