Orleans[NET Core 3.1] 学习笔记（四）（ 2 ）获取Grain的方式

简介

在这一节，我们将介绍如何在Silo和Client中获取Grain及调用Grain

Grain获取方式

从Grain内部获取：

//根据特定的Key值创建或获取指定的GrainIStudent student = GrainFactory.GetGrain<IStudent>(studentID);

从Client获取：

IStudent player = client.GetGrain<IStudent>(studentID);

应用

我们在项目中新增一个教室的概念，学生入学需要到教室先报个到才能分配到学号

1.修改 IStudent ，新增两个接口

        [...]        /// <summary>        /// 设置个人信息        /// </summary>        /// <param name="studentId">学号</param>        /// <param name="studentName">姓名</param>        /// <returns></returns>        Task SetStudentInfo(int studentId, string studentName);        /// <summary>        /// 接收消息        /// </summary>        /// <param name="code">消息code类型</param>        /// <param name="senderId">消息发送人id</param>        /// <param name="message">消息内容</param>        /// <returns></returns>        Task ReceiveMessages(string code, object senderId, string message);        [...]

2.修改 Student

        /// <summary> 学号 </summary>        private int Id;        /// <summary> 姓名 </summary>        private string Name;        [...]        public Task SetStudentInfo(int studentId, string studentName)        {            Id = studentId;            Name = studentName;            return Task.CompletedTask;        }        public Task ReceiveMessages(string code, object senderId, string message)        {            switch (code)            {                case "加入新同学":                    {                        ConsoleHelper.WriteSuccessLine($"【{Name}】：欢迎新同学");                        break;                    }                case "同学发言":                    {                        ConsoleHelper.WriteSuccessLine($"【{Name}】听到了学号为【{senderId}】的同学说的【{message}】");                        break;                    }                default:                    {                        ConsoleHelper.WriteSuccessLine($"【{Name}】：我听不懂你们在说啥");                        break;                    }            }            return Task.CompletedTask;        }        [...]

3.在 IGrains 中新增 IClassroom

namespace IGrains{    /// <summary>    /// 教室    /// </summary>    public interface IClassroom : Orleans.IGrainWithIntegerKey    {        /// <summary>        /// 报名登记并拿到学号        /// </summary>        /// <param name="name">姓名</param>        /// <returns></returns>        Task<int> Enroll(string name);        /// <summary>        /// 学生入座        /// </summary>        /// <param name="student"></param>        /// <returns></returns>        Task<bool> Seated(IStudent student);        /// <summary>        /// 发言        /// </summary>        /// <param name="student">当前的学生</param>        /// <param name="message">发言内容</param>        /// <returns></returns>        Task<bool> Speech(IStudent student, string message);    }}

4.在 Grains 中新增 Classroom

using IGrains;using Orleans;using System.Collections.Generic;using System.Linq;using System.Threading.Tasks;namespace Grains{    /// <summary>    /// 教室    /// </summary>    public class Classroom : Orleans.Grain, IClassroom    {        /// <summary> 教室内的学生 </summary>        private List<IStudent> Students = new List<IStudent>();        /// <summary>        /// 报名登记并拿到学号        /// </summary>        /// <param name="name">姓名</param>        /// <returns></returns>        public async Task<int> Enroll(string name)        {            int studentID = Students.Count() + 1;            var aaa = this.GetPrimaryKeyLong();            IStudent student = GrainFactory.GetGrain<IStudent>(studentID);            await student.SetStudentInfo(studentID, name);//等待一下            Students.Add(student);            return studentID;        }        /// <summary>        /// 学生入座        /// </summary>        /// <param name="student"></param>        /// <returns></returns>        public Task<bool> Seated(IStudent student)        {            if (!Students.Contains(student))            {                return Task.FromResult(false);//没登记的学生不给坐            }            foreach (var item in Students)            {                if (item.GetPrimaryKeyLong() != student.GetPrimaryKeyLong())                {                    item.ReceiveMessages("加入新同学", this.GetPrimaryKeyLong(), $"学号{student.GetPrimaryKeyLong()}的童靴加入了我们，大家欢迎");//不等待                }            }            return Task.FromResult(true);        }        /// <summary>        /// 发言        /// </summary>        /// <param name="student">当前的学生</param>        /// <param name="message">发言内容</param>        public Task<bool> Speech(IStudent student, string message)        {            if (!Students.Contains(student))            {                return Task.FromResult(false);//没登记的学生闭嘴            }            foreach (var item in Students)            {                if (item.GetPrimaryKeyLong() != student.GetPrimaryKeyLong())                {                    item.ReceiveMessages("同学发言", (int)student.GetPrimaryKeyLong(), message);//不等待                }            }            return Task.FromResult(true);        }    }}

5.新增新的Orleans客户端项目，创建 asp.net core mvc 项目 Client_WebMVCApp

使用NuGet引用 Microsoft.Orleans.Client（3.0.2）

新增 OrleansService

namespace Client_WebMVCApp.Services{    public class OrleansService : IOrleansService    {        private readonly IClusterClient clusterClient;        public OrleansService()        {            clusterClient = ConnectClient().Result;        }        public T GetGrain<T>(long integerKey) where T : IGrainWithIntegerKey        {            return clusterClient.GetGrain<T>(integerKey);        }        /// <summary>        /// 使用本地配置连接服务        /// </summary>        /// <returns></returns>        private async Task<IClusterClient> ConnectClient()        {            IClusterClient client;            client = new ClientBuilder()                .UseLocalhostClustering()           //配置客户端以连接到本地主机上的筒仓。                .Configure<ClusterOptions>(options =>                {                    options.ClusterId = "dev";                    options.ServiceId = "MyHost";                })                .Build();            await client.Connect();            return client;        }    }}

然后修改 Startup ，把Orleans配置上去

        [...]        public void ConfigureServices(IServiceCollection services)        {            services.AddControllersWithViews();             services.AddTransient<OrleansService>();//注册一下Orleans        }        [...]

再修改 HomeController ，咱们来把上面注入的 OrleansService 使用起来

        [...]        private readonly OrleansService _orleansService;        private readonly IClassroom _classroom;        public HomeController(ILogger<HomeController> logger, OrleansService orleansService)        {            _logger = logger;            _orleansService = orleansService;            _classroom = _orleansService.GetGrain<IClassroom>(0);        }        /// <summary>        /// 报名拿学号        /// </summary>        /// <param name="name">学生姓名</param>        /// <returns></returns>        [HttpGet]        public async Task<IActionResult> GetStudentId(string name)        {            var studentId = await _classroom.Enroll(name);            IStudent student = _orleansService.GetGrain<IStudent>(studentId);            _classroom.Seated(student);//落座，不等待它            //return Json(new { Success = true, Data = studentId, Message = "获取成功！" });            return new JsonResult(new { Success = true, Data = studentId, Message = "获取成功！" });        }        [...]

6.运行起来

我们先把 Silo_ConsoleApp 跑起来

然后把 Client_WebMVCApp 跑起来，注意，这里我的端口用的是 4003,按照顺序请求如下接口：

http://localhost:4003/home/getstudentid?name=张三http://localhost:4003/home/getstudentid?name=李四http://localhost:4003/home/getstudentid?name=王二麻

我们能看到 Silo_ConsoleApp.exe 打印如下日志：

好了，大功告成。

张三、李四、王二麻三个人排着队报名入座，李四坐下的时候张三欢迎他，王二麻坐下的时候张三李四一起欢迎他，ojbk，完美