iot/projects/IoT/IoT.Shared/Infrastructure/BaseClientService.cs

using Infrastructure.Extensions;
using Microsoft.AspNetCore.SignalR.Client;
using Microsoft.Extensions.Configuration;
using System;
using System.Threading;
using System.Threading.Tasks;

namespace IoT.Shared.Infrastructure
{
    public class BaseClientService : IClientService
    {
        protected string _notifyHost;
        protected HubConnection Connection;
        protected readonly IServiceProvider applicationServices;
        protected readonly IConfiguration _cfg;
        protected CancellationTokenSource _tokenSource;
        public string ConnectionId { get; private set; }

        public BaseClientService(IServiceProvider applicationServices, IConfiguration configuration)
        {
            this.applicationServices = applicationServices;
            this._cfg = configuration;
            this._tokenSource = new CancellationTokenSource();
            this.ConnectionId = Guid.NewGuid().ToBase62();
        }

        public void Start()
        {
            Task.Run(async () =>
            {
                while (!_tokenSource.IsCancellationRequested)
                {
                    this.Connect();
                    await Task.Delay(this._cfg.GetValue<int>("timer.seconds", 60) * 1000);
                }
            });
        }

        public void Connect()
        {
            if (this._cfg.GetValue<bool>("notify:enabled", false))
            {
                try
                {
                    if (Connection == null)
                    {
                        Console.WriteLine("connection is null");
                        InitConnection();
                    }
                    if (Connection.State == HubConnectionState.Disconnected)
                    {
                        Console.WriteLine("start connect");
                        if (this._notifyHost != this._cfg["notify:host"])
                        {
                            InitConnection();
                        }
                        Connection.StartAsync().Wait();
                        this.OnConnected();
                    }
                    else
                    {
                        if (this._notifyHost != this._cfg["notify:host"])
                        {
                            this.ReConnect(null);
                        }
                        else
                        {
                            Console.WriteLine($"connection has connected");
                        }
                    }
                }
                catch (Exception ex)
                {
                    ex.PrintStack();
                }
            }
            else
            {
                this.Close();
            }
        }

        public virtual void OnConnected()
        {
        }

        public virtual void ConnectionOn()
        {
        }

        public void Close()
        {
            if (this.Connection != null)
            {
                if (this.Connection.State == HubConnectionState.Connected)
                {
                    this.Connection.StopAsync();
                }
                this.Connection.DisposeAsync();
                this.Connection = null;
            }
        }

        private Task ReConnect(Exception arg)
        {
            this.Close();
            this.Connect();
            return Task.CompletedTask;
        }

        private void InitConnection()
        {
            this._notifyHost = this._cfg["notify:host"];
            var url = $"http://{this._notifyHost}/hub?group={this._cfg["connectId"]}";
            if (this.Connection != null)
            {
                this.Connection.DisposeAsync();
            }
            this.Connection = new HubConnectionBuilder().WithUrl(url).Build();
            this.Connection.Closed += ReConnect;
            this.Connection.On("ServerToClient", (string method, string message, string fromConnectionId) => this.OnServerToClient(method, message, fromConnectionId));
            this.ConnectionOn();
        }

        public virtual void OnServerToClient(string method, string message, string fromConnectionId)
        {
        }

        public void ClientToServer(string method, string message, string fromConnectionId = null)
        {
            Task.Run(() =>
            {
                try
                {
                    this.Connection.SendAsync("OnClientToServer", method, message, fromConnectionId);
                }
                catch (Exception ex)
                {
                    ex.PrintStack();
                }
            });
        }

        public void Dispose()
        {
            this._tokenSource.Cancel();
            this.Close();
        }
    }
}