增加代理检测功能

FastGithub/AppHostedService.cs

@@ -1,30 +1,119 @@
-using Microsoft.Extensions.Hosting;
+using FastGithub.Configuration;
+using Microsoft.Extensions.Hosting;
 using Microsoft.Extensions.Logging;
+using Microsoft.Extensions.Options;
+using System;
+using System.Linq;
+using System.Net;
+using System.Net.Http;
 using System.Threading;
 using System.Threading.Tasks;
 
 namespace FastGithub
 {
-    sealed class AppHostedService : IHostedService
+    /// <summary>
+    /// app后台服务
+    /// </summary>
+    sealed class AppHostedService : BackgroundService
     {
+        private readonly IOptions<FastGithubOptions> options;
         private readonly ILogger<AppHostedService> logger;
 
-        public AppHostedService(ILogger<AppHostedService> logger)
+        public AppHostedService(
+            IOptions<FastGithubOptions> options,
+            ILogger<AppHostedService> logger)
         {
+            this.options = options;
             this.logger = logger;
         }
 
-        public Task StartAsync(CancellationToken cancellationToken)
+        /// <summary>
+        /// 启动完成
+        /// </summary>
+        /// <param name="cancellationToken"></param>
+        /// <returns></returns>
+        public override Task StartAsync(CancellationToken cancellationToken)
         {
             var version = ProductionVersion.Current;
             this.logger.LogInformation($"{nameof(FastGithub)}启动完成，当前版本为v{version}，访问https://github.com/dotnetcore/FastGithub关注新版本");
-            return Task.CompletedTask;
+            return base.StartAsync(cancellationToken);
         }
 
-        public Task StopAsync(CancellationToken cancellationToken)
+        /// <summary>
+        /// 停止完成
+        /// </summary>
+        /// <param name="cancellationToken"></param>
+        /// <returns></returns>
+        public override Task StopAsync(CancellationToken cancellationToken)
         {
             this.logger.LogInformation($"{nameof(FastGithub)}已停止运行");
-            return Task.CompletedTask;
+            return base.StopAsync(cancellationToken);
+        }
+
+        /// <summary>
+        /// 后台任务
+        /// </summary>
+        /// <param name="stoppingToken"></param>
+        /// <returns></returns>
+        protected override async Task ExecuteAsync(CancellationToken stoppingToken)
+        {
+            if (OperatingSystem.IsWindows() == false)
+            {
+                await Task.Delay(TimeSpan.FromSeconds(1d), stoppingToken);
+                if (await this.UseFastGithubProxyAsync() == false)
+                {
+                    this.logger.LogWarning($"请手工设置系统代理为http://127.0.0.1:38457或自动代理为http://127.0.0.1:38457/proxy.pac");
+                }
+            }
+        }
+
+        /// <summary>
+        /// 应用fastgithub代理
+        /// </summary>
+        /// <param name="proxyServer"></param>
+        /// <param name="httpProxyPort"></param>
+        /// <returns></returns>
+        private async Task<bool> UseFastGithubProxyAsync()
+        {
+            var systemProxy = HttpClient.DefaultProxy;
+            if (systemProxy == null)
+            {
+                return false;
+            }
+
+            var domain = this.options.Value.DomainConfigs.Keys.FirstOrDefault();
+            if (domain == null)
+            {
+                return true;
+            }
+
+            var destination = new Uri($"https://{domain.Replace('*', 'a')}");
+            var proxyServer = systemProxy.GetProxy(destination);
+            if (proxyServer == null)
+            {
+                return false;
+            }
+
+            var httpProxyPort = this.options.Value.HttpProxyPort;
+            if (proxyServer.Port != httpProxyPort)
+            {
+                return false;
+            }
+
+            if (IPAddress.TryParse(proxyServer.Host, out var address))
+            {
+                return address.Equals(IPAddress.Loopback);
+            }
+
+            try
+            {
+                var addresses = await System.Net.Dns.GetHostAddressesAsync(proxyServer.Host);
+                return addresses.Contains(IPAddress.Loopback);
+            }
+            catch (Exception)
+            {
+                return false;
+            }
         }
     }
 }