From e6808ed9edaaeb2398069d3da737e5e03bc942ed Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=E9=99=88=E5=9B=BD=E4=BC=9F?= <366193849@qq.com>
Date: Thu, 22 Jul 2021 13:12:17 +0800
Subject: [PATCH] =?UTF-8?q?dnscryptProxy=E6=9C=8D=E5=8A=A1=E5=81=A5?=
 =?UTF-8?q?=E5=BA=B7=E6=A3=80=E6=9F=A5?=
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---
 .../DnscryptProxyHostedService.cs             | 28 +++++++++++++++----
 1 file changed, 23 insertions(+), 5 deletions(-)

diff --git a/FastGithub.Dns.DnscryptProxy/DnscryptProxyHostedService.cs b/FastGithub.Dns.DnscryptProxy/DnscryptProxyHostedService.cs
index 3a8974c..9890585 100644
--- a/FastGithub.Dns.DnscryptProxy/DnscryptProxyHostedService.cs
+++ b/FastGithub.Dns.DnscryptProxy/DnscryptProxyHostedService.cs
@@ -10,7 +10,7 @@ namespace FastGithub.Dns.DnscryptProxy
     /// <summary>
     /// DnscryptProxy后台服务
     /// </summary>
-    sealed class DnscryptProxyHostedService : IHostedService
+    sealed class DnscryptProxyHostedService : BackgroundService
     {
         private const string dnscryptProxyFile = "dnscrypt-proxy";
         private readonly ILogger<DnscryptProxyHostedService> logger;
@@ -29,7 +29,7 @@ namespace FastGithub.Dns.DnscryptProxy
         /// </summary>
         /// <param name="cancellationToken"></param>
         /// <returns></returns>
-        public Task StartAsync(CancellationToken cancellationToken)
+        public override Task StartAsync(CancellationToken cancellationToken)
         {
             try
             {
@@ -48,7 +48,8 @@ namespace FastGithub.Dns.DnscryptProxy
             {
                 this.logger.LogWarning($"{dnscryptProxyFile}启动失败：{ex.Message}");
             }
-            return Task.CompletedTask;
+
+            return base.StartAsync(cancellationToken);
         }
 
         /// <summary>
@@ -56,7 +57,7 @@ namespace FastGithub.Dns.DnscryptProxy
         /// </summary>
         /// <param name="cancellationToken"></param>
         /// <returns></returns>
-        public Task StopAsync(CancellationToken cancellationToken)
+        public override Task StopAsync(CancellationToken cancellationToken)
         {
             try
             {
@@ -76,9 +77,26 @@ namespace FastGithub.Dns.DnscryptProxy
             {
                 this.logger.LogWarning($"{dnscryptProxyFile}停止失败：{ex.Message}");
             }
-            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)
+        {
+            while (stoppingToken.IsCancellationRequested == false)
+            {
+                await Task.Delay(TimeSpan.FromSeconds(10d), stoppingToken);
+                var processes = Process.GetProcessesByName(dnscryptProxyFile);
+                if (processes.Length == 0)
+                {
+                    this.logger.LogError($"检测到{dnscryptProxyFile}已停止运行，{nameof(FastGithub)}将无法使用。你可以把配置文件的PureDns修改为其它可用的DNS以临时使用。");
+                }
+            }
+        }
 
         /// <summary>
         /// 启动DnscryptProxy进程