C# 实现守护进程
这段时间在做一个关于数据交互的项目。接收到客户发送过来的文件后，通过Windows服务将文件按一定的规则分发到不同的MQ消息队列，然后再由不同的处理程序处理。虽然在编码中尽可能的考虑到了异常以及记录了详细的日志，但是服务还是偶尔抽风停掉了，这样就造成了文件堆积，客户请求得不到及时的响应。所以需要一个守护进程来保证服务始终是启动状态的。
首先，要保证需要监控的进程可配置，以及指定日志的保存位置。在App.config中配置日志保存路径以及需监控进程和对应的exe可执行程序的位置（之前考虑是如果没有该服务，则使用exe安装服务）。
<appSettings> <add key="LogPath" value="D:\Study"/> <add key="YTGDataExchangeProcess" value="d:\Study\YTGDataExchangeProcess.exe"/> </appSettings>
public class ServiceSearch { static List<ServiceProcessInfo> _ServiceList = new List<ServiceProcessInfo>(); static object _logLocker = new Object(); //日志记录位置 static readonly string _logPath; static ServiceSearch() { try { string[] appSettingsKeys = ConfigurationManager.AppSettings.AllKeys; foreach (string item in appSettingsKeys) { string value = ConfigurationManager.AppSettings[item].Trim(); //日志配置 if (item == "LogPath") { if (!string.IsNullOrEmpty(value)) { _logPath = string.Format("{0}\\ProcessMonitorLog", value); if (!Directory.Exists(_logPath)) { Directory.CreateDirectory(_logPath); } } } else { if (!string.IsNullOrEmpty(value)) { //应用程序是否存在 if (File.Exists(value)) { _ServiceList.Add(new ServiceProcessInfo { ServiceExePath = value, ServiceName = item }); } } } } } catch (Exception ex) { WriteLog(ex.Message); } } public static void StartMonitor() { if (_ServiceList.Count != 0) { foreach (ServiceProcessInfo info in _ServiceList) { string sevName = info.ServiceName; string sevExePath = info.ServiceExePath; if (!string.IsNullOrEmpty(sevExePath)) { //校验exe文件是否存在 if (File.Exists(sevExePath)) { ScanServiceManager(sevName, sevExePath); } } } } else { WriteLog("没有配置需要监控的服务！"); } } /// <summary> /// 查找服务的进程 /// 有则判断进程是否运行，非运行状态则启动 /// </summary> public static void ScanServiceManager(string serviceName, string serviceExePath) { try { ServiceController sevCtrler = new ServiceController(serviceName); //该服务已存在 //如果服务状态不为启动 if (sevCtrler.Status != ServiceControllerStatus.Running) { sevCtrler.Start(); } //创建监控线程 WatchService(serviceName); } catch (Exception ex) { //该服务不存在 WriteLog(string.Format(ex.Message)); } } /// <summary> /// 为配置的进程添加监控进程 /// </summary> /// <param name="pro"></param> /// <param name="processAddress"></param> public static void WatchService(string ServiceName) { ServiceMonitor monitor = new ServiceMonitor(ServiceName); Thread thread = new Thread(new ThreadStart(monitor.Monitor)); thread.IsBackground = true; thread.Start(); } /// <summary> /// 写日志 /// </summary> /// <param name="errMessage"></param> public static void WriteLog(string errMessage) { string logPath = _logPath; //没有配置日志目录，不记录 if (!string.IsNullOrEmpty(logPath)) { lock (_logLocker) { string fullName = string.Format("{0}\\{1}.log", logPath, DateTime.Now.ToString("yyyy-MM-dd")); if (!File.Exists(fullName)) { File.Create(fullName).Close(); } using (StreamWriter sw = new StreamWriter(fullName, true, Encoding.UTF8)) { sw.WriteLine(String.Format("[{0}]{1}", DateTime.Now.ToString("hh:mm:ss fff"), errMessage)); sw.Close(); } } } } public class ServiceProcessInfo { /// <summary> /// 服务名称 /// </summary> public string ServiceName { get; set; } /// <summary> /// 应用程序位置 /// </summary> public string ServiceExePath { get; set; } } }
上面ScanServiceManager方法中，使用serviceName实例化ServiceController对象，并启用一个单独的线程对其轮询，监控其状态；否则只会对第一个服务进行监控后阻塞。
public class ServiceMonitor { /// <summary> /// 服务名称 /// </summary> private string _ServiceName; public string ServiceName { get { return _ServiceName; } set { _ServiceName = value; } } public ServiceMonitor(string ServiceName) { this._ServiceName = ServiceName; } /// <summary> /// 监听服务 /// </summary> public void Monitor() { while (true) { try { ServiceController ctrler = new ServiceController(_ServiceName); if (ctrler.Status != ServiceControllerStatus.Running) { ServiceSearch.WriteLog(string.Format("正在启动服务{0}...", _ServiceName)); ctrler.Start(); ServiceSearch.WriteLog(string.Format("服务{0}启动成功！", _ServiceName)); } } catch (Exception ex) { ServiceSearch.WriteLog(string.Format("服务{0}启动失败，错误原因：{1}", _ServiceName, ex.Message)); } Thread.Sleep(1000 * 40); } } }
