在新的AppDomain中启动WCF服务以启用卷影副本(托管Windows服务)

时间:2014-06-25 13:54:41

标签: c# wcf windows-services appdomain shadow-copy

我有一个WCF服务库(MyWCFService),它使用MEF加载插件并由Windows服务托管(All .NET 4.0)。我现在尝试在新的AppDomain中运行它并启用ShadowCopyFiles,希望我可以在运行时更新插件。这是Windows服务项目中的代码。

Program.cs的

 static class Program
    {  
        static void Main()
        {  
            ServiceBase[] ServicesToRun;
            ServicesToRun = new ServiceBase[] 
            { 
               new MyService() 
            };
            ServiceBase.Run(ServicesToRun);
        }
    }

MyService.cs

  public partial class MyService: ServiceBase
    {
        internal static ServiceHost MyServiceHost = null;
        public MyService()
        {
             // this works but is deprecated..
             AppDomain.CurrentDomain.SetShadowCopyFiles();

            //this is not working.. DLLs still get locked. Require for a new AppDomain
            //AppDomain.CurrentDomain.SetupInformation.ShadowCopyFiles = "true";  

            InitializeComponent();
        }   

        protected override void OnStart(string[] args)
        {
            if(MyServiceHost  !=null)
            {
                MyServiceHost.Close();
            }
            try
            {
                MyServiceHost= new ServiceHost(typeof(MyWCFService));         
                MyServiceHost.Open();
            }
            catch(Exception)
            {
            }          
        }

        protected override void OnStop()
        {
            if (MyServiceHost!= null)
            {
                MyServiceHost.Close();
                MyServiceHost= null;
            }
        }       
    }

有没有办法呢?我做了很多搜索,但仍然不知道如何使用我当前的设置(或者我无法理解......)

我尝试在AppDomain内创建一个新的Main()并使用 domain.DoCallBack(new CrossAppDomainDelegate(() => { ServiceBase.Run(ServicesToRun); }))启动服务,但我无法启动服务并继续"Error 1053: The service did not respond to the start or control request in a timely fashion"

然后我尝试在AppDomain.CurrentDomain.SetupInformation.ShadowCopyFiles = "true"; MyWCFService.cs InitializeComponent();之前AppDomain.CurrentDomain.SetShadowCopyFiles();启用服务但是dll仍处于锁定状态,从而为当前appdomain启用了Shadow copy。但是,如果我使用{{1}}(一种已弃用的方法)来启用卷影副本,一切正常。我更困惑了。

1 个答案:

答案 0 :(得分:1)

好的,我最终创建了一个继承自MarshalByRefObject的shell / proxy类,并从那里启动服务,这里是代码:

ServiceShell.cs

public class ServiceShell:MarshalByRefObject
{
     internal static ServiceHost MyServiceHost = null;

     public void Run()
     {
         if (MyServiceHost != null)
         {
             MyServiceHost.Close();
         }
         try
         {
             MyServiceHost = new ServiceHost(typeof(MyWCFService));
             MyServiceHost.Open();
         }
         catch (Exception)
         {
         }          
     }

     public void Stop()
     {
         if (MyServiceHost!= null)
         {
             MyServiceHost.Close();
             MyServiceHost = null;
         }
     }
}

MyService.cs

public partial class MyService: ServiceBase
{        
    AppDomain domain;
    ServiceShell runner;

    public MyService()
    {   
        var setup = new AppDomainSetup
        {
            ShadowCopyFiles = "true"
        };
        domain = AppDomain.CreateDomain("MyServiceHostDomain", AppDomain.CurrentDomain.Evidence, setup);

        runner = (ServiceShell)domain.CreateInstanceAndUnwrap
            (typeof(ServiceShell).Assembly.FullName, typeof(ServiceShell).FullName);
        InitializeComponent();

    }

    protected override void OnStart(string[] args)
    {          
        runner.Run();
    }

    protected override void OnStop()
    {
        runner.Stop();
        AppDomain.Unload(domain);
    }       
}