Question

我正在使用ASP.Net Web API 2 / .Net 4.5.2。

我在排队后台工作项时试图保留调用主体。为此，我试图：

Thread.CurrentPrincipal = callingPrincipal;

但是当我这样做时，我得到一个ObjectDisposedException：

System.ObjectDisposedException：安全句柄已关闭

如何将当前主体保留在后台工作项中？
我可以以某种方式复制校长吗？

public void Run<T>(Action<T> action)
{
    _logger.Debug("Queueing background work item");
    var callingPrincipal = Thread.CurrentPrincipal;
    HostingEnvironment.QueueBackgroundWorkItem(token =>
    {
        try
        {
            // UNCOMMENT - THROWS EXCEPTION
            // Thread.CurrentPrincipal = callingPrincipal;
            _logger.Debug("Executing queued background work item");
            using (var scope = DependencyResolver.BeginLifetimeScope())
            {
                var service = scope.Resolve<T>();
                action(service);
            }
        }
        catch (Exception ex)
        {
            _logger.Fatal(ex);
        }
        finally
        {
            _logger.Debug("Completed queued background work item");
        }
    });
}

Answer 1

结果manifestBlob += "\n"; manifestBlob += "// File: manifest.json\n"; manifestBlob += "//\n"; manifestBlob += "// Description:\n"; manifestBlob += "// manifest for chrome plug-in\n"; manifestBlob += "\n"; manifestBlob += "{\n"; manifestBlob += " \"manifest_version\": 2,\n"; manifestBlob += "\n"; manifestBlob += " \"version\": \"0.0.0\",\n"; manifestBlob += "\n"; manifestBlob += " // the ID is: sdfjkghsdfjkghjksdfghjkf hjkdfjff\n"; manifestBlob += " \"key\": \"sdfjkhsdfjkghjksdfghkjsdhgs djkgfhjklsdfhgjklsdfhgjklsdhfgkljsdfhgkljsdhklgjsdhfjklghsd fjklghsdjklfghjksdfhgjksdhfgjklhsdfjkl\",\n"; manifestBlob += "\n"; manifestBlob += " \"content_scripts\": [ { \"matches\": [\"http://*/*\", \"https://*/*\"], \"js\": [\"content.js\"] , \"run_at\": \"document_start\" } ],\n"; manifestBlob += "\n"; manifestBlob += " // this is the standard LOCAL install location - but if this extension is published to the app-st ore, this value gets overridden (that is okay and even good )\n"; manifestBlob += " \"update_url\": \"file:///C:/Program%2 0Files/MyProduct/Update.xml\",\n"; manifestBlob += "}\n";现在有一个复制构造函数。

ClaimsPrincipal

这似乎可以在保留所有身份和声明信息的同时解决问题。完整的功能如下：

var principal = new ClaimsPrincipal(Thread.CurrentPrincipal);

Answer 2

您的情况问题是在Thread.CurrentPrincipal处置后执行的后台任务。这是因为ASP.NET模型 - 在用户上下文中处理请求，之后释放了与用户对应的所有值。所以这恰好发生在你的身份上。尝试保存有关用户及其身份的信息，以便以后模拟它。

您可以查看support article from Microsoft以模拟ASP.NET网站中的操作，但我不认为这会对您有所帮助：

System.Security.Principal.WindowsImpersonationContext impersonationContext;
impersonationContext = 
    ((System.Security.Principal.WindowsIdentity)callingPrincipal.Identity).Impersonate();

//Insert your code that runs under the security context of the authenticating user here.

impersonationContext.Undo();

或者，可能是，您可以使用User.Token，如下所示：

HostingEnvironment.QueueBackgroundWorkItem(token =>
{
    try
    {
        _logger.Debug("Executing queued background work item");
        using (HostingEnvironment.Impersonate(callingPrincipal.Identity))
        {
            using (var scope = DependencyResolver.BeginLifetimeScope())
            {
                var service = scope.Resolve<T>();
                action(service);
            }
        }
        // UNCOMMENT - THROWS EXCEPTION
        // Thread.CurrentPrincipal = callingPrincipal;
    }
    catch (Exception ex)
    {
        _logger.Fatal(ex);
    }
    finally
    {
        _logger.Debug("Completed queued background work item");
    }
});

我建议您检查一下您的体系结构设计，以便找到一种方法将后台操作移出到其他上下文，其中用户身份将保持更长时间。其他方式，例如，使用将当前OperationContext传递给Task：

// store local operation context
var operationContext = OperationContext.Current;
TaskFactory.StartNew(() =>
{
    // initialize the current operation context
    OperationContext.Current = operationContext;
    action();
})

在校对后台工作项中保留主体

2 个答案: