如何将数据从 AuthorizationHandler 传递到 Asp.net 核心中的控制器

Question

我对用户登录使用了特定的授权策略，因此创建了自定义授权处理程序。如果他们未能通过政策，我想显示使用特定的警报消息。我阅读了文档，发现我可以通过转换 AuthorizationHandlerContext 来访问 AuthorizationFilterContext。我试图将消息添加到 HttpContext.Items 属性并在我的控制器中访问它，但是当我使用 TryGetValue 方法检查它时它返回 false。

if (context.HasFailed && context.Resource is AuthorizationFilterContext mvcContext)
{
 mvcContext.HttpContext.Items["message"] = "alert message";
}

这是我在控制器操作中使用的代码，将在授权失败时执行，

public IActionResult Login()
        {
            bool t = HttpContext.Items.TryGetValue("message", out Object e);
            //t is false
            TempData["message"] = e as string;
            return View();
        }

这是我注册所有身份验证服务的启动类。

services.AddAuthentication(CookieAuthenticationDefaults.AuthenticationScheme)
                    .AddCookie(options =>
                    {
                        options.AccessDeniedPath = "/Account/Login";
                        options.LoginPath = "/Account/Login";
                    });
            services.AddAuthorization(options =>
            {
                options.AddPolicy("CustomRequirement", policy => policy.Requirements.Add(new CustomRequirement()));
            });

有什么办法可以解决吗？

---

添加了完整的处理程序。

public class CustomRequirementHandler : AuthorizationHandler<CustomRequirement>
    {

        protected override Task HandleRequirementAsync(AuthorizationHandlerContext context, CustomRequirement requirement)
        {
            Dictionary<string, string> claims = context.User.Claims.ToDictionary(p => p.Type, p => p.Value);
            if (claims.TryGetValue("SessionId", out string sessionId) && claims.TryGetValue("UserId", out string userName) )
            {
                bool qq = ;//we check session id and user id that is stored in our database, true if valid.
                if (qq)
                {
                    context.Succeed(requirement);
                }
                else
                {
                    context.Fail();
                }
            }
            else
            {
                context.Fail();
            }

            if (context.HasFailed && context.Resource is AuthorizationFilterContext mvcContext)


   {
            var tempData = _tempDictionaryFactory.GetTempData(mvcContext.HttpContext);
            tempData["message"] = "alert message";
        }

        return Task.CompletedTask;
    }
}

我想添加这会使依赖注入？

private ITempDataDictionaryFactory _tempDictionaryFactory;

        public SingleConcurrentSessionHandler(ITempDataDictionaryFactory tempDataDictionaryFactory)
        {
            _tempDictionaryFactory = tempDataDictionaryFactory;
        }

---

更新- 这是带有自定义 AuthorizationHandler 的新空项目的记录器日志。

info: Microsoft.AspNetCore.Hosting.Internal.WebHost[1]
      Request starting HTTP/1.1 GET http://localhost:50236/
info: Microsoft.AspNetCore.Authorization.DefaultAuthorizationService[2]
      Authorization failed for user: (null).
info: Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker[3]
      Authorization failed for the request at filter 'Microsoft.AspNetCore.Mvc.Authorization.AuthorizeFilter'.
info: Microsoft.AspNetCore.Mvc.ChallengeResult[1]
      Executing ChallengeResult with authentication schemes ().
info: Microsoft.AspNetCore.Authentication.Cookies.CookieAuthenticationHandler[12]
      AuthenticationScheme: Cookies was challenged.
info: Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker[2]
      Executed action WebApplication1.HomeController.Index (WebApplication1) in 6217.0905ms
info: Microsoft.AspNetCore.Hosting.Internal.WebHost[2]
      Request finished in 6389.8033ms 302
info: Microsoft.AspNetCore.Hosting.Internal.WebHost[1]
      Request starting HTTP/1.1 GET http://localhost:50236/Account/Login?ReturnUrl=%2F
info: Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker[1]
      Executing action method WebApplication1.Controllers.AccountController.Login (WebApplication1) with arguments ((null)) - ModelState is Valid
info: Microsoft.AspNetCore.Mvc.Formatters.Json.Internal.JsonResultExecutor[1]
      Executing JsonResult, writing value .
info: Microsoft.AspNetCore.Mvc.Internal.ControllerActionInvoker[2]
      Executed action WebApplication1.Controllers.AccountController.Login (WebApplication1) in 3723.1458ms
info: Microsoft.AspNetCore.Hosting.Internal.WebHost[2]
      Request finished in 3741.0345ms 200 application/json; charset=utf-8
info: Microsoft.AspNetCore.Hosting.Internal.WebHost[1]
      Request starting HTTP/1.1 GET http://localhost:50236/favicon.ico
info: Microsoft.AspNetCore.Hosting.Internal.WebHost[2]
      Request finished in 4.1151ms 404 text/plain

Answer 1

使用 TempData 显示您的消息

有你需要的ITempDataDictionaryFactory和/IHttpContextAccessor或你可以从mvcContext.HttpContext

if (context.HasFailed && context.Resource is AuthorizationFilterContext mvcContext)
{
    var tempData = _tempDataDictionaryFactory.GetTempData(mvcContext.HttpContext);
    tempData["message"] = "alert message";
}

然后您可以通过 TempData 在 Login 方法中获取它

public IActionResult Login()
{
    string message = null;
    var item = TempData.FirstOrDefault(x =>x.Key == key);

    if (item.Value != null)
    {
        message = (string)item.Value;
    }

     return View();
}

为什么你的代码不起作用：

HttpContext创建每个请求这意味着您插入mvcContext.HttpContext.Items["message"] = "alert message";只能用于当前请求，当您在控制器或他的方法中使用授权时，它会将您的消息插入当前请求并重定向到您的 AccessDeniedPath 或 LoginPath 并且HttpContext将为此请求创建新的，而无需您信息。要在请求之间共享一些信息，您可以使用 TempData 或其他方法。

更新尝试从访问器获取 httpContext 完整代码

添加到启动 services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();

public class CustomRequirementHandler : AuthorizationHandler<CustomRequirement>
    {
        private readonly IHttpContextAccessor _httpContext;
        private readonly ITempDataDictionaryFactory _tempDataDictionaryFactory;

        public CustomRequirementHandler(IHttpContextAccessor httpContext, ITempDataDictionaryFactory tempDataDictionary)
        {
            _httpContext = httpContext;
            _tempDataDictionaryFactory = tempDataDictionary;
        }

        protected override Task HandleRequirementAsync(AuthorizationHandlerContext context, CustomRequirement requirement)
        {
            ///////
            //Your logic
            ///////

            if (context.HasFailed)
            {
                var tempData = _tempDataDictionaryFactory.GetTempData(_httpContext.HttpContext);
                tempData["message"] = "alert message";
            }

            return Task.CompletedTask;
        }
    }

UPDATE当 context.Fail(); 执行的 tempData 不通过 tempdata 提供程序注入，但您可以调用 tempdata 提供程序来执行手动保存

这里的例子：

public class CustomRequirementHandler : AuthorizationHandler<CustomRequirement>
{
    private readonly ITempDataProvider _tempDataProvider;

    public CustomRequirementHandler(ITempDataProvider tempDataProvider)
    {
        _tempDataProvider = tempDataProvider;
    }

    protected override Task HandleRequirementAsync(AuthorizationHandlerContext context, CustomRequirement requirement)
    {
        ///////
        //Your logic
        ///////
        context.Fail();


        if (context.HasFailed && context.Resource is AuthorizationFilterContext mvcContext)
        {
            _tempDataProvider.SaveTempData(mvcContext.HttpContext, new Dictionary<string, object>() {  { "message","alertmessage "+DateTime.Now } });
        }

        return Task.CompletedTask;
    }
}