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NullReferenceException in 7.2.0

See original GitHub issue

Hi,

I’m running FV 7.20 in a new ASP.NET Core 2.0 project. I’ve followed the Wiki on wiring FV up to MVC. When I navigate to any screen with an input on it I get a NullReferenceException error.

This happens with all the validators removed. As soon as I add services.AddMvc().AddFluentValidation(); to startup.cs it throws a NullReferenceException: Object reference not set to an instance of an object. FluentValidation.AspNetCore.FluentValidationClientModelValidatorProvider.CreateValidators(ClientValidatorProviderContext context) error.

I installed 7.1.1 in the project and everything works as expected so this looks like it’s isolated to 7.2.0.

Any ideas?

Full stack trace:

FluentValidation.AspNetCore.FluentValidationClientModelValidatorProvider.CreateValidators(ClientValidatorProviderContext context)
Microsoft.AspNetCore.Mvc.ModelBinding.Validation.CompositeClientModelValidatorProvider.CreateValidators(ClientValidatorProviderContext context)
Microsoft.AspNetCore.Mvc.Internal.ClientValidatorCache.GetValidators(ModelMetadata metadata, IClientModelValidatorProvider validatorProvider)
Microsoft.AspNetCore.Mvc.ViewFeatures.DefaultValidationHtmlAttributeProvider.AddValidationAttributes(ViewContext viewContext, ModelExplorer modelExplorer, IDictionary<string, string> attributes)
Microsoft.AspNetCore.Mvc.ViewFeatures.ValidationHtmlAttributeProvider.AddAndTrackValidationAttributes(ViewContext viewContext, ModelExplorer modelExplorer, string expression, IDictionary<string, string> attributes)
Microsoft.AspNetCore.Mvc.ViewFeatures.DefaultHtmlGenerator.AddValidationAttributes(ViewContext viewContext, TagBuilder tagBuilder, ModelExplorer modelExplorer, string expression)
Microsoft.AspNetCore.Mvc.ViewFeatures.DefaultHtmlGenerator.GenerateInput(ViewContext viewContext, InputType inputType, ModelExplorer modelExplorer, string expression, object value, bool useViewData, bool isChecked, bool setId, bool isExplicitValue, string format, IDictionary<string, object> htmlAttributes)
Microsoft.AspNetCore.Mvc.ViewFeatures.DefaultHtmlGenerator.GenerateTextBox(ViewContext viewContext, ModelExplorer modelExplorer, string expression, object value, string format, object htmlAttributes)
Microsoft.AspNetCore.Mvc.TagHelpers.InputTagHelper.GenerateHidden(ModelExplorer modelExplorer)
Microsoft.AspNetCore.Mvc.TagHelpers.InputTagHelper.Process(TagHelperContext context, TagHelperOutput output)
Microsoft.AspNetCore.Razor.TagHelpers.TagHelper.ProcessAsync(TagHelperContext context, TagHelperOutput output)
Microsoft.AspNetCore.Razor.Runtime.TagHelpers.TagHelperRunner+<RunAsync>d__0.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
System.Runtime.CompilerServices.TaskAwaiter.GetResult()
AspNetCore._Views_BankAccounts__Form_cshtml+<ExecuteAsync>d__13.MoveNext() in _Form.cshtml
+
<input asp-for="BankId" />
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Mvc.Razor.RazorView+<RenderPageCoreAsync>d__16.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Mvc.Razor.RazorView+<RenderPageAsync>d__15.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Mvc.Razor.RazorView+<RenderAsync>d__14.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Mvc.ViewFeatures.HtmlHelper+<RenderPartialCoreAsync>d__60.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Mvc.ViewFeatures.HtmlHelper+<PartialAsync>d__57.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Mvc.Rendering.HtmlHelperPartialExtensions.Partial(IHtmlHelper htmlHelper, string partialViewName, object model, ViewDataDictionary viewData)
Microsoft.AspNetCore.Mvc.Rendering.HtmlHelperPartialExtensions.Partial(IHtmlHelper htmlHelper, string partialViewName)
AspNetCore._Views_BankAccounts_Add_cshtml+<<ExecuteAsync>b__14_5>d.MoveNext() in Add.cshtml
+
        @Html.Partial("_Form")
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Razor.Runtime.TagHelpers.TagHelperExecutionContext+<GetChildContentAsync>d__31.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Mvc.TagHelpers.RenderAtEndOfFormTagHelper+<ProcessAsync>d__7.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Razor.Runtime.TagHelpers.TagHelperRunner+<RunAsync>d__0.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
System.Runtime.CompilerServices.TaskAwaiter.GetResult()
AspNetCore._Views_BankAccounts_Add_cshtml+<ExecuteAsync>d__14.MoveNext() in Add.cshtml
+
    ViewData["Title"] = "Add Bank Account";
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Mvc.Razor.RazorView+<RenderPageCoreAsync>d__16.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Mvc.Razor.RazorView+<RenderPageAsync>d__15.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Mvc.Razor.RazorView+<RenderAsync>d__14.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Mvc.ViewFeatures.ViewExecutor+<ExecuteAsync>d__22.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Mvc.ViewFeatures.ViewExecutor+<ExecuteAsync>d__21.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Mvc.ViewResult+<ExecuteResultAsync>d__26.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker+<InvokeResultAsync>d__19.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker+<InvokeNextResultFilterAsync>d__24.MoveNext()
Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.Rethrow(ResultExecutedContext context)
Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.Next(ref State next, ref Scope scope, ref object state, ref bool isCompleted)
Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker+<InvokeNextResourceFilter>d__22.MoveNext()
Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.Rethrow(ResourceExecutedContext context)
Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker.Next(ref State next, ref Scope scope, ref object state, ref bool isCompleted)
Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker+<InvokeFilterPipelineAsync>d__17.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Mvc.Internal.ResourceInvoker+<InvokeAsync>d__15.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Builder.RouterMiddleware+<Invoke>d__4.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Cors.Infrastructure.CorsMiddleware+<Invoke>d__7.MoveNext()
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
System.Runtime.CompilerServices.TaskAwaiter.GetResult()
SomeProject.WebClient.Extensions.Middleware.LoggingMiddleware+<Invoke>d__4.MoveNext() in LoggingMiddleware.cs
+
                await _next(httpContext);
System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task)
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task)
Microsoft.AspNetCore.Diagnostics.DeveloperExceptionPageMiddleware+<Invoke>d__7.MoveNext()

Let me know if you need anything else to investigate.

Regards,

Chris

Issue Analytics

  • State:closed
  • Created 6 years ago
  • Comments:5 (5 by maintainers)

github_iconTop GitHub Comments

3reactions
JeremySkinnercommented, Oct 13, 2017

Perfect, thanks. Looks like an easy fix - just add a registration for IHttpContextAccessor in your application startup routine after the call to AddFluentValidation:

services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();

I already had this in my test projects which was why I wasn’t seeing the problem. For the next release I’ll add a check to see if IHttpContextAccessor is registered and provide a more useful message if it isn’t.

There is a performance hit for having IHttpContextProvider enabled (which is why MVC doesn’t enable it by default, and why I don’t silently register it in AddFluentValidation), but it’s needed for the clientside validation integration. If you don’t want to use the IHttpContextAccessor then you can disable clientside validation:

services.AddMvc().AddFluentValidation(fv => {
	            fv.RegisterValidatorsFromAssemblyContaining<MyValidator>();
	            fv.ConfigureClientsideValidation(enabled: false);
});
0reactions
Chris-ZAcommented, Oct 13, 2017

Disabling client-side validation did the trick!

Thank you very much! 👍

Read more comments on GitHub >

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