Where does Razor engine search for View file

Wagner

• Linqpad version 6.7.5
• Basic AspNetCore Mvc snippet code

void Main()
{
    Directory.SetCurrentDirectory(Path.GetDirectoryName(Util.CurrentQueryPath));
    Host.CreateDefaultBuilder()
        .ConfigureWebHostDefaults(builder => builder.ConfigureServices(services=>services.AddControllersWithViews())
            .Configure(app=>app.UseRouting().UseEndpoints(endpoint=>endpoint.MapControllers())))
        .Build()
        .Run();
}

public class HomeController : Controller
{
    [HttpGet("/")]
    public ViewResult Index()
    {
        return View();
    }
}

• The following error

info: Microsoft.AspNetCore.Mvc.Infrastructure.ControllerActionInvoker[2]
      Executed action HomeController.Index (LINQPadQuery) in 110.6171ms
info: Microsoft.AspNetCore.Routing.EndpointMiddleware[1]
      Executed endpoint 'HomeController.Index (LINQPadQuery)'
fail: Microsoft.AspNetCore.Server.Kestrel[13]
      Connection id "0HLUJEGPERA0S", Request id "0HLUJEGPERA0S:00000001": An unhandled exception was thrown by the application.
System.InvalidOperationException: The view 'Index' was not found. The following locations were searched:
/Views/Home/Index.cshtml
/Views/Shared/Index.cshtml

My question is where I should put index.cshtml file?

JoeAlbahari

You need to do two things to make this work:

• call builder.UseContentRoot to tell MVC where the base folder is (the application base from which resolves the views\home\ folder)

• call services.AddRazorPages().AddRazorRuntimeCompilation to set up Razor runtime compilation:

  Host.CreateDefaultBuilder()
      .ConfigureWebHostDefaults (builder =>
      {
          builder.UseContentRoot (@"your base folder");
          builder.ConfigureServices (services =>
          {
              services.AddRazorPages().AddRazorRuntimeCompilation (sa =>
                  Util.Framework.GetReferenceAssemblies (true)
                      .Prepend (GetType().Assembly.Location)
                      .ToList()
                      .ForEach (sa.AdditionalReferencePaths.Add));
              services.AddControllersWithViews();
          })
          .Configure (app => app.UseRouting().UseEndpoints (endpoint => endpoint.MapControllers()));
      })
      .Build()
      .Run();  
  

Here are the extra namespace imports that you need:

Microsoft.AspNetCore.Builder
Microsoft.AspNetCore.Hosting
Microsoft.AspNetCore.Mvc
Microsoft.Extensions.DependencyInjection
Microsoft.Extensions.Hosting

You will also need to add the following NuGet package:

Microsoft.AspNetCore.Mvc.Razor.RuntimeCompilation

Note that right now, the call to Util.Framework.GetReferenceAssemblies (true) will not compile because this overload (that accepts a Boolean parameter to indicate that ASP.NET reference assemblies are required) has not yet been released in a beta. A beta with feature will be available within a few days.

Wagner

Thanks for the quickly reply. I am looking forward for the new release.

Wagner

I have tried the new version 6.8.1. Now the error moves to Microsoft.AspNetCore.Razor.Runtime.

fail: Microsoft.AspNetCore.Server.Kestrel[13]
      Connection id "0HLUSTVQ934JD", Request id "0HLUSTVQ934JD:00000001": An unhandled exception was thrown by the application.
System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.AspNetCore.Razor.Runtime, Version=3.1.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'. The system cannot find the file specified.
File name: 'Microsoft.AspNetCore.Razor.Runtime, Version=3.1.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'
   at System.ModuleHandle.ResolveTypeHandleInternal(RuntimeModule module, Int32 typeToken, RuntimeTypeHandle[] typeInstantiationContext, RuntimeTypeHandle[] methodInstantiationContext)
   at System.Reflection.RuntimeModule.ResolveType(Int32 metadataToken, Type[] genericTypeArguments, Type[] genericMethodArguments)
   at System.Reflection.CustomAttribute.FilterCustomAttributeRecord(MetadataToken caCtorToken, MetadataImport& scope, RuntimeModule decoratedModule, MetadataToken decoratedToken, RuntimeType attributeFilterType, Boolean mustBeInheritable, ListBuilder`1& derivedAttributes, RuntimeType& attributeType, IRuntimeMethodInfo& ctor, Boolean& ctorHasParameters, Boolean& isVarArg)
   at System.Reflection.CustomAttribute.AddCustomAttributes(ListBuilder`1& attributes, RuntimeModule decoratedModule, Int32 decoratedMetadataToken, RuntimeType attributeFilterType, Boolean mustBeInheritable, ListBuilder`1 derivedAttributes)
   at System.Reflection.CustomAttribute.GetCustomAttributes(RuntimeModule decoratedModule, Int32 decoratedMetadataToken, Int32 pcaCount, RuntimeType attributeFilterType)
   at System.Reflection.CustomAttribute.GetCustomAttributes(RuntimeAssembly assembly, RuntimeType caType)
   at System.Reflection.RuntimeAssembly.GetCustomAttributes(Type attributeType, Boolean inherit)
   at System.Attribute.GetCustomAttributes(Assembly element, Type attributeType, Boolean inherit)
   at System.Reflection.CustomAttributeExtensions.GetCustomAttributes[T](Assembly element)
   at Microsoft.AspNetCore.Razor.Hosting.RazorCompiledItemLoader.LoadAttributes(Assembly assembly)
   at Microsoft.AspNetCore.Razor.Hosting.RazorCompiledItemLoader.LoadItems(Assembly assembly)
   at Microsoft.AspNetCore.Mvc.Razor.RuntimeCompilation.RuntimeViewCompiler.CompileAndEmit(String relativePath)
   at Microsoft.AspNetCore.Mvc.Razor.RuntimeCompilation.RuntimeViewCompiler.OnCacheMiss(String normalizedPath)
--- End of stack trace from previous location where exception was thrown ---
   at Microsoft.AspNetCore.Mvc.Razor.Compilation.DefaultRazorPageFactoryProvider.CreateFactory(String relativePath)
   at Microsoft.AspNetCore.Mvc.Razor.RazorViewEngine.CreateCacheResult(HashSet`1 expirationTokens, String relativePath, Boolean isMainPage)
   at Microsoft.AspNetCore.Mvc.Razor.RazorViewEngine.OnCacheMiss(ViewLocationExpanderContext expanderContext, ViewLocationCacheKey cacheKey)
   at Microsoft.AspNetCore.Mvc.Razor.RazorViewEngine.LocatePageFromViewLocations(ActionContext actionContext, String pageName, Boolean isMainPage)
   at Microsoft.AspNetCore.Mvc.Razor.RazorViewEngine.FindView(ActionContext context, String viewName, Boolean isMainPage)
   at Microsoft.AspNetCore.Mvc.ViewEngines.CompositeViewEngine.FindView(ActionContext context, String viewName, Boolean isMainPage)
   at Microsoft.AspNetCore.Mvc.ViewFeatures.ViewResultExecutor.FindView(ActionContext actionContext, ViewResult viewResult)
   at Microsoft.AspNetCore.Mvc.ViewFeatures.ViewResultExecutor.ExecuteAsync(ActionContext context, ViewResult result)
   at Microsoft.AspNetCore.Mvc.ViewResult.ExecuteResultAsync(ActionContext context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextResultFilterAsync>g__Awaited|29_0[TFilter,TFilterAsync](ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResultExecutedContextSealed context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.ResultNext[TFilter,TFilterAsync](State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeResultFilters()
--- End of stack trace from previous location where exception was thrown ---
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeNextResourceFilter>g__Awaited|24_0(ResourceInvoker invoker, Task lastTask, State next, Scope scope, Object state, Boolean isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Rethrow(ResourceExecutedContextSealed context)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.Next(State& next, Scope& scope, Object& state, Boolean& isCompleted)
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.InvokeFilterPipelineAsync()
--- End of stack trace from previous location where exception was thrown ---
   at Microsoft.AspNetCore.Mvc.Infrastructure.ResourceInvoker.<InvokeAsync>g__Logged|17_1(ResourceInvoker invoker)
   at Microsoft.AspNetCore.Routing.EndpointMiddleware.<Invoke>g__AwaitRequestTask|6_0(Endpoint endpoint, Task requestTask, ILogger logger)
   at Microsoft.AspNetCore.Server.Kestrel.Core.Internal.Http.HttpProtocol.ProcessRequests[TContext](IHttpApplication`1 application)

JoeAlbahari

In Query Properties (F4), have you ticked the checkbox Reference ASP.NET Core assemblies?

The only NuGet package you should need is Microsoft.AspNetCore.Mvc.Razor.RuntimeCompilation.

Wagner

Yes. Here is the header for the linq

<Query Kind="Program">
  <NuGetReference>Microsoft.AspNetCore.Mvc.Razor.RuntimeCompilation</NuGetReference>
  <Namespace>Microsoft.AspNetCore</Namespace>
  <Namespace>Microsoft.AspNetCore.Builder</Namespace>
  <Namespace>Microsoft.AspNetCore.Hosting</Namespace>
  <Namespace>Microsoft.AspNetCore.Http</Namespace>
  <Namespace>Microsoft.AspNetCore.Mvc</Namespace>
  <Namespace>Microsoft.Extensions.DependencyInjection</Namespace>
  <Namespace>Microsoft.Extensions.Hosting</Namespace>
  <Namespace>Microsoft.Extensions.Logging</Namespace>
  <IncludeAspNet>true</IncludeAspNet>
</Query>

Still the error from Kestrel

fail: Microsoft.AspNetCore.Server.Kestrel[13]
      Connection id "0HLV5GRQS3EK2", Request id "0HLV5GRQS3EK2:00000001": An unhandled exception was thrown by the application.
System.IO.FileNotFoundException: Could not load file or assembly 'Microsoft.AspNetCore.Razor.Runtime, Version=3.1.0.0, Culture=neutral, PublicKeyToken=adb9793829ddae60'. The system cannot find the file specified.

JoeAlbahari

I've identified the problem and will aim to get a fix out in the next day or two.

JoeAlbahari

The ALC issue with ASP.NET assemblies has been fixed in 6.8.1:
https://www.linqpad.net/LINQPad6.aspx#beta

Let me know how you get along.

Wagner

Terrific. It works now. But the new beta version is 6.8.2 NOT 6.8.1. I think this is just your typo.

JoeAlbahari

Great. Let me know if there any more glitches. It would be good to make LINQPad robust in this scenario.

sdflysha

@JoeAlbahari I have no idea but my razor engine view file seems not working:

I'm using latest 6.8.2 version, just tell me what's wrong