InvalidOperationException at startup

[DemiMarie]

When running my code, I get a System.InvalidOperationException at startup. How can I debug this?

[DemiMarie]

Partial stack trace:

Exception has occurred: CLR/System.InvalidOperationException
An exception of type 'System.InvalidOperationException' occurred in Microsoft.Extensions.DependencyInjection.dll but was not handled in user code: 'Cannot resolve scoped service 'React.AspNet.HttpContextLifetimeProvider+PerRequestRegistrations' from root provider.'
  at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteVisitor.ValidateResolution(Type serviceType, IServiceScope scope, IServiceScope rootScope)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.ServiceProviderEngine.GetService(Type serviceType, IServiceScope scope)

(some frames skipped)

   at React.AspNet.ReactBuilderExtensions.EnsureServicesRegistered(IApplicationBuilder app)
   at React.AspNet.ReactBuilderExtensions.UseReact(IApplicationBuilder app, Action`1 configure, BabelFileOptions fileOptions)

[nightblade9]

I, too, get this with ASP.NET Core 2.1. This is similar to this issue, which talks about (and fixes) ASP.NET Core 2.0; the proposed fix doesn't work on 2.1; you get this error instead:

InvalidOperationException: The 'Configure' method in the type 'ReactDemo.Startup' must have a return type of 'Void'.

Microsoft.AspNetCore.Hosting.Internal.StartupLoader.FindMethod(Type startupType, string methodName, string environmentName, Type returnType, bool required)

[DemiMarie]

Do you know any workarounds?

…

On Thu, Sep 27, 2018, 4:30 PM nightblade9 ***@***.***> wrote: I, too, get this with ASP.NET Core 2.1. This is similar to this issue <#433>, which talks about (and fixes) ASP.NET Core 2.0; the proposed fix doesn't work on 2.1; you get this error instead: InvalidOperationException: The 'Configure' method in the type 'ReactDemo.Startup' must have a return type of 'Void'. Microsoft.AspNetCore.Hosting.Internal.StartupLoader.FindMethod(Type startupType, string methodName, string environmentName, Type returnType, bool required) — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#601 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AGGWB6ISeSowDL-oqFDc2moctAltQlkWks5ufTVxgaJpZM4W46OX> .

[nightblade9]

@DemiMarie no, I haven't figured out any work-around yet. I tried installing the .NET Core 2.0 SDK, hoping Visual Studio would use that instead, but it doesn't; I get a compile-time error when I downgrade my project to 2.0, about some library that's .NET Core 2.1, but not referenced in NuGet etc.

[dustinsoftware]

Thanks for reporting, I’ll give this a look

…

On Thu, Sep 27, 2018 at 18:48, nightblade9 ***@***.***> wrote: @DemiMarie <https://github.com/DemiMarie> no, I haven't figured out any work-around yet. I tried installing the .NET Core 2.0 SDK, hoping Visual Studio would use that instead, but it doesn't; I get a compile-time error when I downgrade my project to 2.0, about some library that's .NET Core 2.1, but not referenced in NuGet etc. — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#601 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AA5hFkXRSGA3DMDelPijyo4xSSU9HHE9ks5ufYAEgaJpZM4W46OX> .

[jbrinkle]

@DemiMarie @nightblade9
I got the same behavior while starting a brand new Core 2.1 AspNet MVC web app.
However, I also followed the migratory steps from Core 2.0 to 2.1 on the tutorial project and it worked. I don't know why, but you may be able to reference the same page in your efforts to reverse-migrate back to 2.0

[nightblade9]

Interestingly,Visual Studio now includes a template for a "React" app. I don't think it's ReactJS.NET, I think it's just vanilla React; that template seems to run fine.

[nightblade9]

I did some more digging with the .NET Core 2.1 template.

If you add this code to the ConfigureServices method, not with Configure as the tutorial specifies:

services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
services.AddReact();

You get an exception on the app.UseReact(config => line. The exception is:

InvalidOperationException: Cannot resolve scoped service 'React.AspNet.HttpContextLifetimeProvider+PerRequestRegistrations' from root provider.

It looks like HttpContextLifetimeProvider is an internal class defined here, and this is something AddReact is supposed to add.

I added debugger points to make sure AddReact is being hit, and it is.

Can someone from the ReactJS.NET core team help?

[dustinsoftware]

I just tried to update one of the samples to .NET Core 2.1 and had no problems..

Can you give this sample a look? I don't have time right now to investigate further. https://github.com/reactjs/React.NET/blob/master/src/React.Sample.CoreMvc/React.Sample.CoreMvc.csproj

[DaniilSokolyuk]

I think because

React.NET/src/React.Sample.CoreMvc/Startup.cs

Line 37 in fe72ea9

public IServiceProvider ConfigureServices(IServiceCollection services)

returns IServiceProvider, but! in default template it returns void.
You can disable DI Scope validation and fix this problem, in program.cs

public static IWebHostBuilder CreateWebHostBuilder(string[] args) =>
            WebHost.CreateDefaultBuilder(args)
                .UseDefaultServiceProvider(options => options.ValidateScopes = false) // << add this line
                .UseStartup<Startup>();

[dustinsoftware]

@DaniilSokolyuk is correct, returning an instance of IServiceProvider is necessary. I'm not sure why this is the case, and it appears the docs are out of date. We may need to change how we're building a service provider since all the .NET Core docs indicate that ConfigureServices have no return value.

[dustinsoftware]

Huh, looks like the problem is resolved by removing the EnsureServicesRegistered check in ReactBuilderExtensions. I'll do a little bit more testing to ensure we can remove it safely.

[dustinsoftware]

This has been fixed in the latest release of ReactJS.NET.