c#asp.net-core dependency-injection asp.net-core-webapi asp.net-core-8

How to register System.TimeProvider implementation?

I have an issue in the Program.cs class of a WebAPI project in .NET 8.0. I'm following an ASP.NET course that uses .NET Core 3.1, but I've decided to try to upgrade it to .NET 8. I'm working with user registration in ASP.NET.

I have this code in Program.cs:

using Aplicacion.Cursos;
using Dominio;
using FluentValidation;
using FluentValidation.AspNetCore;
using MediatR;
using Microsoft.AspNetCore.Authentication;
using Microsoft.AspNetCore.Identity;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Design;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.DependencyInjection.Extensions;
using Microsoft.OpenApi.Models;
using Persistencia;
using System;
using System.Reflection;
using WebAPI.Middleware;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.
builder.Services.AddControllers();
builder.Services.AddFluentValidationAutoValidation();
builder.Services.AddFluentValidationClientsideAdapters();
builder.Services.AddValidatorsFromAssemblyContaining<Nuevo>();
//builder.Services.AddValidatorsFromAssemblyContaining<Editar>();

//configuración del contexto de la base de datos
builder.Services.AddDbContext<CursosOnlineContext>(opt => 
    opt.UseSqlServer(builder.Configuration.GetConnectionString("conexionSQLServer")));

//configuración core identity
var identityCoreUsuario = builder.Services.AddIdentityCore<Usuario>();
var identityBuilder = new IdentityBuilder(identityCoreUsuario.UserType, identityCoreUsuario.Services);
identityBuilder.AddEntityFrameworkStores<CursosOnlineContext>();
identityBuilder.AddSignInManager<SignInManager<Usuario>>();

builder.Services.AddSingleton<ISystemClock, SystemClock>();


//para utilizar el manejador
builder.Services.AddMediatR(cfg => cfg.RegisterServicesFromAssembly(typeof(Consulta.Manejador).Assembly));

// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen(c =>
{
    c.SwaggerDoc("v1", new OpenApiInfo { Title = "API Proyecto Core", Version = "v1" });

    c.CustomSchemaIds(type => type.FullName?.Replace("+", "."));
});


var app = builder.Build();

// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
    app.UseSwagger();
    app.UseSwaggerUI();

}

using (var ambiente = app.Services.CreateScope())
{
    var services = ambiente.ServiceProvider;

    try
    {
        var userManager = services.GetRequiredService<UserManager<Usuario>>();
        var context = services.GetRequiredService<CursosOnlineContext>();
        context.Database.Migrate();
        DataPrueba.InsertarData(context, userManager).Wait();
    }
    catch(Exception)
    {
        var logging = services.GetRequiredService<ILogger<Program>>();
        logging.LogError("Ha ocurrido un error en la migración");
    }

   
}


app.UseHttpsRedirection();

app.UseAuthorization();

app.MapControllers();

app.UseMiddleware<ManejadorErrorMiddleware>();

app.Run();

And I'm getting the following error:

Unhandled exception. System.AggregateException: Some services are not able to be constructed (Error while validating the service descriptor 'ServiceType: Microsoft.AspNetCore.Identity.ISecurityStampValidator Lifetime: Scoped ImplementationType: Microsoft.AspNetCore.Identity.SecurityStampValidator`1[Dominio.Usuario]': Unable to resolve service for type 'System.TimeProvider' while attempting to activate 'Microsoft.AspNetCore.Identity.IdentityBuilderExtensions+PostConfigureSecurityStampValidatorOptions'.) (Error while validating the service descriptor 'ServiceType: Microsoft.AspNetCore.Identity.ITwoFactorSecurityStampValidator Lifetime: Scoped ImplementationType: Microsoft.AspNetCore.Identity.TwoFactorSecurityStampValidator`1[Dominio.Usuario]': Unable to resolve service for type 'System.TimeProvider' while attempting to activate 'Microsoft.AspNetCore.Identity.IdentityBuilderExtensions+PostConfigureSecurityStampValidatorOptions'.) (Error while validating the service descriptor 'ServiceType: Microsoft.Extensions.Options.IPostConfigureOptions`1[Microsoft.AspNetCore.Identity.SecurityStampValidatorOptions] Lifetime: Singleton ImplementationType: Microsoft.AspNetCore.Identity.IdentityBuilderExtensions+PostConfigureSecurityStampValidatorOptions': Unable to resolve service for type 'System.TimeProvider' while attempting to activate 'Microsoft.AspNetCore.Identity.IdentityBuilderExtensions+PostConfigureSecurityStampValidatorOptions'.) ---> System.InvalidOperationException: Error while validating the service descriptor 'ServiceType: Microsoft.AspNetCore.Identity.ISecurityStampValidator Lifetime: Scoped ImplementationType: Microsoft.AspNetCore.Identity.SecurityStampValidator`1[Dominio.Usuario]': Unable to resolve service for type 'System.TimeProvider' while attempting to activate 'Microsoft.AspNetCore.Identity.IdentityBuilderExtensions+PostConfigureSecurityStampValidatorOptions'. ---> System.InvalidOperationException: Unable to resolve service for type 'System.TimeProvider' while attempting to activate 'Microsoft.AspNetCore.Identity.IdentityBuilderExtensions+PostConfigureSecurityStampValidatorOptions'.

   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateArgumentCallSites(ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain, ParameterInfo[] parameters, Boolean throwIfCallSiteNotFound)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateConstructorCallSite(ResultCache lifetime, ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateExact(ServiceDescriptor descriptor, ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain, Int32 slot)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateEnumerable(ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateCallSite(ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateArgumentCallSites(ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain, ParameterInfo[] parameters, Boolean throwIfCallSiteNotFound)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateConstructorCallSite(ResultCache lifetime, ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateOpenGeneric(ServiceDescriptor descriptor, ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain, Int32 slot, Boolean throwOnConstraintViolation)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateOpenGeneric(ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateCallSite(ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateArgumentCallSites(ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain, ParameterInfo[] parameters, Boolean throwIfCallSiteNotFound)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateConstructorCallSite(ResultCache lifetime, ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateOpenGeneric(ServiceDescriptor descriptor, ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain, Int32 slot, Boolean throwOnConstraintViolation)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateOpenGeneric(ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateCallSite(ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateArgumentCallSites(ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain, ParameterInfo[] parameters, Boolean throwIfCallSiteNotFound)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateConstructorCallSite(ResultCache lifetime, ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateExact(ServiceDescriptor descriptor, ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain, Int32 slot)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.GetCallSite(ServiceDescriptor serviceDescriptor, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceProvider.ValidateService(ServiceDescriptor descriptor)
   --- End of inner exception stack trace ---
   at Microsoft.Extensions.DependencyInjection.ServiceProvider.ValidateService(ServiceDescriptor descriptor)
   at Microsoft.Extensions.DependencyInjection.ServiceProvider..ctor(ICollection`1 serviceDescriptors, ServiceProviderOptions options)
   --- End of inner exception stack trace ---
   at Microsoft.Extensions.DependencyInjection.ServiceProvider..ctor(ICollection`1 serviceDescriptors, ServiceProviderOptions options)
   at Microsoft.Extensions.DependencyInjection.ServiceCollectionContainerBuilderExtensions.BuildServiceProvider(IServiceCollection services, ServiceProviderOptions options)
   at Microsoft.Extensions.Hosting.HostApplicationBuilder.Build()
   at Microsoft.AspNetCore.Builder.WebApplicationBuilder.Build()
   at Program.<Main>$(String[] args) in C:\Users\Nicolas\Documents\ProyectoCore\WebAPI\Program.cs:line 54
 ---> (Inner Exception #1) System.InvalidOperationException: Error while validating the service descriptor 'ServiceType: Microsoft.AspNetCore.Identity.ITwoFactorSecurityStampValidator Lifetime: Scoped ImplementationType: Microsoft.AspNetCore.Identity.TwoFactorSecurityStampValidator`1[Dominio.Usuario]': Unable to resolve service for type 'System.TimeProvider' while attempting to activate 'Microsoft.AspNetCore.Identity.IdentityBuilderExtensions+PostConfigureSecurityStampValidatorOptions'.
 ---> System.InvalidOperationException: Unable to resolve service for type 'System.TimeProvider' while attempting to activate 'Microsoft.AspNetCore.Identity.IdentityBuilderExtensions+PostConfigureSecurityStampValidatorOptions'.
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateArgumentCallSites(ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain, ParameterInfo[] parameters, Boolean throwIfCallSiteNotFound)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateConstructorCallSite(ResultCache lifetime, ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateExact(ServiceDescriptor descriptor, ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain, Int32 slot)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateEnumerable(ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateCallSite(ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateArgumentCallSites(ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain, ParameterInfo[] parameters, Boolean throwIfCallSiteNotFound)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateConstructorCallSite(ResultCache lifetime, ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateOpenGeneric(ServiceDescriptor descriptor, ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain, Int32 slot, Boolean throwOnConstraintViolation)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateOpenGeneric(ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateCallSite(ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateArgumentCallSites(ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain, ParameterInfo[] parameters, Boolean throwIfCallSiteNotFound)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateConstructorCallSite(ResultCache lifetime, ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateOpenGeneric(ServiceDescriptor descriptor, ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain, Int32 slot, Boolean throwOnConstraintViolation)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateOpenGeneric(ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateCallSite(ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateArgumentCallSites(ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain, ParameterInfo[] parameters, Boolean throwIfCallSiteNotFound)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateConstructorCallSite(ResultCache lifetime, ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateExact(ServiceDescriptor descriptor, ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain, Int32 slot)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.GetCallSite(ServiceDescriptor serviceDescriptor, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceProvider.ValidateService(ServiceDescriptor descriptor)
   --- End of inner exception stack trace ---
   at Microsoft.Extensions.DependencyInjection.ServiceProvider.ValidateService(ServiceDescriptor descriptor)
   at Microsoft.Extensions.DependencyInjection.ServiceProvider..ctor(ICollection`1 serviceDescriptors, ServiceProviderOptions options)<---

 ---> (Inner Exception #2) System.InvalidOperationException: Error while validating the service descriptor 'ServiceType: Microsoft.Extensions.Options.IPostConfigureOptions`1[Microsoft.AspNetCore.Identity.SecurityStampValidatorOptions] Lifetime: Singleton ImplementationType: Microsoft.AspNetCore.Identity.IdentityBuilderExtensions+PostConfigureSecurityStampValidatorOptions': Unable to resolve service for type 'System.TimeProvider' while attempting to activate 'Microsoft.AspNetCore.Identity.IdentityBuilderExtensions+PostConfigureSecurityStampValidatorOptions'.
 ---> System.InvalidOperationException: Unable to resolve service for type 'System.TimeProvider' while attempting to activate 'Microsoft.AspNetCore.Identity.IdentityBuilderExtensions+PostConfigureSecurityStampValidatorOptions'.
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateArgumentCallSites(ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain, ParameterInfo[] parameters, Boolean throwIfCallSiteNotFound)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.CreateConstructorCallSite(ResultCache lifetime, ServiceIdentifier serviceIdentifier, Type implementationType, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.TryCreateExact(ServiceDescriptor descriptor, ServiceIdentifier serviceIdentifier, CallSiteChain callSiteChain, Int32 slot)
   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.GetCallSite(ServiceDescriptor serviceDescriptor, CallSiteChain callSiteChain)
   at Microsoft.Extensions.DependencyInjection.ServiceProvider.ValidateService(ServiceDescriptor descriptor)
   --- End of inner exception stack trace ---
   at Microsoft.Extensions.DependencyInjection.ServiceProvider.ValidateService(ServiceDescriptor descriptor)
   at Microsoft.Extensions.DependencyInjection.ServiceProvider..ctor(ICollection`1 serviceDescriptors, ServiceProviderOptions options)<---

I have these warnings:

CS0618  'ISystemClock' está obsoleto: 'Use TimeProvider instead.'   
CS0618  'SystemClock' está obsoleto: 'Use TimeProvider instead.'

I try this:

builder.Services.AddSingleton<TimeProvider>();

But then I get this error:

Unhandled exception. System.ArgumentException: Cannot instantiate implementation type 'System.TimeProvider' for service type 'System.TimeProvider'.

   at Microsoft.Extensions.DependencyInjection.ServiceLookup.CallSiteFactory.Populate()
   at Microsoft.Extensions.DependencyInjection.ServiceProvider..ctor(ICollection`1 serviceDescriptors, ServiceProviderOptions options)
   at Microsoft.Extensions.DependencyInjection.ServiceCollectionContainerBuilderExtensions.BuildServiceProvider(IServiceCollection services, ServiceProviderOptions options)
   at Microsoft.Extensions.Hosting.HostApplicationBuilder.Build()
   at Microsoft.AspNetCore.Builder.WebApplicationBuilder.Build()
   at Program.<Main>$(String[] args) in C:\Users\Nicolas\Documents\ProyectoCore\WebAPI\Program.cs:line 54

How can I implement TimeProvider in this way to make it work?

Solution

If you look at TimeProvider definition, you can see it's an abstract class. Abstract classes cannot be initialized.

But, if you analyze TimeProvider class in greater detail, you'll notice that it provides a static System property:

var provider = TimeProvider.System;

This is a default implementation of TimeProvider. You can use this when registering TimeProvider within service collection:

builder.Services.AddSingleton(TimeProvider.System);