Why is impossible to add interceptors in a generic way and make the scoped service provider resolve them?

[luizfbicalho]

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I have this code in an aspire project

        builder.AddSqlServerDbContext<ModelContext>("sqldb-model", configureDbContextOptions: (options) =>
        {
            options.UseLazyLoadingProxies()
                .ReplaceService<ILazyLoader, EnableDisableLazyLoader>()
                .AddInterceptors(
                    provider.GetRequiredService<ValidateSaveChangesInterceptor>(),
                    provider.GetRequiredService<ServiceLoggerSaveChangesInterceptor<ModelContext>>()
                );
        });

see that I don't have the service provider in the method, i already asked the aspire team about it

dotnet/aspire#7020

and I would like to use a code like this

        builder.AddSqlServerDbContext<ModelContext>("sqldb-model", configureDbContextOptions: (options) =>
        {
            options.UseLazyLoadingProxies()
                .ReplaceService<ILazyLoader, EnableDisableLazyLoader>()
                .AddInterceptor<ValidateSaveChangesInterceptor>()
                .AddInterceptor<ServiceLoggerSaveChangesInterceptor<ModelContext>>()
        });

UPDATE

I added this code to my DbContext

protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
 {
     base.OnConfiguring(optionsBuilder);
     optionsBuilder.AddInterceptors(
         provider.GetRequiredService<ValidateSaveChangesInterceptor>(),
         provider.GetRequiredService<ServiceLoggerSaveChangesInterceptor<ModelContext>>()
     );
 }

and added the IServiceProvider to the constructor, thi have two issues for me, one is that I can't configure outside of the the dbcontext

and the other is that the DbContextHealthCheck somehow is using the root service provider and I got this error

Cannot resolve scoped service 'MC.EntityFramework.Extensions.Interceptors.ValidateSaveChangesInterceptor' from root provider.

   at Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions.GetRequiredService(IServiceProvider provider, Type serviceType)
   at Microsoft.Extensions.DependencyInjection.ServiceProviderServiceExtensions.GetRequiredService[T](IServiceProvider provider)
   at Model.Models.ModelContext.OnConfiguring(DbContextOptionsBuilder optionsBuilder) in C:\\ProjetosGIT\\Model\\Models\\ModelContext.cs:line 14
   at Microsoft.EntityFrameworkCore.DbContext.get_ContextServices()
   at Microsoft.EntityFrameworkCore.DbContext.Microsoft.EntityFrameworkCore.Infrastructure.IInfrastructure<System.IServiceProvider>.get_Instance()
   at Microsoft.EntityFrameworkCore.Infrastructure.Internal.InfrastructureExtensions.GetService(IInfrastructure`1 accessor, Type serviceType)
   at Microsoft.Extensions.Diagnostics.HealthChecks.DbContextHealthCheck`1.CheckHealthAsync(HealthCheckContext context, CancellationToken cancellationToken)

Include provider and version information

EF Core version: 9
Database provider: Microsoft.EntityFrameworkCore.SqlServer
Target framework: .NET 9.0

[WeihanLi]

Where is the provider from in the sample code?

When trying to register an interceptor from dependency injection, you could use the AddDbContext override to register a scoped interceptor from the DI

services.AddScoped<ValidateSaveChangesInterceptor>();
services.AddDbContext<ModelContext>((provider, options) =>
{
    options.AddInterceptors(provider.GetRequiredService<ValidateSaveChangesInterceptor>());
    options.UseSqlite(sqlLiteConnectionString);
})

may relate to #33813

[luizfbicalho]

But if I use .net aspire the method doesn't have the service provider parameter, I just added an issue there asking for that

[WeihanLi]

Oh sorry I missed that

[luizfbicalho]

Oh sorry I missed that

No problem

I think that the .AddInterceptor() could be a good alternative, I'm not sure internally how would warp this, but I imagine that a Keyed ServiceProvider by the DbContext type could be a good solution

It would also help to add interceptors to all dbcontexts at once

[WeihanLi]

maybe this could help

public static IServiceCollection AddDbContextInterceptor<TContext, TInterceptor>(
    this IServiceCollection services,
    ServiceLifetime optionsLifetime = ServiceLifetime.Scoped
    )
    where TContext : DbContext
    where TInterceptor : IInterceptor
{
    Action<IServiceProvider, DbContextOptionsBuilder> optionsAction = (sp, builder) =>
    {
        builder.AddInterceptors(sp.GetRequiredService<TInterceptor>());
    };
    services.Add(ServiceDescriptor.Describe(typeof(TInterceptor), typeof(TInterceptor), optionsLifetime));
    services.Add(ServiceDescriptor.Describe(typeof(IDbContextOptionsConfiguration<TContext>), _ => 
        new DbContextOptionsConfiguration<TContext>(optionsAction), optionsLifetime));
    return services;
}

[luizfbicalho]

Thanks a lot, I'll try it.

Any chance of this code becoming part of EF Core?

[WeihanLi]

Any chance of this code becoming part of EF Core?

Would need API review from the team @ajcvickers @roji

[luizfbicalho]

I tested it now, it's working fine,Ill keep it on my code for now, let's see if @ajcvickers likes it