Global filter dependency injection NullReferenceException

[gintarasd-bentley]

Hello, thank you for this project, it's great!

I recently moved from v5.6.2 to v5.7.3, and ran into an exception:

Unhandled exception. System.NullReferenceException: Object reference not set to an instance of an object.
   at ConsoleAppFramework.ConsoleApp.ConsoleAppBuilder.Command0Invoker.BuildFilter() in ...\obj\Debug\net10.0\ConsoleAppFramework\ConsoleAppFramework.ConsoleAppGenerator\ConsoleApp.Builder.g.cs:line 82
   at ConsoleAppFramework.ConsoleApp.ConsoleAppBuilder.Run(String[] args, Boolean startHost, Boolean stopHost, Boolean disposeServiceProvider, CancellationToken cancellationToken) in ...\obj\Debug\net10.0\ConsoleAppFramework\ConsoleAppFramework.ConsoleAppGenerator\ConsoleApp.Builder.Run.g.cs:line 32
   at ConsoleAppFramework.ConsoleApp.ConsoleAppBuilder.Run(String[] args) in ...\obj\Debug\net10.0\ConsoleAppFramework\ConsoleAppFramework.ConsoleAppGenerator\ConsoleApp.Builder.Run.g.cs:line 24
   at Program.<Main>$(String[] args) in ...\Program.cs:line 7

While debugging I found that the ServiceProvider is null when BuildFilter is invoked:

// ConsoleApp.Builder.g.cs
sealed class Command0Invoker(ConsoleAppBuilder builder) : ConsoleAppFilter(null!)
{
    public ConsoleAppFilter BuildFilter()
    {
        var filter0 = new global::MyFilter(this, (global::MyService)ServiceProvider!.GetService(typeof(global::MyService))!);
        return filter0;
    }

    public override Task InvokeAsync(ConsoleAppContext context, CancellationToken cancellationToken)
    {
        return builder.RunCommand0Async(context, cancellationToken);
    }
}

For context, I am using a global filter which depends on a service from DI.

The exception is not thrown when using v5.6.2, or when there is no filter (e.g. comment out the app.UseFilter<> line)

I managed to reproduce this issue in the sample below:

Sample

<Project Sdk="Microsoft.NET.Sdk">
    <PropertyGroup>
        <OutputType>Exe</OutputType>
        <TargetFramework>net10.0</TargetFramework>
        <ImplicitUsings>enable</ImplicitUsings>
        <Nullable>enable</Nullable>
    </PropertyGroup>
    <ItemGroup>
        <FrameworkReference Include="Microsoft.AspNetCore.App"/>
        <PackageReference Include="ConsoleAppFramework" Version="5.7.3"/>
    </ItemGroup>
</Project>

// Program.cs
using ConsoleAppFramework;
using Microsoft.Extensions.DependencyInjection;

var app = ConsoleApp.Create();
app.ConfigureServices(services => services.AddSingleton<MyService>());
app.UseFilter<MyFilter>();
app.Run(["cmd", "test"]);

public class MyService
{
    public void Test() => Console.WriteLine("Test");
}

internal class MyFilter(ConsoleAppFilter next, MyService myService) : ConsoleAppFilter(next)
{
    public override async Task InvokeAsync(ConsoleAppContext context, CancellationToken cancellationToken)
    {
        myService.Test();
        await Next.InvokeAsync(context, cancellationToken);
    }
}

[RegisterCommands("cmd")]
public class MyCommand
{
    [Command("test")]
    public int Test()
    {
        return 1;
    }
}

Let me know if there's anything else I can provide. Also, #88 might be related.

[neuecc]

Thank you!
Because we delayed the ServiceProvider creation to support GlobalFilter, it ended up happening after the filter's constructor injection.
This was an oversight on my part.
I will fix it and add unit tests to prevent this from happening again.

[neuecc]

v 5.7.4 fixed.

[gintarasd-bentley]

That was fast! can confirm it works, thank you