Support all ProblemDetail types in the multi response types for generating swagger docs MinimalApi

[mehdihadeli]

Hi,
I want to create an api with multiple result types with using TypedResults, but seems, .net core 7 only supports ValidationProblem for generating swagger metadata automatically and ProblemHttpResult type doesn't generate any swagger metadata. Maybe we need to declare dedicated problem types like ValidationProblem for others, like InternalProbelm, UnAuthorizedProblem, ...

      async Task<Results<CreatedAtRoute<CreateProductResponse>, ProblemHttpResult>>
            Handle([AsParameters] CreateProductRequestParameters requestInput)
        {
            ///...
            return TypedResults.CreatedAtRoute(
                new CreateProductResponse(result.Id),
                "GetProductById",
                new {id = result.Id});
        }

I had to handle it manually for myself like this (we have some limitation because ProblemHttpResult is sealed class and I can't inherit from it directly, so I created a HttpProblemResultBase for replacement, also ProducesResponseTypeMetadata was internal, and I had to create a custom one):

public class HttpProblemResultBase :
    IResult,
    IStatusCodeHttpResult,
    IContentTypeHttpResult,
    IValueHttpResult,
    IEndpointMetadataProvider,
    IValueHttpResult<ProblemDetails>
{
    private readonly ProblemHttpResult _problem;

    public HttpProblemResultBase(
        int statusCode,
        string? title = null,
        string? type = null,
        string? detail = null,
        string? instance = null,
        IDictionary<string, object?>? extensions = null
    )
    {
        _problem = TypedResults.Problem(
            statusCode: statusCode,
            title: title,
            type: type,
            detail: detail,
            instance: instance,
            extensions: extensions);
    }

    public Task ExecuteAsync(HttpContext httpContext)
    {
        return _problem.ExecuteAsync(httpContext);
    }

    public ProblemDetails ProblemDetails => _problem.ProblemDetails;
    public virtual int? StatusCode => _problem.StatusCode;
    public string ContentType => _problem.ContentType;
    object IValueHttpResult.Value => ProblemDetails;
    public ProblemDetails Value => ProblemDetails;

    public static void PopulateMetadata(MethodInfo method, EndpointBuilder builder)
    {
        method.NotNull();
        builder.NotNull();
        builder.Metadata.Add(new ResponseMetadata(StatusCodes.Status500InternalServerError, typeof(ProblemDetails)));
    }
}

public class InternalHttpProblemResult : HttpProblemResultBase
{
    public InternalHttpProblemResult(
        string? title = null,
        string? type = null,
        string? detail = null,
        string? instance = null,
        IDictionary<string, object?>? extensions = null
    ) : base(StatusCodes.Status500InternalServerError, title, type, detail, instance, extensions)
    {
    }
}

public class NotFoundHttpProblemResult : HttpProblemResultBase
{
    public NotFoundHttpProblemResult(
        string? title = null,
        string? type = null,
        string? detail = null,
        string? instance = null,
        IDictionary<string, object?>? extensions = null
    ) : base(StatusCodes.Status404NotFound, title, type, detail, instance, extensions)
    {
    }
}

And my route now should be for generating swagger metadata for problems automatically:

      async Task<Results<CreatedAtRoute<CreateProductResponse>, UnAuthorizedHttpProblemResult, ValidationProblem>>
            Handle([AsParameters] CreateProductRequestParameters requestInput)
        {
            ///...
            return TypedResults.CreatedAtRoute(
                new CreateProductResponse(result.Id),
                "GetProductById",
                new {id = result.Id});
        }

[SteveSandersonMS]

Moving to area-web-frameworks. @adityamandaleeka does this look like it should go to your team?

[adityamandaleeka]

Yup. cc @mitchdenny @captainsafia

[mitchdenny]

@captainsafia assigning this one to you since you are more familiar with the interplay with Swagger.

[mehdihadeli]

Can I contribute for this?

[mitchdenny]

@mehdihadeli is you would like to propose a change to the public API of ASP.NET Core consider submitting an issue using the following template so that we can run it through the review process.

https://github.com/dotnet/aspnetcore/issues/new?assignees=&labels=api-suggestion&template=30_api_proposal.md&title=

If you prefer you can update the description of the issue above with the template so that we don't lose the context of this conversation. Getting the API changes reviewed is the first step to make sure you don't waste any time working on API changes that may not be approved.