Add exception property to the problem details context

[bjornen77]

Background and Motivation

If an application is configured to generate problem details it would be good, if an exception occurs in the application, that the original exception can be retreived directly on the problem details context. The exception information can be used to customize the problem details when using the CustomizeProblemDetails functionality. The original exception can already be retreived using the IExceptionHandlerFeature, but having the exception directly on the context will be easier and more straight forward to use.

The exception property should be set when the problem details context is written from the built-in exception handler middlewares.

Proposed API

namespace Microsoft.AspNetCore.Http;

public class ProblemDetailsContext
{
+   public Exception? Exception { get; init; }
}

Usage Examples

builder.Services.AddProblemDetails(configure =>
    configure.CustomizeProblemDetails = (context) =>
    {
        if (context.Exception is not null)
        {
            // Customize problem details with information from exception.
        }
    }
);

Alternative Designs

N/A

Risks

None that I am aware of.

[bjornen77]

#47554 (review)

@captainsafia @JamesNK

[ghost]

Thank you for submitting this for API review. This will be reviewed by @dotnet/aspnet-api-review at the next meeting of the ASP.NET Core API Review group. Please ensure you take a look at the API review process documentation and ensure that:

• The PR contains changes to the reference-assembly that describe the API change. Or, you have included a snippet of reference-assembly-style code that illustrates the API change.
• The PR describes the impact to users, both positive (useful new APIs) and negative (breaking changes).
• Someone is assigned to "champion" this change in the meeting, and they understand the impact and design of the change.

[captainsafia]

Thanks! This will go through API review before implementation.

@brunolins16 Do you have any insights that might guide the implementation/API review?

[BrennanConroy]

API Review Notes:

• Who is setting the exception?
  • We would be in DeveloperException page etc.
• The Exception won't be written by our implementations of IProblemDetailsWriter
  • Would be up to the user to put the exception in Extensions in CustomizeProblemDetails if they want that

API Approved!

namespace Microsoft.AspNetCore.Http;

public sealed class ProblemDetailsContext
{
+   public Exception? Exception { get; init; }
}

[brunolins16]

Thanks! This will go through API review before implementation.

@brunolins16 Do you have any insights that might guide the implementation/API review?

Sorry for late response.I like the idea and I am glad that the api is already approved. This will also useful for IProblemDetailsWrtier implementation.