Adding Http(Request/Response) extension methods overloads accepting non-generic JsonTypeInfo

[brunolins16]

Background and Motivation

STJ introduced new overloads (dotnet/runtime#77051) with untyped JsonTypeInfo, however, HttpResponse and HttpRequest extension methods only support JsonTypeInfo<T>.

As part of the work to make ASP.NET Core AOT-friendly, we have a need of those methods available. As an example, RDF needs to write the JSON response based on the runtime type and cannot create a typed JsonTypeInfo<T>.

aspnetcore/src/Http/Http.Extensions/src/RequestDelegateFactory.cs

Line 2261 in 63d2fb0

return HttpResponseJsonExtensions.WriteAsJsonAsync(response, value, value is null ? typeof(object) : value.GetType(), options, default);

Same for the uController source generator rely on the HttpResponse extensions to write a JSON content and might not be able to have a generic JsonTypeInfo.

https://github.com/davidfowl/uController/blob/86fe16e634bdc34e641c3d983a3f26bba80ccebe/GeneratedOutput/RouteBuilderExtensions.g.cs#L504

Proposed API

namespace Microsoft.AspNetCore.Http;

public static class HttpResponseJsonExtensions
{
+        public static Task WriteAsJsonAsync(
+                          this HttpResponse response, 
+                          object? value, 
+                          JsonTypeInfo jsonTypeInfo, 
+                          string? contentType = default, 
+                          CancellationToken cancellationToken = default);
}

namespace Microsoft.AspNetCore.Http;

public static class HttpRequestJsonExtensions
{
+        public static ValueTask<object?> ReadFromJsonAsync(
+                          this HttpRequest request,
+                          JsonTypeInfo jsonTypeInfo, 
+                          CancellationToken cancellationToken = default);
}

Usage Examples

ValueTask<object?>  ReadBody(HttpContext context, Type bodyType,  JsonSerializerOptions  jsonSerializerOptions)
{
     var bodyJsonTypeInfo = jsonSerializerOptions.GetTypeInfo(bodyType);
     return httpContext.Request.ReadFromJsonAsync(bodyJsonTypeInfo);
}

Task WriteResponse(HttpContext context, object? value, JsonSerializerOptions  jsonSerializerOptions)
{
     var runtimeType = value is null ? typeof(object) : value.GetType();
     var runtimeTypeInfo = jsonSerializerOptions.GetTypeInfo(runtimeType);
     return httpContext.Response.WriteAsJsonAsync(value, runtimeTypeInfo );
}

Alternative Designs

No response

Risks

No response

cc @eiriktsarpalis

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.
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• Someone is assigned to "champion" this change in the meeting, and they understand the impact and design of the change.

Thanks for contacting us.

We're moving this issue to the .NET 8 Planning milestone for future evaluation / consideration. We would like to keep this around to collect more feedback, which can help us with prioritizing this work. We will re-evaluate this issue, during our next planning meeting(s).
If we later determine, that the issue has no community involvement, or it's very rare and low-impact issue, we will close it - so that the team can focus on more important and high impact issues.
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[halter73]

API Review Notes:

1. This matches the pattern used by JsonSerializer.DeserializeAsync/SerializeAsync
2. We're curious how JsonSerializer handles null, but we figure it just treats the type as object.

API Approved as proposed!

[eiriktsarpalis]

We're curious how JsonSerializer handles null, but we figure it just treats the type as object

It throws, which is consistent with the generic overloads and how null arguments are treated in non-nullable parameter types. Generally speaking, a source generated context might not include metadata for object serialization.