Add Api Parameter Description to Api Description to represent the request body

[rafikiassumani-msft]

Background and Motivation

1. Minimal APIs should be able to add their own ConsumesRequestTypeAttribute to their endpoint metadata, either by decorating the method/lambda with the ConsumesRequestTypeAttribute, or via new Accepts(string contentType) or Accepts<TRequest>(string contentType) methods on MinimalActionEndpointConventionBuilder. This should override any consumes metadata that was added via the 1st proposal (i.e. the 1st proposal is likely implemented as fallback logic in the endpoint builder).

1. ApiExplorer should be updated to add a ApiParameterDescription to the ApiDescription to represent the incoming request body based on the details in the endpoint's IApiRequestMetadataProvider metadata if present.
   • Note Swashbuckle expects this in order to generate the incoming request body schema

Proposed API

 namespace Microsoft.AspNetCore.Http
{
    public static class OpenApiEndpointConventionBuilderExtensions
    {
+        public static DelegateEndpointConventionBuilder Accepts<TRequest>(this DelegateEndpointConventionBuilder 
+        builder,  string contentType, params string[] additionalContentTypes) where TRequest : notnull
  }
}

Usage Examples

app.MapPost("/create-todo", (Todo todo) => $"{todo.Name}").Accepts<Todo>("application/xml");

Risks

very low.

[rafikiassumani-msft]

The API proposal is not needed anymore as we decided to stay consistent with mvc and use ConsumesAttribute. We overloaded the constructor to allow a type.

Usage example:

 [Consumes(typeof(SampleDataDTO), "application/xml", "application/json")]