OpenAPI doesn't support stream parameters

[rmannibucau]

Is there an existing issue for this?

• I have searched the existing issues

Describe the bug

Microsoft.AspNetCore.OpenApi.OpenApiSchemaStore prepopulate the Stream schema (note that it doesn't use the latest openapi representation but that would be an enhancement) but the key uses parameterinfo (set to null by default) so the getoradd in the store fails cause when using [FromBody] Stream body there is a parameter info.

Note that setting Stream as metadata to avoid to have a parameter fails in Microsoft.AspNetCore.OpenApi.OpenApiSchemaService.GetOrCreateSchemaAsync cause there is an api description so it still tries to lookup a JsonTypeInfo.

TIP: using this code can workaround the issue in an ugly manner:

[JsonSourceGenerationOptions]
[JsonSerializable(typeof(Stream))] // make GetOrCreateSchemaAsync happy (ApplyParameterInfo)
public partial class OpenApiWorkaroundForStream : JsonSerializerContext;

builder.Services.ConfigureHttpJsonOptions(o => o
            .SerializerOptions
            .TypeInfoResolverChain
            .Add(OpenApiWorkaroundForStream.Default));

        app
            .MapPost(....)
            .WithMetadata(new AcceptsMetadata(["application/octect-stream"], typeof(Stream))); // no param so hardcoded schema is used

Expected Behavior

The Stream schema is looked up as expected

Steps To Reproduce

use an minimal api endpoint with request body in parameters

Exceptions (if any)

No response

.NET Version

9

Anything else?

No response