Incorrect nullability on IApiRequestFormatMetadataProvider.GetSupportedContentTypes #62405
Description
Is there an existing issue for this?
- I have searched the existing issues
Describe the bug
The contentType parameter in Microsoft.AspNetCore.Mvc.ApiExplorer.IApiRequestFormatMetadataProvider.GetSupportedContentTypes is annotated as non-nullable. However, null is explicitly being passed from DefaultApiDescriptionProvider.GetSupportedFormats here.
This causes crashes in our custom implementation of IApiRequestFormatMetadataProvider.GetSupportedContentTypes, which doesn't expect a null content type.
Please correct the nullability of this parameter, and potentially related places where applicable.
Expected Behavior
The contentType parameter to be annotated as nullable.
Steps To Reproduce
Register a custom implementation of IInputFormatter with the following implementation:
internal sealed class ExampleApiRequestFormatMetadataProvider : IInputFormatter, IApiRequestFormatMetadataProvider
{
public bool CanRead(InputFormatterContext context)
{
return false;
}
public Task<InputFormatterResult> ReadAsync(InputFormatterContext context)
{
throw new UnreachableException();
}
public IReadOnlyList<string> GetSupportedContentTypes(string contentType, Type objectType)
{
ArgumentNullException.ThrowIfNull(contentType); // <--- crash here
ArgumentNullException.ThrowIfNull(objectType);
return [];
}
}Load the OpenAPI document using Swashbuckle, for the following API controller:
[Route("[controller]")]
public sealed class ExampleController : ControllerBase
{
[HttpPut]
public IActionResult Put([FromBody] string name)
{
string result = $"Hi, {name}";
return Ok(result);
}
}Exceptions (if any)
No response
.NET Version
.NET 8 and 9 on Windows / Visual Studio
Anything else?
