Controller action enum parameter binding as string - json

Question

I have a Web API controller action
[Route("{type}")]
public IEnumerable<Content> Get(ContentType type)
{
...
}
where ContentType is enumeration and type is being provided as a string and not as an integer.
As I've checked the JsonConverterAttribute class which seems it should be possible to put it beside a method parameter
[AttributeUsage(AttributeTargets.Class |
AttributeTargets.Struct |
AttributeTargets.Enum |
AttributeTargets.Property |
AttributeTargets.Field |
AttributeTargets.Interface |
AttributeTargets.Parameter, // <= HERE!
AllowMultiple = false)]
public class JsonConverterAttribute : Attribute
...
but this doesn't seem to work:
[Route("{type}")]
public IEnumerable<Content> Get([JsonConverter(typeof(StringEnumConverter))] ContentType type)
{
...
}
I'm getting an error:
The parameters dictionary contains a null entry for parameter 'type' of non-nullable type '....ContentType' for method '...' in '...'. An optional parameter must be a reference type, a nullable type, or be declared as an optional parameter.
I also don't want to put this converter inside my global configuration as I want my enums to serialize as integers. There are just a few places where I need to deserialize them from strings.
The possible alternative is to pass in a string and parse it manually using Enum.Parse() method but I'd like to avoid it if possible.