如何使用GraphQL.NET验证空请求？

Question

可能会向使用GraphQL.NET和asp.net core 2实现的Graphql服务器发送空请求。

我尝试使用asp.net core 2动作过滤器来实现它，但似乎无法正常工作。

// Startup.cs
public void ConfigureServices(IServiceCollection services)
{
    //services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
    services.AddMvc(options =>
    {
        options.Filters.Add(typeof (CheckModelForNullAttribute));
        options.Filters.Add(typeof (ValidateModelStateAttribute));
    }

    ).SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
}
// GraphQLController.cs

[Route("[controller]")]
public class GraphQLController : Controller
{
    private readonly IDocumentExecuter _documentExecuter;
    private readonly ISchema _schema;
    public GraphQLController(ISchema schema, IDocumentExecuter documentExecuter)
    {
        _schema = schema;
        _documentExecuter = documentExecuter;
    }

    [HttpPost]
    public async Task<IActionResult> Post([FromBody] GraphQLQuery query)
    {
        if (query == null)
        {
            throw new ArgumentNullException(nameof(query));
        }

        var inputs = query.Variables.ToInputs();
        var executionOptions = new ExecutionOptions{Schema = _schema, Query = query.Query, Inputs = inputs, UserContext = Request.Headers, //UserContext = new GraphQLUserContext { Headers = Request.Headers }
 };
        var result = await _documentExecuter.ExecuteAsync(executionOptions).ConfigureAwait(false);
        if (result.Errors?.Count > 0)
        {
            return BadRequest(result);
        }

        return Ok(result);
    }
}

// CheckModelForNullAttribute.cs

public class CheckModelForNullAttribute : ActionFilterAttribute
{
    public override void OnActionExecuting(ActionExecutingContext context)
    {
        if (context.ActionArguments.Any(c => c.Value == null))
        {
            context.Result = new BadRequestObjectResult(context.ModelState);
        }
    }
}

// ValidateModelStateAttribute.cs

public class ValidateModelStateAttribute : ActionFilterAttribute
{
    public override void OnActionExecuting(ActionExecutingContext context)
    {
        if (!context.ModelState.IsValid)
        {
            context.Result = new BadRequestObjectResult(context.ModelState);
        }
    }
}

有人可以帮助我解决此问题吗？