public override void OnActionExecuting(ActionExecutingContext context)
{
var model = context.ActionArguments.FirstOrDefault(a => a.Key == "model");
if(model.Key == "model" && model.Value == null)
{
context.ModelState.AddModelError(string.Empty, "Body is empty.");
}
if(!context.ModelState.IsValid)
{
context.Result = new BadRequestObjectResult(new ErrorResponseModel(context.ModelState));
}
}