How to access field level Graphql directive with graphql-spqr

Question

Given a graphql Query

query @my (arg:1) {
  foo @my (arg:2) {
    bar @my (arg:3)
    foobar @my (arg:4)
  }
}

And graphql server implementation using graphql-spqr

@GraphQLType(name="foo")
public class Foo{
   @GraphQLQuery(name="bar")
   public String bar;
   @GraphQLQuery(name="foobar")
   public String foobar;
}

@GraphQLDirective(name="my", locations = {QUERY, FIELD} )
public class MyGraphqlDirective{
  @GraphqlInputField("arg")
  public int arg;
}

public class GraphqlService{
   @GraphQLQuery(name = "foo")
   public Foo foo(@Nullable @GraphQLDirective(name="my") MyGraphqlDirective my){
      Foo foo=new Foo();
      if(my!=null){
         foo.bar = String.valueOf(my.arg);
         foo.foobar = String.valueOf(my.arg);
      }
      return foo;
   }
}

I have access to (arg:2) on the query foo, if it is exists, and fallback to (arg:1) if that was absent.

However, I have problem if I would like to read that on field foo and foobar.

I'd want to, make it not readable, abusing @GraphqlContext for every single field. Is there any easier way to archive some simple logic (e.g. uppercase, locale, rounding, number format) on field level.

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Also tried dataFetchingEnvironment.getSelectionSet().get().getSubField("edge/node/foo/bar").getSingleField().getDirective() which doesn't take the Directive from parent

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