Custom directive on object

[dan-f]

Hi,

I'm having trouble implementing a directive via SchemaDirectiveWiring for object types. E.g.:

directive @foo on OBJECT

type Query {
  bar: Bar!
}

type Bar @foo {
  id: ID!
}

class FooDirective : SchemaDirectiveWiring {
  override fun onObject(
    environment: SchemaDirectiveWiringEnvironment<GraphQLObjectType>
  ): GraphQLObjectType {
    // what actually goes in here?
  }

I've tried a number of implementations, including what's indicated over here: https://github.com/graphql-java/graphql-java/blob/master/src/test/groovy/graphql/schema/idl/SchemaGeneratorDirectiveHelperTest.groovy#L471

For some reason, my wrapping (outer) data fetcher is just not getting invoked. I don't know if it's significant, but I've noticed that when calling GraphQLCodeRegistry.dataFetcher, it's unclear what to actually pass as the parent type vs. field. I.e. I'd have expected some internal representation of Query to be the parent type with bar as the field, but I can see in the debugger that environment.element and environment.fieldsContainer both point to the same exact object -- the GraphQLObjectType instance representing the Bar, with no obvious reference to the parent on any of the environment APIs.

The other thing that seems odd to me is the fact that the code sample from the test suite is wrapping the child fields of the object type, rather than that object type itself as a child of it's own parent. I'm hoping there's a straightforward answer to this!