I'm thinking about having my query response types ...

# graphql-kotlin

[rocketraman]

I'm thinking about having my query response types use functions to load data as needed. For example:

data class SomeSuccessType(
  val foo: Foo,
  @property:GraphQLIgnore val bar: suspend () -> Bar?,
) {
  suspend fun bar() = bar.invoke()
}

With this approach my data model does not need to know anything about the various services and such being used to look up this data (like in the example given at https://opensource.expediagroup.com/graphql-kotlin/docs/server/data-loaders, the model class needs a reference to friendService and userService, which I think is messy to say the least). Instead, the loader logic here exists outside the data class/model and is simply injected via a function.

However, when trying this approach, I am confronted with:

Exception in thread "main" kotlin.reflect.jvm.internal.KotlinReflectionInternalError: Cannot calculate JVM erasure for type: suspend () -> Bar?
  at kotlin.reflect.jvm.KTypesJvm.getJvmErasure(KTypesJvm.kt:36)
  at com.expediagroup.graphql.generator.internal.extensions.KTypeExtensionsKt.getKClass(kTypeExtensions.kt:38)
  at com.expediagroup.graphql.generator.internal.extensions.KTypeExtensionsKt.getQualifiedName(kTypeExtensions.kt:73)
  ...

Any work-around for this? If not, what other techniques are people using to do data loading without all the messiness?

[rocketraman]

Defining isValidProperty in the generator hooks to exclude that proeprty works, but I would have thought any @GraphQLIgnore annotated property would already have been excluded by default?

[rocketraman]

Making it private works. Also manually looking for the GraphQLIgnore annotation in isValidProperty and excluding it works, so it certainly seems like a bug.

[Dariusz Kuc]

if making it private works then it sounds like a bug

[rocketraman]

Thanks for the confirmation. I've created https://github.com/ExpediaGroup/graphql-kotlin/issues/1364.