GraphQL Issue using Interfaces on Relationship Types with Properties

Drivers & Stacks GraphQL & GRANDstack
1

Hi. I have been successfully defining schemas that use relationships with interfaces but I just tried to do this with a relationship type that has properties and then the schema won't validate.

Example:

Using the schema from the docs with: Person, User, and Actor, etc I want to include the friends relationship as part of the Person Interface but attach a since property to the friends relationship. My approach was this:

interface Person {
  id: ID!
  name: String
  friends: [Friend]
}

type Friend @relation (name: "FRIEND_OF") {
  from: Person
  to: Person
  since: Date
}

type User implements Person {
  id: ID!
  name: String
  friends: [Friend]

  screenName: String
  reviews: [Review] @relation(name: "WROTE", direction: OUT)
}

type Actor implements Person {
  id: ID!
  name: String
  friends: [Friend]
  movies: [Movie] @relation(name: "ACTED_IN", direction: OUT)
}

type Movie {
  movieId: ID!
  title: String
}

type Review {
  rating: Int
  created: DateTime
  movie: Movie @relation(name: "REVIEWS", direction: OUT)
}

When I run this the schema validator complains that the type User is implementing the Friend relationship but that Friend is defined as having the to and from types as Person. I assumed the validator would resolve the use of types implementing interfaces for these fields. Is there another way to handle this or am I missing something?

Thanks,
Nick

2

You may have to define the relationship as a field on the interface like:

interface Person {
  id: ID!
  name: String
  friends: [Friend] @relation(name: "FRIEND_OF", direction: OUT/IN)
}

Just like you have for your Review relationship. Not sure if that will work but it might.