extend schema @link(url: "https://specs.apollo.dev/federation/v2.3")

enum Genre {
  FICTION
  NONFICTION
  SCIFI
  FANTASY
  MYSTERY
  BIOGRAPHY
}

type Book {
  id: ID!
  title: String!
  genre: Genre
  author: Author
  publisher: Publisher
}

type Author @federation__key(fields: "id") {
  id: ID!
  name: String! @federation__shareable
  age: Int
  books: [Book]
}

type Publisher {
  id: ID!
  name: String!
  location: String
  books: [Book]
}