Is there something like a type resolver init that can run before field resolvers?

Server
1

I’m looking for some sort of way to initialize the ‘parent’ values which the fields later use in order to implement lazy loading. So I only load the whole object from DB only if needed.

// Schema
type Book {...}

UpdateBookReturn {
  updatedBookId: ID!
  updatedBook: Book
}

mutation {
  updateBook(bookId: ID!, title: String, authorId: ID): UpdateBookReturn
}

// Resolver
Mutation = {
...
  updateBook: (_parent, params) => {
    void doBookUpdate(params)
    return {
      updatedBookId: params.bookId,
      updatedBook: { __type: 'Book', id: parms.bookId }
    }
  },
}

Book {
   // I want this to run first.
   $someInit: (parent) => {
     parent.rootValue = getBook(parent.id)
   }
  author: (parent) => parent.author
  title: (parent) => parent.title
  ...
}

So if someone selects updatedBookId it can return that right a way without the extra hit to the DB, but if they do select updatedBook, it can load the book.

Note: This is over simplified example. The reason I’m looking for a init is because there are multiple mutations that will be using this. So I don’t want to use a async function inside the mutation return, which I’ll need to repeat.

Thanks.