Resolving Dynamic Fields for Implementing Types

[3axap4eHko]

Problem Description:
I have an issue with resolving the url field for a Post object. The Post type implements the Linkable interface, and I expect the url field to be resolved by the Linkable resolver. However, I'm encountering an issue where type Resolvers expects the url field to be part of the PostDocument type, even though it's supposed to be resolved dynamically.

Code:

# Schema Definition
interface Linkable {
  url: URL!
  slug: String!
}

type Post implements Linkable {
  url: URL!
  slug: String!
  title: String!
  content: String!
}

type Query {
  post(id: String!): Post
}

export interface PostDocument {
  slug: string;
  title: string;
  content: string;
}

export const resolvers: Resolvers = {
  Linkable: {
    url({ slug ) {
      return `https://example.com/post/${slug}`;
    }
  },
  Query: {
    post(_, { id }, { db }) {
      return db.collection('posts').findOne<PostDocument>({ slug: id });
    }
  }
};