阿波罗联盟实体参考工作不正常

Question

I've been wrestling with Apollo entities and their references for awhile now. I've followed this article to implement a relationship between articles (articles service) and their author (person service). The relevant code is as follows:

// Article service type definitions
export const typeDefs = gql`
  type Article @key(fields: "_id") @key(fields: "slug") {
    _id: ID!
    author: Person!
    category: String
    content: String
    media: String
    published: Boolean
    slug: String!
    subtitle: String
    title: String!
  }

...
`;

// Article service resolvers
...
Article: {
  author: <IArticleAuthor> ((article) => {
    return { __typename: 'Person', _id: article.author };
  }),
},
...

// Person service resolvers
...
__resolveReference: (reference: { _id: string }) => {
  return Person.findOne({ _id: { $eq: reference._id }});
},
...

The problem that occurs is that I only get the object that is returned in the article service resolvers page { __typename: 'Person', _id: article.author }; when I actually make a request. I was expecting that the __resolverReference function would be called once I made a request to fetch articles but it does not. Is there something that I'm missing to get this to work properly?

Answer 1

It ended up being a problem in the Person service. I had the __resolveReference method attached to the resolver object at the top-level instead of within a Person property.

export const resolvers = {
  __resolveReference: (reference) => Person.findOne({ _id: { $eq: reference.id } });
}

versus

export const resolvers = {
  Person: {
    __resolveReference: (reference) => Person.findOne({ _id: { $eq: reference.id } });
  }
}