Error Abstract type Search must resolve to an Object type at runtime for field Query.search

helo friends,

Someone who can help me solve a problem in Apollo Graphql. I have implemented a search query that receives a parameter that is the title to search, the problem I have is that it shows me the following error:

"message": "Abstract type Search must resolve to an Object type at runtime for field Query.search with value { id: \"avatar\", title: \"Avatar\", poster: \"https://pedropolis.tv/wp-content/uploads/2009/12/Avatar-150x150.jpg\", sinopsis: \"Jake Sully, un ex-marine confinado a una silla de ruedas, es reclutado para viajar al planeta Pandora, donde un consorcio corporativo está extrayendo un mineral que será clave en la solución de ...\", type: \"pelicula\", extra: [[Object]] }, received \"undefined\". Either the Search type should provide a \"resolveType\" function or each possible type should provide an \"isTypeOf\" function.",

The return type of the search is a union of the type Series | Movies

❤️ Any help will be more than received, I’ve been trying to solve the problem for a couple of weeks.

Query

const resolvers = require('./resolvers.js');
const {gql} = require('apollo-server');

const typeDefs = gql `
  extend type Query{
    search(query: String!): [Search!]!
  }

  union Search = Series | Movies

  type Series{
    id: String!
    title: String!
    sinopsis: String!
    poster: String!
    rating: String!
    year: String!
    extra: [SerieExtra!]!
  }

  type Movies{
    id: String!
    title: String!
    sinopsis: String!
    poster: String!
    rating: String!
    quality: String!
    year: String!
    extra: [MovieExtra!]!
  }

  type Episodes{
    id: String!
    title: String!
    episode_name: String!
    poster: String!
    date: String!
    quality: String!
    sinopsis: String!
  }

  type VideoIframe{
    iframe: Iframe
  }

  type Iframe{
    option: Int 
    video_iframe: String
  }

  type SerieExtra {
    channel: String!
    first_air_date: String!
    last_air_date: String!
    total_seasons: String!
    total_episodes: String
    season_list: [SeasonList!] !
    cast_members: CastMembers!
    similar_series: [SimilarSeries!] !
  }

  type MovieExtra {
    air_date: String!
    country: String!
    runtime: String!
    rated: String!
    cast_members: CastMembers!
    similar_movies: [SimilarMovies!] !
  }

// The information of the type SeasonList, CastMembers, SimilarSeries, SimilarMovies
// It was omitted since it would be a lot of information in the template .. for this discussion.
`;

module.exports = {
  typeDefs,
  resolvers
}

resolvers

const resolvers = { 
 Search:{
    __resolveType(obj , context , info){
      // .....
      return null;
    }
  },
  Query:{ 
    search: async(_source , {query} , { dataSources}) =>{
    return dataSources.API.search(query)
        .then(doc => {
          console.log(doc.content) // It correctly shows me the query data.
          return doc.content;
        });
     },
  }
};

Playground

query{
    search(query: "avatar"){
      ... on Series{
        id
    }
      ... on Movies{
        id
    }
  }
}

Error

{
  "errors": [
    {
      "message": "Abstract type Search must resolve to an Object type at runtime for field Query.search with value { id: \"avatar\", title: \"Avatar\", poster: \"https://pedropolis.tv/wp-content/uploads/2009/12/Avatar-150x150.jpg\", sinopsis: \"Jake Sully, un ex-marine confinado a una silla de ruedas, es reclutado para viajar al planeta Pandora, donde un consorcio corporativo está extrayendo un mineral que será clave en la solución de ...\", type: \"pelicula\", extra: [[Object]] }, received \"undefined\". Either the Search type should provide a \"resolveType\" function or each possible type should provide an \"isTypeOf\" function.",
      "locations": [
        {
          "line": 2,
          "column": 3
        }
      ],
      "path": [
        "search",
        0
      ],
      "extensions": {
        "code": "INTERNAL_SERVER_ERROR",
        "exception": {
          "message": "Abstract type Search must resolve to an Object type at runtime for field Query.search with value { id: \"avatar\", title: \"Avatar\", poster: \"https://pedropolis.tv/wp-content/uploads/2009/12/Avatar-150x150.jpg\", sinopsis: \"Jake Sully, un ex-marine confinado a una silla de ruedas, es reclutado para viajar al planeta Pandora, donde un consorcio corporativo está extrayendo un mineral que será clave en la solución de ...\", type: \"pelicula\", extra: [[Object]] }, received \"undefined\". Either the Search type should provide a \"resolveType\" function or each possible type should provide an \"isTypeOf\" function.",
          "locations": [
            {
              "line": 2,
              "column": 3
            }
          ],
          "stacktrace": [
            "GraphQLError: Abstract type Search must resolve to an Object type at runtime for field Query.search with value { id: \"avatar\", title: \"Avatar\", poster: \"https://pedropolis.tv/wp-content/uploads/2009/12/Avatar-150x150.jpg\", sinopsis: \"Jake Sully, un ex-marine confinado a una silla de ruedas, es reclutado para viajar al planeta Pandora, donde un consorcio corporativo está extrayendo un mineral que será clave en la solución de ...\", type: \"pelicula\", extra: [[Object]] }, received \"undefined\". Either the Search type should provide a \"resolveType\" function or each possible type should provide an \"isTypeOf\" function.",
            "    at ensureValidRuntimeType (C:\\Users\\c\\Desktop\\cinemanight-graphql\\node_modules\\graphql\\execution\\execute.js:667:11)",
            "    at completeAbstractValue (C:\\Users\\c\\Desktop\\cinemanight-graphql\\node_modules\\graphql\\execution\\execute.js:660:42)",
            "    at completeValue (C:\\Users\\c\\Desktop\\cinemanight-graphql\\node_modules\\graphql\\execution\\execute.js:585:12)",
            "    at completeValue (C:\\Users\\c\\Desktop\\cinemanight-graphql\\node_modules\\graphql\\execution\\execute.js:557:21)",
            "    at completeValueCatchingError (C:\\Users\\c\\Desktop\\cinemanight-graphql\\node_modules\\graphql\\execution\\execute.js:495:19)",
            "    at C:\\Users\\c\\Desktop\\cinemanight-graphql\\node_modules\\graphql\\execution\\execute.js:618:25",
            "    at Array.forEach (<anonymous>)",
            "    at forEach (C:\\Users\\c\\Desktop\\cinemanight-graphql\\node_modules\\iterall\\index.js:83:25)",
            "    at completeListValue (C:\\Users\\c\\Desktop\\cinemanight-graphql\\node_modules\\graphql\\execution\\execute.js:614:24)",
            "    at completeValue (C:\\Users\\c\\Desktop\\cinemanight-graphql\\node_modules\\graphql\\execution\\execute.js:573:12)"
          ]
        }
      }
    }
  ],
  "data": null
}

[usama-asfar]

When using unions, you will have to return a __typename so apollo-server knows which type the result has and which resolver map must be used for resolving further field values of the resolved type.

search query must be something like below

Query: {
  search: async (_source, { query }, { dataSources }) => {
    const data = dataSources.API.search(query)

    if (data.name === 'Series') return {
      __typename: 'Series',
      ...data
    }

    if (data.name === 'Movies') {
      __typename: 'Movies',
      ...data
    }
  }
}

[MarshHawk]

Simplest (fewest extra lines of code) solution follows:

const resolvers = {
  Search:{
    __resolveType(parent) {
    return parent.constructor.name
  }
},

  SMovies:{
    ...
  },

  SSeries:{
    ...
  },

  MovieExtra:{
    ...
  },

  SerieExtra:{
    ...
  },


  Query: {
    search: async(_source , {query} , { dataSources}) =>{
      return dataSources.API.search(query)
        .then(doc => {
          return doc.content;
        })
    },
  }
};

module.exports = resolvers;

No Need for __typename: or _isTypeOf: