graphql中未定义类型的输出错误

Posted 2023-03-11

【中文标题】graphql中未定义类型的输出错误

【英文标题】：undefined type of output error in graphql

【发布时间】：2019-04-25 09:53:34

【问题描述】：

我用 mongodb 在 graphql 服务器和 nodejs 中编写了一个简单的代码。我有一个包含 2 个集合的数据库。明星和电影。当我运行此查询以显示所有电影时，我的 GraphQL NodeJS 服务器出现以下错误： “MovieType.year 的类型必须是 Output Type 但得到：未定义。”

这是我的架构：

    const 
    GraphQLSchema,
    GraphQLObjectType,
    GraphQLString,
    GraphQLInt,
    GraphQLNonNull,
    GraphQLList
 = require("graphql");
const Movie, User = require('/home/fateme/imdb_final/db')


const starType = new GraphQLObjectType(
    name: "UserType",
    fields: 
      name: 
        type: GraphQLString,
        async resolve(objId) 
            const starFind = await User.findOne( _id: objId._id)
            return starFind.name
        
      ,
      imdbId: 
        type: GraphQLString,
        async resolve(objId) 
            const starFind = await User.findOne( _id: objId._id) 
            return starFind.imdbId
        
      
    
  );

const movieType = new GraphQLObjectType(
    name: "MovieType",
    fields: 
      title: 
        type: GraphQLString,
        async resolve(objId) 
            const movieFind = await Movie.findOne( _id: objId._id)
            return movieFind.title
        
      ,
      year: 
        type: GraphQLInt,
        async resolve(objId) 
            const movieFind = await Movie.findOne( _id: objId._id)
            return movieFind.year
        
      ,
      rate: 
        type: GraphQLInt,
        async resolve(objId) 
            const movieFind = await Movie.findOne( _id: objId._id)
            return movieFind.rating
        
      ,
      year: 
        rate: GraphQLInt,
        async resolve(objId) 
            const movieFind = await Movie.findOne( _id: objId._id)
            return movieFind.year
        
      ,
      director: 
        type: GraphQLString,
        async resolve(objId) 
            const movieFind = await Movie.findOne( _id: objId._id)
            return movieFind.director
        
      ,
    
  );


  const queryType = new GraphQLObjectType(
    name: 'Query',
    fields: () => (

        users: 
            type: GraphQLList(starType),
            async resolve() 

              const allStar = await User.find()
              return  allStar
            
          ,

      movies: 
        type: GraphQLList(movieType),
        async resolve() 

            const allMovie = await Movie.find()
            console.log(allMovie)
            return  allMovie
           
        ,
    )
  );

  const schema = new GraphQLSchema(
    query: queryType
  );

  module.exports = schema;

【参考方案1】：

如错误所示，您尚未为 year 字段定义类型。相反，您不小心添加了 rate 字段：

year: 
    rate: GraphQLInt, // <-- here
    async resolve(objId) 
        const movieFind = await Movie.findOne( _id: objId._id)
        return movieFind.year
    
,

只需将 rate 更改为 type 即可：)