如何在GraphQL中插入（数组）字段列表进行变异查询

Question

最近我开始研究GraphQL，我能够在平面模式中插入数据，没有任何问题，但是当涉及到数据数组时，我会遇到如下错误

 { "errors": [ {  "message": "Must be input type" } ]}

我正在用postman测试我的查询，我的变异查询是

mutation M { 

AddEvent
  (

    title: "Birthday event"   

    description:"Welcome to all" 

    media:[{url:"www.google.com", mediaType:"image" }]

    location:[{address:{state:"***", city:"****"}}]

   ) 

{title,description,media,location,created,_id}}

这是我的事件模式：

EventType = new GraphQLObjectType({
  name: 'Event',
  description: 'A Event',
  fields: () => ({
   _id: {
      type: GraphQLString,
      description: 'The id of the event.',
    },
     id: {
      type: GraphQLString,
      description: 'The id of the event.',
    },
    title: {
      type: GraphQLString,
      description: 'The title of the event.',
    },
     description: {
      type: GraphQLString,
      description: 'The description of the event.',
    },
    media:{
      type:new GraphQLList(mediaType),
      description:'List of media',   
    },
    location:{
      type:new GraphQLList(locationType),
      description:'List of location',   
    }  
  })
});

// Media Type

export var mediaType = new GraphQLObjectType({
  name: 'Media',
  description: 'A Media',
  fields: () => ({
   _id: {
      type: GraphQLString,
      description: 'The id of the event.',
    },
   url:{
      type: GraphQLString,
      description: 'The url of the event.',
    },
    mediaType:{
      type: GraphQLString,
      description: 'The mediaTypa of the event.',
    }
  })
});

 // Location Type

export var locationType = new GraphQLObjectType({
  name: 'Location',
  description: 'A location',
  fields: () => ({
  _id: {
      type: GraphQLString,
      description: 'The id of the event.',
    },
    address:{
      type: GraphQLString,
      description: 'The address.',
    },
    state:{
      type: GraphQLString,
      description: 'The state.',
    },
    city:{
      type: GraphQLString,
      description: 'The city.',
    },
    zip:{
      type: GraphQLString,
      description: 'The zip code.',
    },
    country:{
      type: GraphQLString,
      description: 'The country.',
    }
  })
});

猫鼬模式：

var EventSchema = new mongoose.Schema({
  title: {
        required: true,
        type: String,
        trim: true,
        match: /^([\w ,.!?]{1,100})$/
    },
    description: {
        required: false,
        type: String,
        trim: true,
        match: /^([\w ,.!?]{1,100})$/
    },
    media: [{
        url: {
            type: String,
            trim: true
        },
        mediaType: {
            type: String,
            trim: true
        }
    }],
    location: [{
            address: {
                type: String
            },
            city: {
                type: String
            },
            state: {
                type: String
            },
            zip: {
                type: String
            },
            country: {
                type: String
            }
    }]
})

突变类型：

 addEvent: {
        type: EventType,
        args: {

        _id: {
          type: GraphQLString,
          description: 'The id of the event.',
        },
        title: {
          type: GraphQLString,
          description: 'The title of the event.',
        },
        description: {
          type: GraphQLString,
          description: 'The description of the event.',
        },
        media:{
          type:new GraphQLList(mediaType),
          description:'List of media',   
        },
        location:{
          type:new GraphQLList(locationType),
          description:'List of media',   
        },
        created: {
          type: GraphQLInt,
          description: 'The created of the user.',       
        } 
         },
      resolve: (obj, {title,description,media,location,created,_id}) => {

        let toCreateEvent = {
          title,
          description,
          created:new Date(),
          start: new Date(),
          media,
          location,
          _id,
        };

         return mongo()
            .then(db => {
              return  new Promise(
                function(resolve,reject){
              let collection = db.collection('events');
                  collection.insert(toCreateEvent, (err, result) => {
                    db.close();

                    if (err) {
                      reject(err);
                      return;
                    }
                    resolve(result);
                  });
            })
          });
       }
     }

Answer 1

我遇到了同样的问题——我不知道如何在输入定义中指定对象数组。所以对于那些想看到“文本”模式解决方案的人来说：

type Book {
  title: String!
}

在您的输入类型中有一个书籍数组

input AuthorInput {
  name: String!
  age: Int!
}

您不能只添加书籍：[Book！] 在输入语句中，您需要故意创建包含所需字段的输入类型（如果愿意，请复制）：

input BookInput {
  title: String!
}

然后你可以：

input AuthorInput {
  name: String!
  age: Int!
  books: [BookInput!]
}

Answer 2

您的问题是，当您定义突变时，所有类型都必须是输入类型，因此您会得到错误必须是输入类型。所以在这里（从你的突变中）：

media:{
  type:new GraphQLList(mediaType),
  description:'List of media',   
},
location:{
  type:new GraphQLList(locationType),
  description:'List of media',   
},

graphqlist、mediaType和locationType必须是输入类型。

GraphQLList已经是一个输入类型（请参阅此处https://github.com/graphql/graphql-js/blob/master/src/type/definition.js#L74-L82查看被视为输入类型的GraphQL类型列表）。

但是，您的类型mediaType和locationType属于GraphQLObjectType类型，它不是输入类型，但如果您再次查看输入类型列表：https://github.com/graphql/graphql-js/blob/master/src/type/definition.js#L74-L82，您会发现GraphQLInputObjectType是一种对象输入类型，因此，您需要做的是将mediaType和locationType替换为它们的“输入”版本。

我建议创建mediaInputType和locationInputType，它们将具有与mediaType和locationType相同的字段结构，但创建时使用新的GraphQlinputObject类型（{…），而不是新的GraphQLObjectType（{…）。

我遇到了同样的问题，我就这样解决了，如果你有任何问题，请随意评论。