Javascript Graphql超高返回数组

我正在使用阿波罗服务器创建一个REST查询，该查询返回如下数据：

{
  "symbol": "AAPL",
  "companyName": "Apple Inc.",
  "exchange": "Nasdaq Global Select",
  "industry": "Computer Hardware",
  "website": "http://www.apple.com",
  "description": "Apple Inc is an American multinational technology company. It designs, manufactures, and markets mobile communication and media devices, personal computers, and portable digital music players.",
  "CEO": "Timothy D. Cook",
  "issueType": "cs",
  "sector": "Technology",
  "tags": [
      "Technology",
      "Consumer Electronics",
      "Computer Hardware"
  ]
}

const typeDefs = gql`
    type Query{
        stock(symbol:String): Stock
    }

    type Stock {
        companyName: String
        exchange: String
        industry: String
        tags: String!
    }
`;
const resolvers = {
    Query:{
        stock: async(root, {symbol}, {dataSources}) =>{
            return dataSources.myApi.getSomeData(symbol)
        }
    }
};

class MyApiextends RESTDataSource{
    constructor(){
        super();
        this.baseURL = 'https://api.iextrading.com/1.0';
    }

    async getSomeData(symbol){
        return this.get(`/stock/${symbol}/company`)
    }
}

module.exports = MyApi

tags: [String]

我正在使用。我的

typeDefs

和

resolvers

如下所示：

{
  "symbol": "AAPL",
  "companyName": "Apple Inc.",
  "exchange": "Nasdaq Global Select",
  "industry": "Computer Hardware",
  "website": "http://www.apple.com",
  "description": "Apple Inc is an American multinational technology company. It designs, manufactures, and markets mobile communication and media devices, personal computers, and portable digital music players.",
  "CEO": "Timothy D. Cook",
  "issueType": "cs",
  "sector": "Technology",
  "tags": [
      "Technology",
      "Consumer Electronics",
      "Computer Hardware"
  ]
}

const typeDefs = gql`
    type Query{
        stock(symbol:String): Stock
    }

    type Stock {
        companyName: String
        exchange: String
        industry: String
        tags: String!
    }
`;
const resolvers = {
    Query:{
        stock: async(root, {symbol}, {dataSources}) =>{
            return dataSources.myApi.getSomeData(symbol)
        }
    }
};

class MyApiextends RESTDataSource{
    constructor(){
        super();
        this.baseURL = 'https://api.iextrading.com/1.0';
    }

    async getSomeData(symbol){
        return this.get(`/stock/${symbol}/company`)
    }
}

module.exports = MyApi

tags: [String]

数据源文件如下所示：

{
  "symbol": "AAPL",
  "companyName": "Apple Inc.",
  "exchange": "Nasdaq Global Select",
  "industry": "Computer Hardware",
  "website": "http://www.apple.com",
  "description": "Apple Inc is an American multinational technology company. It designs, manufactures, and markets mobile communication and media devices, personal computers, and portable digital music players.",
  "CEO": "Timothy D. Cook",
  "issueType": "cs",
  "sector": "Technology",
  "tags": [
      "Technology",
      "Consumer Electronics",
      "Computer Hardware"
  ]
}

const typeDefs = gql`
    type Query{
        stock(symbol:String): Stock
    }

    type Stock {
        companyName: String
        exchange: String
        industry: String
        tags: String!
    }
`;
const resolvers = {
    Query:{
        stock: async(root, {symbol}, {dataSources}) =>{
            return dataSources.myApi.getSomeData(symbol)
        }
    }
};

class MyApiextends RESTDataSource{
    constructor(){
        super();
        this.baseURL = 'https://api.iextrading.com/1.0';
    }

    async getSomeData(symbol){
        return this.get(`/stock/${symbol}/company`)
    }
}

module.exports = MyApi

tags: [String]

我可以运行查询并返回数据，但它不是在数组中格式化，并且在我运行以下查询时引发错误：

query{
  stock(symbol:"aapl"){
    tags
  }
}

错误：

{
  "data": {
    "stock": null
  },
  "errors": [
    {
      "message": "String cannot represent value: [\"Technology\", \"Consumer Electronics\", \"Computer Hardware\"]",
      "locations": [
        {
          "line": 3,
          "column": 5
        }
      ],
      "path": [
        "stock",
        "tags"
      ],
      "extensions": {
        "code": "INTERNAL_SERVER_ERROR",
        "exception": {
          "stacktrace": [
            "TypeError: String cannot represent value: [\"Technology\", \"Consumer Electronics\", \"Computer Hardware\"]",

我期望的数据（技术、消费电子产品和计算机硬件）是正确的，但不会以数组形式返回。我尝试为标记创建一个新的

类型

，并使用tag属性设置它，但该值只返回

null

---

我对graphql非常陌生，因此任何反馈都非常感谢

在

股票

的类型定义中，您将

标签

字段的类型定义为

字符串：

tags: String!

这告诉GraphQL期望一个不为null的字符串值。但是，REST端点返回的实际数据不是字符串，而是字符串数组。因此，您的定义应至少如下所示：

{
  "symbol": "AAPL",
  "companyName": "Apple Inc.",
  "exchange": "Nasdaq Global Select",
  "industry": "Computer Hardware",
  "website": "http://www.apple.com",
  "description": "Apple Inc is an American multinational technology company. It designs, manufactures, and markets mobile communication and media devices, personal computers, and portable digital music players.",
  "CEO": "Timothy D. Cook",
  "issueType": "cs",
  "sector": "Technology",
  "tags": [
      "Technology",
      "Consumer Electronics",
      "Computer Hardware"
  ]
}

const typeDefs = gql`
    type Query{
        stock(symbol:String): Stock
    }

    type Stock {
        companyName: String
        exchange: String
        industry: String
        tags: String!
    }
`;
const resolvers = {
    Query:{
        stock: async(root, {symbol}, {dataSources}) =>{
            return dataSources.myApi.getSomeData(symbol)
        }
    }
};

class MyApiextends RESTDataSource{
    constructor(){
        super();
        this.baseURL = 'https://api.iextrading.com/1.0';
    }

    async getSomeData(symbol){
        return this.get(`/stock/${symbol}/company`)
    }
}

module.exports = MyApi

tags: [String]

如果希望GraphQL在标记值为null时抛出，请在末尾添加感叹号以使其不可为null：

tags: [String]!

如果希望GraphQL在数组中的任何值为空时抛出，请在括号内添加感叹号。您还可以将这两者结合起来：

tags: [String!]!

欢迎来到SO！查看您的数据源代码也会很有帮助。你能更新你的问题，把它也包括进去吗？好的，我把它添加到问题中了