“User”类型的字段“me”必须具有一系列子字段

嗨，我正在努力学习GraphQL语言。我有下面的代码片段。

// Welcome to Launchpad!
// Log in to edit and save pads, run queries in GraphiQL on the right.
// Click "Download" above to get a zip with a standalone Node.js server.
// See docs and examples at https://github.com/apollographql/awesome-launchpad

// graphql-tools combines a schema string with resolvers.
import { makeExecutableSchema } from 'graphql-tools';

// Construct a schema, using GraphQL schema language
const typeDefs = `
    type User {
        name: String!
        age: Int!
    }

    type Query {
        me: User
    }
`;

const user = { name: 'Williams', age: 26};

// Provide resolver functions for your schema fields
const resolvers = {
  Query: {
    me: (root, args, context) => {
      return user;
    },
  },
};

// Required: Export the GraphQL.js schema object as "schema"
export const schema = makeExecutableSchema({
  typeDefs,
  resolvers,
});

// Optional: Export a function to get context from the request. It accepts two
// parameters - headers (lowercased http headers) and secrets (secrets defined
// in secrets section). It must return an object (or a promise resolving to it).
export function context(headers, secrets) {
  return {
    headers,
    secrets,
  };
};

// Optional: Export a root value to be passed during execution
// export const rootValue = {};

// Optional: Export a root function, that returns root to be passed
// during execution, accepting headers and secrets. It can return a
// promise. rootFunction takes precedence over rootValue.
// export function rootFunction(headers, secrets) {
//   return {
//     headers,
//     secrets,
//   };
// };

Request:

{
  me
}

回复：

{
  "errors": [
    {
      "message": "Field \"me\" of type \"User\" must have a selection of subfields. Did you mean \"me { ... }\"?",
      "locations": [
        {
          "line": 4,
          "column": 3
        }
      ]
    }
  ]
}

有谁知道我做错了什么？如何修复它？

来自文档:

GraphQL 对象类型具有名称和字段，但在某些时候这些 字段必须解析为一些具体数据。这就是标量的地方 类型进来：它们代表查询的叶子。

GraphQL 要求您以仅返回的方式构建查询具体数据。每个字段最终都必须解析为一个或多个标量（或枚举）。这意味着您不能只请求解析为某种类型的字段，而不指示您想要返回该类型的哪些字段。

这就是您收到的错误消息告诉您的信息——您请求了User类型，但您没有告诉 GraphQL 至少有一个字段要从该类型返回。

要修复它，只需更改您的请求以包含name像这样：

{
  me {
    name
  }
}

... or age。或两者。但是，您不能请求特定类型并期望 GraphQL 为其提供所有字段——您始终必须为该类型提供一系列（一个或多个）字段。