使用Apollo Server时如何生成schema.graphql文件？

npm install apollo-server graphql

const { ApolloServer, gql } = require('apollo-server');
const fs = require('fs');

const typeDefs = gql`
  type Query {
    hello: String
  }
`;

const resolvers = {
  Query: {
    hello: () => 'Hello, world!',
  },
};

const server = new ApolloServer({ typeDefs, resolvers });

server.executeOperation({ query: '{ __schema { types { name } } }' })
  .then(result => {
    const schemaString = JSON.stringify(result.data, null, 2);
    fs.writeFileSync('schema.graphql', schemaString);
    console.log('schema.graphql文件已生成！');
  })
  .catch(error => {
    console.error('生成schema.graphql文件时出错：', error);
  });

node generateSchema.js