text: const express = require('express');
  const { ApolloServer } = require('apollo-server-express');
  const { typeDefs, resolvers } = require('./schema');
  
  const server = new ApolloServer({
      typeDefs,
      resolvers,
  });
  
  const app = express();
  
  // Mount Apollo middleware here.
  server.applyMiddleware({ app, path: '/' });
  
  app.listen(8000);
  console.log('server listen url:http://localhost:' + 8000);