如何使用GraphQL和node实现接口

npm install express express-graphql graphql

const express = require('express');
const { graphqlHTTP } = require('express-graphql');
const { buildSchema } = require('graphql');

// 定义GraphQL schema
const schema = buildSchema(`
  type Query {
    hello: String
  }
`);

// 定义resolver函数
const root = {
  hello: () => 'Hello, World!'
};

// 创建Express服务器
const app = express();

// 添加GraphQL中间件
app.use('/graphql', graphqlHTTP({
  schema: schema,
  rootValue: root,
  graphiql: true // 开启GraphQL的可视化调试界面
}));

// 启动服务器
app.listen(3000, () => {
  console.log('Server started on port 3000');
});

node server.js

query {
  hello
}