如何在没有Apollo Server但具有express-graphql的情况下使用apollo-datasource-rest

npm install apollo-datasource-rest

const { RESTDataSource } = require('apollo-datasource-rest');

class MyRESTDataSource extends RESTDataSource {
  constructor() {
    super();
    this.baseURL = 'https://api.example.com/';
  }

  async getSomeData() {
    return this.get('endpoint');
  }

  async postData(data) {
    return this.post('endpoint', data);
  }

  // 其他自定义方法...
}

const { ApolloServer, gql } = require('apollo-server-express');
const { MyRESTDataSource } = require('./myRESTDataSource');

const typeDefs = gql`
  type Query {
    someData: [Data]
  }
`;

const resolvers = {
  Query: {
    someData: (_, __, { dataSources }) => {
      return dataSources.myRESTDataSource.getSomeData();
    },
  },
};

const server = new ApolloServer({
  typeDefs,
  resolvers,
  dataSources: () => ({
    myRESTDataSource: new MyRESTDataSource(),
  }),
});

// 将Apollo Server与express-graphql集成
const express = require('express');
const app = express();
server.applyMiddleware({ app });

app.listen({ port: 4000 }, () =>
  console.log(`Server ready at http://localhost:4000${server.graphqlPath}`)
);

query {
  someData {
    field1
    field2
    # ...
  }
}