graphql-stuff.js

'use strict'

const {
  graphql,
  parse,
  buildSchema,
  extendSchema,
  buildASTSchema
} = require('graphql')

// const schema = buildSchema(`
// type Person {
//   name: String
// }
// 
// query names {
//   person {
//     name
//   }
// }
// 
// `)

const q1 = parse(`
  type Person {
    name: String
    age: Int
    friends: [Person]
  }

  type Query {
    add(x: Int, y: Int): Int
    people: [Person]
  }
`)

const q2 = parse(`
  extend type Query {
    add2(x: Int, y: Int): Int
  }
`)

const schema = extendSchema(buildASTSchema(q1), q2);

const root = {
  add: async ({ x, y }) => x + y,
  add2: async ({ x, y }) => 2 * x + y,
  people: async () => {
    return [{ name: 'Matteo', age: 34, friends }]
  }
};

async function friends () {
  console.log(this, arguments)
  return [{ name:'XYZ', age: 42 }]
}

// var schema = new GraphQLSchema({
//   query: new GraphQLObjectType({
//     name: 'RootQueryType',
//     fields: {
//       hello: {
//         type: GraphQLString,
//         resolve() {
//           return 'world';
//         }
//       }
//     }
//   })
// });

{
  var query = '{ add2(x: 2, y: 2) }';

  graphql(schema, query, root).then(result => {

    // Prints
    // {
    //   data: { hello: "world" }
    // }
    console.log(result);

  });
}

{
  var query = '{ people { name, friends { name } } }';

  graphql(schema, query, root).then(result => {

    // Prints
    // {
    //   data: { hello: "world" }
    // }
    console.log(JSON.stringify(result, null, 2));

  });
}